Barrier laminate, packaging container comprising the barrier laminate

Abstract

To provide a barrier laminate having an intermediate layer with excellent adhesion between layers and a vapor-deposited film, and possessing extremely high gas barrier properties. [Solution] The barrier laminate of the present invention comprises a substrate, an adhesive layer, a vapor-deposited film, an intermediate layer, and a sealant layer, wherein the intermediate layer comprises a surface coat layer and a polypropylene resin layer, the polypropylene resin layer is subjected to stretching treatment, and the surface coat layer contains a resin material having polar groups, the barrier laminate comprises the vapor-deposited film on the surface coat layer, the vapor-deposited film is composed of an inorganic oxide, the substrate and the sealant layer are composed of polypropylene, and the polypropylene content relative to the total amount of resin material contained in the barrier laminate is 80% by mass or more.

Description

[Technical Field]

[0001] The present invention relates to a barrier laminate and a packaging container comprising the barrier laminate. [Background technology]

[0002] Conventionally, films made of polyester such as polyethylene terephthalate (hereinafter also referred to as polyester films) have been used as base materials or intermediate layers in laminates used to manufacture packaging containers because they have excellent mechanical properties, chemical stability, heat resistance, and transparency, as well as being inexpensive.

[0003] Depending on the contents to be filled into the packaging container, the packaging container may require high oxygen barrier properties and gas barrier properties such as water vapor barrier properties. To meet these requirements, it is common practice to form a vapor-deposited film containing alumina or silica on the surface of a polyester film (Patent Document 1).

[0004] Incidentally, in recent years, research has been conducted to find alternative resin materials to polyester films, and the application of polyolefin films, particularly polypropylene films, with a vapor-deposited film formed on their surface as an intermediate layer is being considered. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2005-053223 [Overview of the project] [Problems that the invention aims to solve]

[0006] The inventors of the present invention were considering using a stretched polypropylene film (hereinafter also referred to as stretched polypropylene film) as a replacement for conventional polyester films, when they discovered a new problem: even when a vapor-deposited film was formed on the surface of the stretched polypropylene film, satisfactory gas barrier properties could not be obtained.

[0007] Further investigation by the inventors revealed that in packaging containers using a barrier laminate in which a vapor-deposited film is provided on a stretched polypropylene film, a unique phenomenon not seen in conventional barrier laminates using polyester film occurs: delamination occurs between the stretched polypropylene film and the vapor-deposited film. The inventors concluded that this phenomenon results in insufficient gas barrier properties.

[0008] Furthermore, the inventors have found that by providing a surface resin layer containing a resin material having a melting point of 180°C or higher on the surface of a stretched polypropylene film, the adhesion of the vapor-deposited film formed on the surface resin layer is improved, as is the gas barrier properties.

[0009] Furthermore, the inventors have found that by providing a coating layer containing a resin material having polar groups on the surface of a stretched polypropylene film, the adhesion of the vapor-deposited film formed on the coating layer is improved, as well as the gas barrier properties.

[0010] This invention is based on the aforementioned findings, and the problem it aims to solve is to provide a barrier laminate that has an intermediate layer with excellent interlayer adhesion to a vapor-deposited film and possesses extremely high gas barrier properties.

[0011] Furthermore, the problem that the present invention aims to solve is to provide a packaging container equipped with the barrier laminate. [Means for solving the problem]

[0012] The barrier laminate of the present invention comprises a substrate, an adhesive layer, a vapor-deposited film, an intermediate layer, and a sealant layer. The intermediate layer includes a surface coating layer and a polypropylene resin layer. The polypropylene resin layer has been subjected to a stretching treatment. And the surface coating layer contains a resin material having a polar group. The barrier laminate has the vapor deposition film on the surface coating layer. The vapor deposition film is composed of an inorganic oxide. The base material and the sealant layer are composed of polypropylene. The content of polypropylene with respect to the total amount of the resin materials contained in the barrier laminate is 80% by mass or more, which is characteristic.

[0013] In one embodiment, the adhesive layer is an adhesive layer containing a cured product of a composition containing a polyester polyol and an isocyanate compound.

[0014] In one embodiment, the ratio of the thickness of the surface coating layer to the total thickness of the intermediate layer is 0.08% or more and 20% or less.

[0015] In one embodiment, the thickness of the surface coating layer is 0.02 μm or more and 10 μm or less.

[0016] In one embodiment, the resin material is one or more resin materials selected from ethylene vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, nylon 6, nylon 6,6, MXD nylon, amorphous nylon, and polyurethane.

[0017] In one embodiment, the surface coating layer is a layer formed using an aqueous emulsion or a solvent-based emulsion.

[0018] In one embodiment, the barrier laminate of the present invention further includes a barrier coating layer between the adhesive layer and the vapor deposition film.

[0019] In one embodiment, the barrier laminate of the present invention is used for packaging container applications.

[0020] The packaging container of the present invention is characterized by comprising the above-mentioned barrier laminate. [Effects of the Invention]

[0021] According to the present invention, it is possible to produce a packaging container having high lamination strength, which includes an intermediate layer with excellent interlayer adhesion to the vapor-deposited film, and to provide a barrier laminate with extremely high gas barrier properties. Furthermore, according to the present invention, a packaging container comprising the barrier laminate can be provided. [Brief explanation of the drawing]

[0022] [Figure 1] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 2] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 3] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 4] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 5] This is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. [Figure 6] This is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. [Figure 7] This is a schematic cross-sectional view showing another embodiment of the vapor deposition apparatus. [Figure 8] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 9] This is a schematic cross-sectional view showing one embodiment of the barrier laminate of the present invention. [Figure 10] This is a front view showing one embodiment of the packaging container of the present invention. [Figure 11] This is a perspective view showing one embodiment of the packaging container of the present invention. [Figure 12]This is a schematic diagram illustrating an example of a method for measuring laminate strength. [Figure 13] This is a schematic diagram illustrating an example of a method for measuring laminate strength. [Figure 14] This figure shows the change in tensile stress with respect to the distance between a pair of grips used to pull the substrate side and the sealant layer side in order to measure the laminate strength. [Modes for carrying out the invention]

[0023] (Barrier laminate in the first embodiment) As shown in Figure 1, the barrier laminate 10 of the present invention comprises a substrate 11, an adhesive layer 12, a vapor-deposited film 13, an intermediate layer 14, and a sealant layer 15, wherein the intermediate layer 14 comprises at least a surface resin layer 16 and a polypropylene resin layer 17. In one embodiment, the barrier laminate 10 of the present invention further comprises a barrier coat layer 18 between the adhesive layer 12 and the vapor-deposited film 13, as shown in Figure 2. In one embodiment, the intermediate layer 14 includes an adhesive resin layer 19 between the surface resin layer 16 and the polypropylene resin layer 17, as shown in Figure 3. In one embodiment, as shown in Figure 4, the barrier laminate 10 comprises, in order, a substrate 11, an adhesive layer 12, a barrier coat layer 18, a vapor-deposited film 13, an intermediate layer 14, and a sealant layer 15. The intermediate layer 14 comprises at least a surface resin layer 16 and a polypropylene resin layer 17, and the adhesive resin layer 19 is provided between the surface resin layer 16 and the polypropylene resin layer 17.

[0024] In the barrier laminate according to the first embodiment, the laminate strength between the intermediate layer and the vapor-deposited film is preferably 3N or more, more preferably 4N or more, and even more preferably 5.5N or more, with a width of 15 mm. The upper limit of the laminate strength of the barrier laminate in the first embodiment may be 20N or less. The method for measuring the laminate strength of the barrier laminate will be explained in the examples described later.

[0025] Traditionally, laminates consisting of a base material, an intermediate layer, and a sealant layer made of different resin materials have been used to manufacture packaging containers. However, because it is difficult to separate the layers, which are made of different resin materials, after used packaging containers are collected, they are not actively recycled. By constructing the base material, the polypropylene resin layer in the intermediate layer, and the sealant layer from the same material, there is no need to separate each layer, which improves the recyclability. By constructing the base material and sealant from the same material as the polypropylene resin layer in the intermediate layer, i.e., polypropylene, it becomes unnecessary to separate the packaging container layer by layer after collection, thereby improving its recyclability.

[0026] When the base material and sealant layer are made of polypropylene, the polypropylene content relative to the total amount of resin material contained in the barrier laminate of the present invention is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more. This makes it possible to further improve the recyclability of packaging containers made using the barrier laminate of the present invention.

[0027] The following describes each layer of the barrier laminate of the present invention.

[0028] (base material) The base material includes resin materials, such as polyolefins, vinyl resins, (meth)acrylic resins, cellulose resins, polyamides, polyimides, polyesters, and ionomer resins. From the viewpoint of the recyclability of the barrier laminate of the present invention, it is preferable that the base material is made of the same material as the polypropylene resin layer of the intermediate layer, i.e., polypropylene. Furthermore, by constructing the base material from polypropylene, the oil resistance of packaging containers made using barrier laminates can be improved.

[0029] Within the limits that do not impair the properties of the present invention, the substrate may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0030] The substrate may have a single-layer structure or a multi-layer structure. Furthermore, the base material may be stretched or not, but from the viewpoint of heat resistance and strength of the barrier laminate, it is preferable that it be stretched.

[0031] The thickness of the substrate is preferably 10 μm or more and 50 μm or less, and more preferably 20 μm or more and 40 μm or less. By making the substrate thickness 10 μm or more, the strength and heat resistance of the barrier laminate of the present invention can be improved. Furthermore, by setting the thickness of the substrate to 50 μm or less, the film-forming properties and processability of the barrier laminate of the present invention can be further improved.

[0032] The substrate may have a printed layer on its surface, and the image formed on the printed layer is not particularly limited and may represent characters, patterns, symbols, or combinations thereof. The printing layer on the substrate can be formed using biomass-derived ink. This reduces the environmental impact. The method for forming the printed layer is not particularly limited and can be described as conventionally known printing methods such as gravure printing, offset printing, and flexographic printing.

[0033] (Adhesive layer) The barrier laminate of the present invention comprises an adhesive layer between the substrate and the vapor-deposited film.

[0034] The adhesive layer contains at least one type of adhesive, which may be a one-component curing type, a two-component curing type, or a non-curing type. The adhesive may be a solvent-free type or a solvent-based type, but from the viewpoint of environmental impact, a solvent-free type adhesive is preferably used. Examples of solvent-free adhesives include polyether-based adhesives, polyester-based adhesives, silicone-based adhesives, epoxy-based adhesives, and urethane-based adhesives. Among these, two-component curing type urethane-based adhesives are preferably used. Examples of solvent-based adhesives include rubber-based adhesives, vinyl-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and olefin-based adhesives.

[0035] Furthermore, the adhesive layer is preferably an adhesive layer containing a cured product of a composition comprising a polyester polyol and an isocyanate compound. By configuring the adhesive layer in this way, the oxygen barrier and water vapor barrier properties of the barrier laminate of the present invention can be further improved. Furthermore, when laminates with vapor-deposited films are typically applied to packaging containers, bending loads are applied to the laminate by molding machines, etc., which can cause cracks in the vapor-deposited film. By using a gas barrier organic adhesive, the bending load resistance of the barrier laminate of the present invention can be improved, and the decrease in oxygen barrier properties and water vapor barrier properties can be suppressed.

[0036] The glass transition temperature of the cured product of a composition containing a polyester polyol and an isocyanate compound is preferably -30°C to 80°C, more preferably 0°C to 70°C, and even more preferably 25°C to 70°C. This allows for further improvement of the oxygen barrier properties, water vapor barrier properties, and laminate strength of the barrier laminate. In this specification, Tg is a value obtained by differential scanning calorimetry (DSC) in accordance with JIS K 7121:2012.

[0037] Polyester polyols have two or more hydroxyl groups as functional groups in one molecule. Isocyanate compounds, on the other hand, have two or more isocyanate groups as functional groups in one molecule. Polyester polyols have, for example, a polyester structure or a polyester polyurethane structure as their main backbone.

[0038] A specific example of a composition (adhesive) containing polyester polyols and isocyanate compounds is the PASLIM series sold by DIC Corporation.

[0039] The composition comprising a polyester polyol and an isocyanate compound may further contain phosphate esters, plate-like inorganic compounds, coupling agents, cyclodextrins and / or derivatives thereof.

[0040] Examples of polyester polyols having two or more hydroxyl groups in one molecule as functional groups include the following [Example 1] to [Example 3]. [Example 1] Polyester polyol obtained by polycondensation of an ortho-oriented polycarboxylic acid or its anhydride with a polyhydric alcohol [Example 2] Polyester polyol having a glycerol skeleton [Example 3] Polyester polyol having an isocyanuric ring The following describes each type of polyester polyol.

[0041] The polyester polyol in the first example is a polycondensate obtained by polycondensing a polycarboxylic acid component containing at least one orthophthalic acid and its anhydride with a polyhydric alcohol component. In particular, polyester polyols in which orthophthalic acid and its anhydride are present in a proportion of 70 to 100% by mass relative to the total polycarboxylic acid components are preferred.

[0042] The polyester polyol according to the first example requires orthophthalic acid and its anhydride as polycarboxylic acid components, but other polycarboxylic acid components may be copolymerized to the extent that the effects of this embodiment are not impaired. Other polycarboxylic acid components include, for example, aliphatic polycarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid; unsaturated bond-containing polycarboxylic acids such as maleic anhydride, maleic acid, and fumaric acid; alicyclic polycarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; terephthalic acid, isophthalic acid, pyromellitic acid, trimellitic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-p,p'-dicarboxylic acid, anhydrides of these dicarboxylic acids, and ester-forming derivatives of these dicarboxylic acids, as well as aromatic polycarboxylic acids; and polybasic acids such as p-hydroxybenzoic acid, p-(2-hydroxyethoxy)benzoic acid, and ester-forming derivatives of these dihydroxycarboxylic acids. Among these, succinic acid, 1,3-cyclopentanedicarboxylic acid, and isophthalic acid are preferred. Furthermore, two or more of the above-mentioned polycarboxylic acids may be used.

[0043] Examples of polyhydric alcohol components include aliphatic polyhydric alcohols and aromatic polyhydric alcohols. Examples of aliphatic polyhydric alcohols include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, cyclohexanedimethanol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. Examples of aromatic polyhydric alcohols include hydroquinone, resorcinol, catechol, naphthalenediol, biphenol, bisphenol A, bisphenol F, tetramethylbiphenol, their ethylene oxide extensions, and their hydrolyzed aliphatic compounds. In one embodiment, the polyhydric alcohol component includes at least one selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol.

[0044] As an example of a polyester polyol related to the second example, a polyester polyol having a glycerol skeleton represented by general formula (1) can be mentioned. [ka] In general formula (1), R1, R2, and R3 are each independently either H (hydrogen atom) or a group represented by the following general formula (2). [ka]

[0045] In formula (2), n represents an integer from 1 to 5, X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents, and Y represents an alkylene group having 2 to 6 carbon atoms. However, at least one of R1, R2, and R3 represents a group represented by general formula (2).

[0046] In general formula (1), at least one of R1, R2, and R3 must be a group represented by general formula (2). In particular, it is preferable that all of R1, R2, and R3 are groups represented by general formula (2).

[0047] Furthermore, the compound may be a mixture of two or more compounds in which one of R1, R2, or R3 is a group represented by general formula (2), two of R1, R2, or R3 are groups represented by general formula (2), or all of R1, R2, and R3 are groups represented by general formula (2).

[0048] X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents. If X is substituted by a substituent, it may be substituted by one or more substituents, the substituents being bonded to any carbon atom on X that is different from the free radical. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups.

[0049] In general formula (2), Y represents an alkylene group having 2 to 6 carbon atoms, such as an ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene group, and dimethylbutylene group. Among these, propylene and ethylene groups are preferred, with ethylene being the most preferred.

[0050] Polyester resin compounds having a glycerol skeleton represented by general formula (1) can be synthesized by reacting glycerol with an aromatic polycarboxylic acid or its anhydride in which the carboxylic acid is substituted in the ortho position, and a polyhydric alcohol component as essential components.

[0051] Examples of aromatic polycarboxylic acids or their anhydrides in which the carboxylic acid is substituted at the ortho position include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, and 2,3-anthracenecarboxylic acid or its anhydride. These compounds may have substituents on any carbon atom of the aromatic ring. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups.

[0052] Furthermore, examples of polyhydric alcohol components include alkylenediols having 2 to 6 carbon atoms. Examples of diols include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, and dimethylbutanediol.

[0053] The polyester polyol in the third example is a polyester polyol having an isocyanuric ring represented by the following general formula (3). [ka] In general formula (3), R1, R2, and R3 each independently represent either "-(CH2)n1-OH (where n1 is an integer from 2 to 4)" or the structure of general formula (4). [ka]

[0054] In general formula (4), n2 represents an integer from 2 to 4, n3 represents an integer from 1 to 5, X represents an arylene group selected from the group consisting of 1,2-phenylene, 1,2-naphthylene, 2,3-naphthylene, 2,3-anthraquinonediyl, and 2,3-anthracenediyl groups, which may have substituents, and Y represents an alkylene group having 2 to 6 carbon atoms. However, at least one of R1, R2, and R3 is a group represented by general formula (4).

[0055] In general formula (3), the alkylene group represented by -(CH2)n1- may be linear or branched. n1 is preferably 2 or 3, with 2 being the most preferred.

[0056] In general formula (4), n² represents an integer between 2 and 4, and n³ represents an integer between 1 and 5. X represents an arylene group selected from the group consisting of a 1,2-phenylene group, a 1,2-naphthylene group, a 2,3-naphthylene group, a 2,3-anthraquinonediyl group, and a 2,3-anthracenediyl group, which may have substituents.

[0057] If X is substituted by a substituent, it may be substituted by one or more substituents, the substituents being bonded to any carbon atom on X that is different from the free radical. Examples of substituents include chloro, bromo, methyl, ethyl, i-propyl, hydroxyl, methoxy, ethoxy, phenoxy, methylthio, phenylthio, cyano, nitro, amino, phthalimide, carboxyl, carbamoyl, N-ethylcarbamoyl, phenyl, and naphthyl groups. The substituents of X are preferably hydroxyl, cyano, nitro, amino, phthalimide, carbamoyl, N-ethylcarbamoyl, and phenyl groups, with hydroxyl, phenoxy, cyano, nitro, phthalimide, and phenyl groups being the most preferred.

[0058] In general formula (4), Y represents an alkylene group having 2 to 6 carbon atoms, such as an ethylene group, propylene group, butylene group, neopentylene group, 1,5-pentylene group, 3-methyl-1,5-pentylene group, 1,6-hexylene group, methylpentylene group, and dimethylbutylene group. Among these, propylene and ethylene groups are preferred, with ethylene being the most preferred.

[0059] In general formula (3), at least one of R1, R2, and R3 is a group represented by general formula (4). In particular, it is preferable that all of R1, R2, and R3 are groups represented by general formula (4).

[0060] Furthermore, the compound may be a mixture of two or more compounds in which one of R1, R2, or R3 is a group represented by general formula (4), two of R1, R2, or R3 are groups represented by general formula (4), or all of R1, R2, and R3 are groups represented by general formula (4).

[0061] Polyester polyols having an isocyanuric ring, represented by general formula (3), can be synthesized by reacting a triol having an isocyanuric ring with an aromatic polycarboxylic acid or its anhydride in which the carboxylic acid is substituted in the ortho position, and a polyhydric alcohol component as essential components.

[0062] Examples of triols having an isocyanuric ring include alkylene oxide adducts of isocyanuric acids such as 1,3,5-tris(2-hydroxyethyl)isocyanuric acid and 1,3,5-tris(2-hydroxypropyl)isocyanuric acid.

[0063] Furthermore, examples of aromatic polycarboxylic acids or their anhydrides in which the carboxylic acid is substituted at the ortho position include orthophthalic acid or its anhydride, naphthalene 2,3-dicarboxylic acid or its anhydride, naphthalene 1,2-dicarboxylic acid or its anhydride, anthraquinone 2,3-dicarboxylic acid or its anhydride, and 2,3-anthracenecarboxylic acid or its anhydride. These compounds may have substituents on any carbon atom of the aromatic ring.

[0064] Examples of substituents include chloro group, bromo group, methyl group, ethyl group, i-propyl group, hydroxyl group, methoxy group, ethoxy group, phenoxy group, methylthio group, phenylthio group, cyano group, nitro group, amino group, phthalimide group, carboxyl group, carbamoyl group, N-ethylcarbamoyl group, phenyl group, and naphthyl group.

[0065] Furthermore, examples of polyhydric alcohol components include alkylenediols having 2 to 6 carbon atoms. Examples include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, methylpentanediol, and dimethylbutanediol. In particular, polyester polyol compounds having an isocyanuric ring are preferred when 1,3,5-tris(2-hydroxyethyl)isocyanuric acid or 1,3,5-tris(2-hydroxypropyl)isocyanuric acid is used as the triol compound having an isocyanuric ring, an aromatic polycarboxylic acid in which the carboxylic acid is substituted at the ortho position or orthophthalic anhydride is used as the anhydride, and ethylene glycol is used as the polyhydric alcohol, as these compounds exhibit particularly excellent oxygen barrier properties and adhesion.

[0066] The isocyanuric ring is highly polar and trifunctional, which can increase the overall polarity of the system and increase the crosslinking density. From this viewpoint, it is preferable to contain 5% by mass or more of the isocyanuric ring relative to the total solid content of the adhesive resin.

[0067] Isocyanate compounds have two or more isocyanate groups in their molecule. Furthermore, the isocyanate compound may be aromatic or aliphatic, and may be a low-molecular-weight compound or a high-molecular-weight compound. Furthermore, the isocyanate compound may be a blocked isocyanate compound obtained by an addition reaction using a known isocyanate blocking agent by a known and conventional method. In particular, polyisocyanate compounds having three or more isocyanate groups are preferred from the viewpoint of adhesion and retort resistance, and aromatic compounds are preferred from the viewpoint of oxygen barrier properties and water vapor barrier properties.

[0068] Specific examples of isocyanate compounds include, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, metaxylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds, as well as adducts, burettes, and allophanates obtained by reacting these isocyanate compounds with low molecular weight active hydrogen compounds or their alkylene oxide adducts, or high molecular weight active hydrogen compounds. Examples of low molecular weight active hydrogen compounds include ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, and metaxylylenediamine. Examples of molecular weight active hydrogen compounds include high molecular weight active hydrogen compounds of various polyester resins, polyether polyols, and polyamides.

[0069] The adhesive layer, composed of a cured product of a composition containing a polyester polyol and an isocyanate compound, may contain a phosphate-modified compound, such as a compound represented by the following general formula (5) or (6). [ka] In general formula (5), R1, R2, and R3 are groups selected from a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth)acryloyl group, an optionally substituted phenyl group, and an alkyl group having 1 to 4 carbon atoms, but at least one of them is a hydrogen atom, and n represents an integer from 1 to 4. [ka] In the formula, R4 and R5 are groups selected from a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a (meth)acryloyl group, an optionally substituted phenyl group, and an alkyl group having 1 to 4 carbon atoms with a (meth)acryloyloxy group, where n is an integer from 1 to 4, x is an integer from 0 to 30, and y is an integer from 0 to 30, except when both x and y are 0.

[0070] More specifically, examples include phosphoric acid, pyrophosphate, triphosphate, methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, dibutyl phosphate, 2-ethylhexyl acid phosphate, bis(2-ethylhexyl) phosphate, isododecyl acid phosphate, butoxyethyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, 2-hydroxyethyl methacrylate acid phosphate, and polyoxyethylene alkyl ether phosphate, and one or more of these can be used.

[0071] The content of the phosphate-modified compound in the adhesive layer containing the polyester polyol and the isocyanate compound is preferably 0.005% by mass or more and 10% by mass or less, and more preferably 0.01% by mass or more and 1% by mass or less. By setting the content of the phosphate-modified compound to 0.005% by mass or more, oxygen barrier properties and water vapor barrier properties can be improved. Furthermore, by setting the content of the phosphate-modified compound to 10% by mass or less, the adhesion of the adhesive layer can be improved.

[0072] The adhesive layer containing the polyester polyol and isocyanate compound may also contain a plate-like inorganic compound, which can improve the oxygen barrier properties, water vapor barrier properties, and adhesive properties of the adhesive layer. Furthermore, the bending load resistance of the barrier laminate of the present invention can be improved. Examples of plate-like inorganic compounds include kaolinite-serpentine clay minerals (haloysite, kaolinite, endelite, dickite, nacrite, antigorite, chrysotile, etc.) and pyrophyllite-talc group minerals (pyrophyllite, talc, kerolite, etc.).

[0073] Examples of coupling agents include silane-based coupling agents, titanium-based coupling agents, and aluminum-based coupling agents represented by the general formula (7) below. These coupling agents may be used individually or in combination of two or more types. [ka]

[0074] Examples of silane coupling agents include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxytrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, N-β( Examples include aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-isocyanatetopropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, and 3-triethoxysilyl-N-(1,3-dimethylbutylidene).

[0075] Examples of titanium-based coupling agents include isopropyl triisostearoyl titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, tetraoctyl bis(didodecyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctainol titanate, isopropyl dimethacrylate isostearoyl titanate, isopropyl isostearoyl diacrylic titanate, diisostearoylethylene titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, and dicumylphenyl oxyacetate titanate.

[0076] Specific examples of aluminum-based coupling agents include, for example, acetalkoxyaluminum diisopropylate, diisopropoxyaluminum ethyl acetacetate, diisopropoxyaluminum monomethacrylate, isopropoxyaluminum alkyl acetacetate mono(dioctyl phosphate), aluminum-2-ethylhexanoate oxide trimer, aluminum stearate oxide trimer, and alkyl acetacetate aluminum oxide trimer.

[0077] The adhesive layer, composed of a polyester polyol and an isocyanate compound, may contain cyclodextrin and / or its derivatives, thereby improving the adhesive properties of the adhesive layer. Furthermore, it can further improve the resistance to flexural loads. Specifically, for example, cyclodextrins such as alkylated cyclodextrins, acetylated cyclodextrins, and hydroxyalkylated cyclodextrins, in which the hydrogen atom of the hydroxyl group of the glucose unit of a cyclodextrin is substituted with another functional group, can be used. Branched cyclic dextrins can also be used. Furthermore, the cyclodextrin skeleton in cyclodextrins and cyclodextrin derivatives may be any of the following: α-cyclodextrin consisting of 6 glucose units, β-cyclodextrin consisting of 7 glucose units, or γ-cyclodextrin consisting of 8 glucose units. These compounds may be used individually or in combination of two or more. Furthermore, these cyclodextrins and / or their derivatives may collectively be referred to as dextrin compounds from now on.

[0078] From the viewpoint of compatibility and dispersibility in an adhesive layer containing a polyester polyol and an isocyanate compound, it is preferable to use a cyclodextrin derivative as the cyclodextrin compound. From the viewpoint of the polarity of the various resins mentioned above, the degree of substitution is preferably in the range of 0.1 to 14 molecules / glucose, and more preferably in the range of 0.3 to 8 molecules / glucose.

[0079] Examples of alkylated cyclodextrins include methyl-α-cyclodextrin, methyl-β-cyclodextrin, and methyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0080] Examples of acetylated cyclodextrins include monoacetyl-α-cyclodextrin, monoacetyl-β-cyclodextrin, and monoacetyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0081] Examples of hydroxyalkylated cyclodextrins include hydroxypropyl-α-cyclodextrin, hydroxypropyl-β-cyclodextrin, and hydroxypropyl-γ-cyclodextrin. These compounds may be used individually or in combination of two or more.

[0082] The thickness of the adhesive layer is preferably 0.5 μm or more and 6 μm or less, more preferably 0.8 μm or more and 5 μm or less, and even more preferably 1 μm or more and 4.5 μm or less. By increasing the thickness of the adhesive layer to 0.5 μm or more, the adhesion of the adhesive layer can be improved. Furthermore, if the adhesive layer is an adhesive layer containing a cured product of a composition containing a polyester polyol and an isocyanate compound, the bending load resistance can be improved. By reducing the thickness of the adhesive layer to 6 μm or less, the processability of the barrier laminate can be improved. Furthermore, the recyclability of packaging containers made using laminates comprising a polypropylene substrate and a sealant layer can be improved.

[0083] The adhesive layer can be formed by applying and drying it on a vapor-deposited film or the like using conventionally known methods such as the direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, fontein method, and transfer roll coating method.

[0084] (Vaporized film) The barrier laminate of the present invention comprises a vapor-deposited film composed of an inorganic oxide on a surface resin layer. This improves the gas barrier properties of the barrier laminate, specifically its oxygen barrier properties and water vapor barrier properties. Furthermore, it can suppress the mass reduction of the contents filled into a packaging container made using the barrier laminate of the present invention.

[0085] Examples of inorganic oxides include aluminum oxide (alumina), silicon oxide (silica), magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, barium oxide, and silicon carbide oxide (carbon-containing silicon oxide). Among the above, silica, silicon carbide oxide, and alumina are preferred. Furthermore, silica is particularly preferred because it eliminates the need for aging treatment after the deposition film is formed.

[0086] Furthermore, the thickness of the deposited film is preferably 1 nm to 150 nm, more preferably 5 nm to 60 nm, and even more preferably 10 nm to 40 nm. By increasing the thickness of the deposited film to 1 nm or more, the oxygen barrier and water vapor barrier properties of the laminate can be further improved. Furthermore, by limiting the thickness of the vapor-deposited film to 150 nm or less, the occurrence of cracks in the vapor-deposited film can be prevented. In addition, the recyclability of packaging containers made using laminates comprising a polypropylene substrate and a sealant layer can be improved.

[0087] The deposition film can be formed using conventionally known methods, such as physical vapor deposition (PVD) methods including vacuum deposition, sputtering, and ion plating, and chemical vapor deposition (CVD) methods including plasma chemical vapor deposition, thermochemical vapor deposition, and photochemical vapor deposition.

[0088] The vapor-deposited film may be a single layer formed by a single vapor deposition process, or a multilayer formed by multiple vapor deposition processes. If it is a multilayer, each layer may be made of the same material or different materials. Furthermore, each layer may be formed by the same method or by different methods.

[0089] A vacuum deposition apparatus with plasma assistance can be used as the equipment for forming vapor-deposited films by the PVD method. One embodiment of a method for depositing a vapor-deposited film using a vacuum deposition apparatus with plasma assistance is described below. In one embodiment, the vacuum film deposition apparatus, as shown in Figures 5 and 6, comprises a vacuum vessel A, an unwinding section B, a film deposition drum C, a winding section D, a transport roll E, an evaporation source F, a reaction gas supply section G, an anti-deposition box H, a deposition material I, and a plasma gun J. Figure 5 is a schematic cross-sectional view of the vacuum deposition apparatus in the XZ plane, and Figure 6 is a schematic cross-sectional view of the vacuum deposition apparatus in the XY plane. As shown in Figure 4, the intermediate layer 14 wound onto the film-forming drum C is positioned at the top of the vacuum vessel A with its surface resin layer facing downwards, and an electrically grounded protective box H is positioned below the film-forming drum C inside the vacuum vessel A. An evaporation source F is positioned on the bottom of the protective box H. The film-forming drum C is positioned inside the vacuum vessel A such that the surface resin layer of the intermediate layer 10 wound onto the film-forming drum C is positioned opposite the top surface of the evaporation source F at a certain distance. Furthermore, a transport roll E is positioned between the unwinding section B and the film-forming drum C, and between the film-forming drum C and the winding section D. The vacuum vessel is connected to a vacuum pump (not shown). The evaporation source F is for holding the deposition material I and is equipped with a heating device (not shown). The reaction gas supply unit G is the part that supplies reaction gases (such as oxygen, nitrogen, helium, argon, and mixtures thereof) that react with the evaporated deposition material. The evaporated deposition material I, heated from the evaporation source F, is irradiated onto the surface resin layer of the intermediate layer 14. Simultaneously, plasma is also irradiated onto the surface resin layer from the plasma gun J, and a deposited film is formed. Details of this formation method are disclosed in Japanese Patent Publication No. 2011-214089.

[0090] Plasma generators used in plasma chemical vapor deposition (PVM) can include high-frequency plasma, pulsed-wave plasma, and microwave plasma generators. Alternatively, a device with two or more deposition chambers may be used. Preferably, the device is equipped with a vacuum pump and capable of maintaining a vacuum in each deposition chamber. The vacuum level in each deposition chamber is 1 × 10 to 1 × 10 -6 Pa is preferable. One embodiment of a method for depositing a vapor-deposited film using a plasma generator is described below. First, the intermediate layer is sent to the deposition chamber and transported onto the cooling / electrode drum at a predetermined speed via an auxiliary roll. Next, a mixed gas composition containing a monomer gas for film formation containing inorganic oxides, oxygen gas, and an inert gas is supplied from the gas supply device into the film deposition chamber. Plasma is generated on the surface resin layer by glow discharge and irradiated to form a vapor-deposited film containing inorganic oxides on the surface resin layer. Details of this formation method are disclosed in Japanese Patent Publication No. 2012-076292.

[0091] Figure 7 is a schematic diagram showing a plasma chemical vapor deposition apparatus used in the CVD method.

[0092] In one embodiment, as shown in Figure 7, the plasma chemical vapor deposition apparatus unwinds an intermediate layer 14 from an unwinding section B1 located inside a vacuum vessel A1, and then transports the intermediate layer 14 at a predetermined speed onto the surface of a cooling electrode drum C1 via a transport roll E1. Oxygen, nitrogen, helium, argon, and mixed gases thereof are supplied from G1 as reaction gases, and film-forming monomer gases are supplied from a raw material gas supply section I1. The vapor deposition mixed gas composition consisting of these gases is adjusted and introduced into the vacuum vessel A1 through a raw material supply nozzle H1. Then, a plasma is generated by a glow discharge plasma F1 on the surface resin layer of the intermediate layer 14 transported onto the surface of the cooling electrode drum C1, and this plasma is irradiated to form a vapor-deposited film. At this time, the cooling electrode drum C1 is supplied with a predetermined power from a power supply K1 located outside the vacuum vessel A1, and a magnet J1 is placed near the cooling electrode drum C1 to promote plasma generation. Next, after forming a vapor-deposited film, the intermediate layer 14 is wound onto the winding section D1 via the transport roll E1 at a predetermined winding speed. In the figure, L1 represents a vacuum pump.

[0093] A continuous vapor deposition apparatus equipped with a plasma pretreatment chamber and a deposition chamber can be used as the apparatus for forming vapor-deposited films. One embodiment of a method for forming a vapor-deposited film using the apparatus is described below. First, in the plasma pretreatment chamber, plasma is irradiated from a plasma supply nozzle onto the surface resin layer of the intermediate layer. Next, in the deposition chamber, a vapor-deposited film is formed on the plasma-treated surface resin layer. Details of this formation method are disclosed in the international publication WO2019 / 087960.

[0094] It is preferable that the surface of the deposited film is subjected to the above-mentioned surface treatment. This improves adhesion with adjacent layers.

[0095] In the barrier laminate of the present invention, the vapor-deposited film is preferably a vapor-deposited film formed by the CVD method, and more preferably a carbon-containing silicon oxide vapor-deposited film formed by the CVD method. This makes it possible to suppress the decrease in gas barrier properties even when the barrier laminate is bent.

[0096] A carbon-containing silicon oxide vapor-deposited film contains silicon, oxygen, and carbon. In a carbon-containing silicon oxide vapor-deposited film, the proportion of carbon C is preferably 3% to 50%, more preferably 5% to 40%, and even more preferably 10% to 35%, relative to 100% of the total of the three elements silicon, oxygen, and carbon. In a carbon-containing silicon oxide vapor-deposited film, by setting the carbon content C within the above range, the decrease in gas barrier properties can be suppressed even when the barrier laminate is bent. In this specification, the proportions of each element are expressed on a molar basis.

[0097] In one embodiment of the carbon-containing silicon oxide vapor-deposited film, the proportion of silicon (Si) is preferably 1% to 45%, more preferably 3% to 38%, and even more preferably 8% to 33%, relative to 100% of the total of the three elements silicon, oxygen, and carbon. The proportion of oxygen (O) is preferably 10% to 70%, more preferably 20% to 65%, and even more preferably 25% to 60%, relative to 100% of the total of the three elements silicon, oxygen, and carbon. In a carbon-containing silicon oxide vapor-deposited film, by setting the silicon content (Si) and oxygen content (O) within the above range, the decrease in gas barrier properties can be further suppressed even when the barrier laminate is bent.

[0098] In one embodiment of a carbon-containing silicon oxide vapor-deposited film, the proportion of oxygen (O) is preferably higher than the proportion of carbon (C), and the proportion of silicon (Si) is preferably lower than the proportion of carbon (C). The proportion of oxygen (O) is preferably higher than the proportion of silicon (Si), meaning that the proportions are preferably decreasing in the order of O, C, and Si. This further suppresses the decrease in gas barrier properties even when the barrier laminate is bent.

[0099] The proportions of C, Si, and O in a carbon-containing silicon oxide vapor-deposited film can be measured by X-ray photoelectron spectroscopy (XPS) using narrow-scan analysis under the following measurement conditions. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectrum acquisition conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): Approximately 6 mmφ Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ionic species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching area: 10mmφ Ion sputtering was performed for 30 seconds, and the spectrum was collected.

[0100] (Middle class) The intermediate layer comprises at least a surface resin layer and a polypropylene resin layer. The intermediate layer may also include an adhesive resin layer between the polypropylene resin layer and the surface resin layer. In the present invention, the surface resin layer and the polypropylene resin layer constituting the intermediate layer (if an adhesive resin layer is provided, the surface resin layer, the polypropylene resin layer, and the adhesive resin layer) are subjected to a stretching treatment, and this stretching treatment may be uniaxial stretching or biaxial stretching. The stretch ratio in the longitudinal (MD direction) and transverse (TD direction) directions of the intermediate layer is preferably 2 times or more and 15 times or less, and preferably 5 times or more and 13 times or less. By increasing the stretching ratio to 2 times or more, the strength and heat resistance of the intermediate layer can be further improved. Furthermore, the printability of the intermediate layer can be improved. Furthermore, from the viewpoint of the fracture limit of the intermediate layer, it is preferable that the stretch ratio is 15 times or less. Furthermore, when the polypropylene resin layer in the intermediate layer is made heat-sealable and a packaging container (for example, a tube) is made by sealing an envelope, the stretching ratio is preferably 2 times or more and 10 times or less, and more preferably 2.5 times or more and 7 times or less.

[0101] In one embodiment, it is preferable to stretch the intermediate layer so that its tensile strength in the longitudinal direction (MD direction) is greater than its tensile strength in the transverse direction (TD direction). By adopting this configuration, the packaging container made from the barrier laminate of the present invention can be given high ease of tearing in one direction. The tensile strength of the intermediate layer in the longitudinal direction (MD direction) is preferably 1.05 times greater than the tensile strength in the transverse direction (TD direction), more preferably 1.10 times greater, and even more preferably 1.2 times greater. The tensile strength in the longitudinal direction (MD direction) can be, for example, 200 MPa or more and 300 MPa or less. In this specification, tensile strength shall be measured in accordance with JIS K7127:1999. A tensile testing machine STA-1150 manufactured by Orientec Co., Ltd. can be used as the measuring instrument. As the test specimen, a rectangular film cut from the intermediate layer with a width of 15 mm and a length of 150 mm can be used. The distance between the pair of chucks holding the test specimen at the start of measurement is 100 mm, and the tensile speed is 300 mm / min. In this application, unless otherwise specified, the environment during tensile strength measurement is a temperature of 23°C and a relative humidity of 50%.

[0102] Furthermore, the surface resin layer of the intermediate layer may be surface-treated. This can improve adhesion with adjacent layers. The surface treatment method is not particularly limited and includes physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, glow discharge treatment, and chemical treatments such as oxidation treatment using chemicals.

[0103] (Surface resin layer) The intermediate layer comprises a surface protective layer on a polypropylene resin layer containing a resin material having a melting point of 180°C or higher (hereinafter also referred to as a high-melting-point resin material), and a vapor-deposited film with high adhesion can be formed on the surface resin layer, thereby improving gas barrier properties. Furthermore, as will be described later, packaging containers made using barrier laminates equipped with the surface resin layer have high lamination strength.

[0104] The melting point of the high-melting-point resin material is more preferably 185°C or higher, even more preferably 190°C or higher, and particularly preferably 205°C or higher. By setting the melting point of the high-melting-point resin material to 185°C or higher, the adhesion of the vapor-deposited film can be further improved, and the gas barrier properties can be enhanced. Furthermore, the lamination strength of the packaging container can be improved. From the viewpoint of film-forming properties of the intermediate layer, the melting point of the high-melting-point resin material is preferably 265°C or lower, more preferably 260°C or lower, and even more preferably 250°C or lower. In this specification, the melting point can be measured in accordance with JIS K7121:2012 (Method for measuring the transition temperature of plastics). Specifically, the melting point can be determined by measuring the DSC curve using a differential scanning calorimetry (DSC) device at a heating rate of 10°C / min.

[0105] The difference between the melting point of the high-melting-point resin material contained in the surface resin layer and the melting point of the polypropylene contained in the polypropylene resin layer is preferably 20 to 80°C, and more preferably 20 to 60°C. By ensuring that the difference between the melting point of the high-melting-point resin material in the surface resin layer and the melting point of the polypropylene in the polypropylene resin layer is 20°C or more, the adhesion of the vapor-deposited film can be further improved, and the gas barrier properties can be further enhanced. Furthermore, the lamination strength of the packaging container can be further improved. Furthermore, by ensuring that the difference between the melting point of the high-melting-point resin material contained in the intermediate layer and the melting point of the polypropylene contained in the polypropylene resin layer is 80°C or less, the film-forming properties of the intermediate layer can be further improved.

[0106] High-melting-point resin materials preferably have polar groups. In the present invention, a polar group refers to a group containing one or more heteroatoms, and examples include ester groups, epoxy groups, hydroxyl groups, amino groups, amide groups, carboxyl groups, carbonyl groups, carboxylic acid anhydride groups, sulfone groups, thiol groups, and halogen groups. Among these, hydroxyl groups, ester groups, amino groups, amide groups, carboxyl groups, and carbonyl groups are preferred from the viewpoint of gas barrier properties and lamination strength of the packaging container, with amide groups being more preferred.

[0107] High-melting-point resin materials can be used without particular limitations as long as their melting point is 180°C or higher. Examples include vinyl resins, polyamides, polyimides, polyesters, (meth)acrylic resins, cellulose resins, polyolefin resins, and ionomer resins.

[0108] In the present invention, resin materials having a melting point of 180°C or higher and having polar groups are particularly preferred, and polyamides such as ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, MXD nylon, and amorphous nylon are preferred, with nylon 6 being particularly preferred. By using such resin materials, the adhesion of the vapor-deposited film formed on the surface resin layer can be significantly improved, and its gas barrier properties can be effectively enhanced.

[0109] In one embodiment, the high-melting-point resin material is more preferably an ethylene vinyl alcohol copolymer. By using an ethylene vinyl alcohol copolymer as the high-melting-point resin material, the decrease in gas barrier properties can be suppressed even when the barrier laminate is bent.

[0110] In one embodiment, polyamide is preferred as the high-melting-point resin material. By using polyamide as the high-melting-point resin material, the decrease in gas barrier properties can be suppressed even when the barrier laminate is bent, and the decrease in gas barrier properties can be suppressed even when heating such as heat sealing is performed when manufacturing a packaged product using the barrier laminate. Nylon 6 is more preferred as the high-melting-point resin material.

[0111] The content of the high-melting-point resin material in the surface resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0112] Within the limits that do not impair the properties of the present invention, the surface resin layer may contain resin materials other than high-melting-point resin materials. Furthermore, within the limits that do not impair the properties of the present invention, the surface resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, lubricants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0113] The ratio of the thickness of the surface resin layer to the total thickness of the intermediate layer is preferably 1% to 10%, and more preferably 1% to 5%. By setting the ratio of the surface resin layer thickness to the total thickness of the intermediate layer to 1% or more, the adhesion of the vapor-deposited film can be further improved, and the gas barrier properties can be enhanced. Furthermore, the lamination strength of the packaging container can be further improved. Furthermore, by setting the ratio of the surface resin layer thickness to the total thickness of the intermediate layer to 10% or less, the film-forming properties and processability of the intermediate layer can be further improved. In addition, the recyclability of packaging containers made using laminates comprising a base material and sealant layer composed of polypropylene can be improved.

[0114] The thickness of the surface resin layer is preferably 0.1 μm or more and 5 μm or less, and more preferably 0.1 μm or more and 4 μm or less. By increasing the thickness of the surface resin layer to 0.1 μm or more, the adhesion of the vapor-deposited film can be further improved, thereby enhancing the gas barrier properties. Furthermore, the lamination strength of the packaging container can be improved. Furthermore, by making the thickness of the surface resin layer 5 μm or less, the film-forming properties and processability of the intermediate layer material can be further improved. In addition, the recyclability of packaging containers made using laminates comprising a base material and a sealant layer composed of polypropylene can be improved.

[0115] (Polypropylene resin layer) The polypropylene resin layer is made of polypropylene and may have a single-layer structure or a multi-layer structure. By including an intermediate layer made of polypropylene, it becomes possible to improve the oil resistance of packaging containers made using a barrier laminate having this intermediate layer.

[0116] The polypropylene contained in the polypropylene resin layer may be a homopolymer, a random copolymer, or a block copolymer. Polypropylene homopolymer is a polymer consisting solely of propylene; polypropylene random copolymer is a random copolymer of propylene and other α-olefins other than propylene (e.g., ethylene, butene-1, 4-methyl-1-pentene, etc.); and polypropylene block copolymer is a copolymer having polymer blocks made of propylene and polymer blocks made of the aforementioned α-olefins other than propylene. Among these polypropylenes, homopolymers or random copolymers are preferable from the viewpoint of transparency. When rigidity and heat resistance of the packaging bag are important, homopolymers are preferable, while when impact resistance and other factors are important, random copolymers are preferable. Additionally, biomass-derived polypropylene or mechanically or chemically recycled polypropylene can be used.

[0117] The polypropylene content in the polypropylene resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0118] Within the limits that do not impair the properties of the present invention, the polypropylene resin layer may contain resin materials other than polypropylene, such as polyolefins such as polyethylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamide resins, polyesters, and ionomer resins. Furthermore, within the limits that do not impair the properties of the present invention, the polypropylene resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, lubricants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0119] The thickness of the polypropylene resin layer is preferably 10 μm or more and 50 μm or less, and more preferably 10 μm or more and 40 μm or less. By increasing the thickness of the polypropylene resin layer to 10 μm or more, the strength and heat resistance of the intermediate layer can be further improved. Furthermore, by setting the thickness of the polypropylene resin layer to 50 μm or less, the film-forming properties and processability of the intermediate layer can be further improved.

[0120] (adhesive resin layer) In one embodiment, the intermediate layer may include an adhesive resin layer between the polypropylene resin layer and the surface resin layer, thereby improving the adhesion between these layers.

[0121] The adhesive resin layer can be formed by using adhesive resins such as polyethers, polyesters, silicone resins, epoxy resins, polyurethanes, vinyl resins, phenolic resins, polyolefins, and acid-modified polyolefins. Among those mentioned above, polyolefins and their acid-modified products are preferred, and polypropylene and its acid-modified products are particularly preferred, from the viewpoint of the recyclability of packaging containers made using laminates comprising a base material and a sealant layer composed of polypropylene. Commercially available adhesive polypropylene can be used; for example, the Admer series manufactured by Mitsui Chemicals, Inc. can be used.

[0122] The thickness of the adhesive resin layer is not particularly limited, but for example, it can be between 1 μm and 15 μm. By making the adhesive resin layer 1 μm or thicker, the adhesion between the polypropylene resin layer and the surface resin layer can be further improved. By making the adhesive layer 15 μm or less thick, the processability of the intermediate layer can be improved.

[0123] In one embodiment, the intermediate layer is a co-extruded film, which can be produced by forming a laminated film using a T-die method or an inflation method, and then stretching it. By forming the film using the inflation method, the stretching of the laminated film can be performed simultaneously.

[0124] (Sealant layer) In one embodiment, the sealant layer includes a resin material that can fuse with itself upon heat. Examples of resin materials that can fuse with each other by heat include polyolefins such as polyethylene, polypropylene, polybutene, methylpentene polymers, and cyclic olefin copolymers. Specifically, these include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), ethylene-α-olefin copolymers polymerized using metallocene catalysts, and ethylene-propylene copolymers such as random or block copolymers of ethylene and propylene. Furthermore, examples of resin materials that can fuse with each other by heat include ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ionomer resins, heat-sealable ethylene-vinyl alcohol resins, acid-modified polyolefins obtained by modifying polyolefins with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and itaconic acid, polyesters such as polyethylene terephthalate (PET), polyvinyl acetate resins, poly(meth)acrylic resins, and polyvinyl chloride resins. Among the resin materials described above, from the viewpoint of the recyclability of packaging containers made using the barrier laminate of the present invention, the sealant layer is preferably made of polypropylene. Furthermore, by constructing the sealant layer from polypropylene, the oil resistance of packaging containers made using barrier laminates can be improved.

[0125] The sealant layer may contain a heat seal modifier, which can improve its heat sealability. The heat seal modifier is not particularly limited as long as it has good compatibility with the resin material constituting the heat seal layer, such as polypropylene, but examples include olefin copolymers. Furthermore, the sealant layer may contain the above-mentioned additives, to the extent that it does not impair the properties of the present invention.

[0126] The sealant layer may have a single-layer structure or a multi-layer structure. Furthermore, the sealant layer may be stretched or not.

[0127] The thickness of the sealant layer is preferably 15 μm to 100 μm, and more preferably 20 μm to 70 μm. By making the sealant layer thickness 15 μm or more, the laminate strength of the packaging container equipped with the barrier laminate of the present invention can be further improved. Furthermore, by making the thickness of the sealant layer 100 μm or less, the processability of the barrier laminate of the present invention can be further improved.

[0128] In one embodiment, the sealant layer is made of a film composed of the above-mentioned resin material, and can be formed by laminating it with an intermediate layer and the above-mentioned adhesive layer. In another embodiment, the sealant layer can be formed by applying and drying a heat sealant containing the resin material onto the intermediate layer.

[0129] (Barrier coat layer) The barrier laminate of the present invention may further include a barrier coating layer between the adhesive layer and the vapor-deposited film. This improves the oxygen barrier and water vapor barrier properties of the barrier laminate.

[0130] In one embodiment, the barrier coat layer includes polyamides such as ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyacrylonitrile, nylon 6, nylon 6,6 and polymethaxylylene adipamide (MXD6), polyester, polyurethane, and gas barrier resins such as (meth)acrylic resin. Among these, polyvinyl alcohol is preferred from the viewpoint of oxygen barrier properties and water vapor barrier properties. Furthermore, by incorporating polyvinyl alcohol into the barrier coating layer, the occurrence of cracks in the vapor-deposited film can be effectively prevented.

[0131] The gas barrier resin content in the barrier coat layer is preferably 50% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 90% by mass or less. By setting the gas barrier resin content in the barrier coat layer to 50% by mass or more, the oxygen barrier properties and water vapor barrier properties can be further improved.

[0132] The barrier coating layer may contain the above-mentioned additives to the extent that they do not impair the properties of the present invention.

[0133] The thickness of the barrier coat layer is preferably 0.01 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less. By making the barrier coat layer thickness 0.01 μm or more, the oxygen barrier and water vapor barrier properties of the barrier laminate can be further improved. By making the barrier coat layer thickness 10 μm or less, the processability of the barrier laminate can be improved. In addition, the recyclability of packaging containers made using laminates comprising a base material and sealant layer composed of polypropylene can be improved.

[0134] The barrier coating layer can be formed by dissolving or dispersing the above-mentioned gas barrier resin in water or a suitable solvent, applying it, and drying it. Alternatively, the barrier coating layer can also be formed by applying and drying a commercially available barrier coating agent.

[0135] In another embodiment, the barrier coating layer is a gas barrier coating film containing at least one resin composition, such as a hydrolyzed metal alkoxide or a hydrolyzed condensate of a metal alkoxide, obtained by polycondensation of a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method in the presence of a sol-gel catalyst, water, and an organic solvent. By providing such a barrier coating layer on the vapor-deposited film, the occurrence of cracks in the vapor-deposited film can be effectively prevented.

[0136] In one embodiment, the metal alkoxide is represented by the following general formula. R 1 n M(OR 2 ) m (However, in the formula, R 1 , R 2Each represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents the valence of M.)

[0137] As the metal atom M, for example, silicon, zirconium, titanium, aluminum, etc. can be used.) Also, R 1 and R 2 Examples of the organic group represented by include alkyl groups such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group and i-butyl group.)

[0138] Examples of the metal alkoxide satisfying the above general formula include tetramethoxysilane (Si(OCH3)4), tetraethoxysilane (Si(OC2H5)4), tetrapropoxysilane (Si(OC3H7)4), tetrabutoxysilane (Si(OC4H9)4), etc.)

[0139] Also, it is preferable to use a silane coupling agent together with the above metal alkoxide.) As the silane coupling agent, known organoalkoxysilanes containing organic reactive groups can be used, and in particular, organoalkoxysilanes having an epoxy group are preferable. Examples of the organoalkoxysilane having an epoxy group include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc.)

[0140] Two or more kinds of the above silane coupling agents may be used, and the silane coupling agent is preferably used in the range of about 1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the above metal alkoxide.)

[0141] As water-soluble polymers, polyvinyl alcohol and ethylene-vinyl alcohol copolymers are preferred, and from the viewpoint of oxygen barrier properties, water vapor barrier properties, water resistance and weather resistance, it is preferable to use these in combination.

[0142] The content of the water-soluble polymer in the gas barrier coating film is preferably 5 parts by mass or more and 500 parts by mass or less per 100 parts by mass of metal alkoxide. By setting the content of the water-soluble polymer in the gas barrier coating film to 5 parts by mass or more per 100 parts by mass of metal alkoxide, the oxygen barrier and water vapor barrier properties of the barrier laminate can be further improved. Furthermore, by setting the content of the water-soluble polymer in the gas barrier coating film to 500 parts by mass or less per 100 parts by mass of metal alkoxide, the film-forming properties of the gas barrier coating film can be improved.

[0143] In a gas barrier coating film, the ratio of metal alkoxide to water-soluble polymer (metal alkoxide / water-soluble polymer) is preferably 4.5 or less by mass, more preferably 1.0 to 4.5, and even more preferably 1.7 to 3.5. By setting the ratio of metal alkoxide to water-soluble polymer to 4.5 or less, the decrease in gas barrier properties can be suppressed even when the barrier laminate is bent. By setting the ratio of metal alkoxide to water-soluble polymer to 1.0 or higher, the decrease in gas barrier properties can be suppressed even when heating, such as by heat sealing, is performed when manufacturing packaging products using barrier laminates. Note that the above ratios represent the ratio of solid content.

[0144] The surface of the gas barrier coating film preferably has a silicon atom to carbon atom ratio (Si / C) of 1.60 or less, more preferably 0.50 to 1.60, and even more preferably 0.90 to 1.35, as measured by X-ray photoelectron spectroscopy (XPS). By keeping the ratio of silicon atoms to carbon atoms below 1.60, the decrease in gas barrier properties can be suppressed even when the barrier laminate is bent. By setting the ratio of silicon atoms to carbon atoms to 0.50 or higher, the reduction in gas barrier properties can be suppressed even when heating, such as by heat sealing, is performed when manufacturing packaging products using barrier laminates. The above range for the ratio of silicon atoms to carbon atoms can be achieved by appropriately adjusting the ratio of metal alkoxides to water-soluble polymers. In this specification, the ratio of silicon atoms to carbon atoms is expressed on a molar basis.

[0145] The ratio of silicon atoms to carbon atoms can be measured by narrow-scan analysis under the following measurement conditions using X-ray photoelectron spectroscopy (XPS). (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectrum acquisition conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): Approximately 6 mmφ Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ionic species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching area: 10mmφ Ion sputtering was performed for 30 seconds + 30 seconds + 60 seconds (total 120 seconds), and the spectrum was collected.

[0146] The thickness of the gas barrier coating film is preferably 0.01 μm to 100 μm, and more preferably 0.1 μm to 50 μm. This allows for improved oxygen barrier and water vapor barrier properties while maintaining recyclability. By setting the thickness of the gas barrier coating film to 0.01 μm or more, the oxygen barrier and water vapor barrier properties of the barrier laminate can be improved. Furthermore, the occurrence of cracks in the vapor-deposited film can be prevented. By setting the thickness of the gas barrier coating film to 100 μm or less, the recyclability of packaging containers made using a laminate of the barrier laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0147] A gas barrier coating film can be formed by applying a composition containing the above-mentioned materials using conventionally known methods such as roll coating (including gravure roll coaters), spray coating, spin coating, dipping, brushing, barcode application, or applicator application, and then polycondensing the composition by a sol-gel method. Suitable catalysts for the sol-gel process include acids or amine compounds. Suitable amine compounds are tertiary amines that are substantially insoluble in water and soluble in organic solvents, such as N,N-dimethylbenzylamine, tripropylamine, tributylamine, and tripentylamine. Among these, N,N-dimethylbenzylamine is preferred. The sol-gel catalyst is preferably used in an amount of 0.01 parts by mass or more and 1.0 part by mass or less per 100 parts by mass of metal alkoxide, and more preferably in an amount of 0.03 parts by mass or more and 0.3 parts by mass or less. The catalytic effect of the sol-gel method catalyst can be improved by using 0.01 parts by mass or more per 100 parts by mass of metal alkoxide. Furthermore, by using 1.0 part by mass or less per 100 parts by mass of metal alkoxide, the thickness of the formed gas barrier coating film can be made uniform.

[0148] The above composition may further contain an acid. The acid is used as a catalyst for the sol-gel process, mainly as a catalyst for the hydrolysis of metal alkoxides and silane coupling agents. Examples of acids used include mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid, as well as organic acids such as acetic acid and tartaric acid. The amount of acid used is preferably 0.001 moles or more and 0.05 moles or less relative to the total molar amount of the metal alkoxide and the alkoxide portion (e.g., silicate portion) of the silane coupling agent. By using an amount of acid equal to 0.001 moles or more relative to the total molar amount of the alkoxide component (e.g., silicate portion) of the metal alkoxide and silane coupling agent, the catalytic effect can be improved. Furthermore, by using an amount of acid equal to 0.05 moles or less relative to the total molar amount of the alkoxide component (e.g., silicate portion) of the metal alkoxide and silane coupling agent, the thickness of the formed gas barrier coating film can be made uniform.

[0149] Furthermore, the above composition preferably contains water in an amount of 0.1 moles to 100 moles, more preferably 0.8 moles to 2 moles, per mole of the total molar amount of metal alkoxide. By setting the water content to 0.1 moles or more per mole of total molar amount of metal alkoxide, the oxygen barrier and water vapor barrier properties of the barrier laminate of the present invention can be improved. Furthermore, by setting the water content to 100 moles or less per mole of total molar amount of alkoxide, the hydrolysis reaction can be carried out rapidly.

[0150] Furthermore, the above composition may contain an organic solvent. Examples of organic solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, and n-butanol.

[0151] The following describes one embodiment of a method for forming a gas barrier coating film. First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and, if necessary, a silane coupling agent. A polycondensation reaction gradually proceeds within this composition. Next, the composition is applied to the vapor-deposited film and dried using the conventionally known method described above. This drying further promotes the polycondensation reaction between the metal alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains one), forming a layer of composite polymer. Finally, a gas barrier coating film can be formed by heating the composition, for example, at a temperature of 20 to 250°C, preferably 50 to 220°C, for 1 second to 10 minutes.

[0152] The barrier coat layer may have a printed layer formed on its surface. The method for forming the printed layer is as described above.

[0153] (Barrier laminate in the second embodiment) As shown in Figure 8, the barrier laminate 20 of the present invention comprises a substrate 21, an adhesive layer 22, a vapor-deposited film 23, an intermediate layer 24, and a sealant layer 25, the intermediate layer 24 comprising a coating layer 26 and a polypropylene resin layer 27. In one embodiment, the barrier laminate 20 of the present invention further comprises a barrier coating layer 28 between the adhesive layer 22 and the vapor-deposited film 23, as shown in Figure 9.

[0154] In the barrier laminate according to the second embodiment, the laminate strength between the intermediate layer and the vapor-deposited film is preferably 3N or more, more preferably 4N or more, and even more preferably 5.5N or more, with a width of 15 mm. The upper limit of the laminate strength of the barrier laminate according to the second embodiment may be 20N or less. The method for measuring the laminate strength of the barrier laminate will be explained in the examples described later.

[0155] Similar to the first embodiment, it is preferable that the base material and sealant base material be made of the same material as the polypropylene resin layer in the intermediate layer, i.e., polypropylene. This improves the recyclability of the packaging container made using the barrier laminate of the present invention.

[0156] When the base material and sealant layer are made of polypropylene, the polypropylene content relative to the total amount of resin material contained in the barrier laminate of the present invention is preferably 80% by mass or more, and more preferably 95% by mass or more. This makes it possible to further improve the recyclability of packaging containers made using the barrier laminate of the present invention.

[0157] The intermediate layer of the barrier laminate of the present invention will be described below. Note that the layers other than the intermediate layer in the barrier laminate of the second embodiment are the same as those in the barrier laminate of the first embodiment, and therefore will not be described here.

[0158] (Middle class) The intermediate layer comprises a surface coating layer and a polypropylene resin layer.

[0159] (Surface coating layer) The intermediate layer comprises a surface coating layer containing a resin material having polar groups on a polypropylene resin layer, and a vapor-deposited film with high adhesion can be formed on the surface coating layer, thereby improving gas barrier properties. Furthermore, as will be described later, packaging containers made using barrier laminates equipped with a surface coating layer have high lamination strength.

[0160] The surface coating layer contains a resin material having polar groups. In the present invention, a polar group refers to a group containing one or more heteroatoms, such as ester groups, epoxy groups, hydroxyl groups, amino groups, amide groups, carboxyl groups, carbonyl groups, carboxylic acid anhydride groups, sulfone groups, thiol groups, and halogen groups. Among these, from the viewpoint of the lamination properties of the packaging container, carboxyl groups, carbonyl groups, ester groups, hydroxyl groups, and amino groups are preferred, with carboxyl groups and hydroxyl groups being more preferred.

[0161] Preferred resin materials having polar groups include ethylene vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, polyamides such as nylon 6, nylon 6,6, MXD nylon, and amorphous nylon, and polyurethane, with polyamides, hydroxyl group-containing (meth)acrylic resin, ethylene vinyl alcohol copolymer, and polyvinyl alcohol being particularly preferred. By using such resin materials, the adhesion of the vapor-deposited film formed on the surface coating layer can be significantly improved, and its gas barrier properties can be effectively enhanced.

[0162] In the present invention, the surface coating layer can be formed using an aqueous emulsion or a solvent-based emulsion. Specific examples of aqueous emulsions include polyamide emulsions, polyethylene emulsions, polyurethane emulsions, etc., while specific examples of solvent-based emulsions include polyester emulsions, etc.

[0163] The content of the resin material having polar groups in the surface coating layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0164] Within the limits that do not impair the properties of the present invention, the surface coating layer may contain resin materials other than resin materials having polar groups. Furthermore, within the limits that do not impair the properties of the present invention, the surface coating layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, lubricants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0165] The ratio of the thickness of the surface coating layer to the total thickness of the intermediate layer is preferably 0.08% to 20%, more preferably 0.2% to 20%, even more preferably 1% to 20%, and even more preferably 3% to 10%. By setting the ratio of the surface coating layer thickness to the total thickness of the intermediate layer to 0.08% or more, the adhesion of the vapor-deposited film can be further improved, thereby enhancing the gas barrier properties. Furthermore, the lamination strength of the packaging container can be further improved. Furthermore, by setting the ratio of the surface coating layer thickness to the total thickness of the intermediate layer to 20% or less, the processability of the intermediate layer can be further improved. In addition, the recyclability of packaging containers made using laminates comprising a base material and a sealant layer composed of polypropylene can be improved.

[0166] The thickness of the surface coating layer is preferably 0.02 μm or more and 10 μm or less, more preferably 0.05 μm or more and 10 μm or less, more preferably 0.1 μm or more and 10 μm or less, and more preferably 0.2 μm or more and 5 μm or less. By increasing the thickness of the surface coating layer to 0.02 μm or more, the adhesion of the vapor-deposited film can be further improved, thereby enhancing its gas barrier properties. Furthermore, the lamination strength of the packaging container can be improved. Furthermore, by making the thickness of the surface coating layer 10 μm or less, the processability of the intermediate layer can be further improved. In addition, the recyclability of packaging containers made using laminates comprising a base material and a sealant layer composed of polypropylene can be improved.

[0167] (Polypropylene resin layer) The polypropylene resin layer is made of polypropylene and may have a single-layer structure or a multi-layer structure. By including an intermediate layer made of polypropylene, it becomes possible to improve the oil resistance of packaging containers made using a barrier laminate having this intermediate layer.

[0168] The polypropylene resin layer is a stretched film, and the stretching process may be uniaxial stretching or biaxial stretching. The stretching ratio in the longitudinal (MD direction) and transverse (TD direction) directions of the polypropylene resin layer is preferably 2 times or more and 15 times or less, and preferably 5 times or more and 13 times or less. By increasing the stretching ratio to 2 times or more, the strength and heat resistance of the polypropylene resin layer can be further improved. Furthermore, the printability of the polypropylene resin layer can be improved. Furthermore, from the viewpoint of the fracture limit of the polypropylene resin layer, it is preferable that the stretch ratio is 15 times or less.

[0169] The polypropylene contained in the polypropylene resin layer may be a homopolymer, a random copolymer, or a block copolymer. Polypropylene homopolymer is a polymer consisting solely of propylene; polypropylene random copolymer is a random copolymer of propylene and other α-olefins other than propylene (e.g., ethylene, butene-1, 4-methyl-1-pentene, etc.); and polypropylene block copolymer is a copolymer having polymer blocks made of propylene and polymer blocks made of the aforementioned α-olefins other than propylene. Among these polypropylenes, homopolymers or random copolymers are preferable from the viewpoint of transparency. When rigidity and heat resistance of the packaging bag are important, homopolymers are preferable, while when impact resistance and other factors are important, random copolymers are preferable. Additionally, biomass-derived polypropylene or mechanically or chemically recycled polypropylene can be used.

[0170] The polypropylene content in the polypropylene resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0171] Within the limits that do not impair the properties of the present invention, the polypropylene resin layer may contain resin materials other than polypropylene, such as polyolefins such as polyethylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamide resins, polyesters, and ionomer resins. Furthermore, within the limits that do not impair the properties of the present invention, the polypropylene resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, lubricants, ultraviolet absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0172] The thickness of the polypropylene resin layer is preferably 10 μm or more and 50 μm or less, and more preferably 10 μm or more and 40 μm or less. By increasing the thickness of the polypropylene resin layer to 10 μm or more, the strength and heat resistance of the intermediate layer can be further improved. Furthermore, by setting the thickness of the polypropylene resin layer to 50 μm or less, the film-forming properties and processability of the intermediate layer can be further improved.

[0173] Furthermore, the polypropylene resin layer may be surface-treated. This can improve adhesion with the surface coating layer. The surface treatment method is not particularly limited and includes physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, glow discharge treatment, and chemical treatments such as oxidation treatment using chemicals.

[0174] The intermediate layer can be manufactured offline. Specifically, it can be produced by forming a resin film from a polypropylene-containing resin composition using a T-die method or an inflation method, stretching the film, and then applying and drying a coating liquid for coating the resin film. Furthermore, the intermediate layer can also be manufactured in-line. Specifically, a resin composition containing polypropylene is formed into a film using a T-die method or inflation method, which is then stretched in the longitudinal direction (MD direction). A coating liquid for coating is applied to the resin film, dried, and then stretched in the transverse direction (TD direction). Note that the transverse stretching may be performed first.

[0175] (packaging container) The packaging container of the present invention is characterized by comprising the above-mentioned barrier laminate. Examples of packaging containers include packaged products (packaging bags), lid materials, and laminate tubes.

[0176] Examples of packaging bags include various types such as standing pouch type, side seal type, two-side seal type, three-side seal type, four-side seal type, envelope seal type, gusset seal type (pillow seal type), pleated seal type, flat bottom seal type, square bottom seal type, and gusset type.

[0177] As shown in Figure 10, the packaging container of the present invention is a packaging bag 30 formed by bonding two barrier laminates together (the shaded area is the heat-sealed portion). When the tensile strength of the intermediate layer in the longitudinal direction (MD direction) is greater than the tensile strength in the transverse direction (TD direction), it is preferable to manufacture the packaging bag such that the longitudinal direction (MD direction) of the intermediate layer corresponds to the transverse direction of the packaging bag 30, and the transverse direction (TD direction) of the intermediate layer corresponds to the longitudinal direction of the packaging bag 30. With this configuration, tearing the packaging container in the transverse direction becomes extremely easy. The same applies to the packaging containers exemplified below.

[0178] The packaging container of the present invention is a standing pouch 40, as shown in Figure 11. Figure 11 is a simplified diagram showing an example of the configuration of a standing pouch. As shown in Figure 11, the standing pouch 40 consists of a body (side sheet) 41 and a bottom (bottom sheet) 42. The side sheet 41 and bottom sheet 42 of the standing pouch 40 are made of the barrier laminate of the present invention, at least one of them being composed of the barrier laminate of the present invention.

[0179] In one embodiment, the body portion 41 of the standing pouch 40 can be formed by manufacturing the bag such that the sealant layer of the barrier laminate of the present invention becomes the innermost layer. In another embodiment, the side sheet 41 can be formed by preparing two barrier laminates of the present invention, overlapping them so that the sealant layers face each other, and inserting two V-shaped folded laminates from both ends of the overlapped barrier laminate so that the sealant layers face outwards, and then heat sealing them. According to this manufacturing method, a stand pouch having a body with side gussets can be made.

[0180] In one embodiment, the bottom sheet 42 of the standing pouch 40 can be formed by inserting the barrier laminate of the present invention between the side sheets of the bag and heat sealing it. More specifically, the barrier laminate can be formed by folding it in a V-shape so that the sealant layer is on the outside, inserting it between the side sheets of the bag, and heat sealing it.

[0181] Furthermore, the packaging container may be equipped with an easy-opening mechanism 51, as shown in Figure 10. Examples of the easy-opening means 51 include a notch portion 52 that serves as the starting point for tearing, as shown in Figure 10, and a half-cut line 53 formed by laser processing or a cutter as a path for tearing.

[0182] Furthermore, the packaging container may be equipped with a steam venting mechanism 60, as shown in Figure 11. The steam venting mechanism 60 is configured to allow steam to escape by connecting the inside and outside of the packaging container when the steam pressure inside the packaging container exceeds a predetermined value, while also preventing steam from escaping at locations other than the steam venting mechanism 60. The steam venting mechanism 50 includes a steam venting seal portion 60a that protrudes from the side seal portion toward the inside of the packaging container, and an unsealed portion 60b that is isolated from the contents storage portion by the steam venting seal portion 60a. The unsealed portion 60b is in communication with the outside of the packaging. When the packaging container, which is filled with contents and has its opening heat-sealed, is heated in a microwave oven or the like, the internal pressure increases, causing the steam seal portion 60a to peel off. The steam escapes through the peeled portion of the steam seal 60a and the unsealed portion 60b to the outside of the packaging container.

[0183] Heat sealing can be carried out using known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high-frequency sealing, and ultrasonic sealing.

[0184] The contents filled into the packaging container are not particularly limited and may be liquids, powders, or gels. They may also be food products or non-food products.

[0185] (Other forms) In another embodiment, the barrier laminate of the present invention comprises a substrate, an adhesive layer, a vapor-deposited film, an intermediate layer, and a sealant layer. The aforementioned intermediate layer comprises at least a surface resin layer and a polypropylene resin layer. The aforementioned surface resin layer contains a resin material with a melting point of 180°C or higher. The aforementioned deposited film is composed of an inorganic oxide, The surface resin layer and the polypropylene resin layer are characterized by having undergone stretching treatment. In one embodiment, the polypropylene resin layer, the substrate, and the sealant layer are made of the same material, and this same material is polypropylene. In one embodiment, the adhesive layer is an adhesive layer comprising a cured product of a composition containing a polyester polyol and an isocyanate compound. In one embodiment, the melting point of the resin material is 265°C or lower. In one embodiment, the difference between the melting point of the resin material and the melting point of the polypropylene contained in the polypropylene resin layer is 20 to 80°C. In one embodiment, the resin material has a polar group. In one embodiment, the resin material is one or more resin materials selected from ethylene vinyl alcohol copolymer, polyvinyl alcohol, nylon 6, nylon 6,6, MXD nylon, and amorphous nylon. In one embodiment, the resin material is polyamide. In one embodiment, the resin material is ethylene vinyl alcohol. In one embodiment, the ratio of the thickness of the surface resin layer to the total thickness of the intermediate layer is 1% or more and 10% or less. In one embodiment, the intermediate layer is a coextruded film.

[0186] In another aspect, the barrier laminate of the present invention includes a substrate, an adhesive layer, a vapor deposition film, an intermediate layer, and a sealant layer. The intermediate layer includes a surface coat layer and a polypropylene resin layer. The polypropylene resin layer is subjected to a stretching treatment. And the surface coat layer contains a resin material having a polar group. The vapor deposition film is composed of an inorganic oxide. In one embodiment, the polypropylene resin layer, the substrate, and the sealant layer are made of the same material, and the same material is polypropylene. In one embodiment, the adhesive layer is an adhesive layer containing a cured product of a composition of polyester polyol and an isocyanate compound. In one embodiment, the ratio of the thickness of the surface coat layer to the total thickness of the intermediate layer is 0.08% or more and 20% or less. In one embodiment, the thickness of the surface coat layer is 0.02 μm or more and 10 μm or less. In one embodiment, the resin material is one or more resin materials selected from ethylene vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, nylon 6, nylon 6,6, MXD nylon, amorphous nylon, and polyurethane. In one embodiment, the surface coating layer is a layer formed using an aqueous emulsion or a solvent-based emulsion. In one embodiment, the barrier laminate of the present invention further comprises a barrier coating layer between the adhesive layer and the vapor-deposited film. In one embodiment, the barrier laminate of the present invention is used for packaging container applications.

[0187] Another embodiment of the present invention is a packaging container characterized by comprising the above-mentioned barrier laminate. [Examples]

[0188] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0189] Example 1-1 Polyamide (Polyamide 6, manufactured by Ube Industries, Ltd., melting point: 220°C), adhesive resin (Admer QF500, maleic anhydride-modified polypropylene, manufactured by Mitsui Chemicals, Inc.), and polypropylene (Novatec FL203D, manufactured by Nippon Polypropylene Co., Ltd., melting point: 160°C) were co-extruded, and then stretched five times in the longitudinal direction (MD direction) and ten times in the transverse direction (TD direction) using a sequential biaxial stretching apparatus to produce an intermediate layer with a thickness of 21 μm, comprising a surface resin layer made of polyamide (19.6 μm), an adhesive resin layer made of adhesive resin (1 μm), and a polypropylene resin layer made of polypropylene (0.4 μm). The ratio of the thickness of the surface resin layer made of polyamide to the thickness of the intermediate layer was 2%.

[0190] On the surface resin layer of the intermediate layer prepared as described above, a 12 nm thick carbon-containing silicon oxide vapor deposition film was formed using a real low-temperature plasma chemical vapor deposition apparatus (CVD) by Roll-to-Roll while applying tension to the intermediate layer. The vapor deposition film formation conditions were as follows. (Formation conditions) Hexamethyldisiloxane:Oxygen gas:Helium = 1:10:10 (unit: slm) • Cooling / electrode drum power supply: 22kW Line speed: 100m / min

[0191] In the carbon-containing silicon oxide vapor-deposited film, the proportions of carbon (C), silicon (Si), and oxygen (O) were 32.7%, 29.8%, and 37.5%, respectively, relative to the total of the three elements (silicon, oxygen, and carbon) (100%). The proportions of each element were measured by narrow-scan analysis using X-ray photoelectron spectroscopy (XPS) under the following measurement conditions. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectrum acquisition conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): Approximately 6 mmφ Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ionic species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching area: 10mmφ Ion sputtering was performed for 30 seconds, and the spectrum was collected.

[0192] 385 g of water, 67 g of isopropyl alcohol, and 9.1 g of 0.5 N hydrochloric acid were mixed to prepare a pH 2.2 solution. To this solution, 175 g of tetraethoxysilane as a metal alkoxide and 9.2 g of glycidoxypropyltrimethoxysilane as a silane coupling agent were mixed while cooling to 10°C to obtain solution A. Solution B was obtained by mixing 14.7 g of polyvinyl alcohol with a saponification value of 99% or higher and a degree of polymerization of 2400 as a water-soluble polymer, 324 g of water, and 17 g of isopropyl alcohol. Solution A and solution B were mixed in a ratio of 6.5:3.5 by mass to obtain a barrier coating agent.

[0193] A barrier coating agent was applied to a vapor-deposited film formed on an intermediate layer using a spin-coating method, and then heated in an oven at 80°C for 60 seconds to form a barrier coating layer with a thickness of 300 nm.

[0194] On the barrier coat layer formed as described above, a 3 μm thick adhesive layer was formed using an adhesive containing polyester polyol and isocyanate compound (DIC Corporation, product name: PASLIM VM001 / VM102CP (mixing ratio 1:1)), and a 20 μm thick stretched polypropylene film (Mitsui Chemicals Tohcello Co., Ltd., U1) was laminated as a substrate through this adhesive layer.

[0195] A 1 μm thick adhesive layer was formed on the intermediate polypropylene resin layer using a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1) manufactured by Mitsui Chemicals, Inc.), and a 30 μm thick unstretched polypropylene film (CP S manufactured by Mitsui Chemicals Tohcello Co., Ltd.) was laminated as a sealant layer via this adhesive layer to obtain the barrier laminate of the present invention. The polypropylene content in the barrier laminate was 92% by mass.

[0196] Examples 1-2 A barrier laminate was produced in the same manner as in Example 1-1, except that the sealant layer was changed to a heat-sealable biaxially stretched polypropylene film (manufactured by Toyo Corporation, P6181) with a thickness of 30 μm. The content of polypropylene in the barrier laminate was 9% by mass.

[0197] Examples 1-3 A barrier laminate of the present invention was obtained in the same manner as in Example 1-1, except that a polypropylene-based heat-sealing material (manufactured by Unitika Ltd., Arrow Base DA1010N) was applied and dried on the polypropylene resin layer of the intermediate layer to form a sealant layer with a thickness of 3 μm. The content of polypropylene in the barrier laminate was 82% by mass.

[0198] Examples 1-4 A barrier laminate was produced in the same manner as in Example 1-1, except that the polyamide used for producing the intermediate layer was changed to polyvinyl alcohol (manufactured by Nippon Gohsei-Bopar Co., Ltd., Bopar JC-33, melting point: 200 °C) and the surface resin layer was formed.

[0199] Example 2-1 On the corona-treated surface of a biaxially stretched polypropylene film (manufactured by Mitsui Chemicals Toagosei Co., Ltd., ME-1) with a thickness of 20 μm and one surface corona-treated, a solution for forming a surface coat layer having the following composition was applied and dried to form a surface coat layer with a thickness of 0.5 μm, and an intermediate layer was produced. (Composition of the coating liquid for forming the surface coat layer) · Polyvinyl alcohol 5% by mass (manufactured by Nippon Gohsei-Bopar Co., Ltd., VC-10, degree of polymerization 1000, saponification degree 99.3 mol% or more) · Water 90% by mass · Isopropanol (IPA) 5% by mass

[0200] A barrier laminate was produced in the same manner as in Example 1-1, except that the intermediate layer produced in Example 1-1 was changed to the intermediate layer produced as described above. The polypropylene content in the barrier laminate was 93% by mass.

[0201] Example 2-2 A barrier laminate was prepared in the same manner as in Example 2-1, except that the composition of the coating liquid for forming the surface coating layer was changed as follows. The polypropylene content in the barrier laminate was 93% by mass. (Composition of coating liquid for surface coating layer formation) ·EVOH 75% by mass (Manufactured by Nippon Seema Co., Ltd., Eversolve #10) ·Water 12.5% ​​by mass • 1-Propanol 12.5% ​​by mass

[0202] Comparative Example 1-1 After extruding the above-mentioned polypropylene (Novatec FL203D, manufactured by Nippon Polypropylene Co., Ltd., melting point: 160°C), a propylene film with a thickness of 20 μm was produced by sequentially stretching it five times in the longitudinal direction (MD direction) and ten times in the transverse direction (TD direction) using a biaxial stretching apparatus. A barrier laminate was prepared in the same manner as in Example 1-1, except that the intermediate layer in Example 1-1 was replaced with a polypropylene film prepared as described above.

[0203] <<Gas Barrier Properties Evaluation>> The barrier laminates obtained in the above examples and comparative examples were cut out to obtain test specimens. Using these test specimens, the oxygen permeability (cc / m³) was measured. 2 (day·atm) and water vapor transmission (g / m³) 2 The following method was used to measure the (day) and the results are summarized in Table 1.

[0204] [Oxygen permeability] Using an oxygen permeability measuring device (MOCON, OX-TRAN2 / 20), the test specimen was set up so that the substrate side was facing the oxygen supply side, and the oxygen permeability was measured in accordance with JIS K 7126 under conditions of 23°C and 90% RH relative humidity. [Water vapor transmission rate] Using a water vapor transmission rate measuring device (MOCON, PERMATRAN-w 3 / 33), the test specimen was set up so that the substrate side was facing the water vapor supply side, and the water vapor transmission rate was measured in accordance with JIS K 7129 under conditions of 40°C and 90% RH relative humidity.

[0205] <<Laminate Strength Test>> Samples of the barrier laminates obtained in the above examples and comparative examples were cut into 15 mm wide strips. The laminate strength (N / 15 mm) was measured using a tensile testing machine (Tensilon Universal Material Tester, manufactured by Orientec Co., Ltd.) in accordance with JIS K6854-2, with a peeling speed of 50 mm / min and a 90° peeling (T-peeling method). Specifically, first, a barrier laminate was cut out, and as shown in Figure 12, a strip-shaped test piece 70 was prepared by peeling off the base material side 71 and the sealant layer side 72 by 15 mm in the long-side direction. Then, as shown in Figure 13, the already peeled portions of the base material side 71 and the sealant layer side 72 were gripped with the grips 73 of the measuring instrument. The grips 73 were each pulled at a speed of 50 mm / min in opposite directions perpendicular to the plane direction of the portion where the base material side 71 and the sealant layer side 72 were still laminated, and the average value of the tensile stress in the stable region (see Figure 14) was measured. The distance S between the grips 73 at the start of pulling was 30 mm, and the distance S between the grips 73 at the end of pulling was 60 mm. Figure 14 is a diagram showing the change in tensile stress with respect to the distance S between the grips 73. As shown in Figure 14, the change in tensile stress with respect to the distance S goes through the first region and enters the second region (stable region), which has a smaller rate of change than the first region. For 70 test specimens (5 specimens), the average tensile stress in the stable region was measured, and this average value was defined as the laminate strength. The measurement environment was 23°C and 50% relative humidity. The measurement results are summarized in Table 1.

[0206] [Table 1]

[0207] Reference example 1-1 A 21 μm thick substrate was prepared by co-extruding polyamide (Polyamide 6, manufactured by Ube Industries, Ltd., melting point: 220°C), adhesive resin (Admer QF500, maleic anhydride-modified polypropylene, manufactured by Mitsui Chemicals, Inc.), and polypropylene (Novatec FL203D, manufactured by Nippon Polypropylene Co., Ltd., melting point: 160°C). The substrate was then stretched five times in the longitudinal direction (MD direction) and ten times in the transverse direction (TD direction) using a sequential biaxial stretching apparatus to produce a 21 μm thick substrate comprising a surface resin layer made of polyamide (19.6 μm), an adhesive resin layer made of adhesive resin (1 μm), and a polypropylene resin layer made of polypropylene (0.4 μm). The ratio of the thickness of the surface resin layer made of polyamide to the total thickness of the substrate was 2%.

[0208] On the surface resin layer of the substrate prepared as described above, a 12 nm thick carbon-containing silicon oxide vapor deposition film was formed using a low-temperature plasma chemical vapor deposition apparatus (CVD) by applying tension to the substrate via a roll-to-roll method. The vapor deposition film formation conditions were as follows. (Formation conditions) Hexamethyldisiloxane:Oxygen gas:Helium = 1:10:10 (unit: slm) • Cooling / electrode drum power supply: 22kW Line speed: 100m / min

[0209] In the carbon-containing silicon oxide vapor-deposited film, the proportions of carbon (C), silicon (Si), and oxygen (O) were 32.7%, 29.8%, and 37.5%, respectively, relative to the total of the three elements (silicon, oxygen, and carbon) (100%). The proportions of each element were measured by narrow-scan analysis using X-ray photoelectron spectroscopy (XPS) under the following measurement conditions. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectrum acquisition conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): Approximately 6 mmφ Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ionic species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching area: 10mmφ Ion sputtering was performed for 30 seconds, and the spectrum was collected.

[0210] A barrier coat layer was formed on the vapor-deposited film such that the solid content ratio of metal alkoxide to water-soluble polymer (metal alkoxide / water-soluble polymer) was 5.1 by mass.

[0211] The ratio of Si to C elements present on the barrier coat layer surface was measured. The measurement was performed using X-ray photoelectron spectroscopy (XPS) with narrow-scan analysis under the measurement conditions described below. In the reference examples below, the ratio of Si to C elements present on the barrier coat layer surface was measured in the same manner. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectrum acquisition conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): Approximately 6 mmφ Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ionic species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching area: 10mmφ Ion sputtering was performed for 30 seconds + 30 seconds + 60 seconds (total 120 seconds), and the spectrum was collected.

[0212] Next, a 60 μm thick unstretched polypropylene film (Toyobo Co., Ltd., P1128) was dry-laminated onto the barrier coat layer using a two-component curing polyurethane adhesive to form a sealant layer and obtain a barrier laminate.

[0213] Reference example 1-2 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0214] Reference example 1-3 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0215] Reference example 1-4 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0216] Reference example 1-5 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0217] Reference example 1-6 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0218] Reference example 2-1 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the deposition film formation method was modified as follows. Using a continuous vapor deposition (PVD) system equipped with a pretreatment section containing an actual oxygen plasma pretreatment device and a film deposition section separated on a surface resin layer, the substrate was subjected to oxygen plasma pretreatment in the pretreatment section by applying tension to the substrate using a roll-to-roll method, while plasma was introduced from a plasma supply nozzle under the following conditions. In the film deposition section, the substrate was continuously transported, and a 12 nm thick aluminum oxide (alumina) vapor-deposited film was formed on the oxygen plasma-treated surface under the following conditions, using a reactive resistance heating method as the heating means for vacuum deposition (PVD method). (Formation conditions) (Oxygen plasma pretreatment conditions) Plasma intensity: 200W·sec / m 2 Plasma formation gas ratio: Oxygen:Argon = 2:1 • Voltage applied between pre-treatment drum and plasma supply nozzle: 340V (Film deposition conditions) • Conveying speed: 400 m / min • Oxygen gas supply: 20,000 sccm

[0219] Reference example 2-2 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0220] Reference example 2-3 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0221] Reference example 2-4 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0222] Reference example 2-5 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0223] Reference example 2-6 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0224] Reference example 3-1 A barrier laminate was fabricated in the same manner as in Reference Example 1-1, except that the polyamide was replaced with ethylene vinyl alcohol (EVAL F171B, manufactured by Kuraray Co., Ltd., melting point: 183°C) and a surface resin layer was formed.

[0225] Reference example 3-2 A barrier laminate was fabricated in the same manner as in Reference Example 3-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0226] Reference example 3-3 A barrier laminate was fabricated in the same manner as in Reference Example 3-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0227] Reference example 3-4 A barrier laminate was fabricated in the same manner as in Reference Example 3-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0228] Reference example 3-5 A barrier laminate was fabricated in the same manner as in Reference Example 3-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0229] Reference example 3-6 A barrier laminate was fabricated in the same manner as in Reference Example 3-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0230] Reference example 4-1 A barrier laminate was fabricated in the same manner as in Reference Example 2-1, except that the polyamide was replaced with ethylene vinyl alcohol (EVAL F171B, manufactured by Kuraray Co., Ltd., melting point: 183°C) and a surface resin layer was formed.

[0231] Reference example 4-2 A barrier laminate was fabricated in the same manner as in Reference Example 4-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0232] Reference example 4-3 A barrier laminate was fabricated in the same manner as in Reference Example 4-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0233] Reference example 4-4 A barrier laminate was fabricated in the same manner as in Reference Example 4-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0234] Reference example 4-5 A barrier laminate was fabricated in the same manner as in Reference Example 4-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0235] Reference example 4-6 A barrier laminate was fabricated in the same manner as in Reference Example 4-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0236] Reference example 5-1 A 20 μm thick biaxially oriented polypropylene film (ME-1, manufactured by Mitsui Chemicals Tohcello Co., Ltd.), with one side corona-treated, was coated with a surface coating solution prepared as described below, and dried to form a 0.5 μm thick surface coating layer, thereby creating a substrate.

[0237] A hydroxyl group-containing (meth)acrylic resin (number average molecular weight 25,000, glass transition temperature 99°C, hydroxyl value 80 mg KOHL / g) was diluted with a mixed solvent of methyl ketone and ethyl acetate (mixing ratio 1:1) until the solid content concentration reached 10% by mass to prepare the main component. An ethyl acetate solution containing tolylene diisocyanate (75% solids by mass) was added to the main component as a curing agent to obtain a coating liquid for forming a surface coating layer. The amount of curing agent used was 10 parts by mass per 100 parts by mass of the main component.

[0238] On the surface coating layer of the substrate prepared as described above, a 12 nm thick carbon-containing silicon oxide vapor deposition film was formed using a low-temperature plasma chemical vapor deposition apparatus (CVD) by applying tension to the substrate via a roll-to-roll method. The vapor deposition film formation conditions were as follows. (Formation conditions) Hexamethyldisiloxane:Oxygen gas:Helium = 1:10:10 (unit: slm) • Cooling / electrode drum power supply: 22kW Line speed: 100m / min

[0239] Next, a barrier coat layer was formed on the vapor-deposited film such that the solid content ratio of metal alkoxide to water-soluble polymer (metal alkoxide / water-soluble polymer) was 5.1 by mass.

[0240] Next, a 60 μm thick unstretched polypropylene film (Toyobo Co., Ltd., P1128) was dry-laminated onto the barrier coat layer using a two-component curing polyurethane adhesive to form a sealant layer and obtain a barrier laminate.

[0241] Reference example 5-2 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0242] Reference example 5-3 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0243] Reference example 5-4 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0244] Reference example 5-5 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0245] Reference example 5-6 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0246] Reference example 6-1 A third barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the deposition film formation method was modified as follows. A 20 nm thick silicon oxide (silica) vapor-deposited film was formed on the surface coating layer using a real induction heating vacuum deposition apparatus equipped with a plasma gun, applying tension to the multilayer substrate by roll-to-roll (PVD method). The vapor deposition film formation conditions were as follows. (Formation conditions) (Plasma irradiation conditions) • Line speed: 30m / min ·Vacuum degree: 1.7×10 -2 Pa Output: 5.7kW • Acceleration voltage: 151V Ar gas flow rate: 7.5 sccm (Film deposition conditions) • Deposition material: SiO • Reaction gas: O2 • Reaction gas flow rate: 100 sccm

[0247] Reference example 6-2 A barrier laminate was fabricated in the same manner as in Reference Example 6-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0248] Reference example 6-3 A barrier laminate was fabricated in the same manner as in Reference Example 6-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0249] Reference example 6-4 A barrier laminate was fabricated in the same manner as in Reference Example 6-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0250] Reference example 6-5 A barrier laminate was fabricated in the same manner as in Reference Example 6-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0251] Reference example 6-6 A barrier laminate was fabricated in the same manner as in Reference Example 6-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0252] Reference example 7-1 A barrier laminate was fabricated in the same manner as in Reference Example 5-1, except that the deposition film formation method was modified as follows.

[0253] Using a continuous vapor deposition (PVD) system equipped with a pretreatment section containing an actual oxygen plasma pretreatment device and a film deposition section separated on a surface coating layer, the system performed oxygen plasma pretreatment in the pretreatment section by applying tension to the multilayer substrate using a roll-to-roll method, introducing plasma from a plasma supply nozzle under the following conditions. In the film deposition section, which was then continuously transported, a 12 nm thick aluminum oxide (alumina) vapor-deposited film was formed on the oxygen plasma-treated surface under the following conditions, using a reactive resistance heating method as the heating means for vacuum deposition (PVD method). (Formation conditions) (Oxygen plasma pretreatment conditions) Plasma intensity: 200W·sec / m 2 Plasma formation gas ratio: Oxygen:Argon = 2:1 • Voltage applied between pre-treatment drum and plasma supply nozzle: 340V (Film deposition conditions) • Conveying speed: 400 m / min • Oxygen gas supply: 20,000 sccm

[0254] Reference example 7-2 A barrier laminate was fabricated in the same manner as in Reference Example 7-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0255] Reference example 7-3 A barrier laminate was fabricated in the same manner as in Reference Example 7-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0256] Reference example 7-4 A barrier laminate was fabricated in the same manner as in Reference Example 7-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0257] Reference example 7-5 A barrier laminate was fabricated in the same manner as in Reference Example 7-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0258] Reference example 7-6 A barrier laminate was fabricated in the same manner as in Reference Example 7-1, except that the barrier coat layer was formed such that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0259] <<Gas barrier properties evaluation (after lamination)>> A barrier laminate obtained in the above reference example was cut out to obtain a test specimen. Using this test specimen, the oxygen permeability (cc / m³) was measured in the same manner as described above. 2 (day·atm) and water vapor transmission (g / m³) 2 The following measurements were taken (day). The results are summarized in Tables 2-8. Note that the units for oxygen permeability and vapor permeability are omitted in Tables 2-8.

[0260] <<Gas barrier property evaluation (after Gelboflex test)>> Using the barrier layer obtained in the above reference example, a tubular bag was fabricated. Using this bag, the Gelboflex test in accordance with ASTM F392 was repeated 10 times. Subsequently, the barrier laminate was cut out from the bag to obtain a test specimen. Using this test specimen, the oxygen permeability (cc / m³) was measured in the same manner as described above. 2 (day·atm) and water vapor transmission (g / m³) 2 The following measurements were taken (day). The results are summarized in Tables 2-8. Note that the units for oxygen permeability and vapor permeability are omitted in Tables 2-8.

[0261] [Table 2]

[0262] [Table 3]

[0263] [Table 4]

[0264] [Table 5]

[0265] [Table 6]

[0266] [Table 7]

[0267] [Table 8] [Explanation of symbols]

[0268] 10: Barrier laminate, 11: Substrate, 12: Adhesive layer, 13: Vapor-deposited film, 14: Intermediate layer, 15: Sealant layer, 16: Surface resin layer, 17: Polypropylene resin layer, 18: Barrier coat layer, 19: Adhesive resin layer, 20: Barrier laminate, 21: Substrate, 22: Adhesive layer, 23: Vapor-deposited film, 24: Intermediate layer, 25: Sealant layer, 26: Surface coat layer, 27: Polypropylene resin layer, 28: Barrier coat layer, 30: Packaging bag, 40: Standing pouch, 41: Body (side sheet), 42: Bottom (bottom sheet), 51: Easy-open means, 52: Notch, 53: Half-cut line, 60 :Steam venting mechanism, 60a:Steam sealing section, 60b:Non-sealed section, 70:Test piece, 71:Substrate side, 72:Sealant layer side, 73:Gripping tool, A:Vacuum container, B:Unwinding section, C:Film formation drum, D:Winding section, E:Conveyor roll, F:Evaporation source, G:Reaction gas supply section, H:Anti-adhesion box, I:Deposition material, J:Plasma gun, A1:Vacuum container, B1:Unwinding section, C1:Cooling / electrode drum, D1:Winding section, E1:Conveyor roll, F1:Glow discharge plasma, G1:Reaction gas supply section, H1:Raw material supply nozzle, I1:Raw material gas supply section, J1:Magnet, K1:Power supply, L1:Vacuum pump

Claims

1. A barrier laminate comprising a substrate, an adhesive layer, a vapor-deposited film, an intermediate layer, and a sealant layer, The aforementioned intermediate layer comprises a surface coating layer and a polypropylene resin layer. The aforementioned polypropylene resin layer has been subjected to stretching treatment. Furthermore, the surface coating layer includes a resin material having polar groups, The barrier laminate comprises the vapor-deposited film on the surface coating layer, The aforementioned deposited film is composed of an inorganic oxide, The substrate and the sealant layer are made of polypropylene. A barrier laminate characterized in that the polypropylene content relative to the total amount of resin material contained in the barrier laminate is 80% by mass or more.

2. The barrier laminate according to claim 1, wherein the adhesive layer is an adhesive layer comprising a cured product of a composition containing a polyester polyol and an isocyanate compound.

3. The barrier laminate according to claim 1 or 2, wherein the ratio of the thickness of the surface coating layer to the total thickness of the intermediate layer is 0.08% or more and 20% or less.

4. The barrier laminate according to any one of claims 1 to 3, wherein the thickness of the surface coating layer is 0.02 μm or more and 10 μm or less.

5. The barrier laminate according to any one of claims 1 to 4, wherein the resin material is one or more resin materials selected from ethylene vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, nylon 6, nylon 6,6, MXD nylon, amorphous nylon, and polyurethane.

6. The barrier laminate according to any one of claims 1 to 5, wherein the surface coating layer is a layer formed using an aqueous emulsion or a solvent-based emulsion.

7. The barrier laminate according to any one of claims 1 to 6, further comprising a barrier coat layer between the adhesive layer and the vapor-deposited film.

8. A barrier laminate according to any one of claims 1 to 7, used for packaging container applications.

9. A packaging container characterized by comprising a barrier laminate according to any one of claims 1 to 8.

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