Laminate

Abstract

To provide a laminate using paper, which has not only initial oil resistance but also sufficient oil resistance even after being bent.SOLUTION: A laminate has a structure in which at least a paper base material, an anchor coat layer, an aluminum vapor deposition layer, and an overcoat layer are laminated in this order.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a laminate and a packaging bag. [Background technology]

[0002] In many fields, such as food, beverages, medicines, and chemicals, packaging materials are used according to the contents. Packaging materials are required to have gas barrier properties that prevent the permeation of water vapor, which can cause deterioration of the contents. In addition, packaging materials are required to have oil resistance to prevent the oil contained in the contents from seeping out, depending on the contents.

[0003] In recent years, the momentum for a plastic-free society has been growing due to growing environmental awareness triggered by the problem of marine plastic waste. From the viewpoint of reducing the amount of plastic materials used, the use of paper instead of plastic materials has been considered in various fields. For example, Patent Document 1 below discloses a laminate in which a barrier layer is laminated on paper. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-69783 A Summary of the Invention [Problem to be solved by the invention]

[0005] Paper has the characteristic of being easy to process due to its crease retention (also called dead-hold property). However, according to the study by the present inventors, it was found that there is still room for improvement in that cracks occur in the barrier layer and oil resistance decreases when paper is used for packaging bags with sharper creases (pillow packaging, three-side seal packaging, and gusset packaging).

[0006] Moreover, from the viewpoint of the Law for Promoting Effective Utilization of Resources, it is required to reduce the amount of plastic materials used in laminates as well.

[0007] Therefore, an object of the present disclosure is to provide a laminate using paper that has sufficient oil resistance not only at the initial stage but also after being folded, and a packaging bag including the laminate. [Means for solving the problem]

[0008] In order to solve the above problems, the present disclosure provides the following laminate and packaging bag. [1] A laminate having a structure in which at least a paper base material, an anchor coat layer, an aluminum vapor deposition layer, and an overcoat layer are laminated in this order, and the aluminum vapor deposition layer has a half-width of the peak of the aluminum (111) crystal plane of 1.6° or more in X-ray diffraction measurement. [2] The laminate according to [1] above, wherein the anchor coat layer contains a polyolefin or polyvinyl alcohol resin having a polar group. [3] The laminate according to [1] or [2] above, wherein the overcoat layer contains a polyolefin having a polar group. [4] The laminate according to any one of the above [1] to [3], wherein the hardness of the anchor coat layer measured by nanoindentation in a cross section in the thickness direction of the laminate is 0.3 GPa or less. [5] The laminate according to any one of the above [1] to [4], wherein the hardness of the overcoat layer measured by nanoindentation in a cross section in the thickness direction of the laminate is 0.3 GPa or less. [6] The laminate according to any one of the above [1] to [5], wherein the thickness of the aluminum vapor deposition layer is 20 nm or more and 100 nm or less. [7] The laminate according to any one of the above [1] to [6], wherein the aluminum vapor deposition layer has a half-width of the peak of an aluminum (111) crystal plane in X-ray diffraction measurement of 2.0° or more and 15.0° or less. [8] The laminate according to [7] above, wherein the aluminum vapor deposition layer is in contact with a resin layer containing an ionomer or a polyvinyl alcohol-based resin having a saponification degree of 95% or more. [9] A packaging bag comprising the laminate according to any one of [1] to [8] above.

[10] The packaging bag described in [9] above, having a folded portion. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide a laminate using paper that has sufficient oil resistance not only after initial oil resistance but also after folding, and a packaging bag including the laminate. Since the laminate uses paper, it has the fold retention characteristic of paper and contributes to reducing the amount of plastic material used. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a laminate according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a perspective view showing a packaging bag according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings where necessary. However, the present disclosure is not limited to the following embodiments.

[0012] <Laminate> The laminate according to the present embodiment is a laminate having a structure in which at least a paper base material, an anchor coat layer, an aluminum vapor deposition layer, and an overcoat layer are laminated in this order, and the aluminum vapor deposition layer is a laminate having a half-width of the peak of the (111) crystal plane of aluminum in X-ray diffraction measurement of 1.6° or more. Here, the half-width in X-ray diffraction of the aluminum vapor deposition layer represents the degree of lattice distortion of the aluminum crystal structure. If the distortion is large, the half-width becomes large, and if the distortion is small, the half-width becomes small. Also, the smaller the distortion, the denser the aluminum crystal structure is. In the laminate, the half-width of the aluminum vapor deposition layer is 1.6° or more, so that the denseness of the aluminum crystal structure can be appropriately reduced to a sparse state. As a result, the stress applied to the aluminum vapor deposition layer when the laminate is folded is distributed throughout the layer, and it is possible to suppress the occurrence of cracks in the aluminum vapor deposition layer when folded and to reduce the occurrence of cracks in the aluminum vapor deposition layer. Therefore, according to the laminate, not only the initial oil resistance but also sufficient oil resistance can be obtained even after folding. Moreover, according to the laminate, by setting the half-width of the aluminum vapor deposition layer within the above range, not only the initial water vapor barrier property but also sufficient water vapor barrier property can be obtained even after folding. Furthermore, according to the laminate, when a material having oxygen barrier property is used for the anchor coat layer, by setting the half-width of the aluminum vapor deposition layer within the above range, not only the initial oxygen barrier property but also sufficient oxygen barrier property can be obtained even after folding. The laminate according to this embodiment is useful as an oil-resistant laminate or a gas barrier laminate.

[0013] In addition, there is room for improvement in the conventional gas barrier laminate, in that the water vapor barrier property deteriorates when stored under high temperature and high humidity (40°C 90% environment). When a gas barrier laminate with deteriorated water vapor barrier property was observed under a microscope with transmitted light, many small bright spots were confirmed, and it is considered that the water vapor barrier property deteriorated due to the occurrence of transmission defects in the aluminum deposition layer. In contrast, the laminate according to the present embodiment includes an aluminum deposition layer in which the half-width of the peak of the aluminum (111) crystal plane in X-ray diffraction measurement is 1.6° or more, and therefore the occurrence of transmission defects in the aluminum deposition layer can be suppressed even when stored under high temperature and high humidity, and the deterioration of the water vapor barrier property can be suppressed. The present inventors speculate as follows about the reason why such an effect is obtained.

[0014] The generation of transmission defects in the aluminum vapor deposition layer is caused by pitting of aluminum caused by corrosive ions and expansion and contraction stress caused by dimensional changes accompanying moisture absorption and desorption of the paper substrate. From the viewpoint of the crystallinity of the aluminum vapor deposition layer, it can be said that the higher the crystallinity, the better it is in terms of resistance to corrosive ions, but in terms of stress resistance, it is considered that amorphous materials, which are more likely to follow expansion and contraction, are superior. Here, it is considered that the aluminum vapor deposition layer has a structure in which the amorphous part is filled around the crystallites. In addition, the broadening of the X-ray diffraction line width of aluminum is due to the diameter of the crystallites and the distortion of the crystals. It is considered that a state in which the X-ray diffraction line width is narrow is a state in which the crystallites and the amorphous part are clearly separated from each other, which are made of an ideal crystal lattice. Therefore, it is presumed that when the X-ray diffraction line width is narrow, pitting in the amorphous part or destruction of the ideal crystal lattice or between the crystal and amorphous due to expansion and contraction stress is likely to occur. On the other hand, it is considered that a state in which the X-ray diffraction line width is wide is a state in which the crystallite has a distorted crystal structure and the separation of the crystal part and the amorphous part is unclear. Therefore, it is presumed that when the X-ray diffraction line width is wide, pitting corrosion and destruction due to expansion and contraction stress are suppressed, and transmission defects are less likely to occur. For the above reasons, it is considered that when the half-width in X-ray diffraction of the aluminum vapor-deposited layer is 1.6° or more, it is possible to suppress the occurrence of transmission defects in the aluminum vapor-deposited layer and suppress deterioration of the water vapor barrier property even when the laminate is stored under high temperature and high humidity conditions. This effect is more remarkable when the half-width is 2.0° or more.

[0015] 1 is a schematic cross-sectional view showing a laminate according to one embodiment. The laminate 10 according to one embodiment includes a paper substrate 1, an anchor coat layer 2, an aluminum vapor deposition layer 3, and an overcoat layer 4, in this order.

[0016] The thickness of the laminate 10 may be 20 to 100 μm, 30 to 80 μm, or 40 to 60 μm. When the thickness of the laminate 10 is within the above range, the laminate 10 can have better water vapor barrier properties and oil resistance not only initially but also after being folded.

[0017] [Paper base material] The paper base material 1 may be paper whose main component is plant-derived pulp. Specific examples of the paper base material 1 include fine paper, special fine paper, coated paper, art paper, cast-coated paper, imitation paper, kraft paper, and glassine paper. The basis weight of the paper base material 1 is 20 to 500 g / m 2 , or 30 to 100 g / m 2 It may be.

[0018] The paper base material 1 may have a coating layer on at least the side of the paper base material 1 that contacts the anchor coat layer 2. When the paper base material 1 has a coating layer, the paper base material 1 may have at least a paper layer and a coating layer. The coating layer may be provided on both surfaces of the paper base material 1. By providing the coating layer, it is possible to prevent the anchor coat layer 2 from penetrating into the paper, and it is also possible to fill the unevenness of the paper, and the anchor coat layer 2 can be formed uniformly without defects. For example, the coating layer may use various copolymers such as styrene-butadiene, styrene-acrylic, and ethylene-vinyl acetate, polyvinyl alcohol resin, cellulose resin, paraffin (WAX), etc. as a binder resin, and may contain clay, kaolin, calcium carbonate, talc, mica, etc. as a filler. The coating layer may be a clay coating layer that contains at least clay as a filler.

[0019] When the paper substrate 1 has a coating layer, the thickness of the coating layer may be 1.5 μm or more and 15 μm or less. The thickness of the coating layer may be 1.8 μm or more, 3 μm or more, 5 μm or more, or 6 μm or more. The thickness of the coating layer may be 12 μm or less, or 10 μm or less. When the thickness of the coating layer is within the above range, the laminate 10 can obtain better water vapor barrier properties and oil resistance not only initially but also after being folded.

[0020] The thickness of the paper base material 1 may be 20 to 100 μm, 30 to 80 μm, or 40 to 60 μm. When the thickness of the paper base material 1 is within the above range, the laminate 10 can have better water vapor barrier properties and oil resistance not only initially but also after being folded.

[0021] The ratio of the thickness of the coating layer to the thickness of the paper base material 1 may be 3 to 25%, or 5 to 20%. When this ratio is within the above range, the laminate 10 can obtain better water vapor barrier properties and oil resistance not only initially but also after being folded.

[0022] The weight of the paper is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, based on the weight of the entire laminate. If the weight of the paper is 50% by mass or more based on the weight of the entire laminate, the amount of plastic material used can be sufficiently reduced, the entire laminate can be said to be made of paper, and the recyclability is excellent.

[0023] [Anchor coat layer] The anchor coat layer 2 is provided on the surface of the paper base material 1 to improve adhesion between the paper base material 1 and the aluminum vapor deposition layer 3 described below, and to improve the gas barrier properties and oil resistance of the laminate. The anchor coat layer 2 may contain a polyolefin or polyvinyl alcohol resin having a polar group.

[0024] When the anchor coat layer 2 contains a polyolefin having a polar group, the anchor coat layer 2 has excellent flexibility, and can suppress cracking of the aluminum vapor-deposited layer 3 described below after bending (folding), and can improve adhesion between the anchor coat layer 2 and the aluminum vapor-deposited layer 3. Furthermore, by containing a polyolefin having a polar group, a dense film can be formed due to the crystallinity of the polyolefin, and water vapor barrier property and oil resistance are exhibited. The crystallinity of the polyolefin exhibits water vapor barrier property and oil resistance, and the presence of a polar group exhibits adhesion with the aluminum vapor-deposited layer 3.

[0025] The polyolefin having a polar group may have at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic anhydride group, and a carboxylic ester.

[0026] As the polyolefin having a polar group, a copolymer of ethylene or propylene with an unsaturated carboxylic acid (an unsaturated compound having a carboxyl group, such as acrylic acid, methacrylic acid, or maleic anhydride), an unsaturated carboxylic acid ester, or a salt obtained by neutralizing a carboxylic acid with a basic compound may be used. In addition, a copolymer of vinyl acetate, an epoxy compound, a chlorine compound, a urethane compound, a polyamide compound, or the like may also be used.

[0027] Specific examples of polyolefins having a polar group include copolymers of acrylic acid ester and maleic anhydride, ethylene-vinyl acetate copolymers, and ethylene-glycidyl methacrylate copolymers.

[0028] On the other hand, when the anchor coat layer 2 contains a polyvinyl alcohol-based resin, the polyvinyl alcohol-based resin has a polar group (hydroxyl group), which easily bonds with metals such as aluminum in the aluminum vapor-deposited layer 3, making it easier to improve the adhesion between the aluminum vapor-deposited layer 3 and the anchor coat layer 2. In addition, such an anchor coat layer 2 has excellent flexibility and can suppress cracking of the aluminum vapor-deposited layer 3 after bending (folding). In addition, the anchor coat layer 2 contains a polyvinyl alcohol-based resin, making it possible to improve the oxygen barrier property of the laminate.

[0029] The polyvinyl alcohol resin is a resin containing vinyl alcohol as a constituent unit, and examples of the polyvinyl alcohol resin include fully saponified polyvinyl alcohol resin, partially saponified polyvinyl alcohol resin, modified polyvinyl alcohol resin, and ethylene-vinyl alcohol copolymer resin. From the viewpoint of oxygen barrier properties, the saponification degree of the polyvinyl alcohol resin is preferably high, and may be 95% or more, or may be 98% or more.

[0030] The anchor coat layer 2 may contain both a polyolefin having a polar group and a polyvinyl alcohol-based resin.

[0031] The anchor coat layer 2 may contain other components in addition to the above-mentioned polyolefin having a polar group and polyvinyl alcohol resin. Examples of the other components include polyolefins other than the above-mentioned polyolefin having a polar group, silane coupling agents, organic titanates, polyacrylics, polyesters, polyurethanes, polycarbonates, polyureas, polyamides, polyimides, melamines, phenols, and the like.

[0032] The content of the polyolefin or polyvinyl alcohol resin having the polar group in the anchor coat layer 2 may be, for example, 50 mass % or more, 70 mass % or more, 90 mass % or more, or 100 mass %.

[0033] The thickness of the anchor coat layer 2 may be, for example, 0.5 μm or more, 1 μm or more, 2 μm or more, 20 μm or less, 10 μm or less, or 5 μm or less. If the thickness of the anchor coat layer 2 is 0.5 μm or more, the unevenness of the paper base material described above can be efficiently filled, and the aluminum vapor deposition layer described later can be laminated uniformly. Also, if the thickness of the anchor coat layer 2 is 20 μm or less, the aluminum vapor deposition layer can be laminated uniformly while suppressing costs.

[0034] The anchor coat layer 2 may have a hardness of 0.3 GPa or less as measured by a nanoindentation method in a cross section in the thickness direction of the laminate 10. Such an anchor coat layer 2 has excellent flexibility and can suppress cracking of the aluminum vapor-deposited layer 3 described below after bending (folding), and can improve adhesion between the anchor coat layer 2 and the aluminum vapor-deposited layer 3.

[0035] Examples of the solvent contained in the coating liquid of the anchor coat layer 2 include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, toluene, hexane, heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate, and butyl acetate. These solvents may be used alone or in combination of two or more. Among these, from the viewpoint of characteristics, methyl alcohol, ethyl alcohol, isopropyl alcohol, toluene, ethyl acetate, methyl ethyl ketone, and water are preferred. Furthermore, from the viewpoint of the environment, methyl alcohol, ethyl alcohol, isopropyl alcohol, and water are preferred.

[0036] The anchor coat layer 2 can be provided by applying a coating liquid containing the above-mentioned polyolefin or polyvinyl alcohol resin having a polar group, a solvent, and the like onto the paper substrate, and then drying the coating liquid.

[0037] [Aluminum vapor deposition layer] The aluminum vapor deposition layer 3 is a layer formed by vapor deposition of aluminum or an aluminum compound. The aluminum vapor deposition layer may be one obtained by vapor deposition of aluminum, or may be one obtained by vapor deposition of aluminum oxide (AlO x ), silicon oxide (SiO x ) etc.

[0038] The thickness of the aluminum vapor deposition layer 3 may be appropriately set depending on the intended use, but is preferably 10 to 300 nm, more preferably 20 to 100 nm, and even more preferably 30 to 100 nm. By setting the thickness of the aluminum vapor deposition layer 3 to 10 nm or more, the continuity of the aluminum vapor deposition layer 3 is easily ensured, and by setting the thickness to 300 nm or less, the occurrence of curling and cracking can be sufficiently suppressed, and sufficient gas barrier performance, oil resistance, and flexibility can be easily achieved. Furthermore, by setting the thickness of the aluminum vapor deposition layer to 20 nm or more and 100 nm or less, the aluminum vapor deposition layer becomes less likely to crack, and sufficient water vapor barrier property and oil resistance can be obtained even after bending. From the viewpoint of further suppressing the deterioration of the water vapor barrier property of the laminate 10 when stored under high temperature and high humidity conditions, the thickness of the aluminum vapor deposition layer 3 may be 50 to 300 nm, 60 to 150 nm, or 60 to 100 nm.

[0039] The aluminum vapor deposition layer 3 is preferably formed by a vacuum deposition method from the viewpoints of water vapor and oxygen gas barrier performance, oil resistance, and film uniformity. There are known methods for forming the film, such as vacuum deposition, sputtering, and chemical vapor deposition (CVD), but vacuum deposition is preferred because of its fast film formation speed and high productivity. Among the vacuum deposition methods, deposition by electron beam heating is particularly effective because the film formation speed can be easily controlled by the irradiation area and electron beam current, and the temperature of the deposition material can be raised and lowered in a short time.

[0040] The aluminum vapor deposition layer 3 is a layer in which the half-width of the peak of the (111) crystal plane of aluminum in X-ray diffraction measurement is 1.6° or more. The half-width may be 1.8° or more, 2.0° or more, or 2.1° or more. When the half-width is 1.6° or more, it is possible to suppress the occurrence of cracks in the aluminum vapor deposition layer 3 when the laminate 10 is folded, and it is possible to suppress the deterioration of the gas barrier property and oil resistance after folding. This effect is more remarkable when the half-width is 2.0° or more. Furthermore, when the half-width is 1.6° or more, it is possible to suppress the occurrence of transmission defects in the aluminum vapor deposition layer 3 even when the laminate 10 is stored under high temperature and high humidity conditions (for example, under a 40°C and 90% humidity environment), and it is possible to suppress the deterioration of the water vapor barrier property of the laminate 10. This effect is also more remarkable when the half-width is 2.0° or more. The upper limit of the half-width may be, for example, 15.0° or less, or 10.0° or less, from the viewpoint of the denseness of the aluminum crystal structure. If the resin layer in contact with the aluminum vapor-deposited layer contains an ionomer or a polyvinyl alcohol-based resin with a saponification degree of 95% or more, the aluminum vapor-deposited layer is easily corroded. If the crystallinity of the aluminum vapor-deposited layer is low, such problems are likely to occur. If the half-width is 15.0° or less, even if the resin layer in contact with the aluminum vapor-deposited layer contains an ionomer or a polyvinyl alcohol-based resin with a high saponification degree, the aluminum vapor-deposited layer is unlikely to corrode. This effect is also more pronounced when the half-width is 10.0° or less. In order to achieve both of the above effects, the half-width is preferably 1.6° or more and 15.0° or less, 1.6° or more and 10.0° or less, 1.6° or more and 7.0° or less, 1.6° or more and 5.0° or less, 2.0° or more and 15.0° or less, 2.0° or more and 10.0° or less, 2.0° or more and 7.0° or less, or 2.0° or more and 5.0° or less.

[0041] The half-width (2θ) of the peak of the (111) crystal plane of aluminum in the aluminum deposition layer 3 is measured using an X-ray diffractometer. For example, an ATX-G (product name) manufactured by Rigaku Electric Corporation can be used as the X-ray diffractometer. The measurement can be performed from above the overcoat layer 4 by fixing the laminate as a sample on a slide glass. As the X-ray diffraction of aluminum, the half-width of the peak at 2θ=38.5° corresponding to the (111) plane (d=2.34) is measured. The measurement conditions are as follows: Light source: CuKα line Tube voltage: 50kV Tube current: 300mA Optical system: Parallel beam optical system Scan method: 2θ / θ method Measurement range: 30°~50° Sampling step: 0.02° Scan speed: 2° / min slit S1: 10.0mm x 1.0mm S2: 10.0mm x 0.5mm Sollar(res):0.4mm

[0042] The half-width can be controlled by adjusting the conditions during the formation of the aluminum vapor-deposited layer 3. For example, the half-width can be controlled by adjusting the pressure in the deposition chamber during the formation of the aluminum vapor-deposited layer 3. Here, the half-width can be increased by increasing the pressure in the deposition chamber, and the half-width can be decreased by decreasing the pressure in the deposition chamber. The pressure in the deposition chamber during the formation of the aluminum vapor-deposited layer 3 may be 0.05 Pa or more, 0.10 Pa or more, or 0.20 Pa or more, since it is easy to adjust the half-width to 1.6° or more. The upper limit of the pressure is not particularly limited as long as it is within a range in which the aluminum vapor-deposited layer 3 can be formed, and may be, for example, 0.50 Pa or less, or 0.40 Pa or less.

[0043] [Overcoat layer] The overcoat layer 4 is provided on the surface of the aluminum vapor-deposited layer 3 so as to be in contact with the aluminum vapor-deposited layer 3. The overcoat layer may contain a polyolefin having a polar group.

[0044] The polyolefin having a polar group may have at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic anhydride group, and a carboxylic ester.

[0045] As the polyolefin having a polar group, a copolymer of ethylene or propylene with an unsaturated carboxylic acid (an unsaturated compound having a carboxyl group, such as acrylic acid or methacrylic acid) or an unsaturated carboxylic acid ester, or a salt obtained by neutralizing a carboxylic acid with a basic compound may be used. In addition, a copolymer of vinyl acetate, an epoxy compound, a chlorine compound, a urethane compound, a polyamide compound, or the like may also be used.

[0046] Specific examples of polyolefins having a polar group include copolymers of acrylic acid ester and maleic anhydride, ethylene-vinyl acetate copolymers, and ethylene-glycidyl methacrylate copolymers.

[0047] By including a polyolefin having a polar group, the overcoat layer 4 has excellent flexibility, can suppress cracking of the aluminum vapor deposition layer after bending (folding), and has excellent adhesion to the aluminum vapor deposition layer. Furthermore, by including the polyolefin having the above-mentioned polar group, a dense film can be formed due to the crystallinity of the polyolefin, and water vapor barrier properties and oil resistance are exhibited. Furthermore, by including the polar group, adhesion to the aluminum vapor deposition layer is exhibited. Furthermore, by including the polyolefin having the above-mentioned polar group, the overcoat layer 4 can also serve as a heat seal layer, so there is no need to provide a separate heat seal layer.

[0048] The overcoat layer 4 may contain other components in addition to the polyolefin having a polar group, such as a silane coupling agent, an organic titanate, polyacrylic, polyester, polyurethane, polycarbonate, polyurea, polyamide, a polyolefin emulsion, polyimide, melamine, and phenol.

[0049] The content of the polyolefin having a polar group in the overcoat layer 4 may be, for example, 50% by mass or more, 70% by mass or more, 90% by mass or more, or 100% by mass.

[0050] The thickness of the overcoat layer 4 may be, for example, 0.05 μm or more, 0.5 μm or more, 1 μm or more, 2 μm or more, 20 μm or less, 10 μm or less, or 5 μm or less. If the thickness of the overcoat layer 4 is 0.05 μm or more, the above-mentioned role as a heat seal layer can be fully exerted. Furthermore, if the thickness of the overcoat layer 4 is 20 μm or less, the adhesion and barrier properties with the aluminum deposition layer can be fully exerted while suppressing costs. Furthermore, by setting the thickness of the overcoat layer 4 to 2 μm or more and 10 μm or less, the aluminum deposition layer becomes less likely to crack, and sufficient water vapor barrier properties and oil resistance can be obtained even after bending.

[0051] In the laminate 10, when the overcoat layer 4 contains a polyolefin having a polar group, the thickness of the overcoat layer 4 is set to 2 μm or more and 10 μm or less, and the thickness of the aluminum vapor-deposited layer 3 is set to 20 nm or more and 100 nm or less, the aluminum vapor-deposited layer 3 is less likely to crack, and the effect of obtaining sufficient water vapor barrier properties and oil resistance even after bending is particularly remarkable.

[0052] The overcoat layer 4 may have a hardness of 0.3 GPa or less as measured by a nanoindentation method in a cross section in the thickness direction of the laminate 10. Such an overcoat layer 4 has excellent flexibility, can suppress cracking of the aluminum vapor-deposited layer 3 after bending (folding), and can suppress deterioration of the gas barrier property and oil resistance.

[0053] Examples of the solvent contained in the coating liquid for the overcoat layer 4 include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, toluene, hexane, heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate, and butyl acetate. These solvents may be used alone or in combination of two or more. Among these, from the viewpoint of characteristics, methyl alcohol, ethyl alcohol, isopropyl alcohol, toluene, ethyl acetate, methyl ethyl ketone, and water are preferred. Furthermore, from the viewpoint of the environment, methyl alcohol, ethyl alcohol, isopropyl alcohol, and water are preferred.

[0054] The overcoat layer 4 can be provided by applying a coating liquid containing the above-mentioned polyolefin having a polar group and a solvent on the aluminum deposition layer and drying it. The melting point of the polyolefin having a polar group in the coating liquid is preferably 70 to 160°C, more preferably 80 to 120°C. If the melting point of the polyolefin having a polar group is low, there is an advantage in that the start-up temperature during heat sealing can be lowered. If the melting point of the polyolefin having a polar group is low, there is an increased risk of blocking in a high-temperature environment. In addition, from the viewpoint of preventing blocking, it is better to have a large particle size so that the contact area is small. Although not particularly limited, the particle size may be specifically 1 nm or more, 0.1 μm or more, 1 μm or less, 0.7 μm or less, or 0.5 μm or less.

[0055] (Method of processing cross-section of measurement sample using nanoindentation method) In the measurement by the nanoindentation method, the anchor coat layer 2 and the overcoat layer 4 are measured from the cross section of the laminate 10. The laminate sample including the anchor coat layer 2 and the overcoat layer 4 is cut into a rectangular or wedge shape with a razor and embedded in resin. A photocurable resin (for example, D-800 manufactured by Toa Gosei Co., Ltd.) is used as the embedding resin, and the sample is hardened by light irradiation after embedding. The hardened sample embedding resin is fixed with an insert for an AFM sample holder, and trimming and cross-cutting of the laminate are performed with a glass knife at room temperature (25°C), and cross-cutting is performed with a diamond knife at a cutting speed of 1.0 mm / s and a cutting film thickness of 200 nm until a mirror surface is obtained. The sample with the cross section exposed is used for measurement by the nanoindentation method while being fixed with an insert for an AFM sample holder. For example, an ultramicrotome EMUC7 manufactured by Leica can be used as the cross-section cutting device. The cutting direction is parallel to the layer interface.

[0056] (Measuring method using nanoindentation method) The hardness and composite modulus of the anchor coat layer and the overcoat layer are calculated by the nanoindentation method. The nanoindentation method is a measurement method in which a quasi-static indentation test is performed on a target measurement object to obtain the mechanical properties of the sample. For example, a Hysitron TI-Premier (product name) manufactured by Bruker Japan Co., Ltd. can be used as the measurement device. For the indenter, a Berkovich type diamond indenter manufactured by Bruker Japan Co., Ltd. can be used. In the measurement by the nanoindentation method, first, the diamond indenter is used to scan the cross section of the sample to obtain a shape image of the sample, and the measurement position of the desired layer is specified. Then, in a displacement control mode at room temperature (25°C), the indenter is indented to a depth of 80 nm at a indentation speed of 80 nm / sec, and then the maximum depth is held for 1 second, and then the load is removed at a speed of 80 nm / sec. The method of calculating the hardness and composite modulus is to test fused quartz as a standard sample in advance, and calibrate the relationship between the contact depth and the contact projection area of ​​the indenter and the sample. Then, the unloading curve in the region of 60 to 95% of the maximum load at the time of unloading is analyzed by the Oliver-Pharr method, and the hardness and composite elastic modulus are calculated.

[0057] The hardness of the anchor coat layer 2 and the overcoat layer 4 measured by the nanoindentation method in the cross section in the thickness direction of the laminate 10 may be 0.3 GPa or less. This reduces the direct transmission of the deformation stress of the paper base material caused by bending the laminate to the aluminum vapor deposition layer, thereby preventing defects from occurring in the aluminum vapor deposition layer, thereby suppressing deterioration of the gas barrier property and oil resistance after bending. From this viewpoint, the hardness of the anchor coat layer 2 and the overcoat layer 4 may be 0.25 GPa or less, or may be 0.2 GPa or less. The lower limit of the hardness is not particularly limited, but from the viewpoint of obtaining sufficient strength to maintain the gas barrier property and oil resistance, it can be 0.05 MPa or more.

[0058] In order to form a flexible anchor coat layer 2 and overcoat layer 4 having a hardness of 0.3 GPa or less as measured by nanoindentation in a cross section in the thickness direction of the laminate 10, it is preferable to form the anchor coat layer 2 and overcoat layer 4 using a resin material whose dried film has an elongation at break of preferably 150% or more, more preferably 200% or more, as measured in an atmosphere of 20°C and 65% RH in accordance with JIS K7161.

[0059] <Packaging bag> 2 is a perspective view showing a gusset bag 20 made of the laminate 10. A packaging bag is manufactured by sealing the opening at the top of the gusset bag 20. The gusset bag 20 has portions where the laminate 10 is folded (folded portions B1, B2). The folded portion B1 is a portion where the laminate 10 is folded in a valley direction when viewed from the innermost layer side, while the folded portion B2 is a portion where the laminate 10 is folded in a mountain direction when viewed from the innermost layer side.

[0060] The packaging bag may be formed into a bag shape by folding one laminate in half so that the overcoat layers 4 face each other, then folding appropriately into the desired shape and heat sealing, or may be formed into a bag shape by stacking two laminates so that the overcoat layers 4 face each other, and then heat sealing.

[0061] In the packaging bag according to the present embodiment, the heat seal strength may be 2 N or more, or 4 N or more. The upper limit of the heat seal strength is not particularly limited, but may be, for example, 10 N or less.

[0062] The packaging bag can contain food, medicine, and the like. It is particularly suitable for containing food, such as sweets. The packaging bag according to the present embodiment can maintain high gas barrier properties and oil resistance even in a shape having a folded portion.

[0063] In this embodiment, a gusset bag is given as an example of a packaging bag, but the laminate according to this embodiment may be used to produce, for example, a pillow bag, a three-side sealed bag, or a standing pouch. EXAMPLES

[0064] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to these examples.

[0065] <Preparation of Laminate> Example 1 An aqueous dispersion of a polyolefin containing a salt of a carboxyl group (manufactured by Sumitomo Seika Chemicals Co., Ltd., product name: ZAIKXEN AC, particle size: less than 0.2 μm, solvent: water / IPA = 1 / 1 (mass ratio), solids concentration: 22.5 mass%) was applied with a bar coater onto the surface of the clay coat layer side of a paper substrate (thickness including the clay coat layer: 55 μm) having a 5 μm thick clay coat layer, and then dried in an oven to form an anchor coat layer with a thickness of 3 μm.

[0066] Subsequently, Al was deposited on the anchor coat layer by vacuum deposition to form an Al deposited layer (aluminum deposited layer) having a thickness of 50 nm. The pressure in the deposition chamber during deposition of aluminum was adjusted to the value shown in Table 1.

[0067] Next, an aqueous dispersion of polyolefin containing a salt of a carboxyl group (manufactured by Mitsui Chemicals, Inc., product name: Chemipearl S100, particle size: less than 0.1 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content: 20.0 mass%) was applied onto the Al vapor deposition layer using a bar coater and dried in an oven to form an overcoat layer with a thickness of 3 μm. This produced a laminate.

[0068] Example 2 A laminate was obtained in the same manner as in Example 1, except that the pressure in the deposition chamber when forming the Al deposited layer was changed to the value shown in Table 1.

[0069] Example 3 A laminate was obtained in the same manner as in Example 1, except that the paper substrate was changed to a paper substrate having a clay coating layer with a thickness of 5 μm (thickness including the clay coating layer: 50 μm).

[0070] Example 4 A laminate was obtained in the same manner as in Example 1, except that the anchor coat layer was formed by the following method: That is, on the surface of the clay coat layer side of a paper substrate (thickness including the clay coat layer: 55 μm), an aqueous dispersion of a polyolefin containing a carboxyl group salt (manufactured by Mitsui Chemicals, Inc., product name: Chemipearl S100, particle size: less than 0.1 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content concentration: 20.0 mass%) was applied with a bar coater, and dried in an oven to form an anchor coat layer with a thickness of 3 μm.

[0071] Example 5 A laminate was obtained in the same manner as in Example 1, except that the overcoat layer was formed by the following method: An aqueous dispersion of polyolefin containing a salt of a carboxyl group (manufactured by Mitsui Chemicals, Inc., product name: Chemipearl S500, particle size: 0.7 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content concentration: 20.0 mass%) was applied onto the Al vapor deposition layer using a bar coater, and then dried in an oven to form an overcoat layer having a thickness of 3 μm.

[0072] (Examples 6 to 7) A laminate was obtained in the same manner as in Example 1, except that the pressure in the deposition chamber when forming the Al vapor-deposited layer was changed to the value shown in Table 1, and the thickness of the Al vapor-deposited layer was changed to the value shown in Table 1.

[0073] Example 8 A laminate was obtained in the same manner as in Example 1, except that the anchor coat layer was formed by the following method: That is, a solution of polyvinyl alcohol (PVA) resin with a saponification degree of 98% and a polymerization degree of 500 dissolved in a solvent of water / IPA = 8 / 2 (mass ratio) at a solid content concentration of 10 mass % was applied to the surface of the clay coat layer side of the paper substrate (thickness including the clay coat layer: 55 μm) with a bar coater, and dried in an oven to form an anchor coat layer with a thickness of 3 μm.

[0074] Example 9 A laminate was obtained in the same manner as in Example 8, except that the pressure in the deposition chamber when forming the Al deposited layer was changed to the value shown in Table 2.

[0075] (Comparative Examples 1 to 2) A laminate was obtained in the same manner as in Example 1, except that the pressure in the deposition chamber when forming the Al deposited layer was changed to the value shown in Table 2.

[0076] Comparative Example 3 A laminate was obtained in the same manner as in Example 8, except that the pressure in the deposition chamber when forming the Al deposited layer was changed to the value shown in Table 2.

[0077] <Preparation of paper substrate> As paper substrates, the following clay-coated papers 1 to 3 and uncoated paper 4 were prepared. Clay-coated paper 1: When the temperature was changed from 40°C and 20% relative humidity to 40°C and 90% relative humidity, the dimensional change was CD = 0.75%, MD = 0.13%, and the basis weight was 60g / m 2 Clay-coated paper 2: When the temperature was changed from 40°C and 20% relative humidity to 40°C and 90% relative humidity, the dimensional change was CD = 0.55%, MD = 0.07%, and the basis weight was 60g / m 2 Clay-coated paper 3: When the temperature was changed from 40°C and 20% relative humidity to 40°C and 90% relative humidity, the dimensional change was CD = 0.35%, MD = 0.15%, and the basis weight was 60g / m 2 Uncoated paper 4: When the temperature was changed from 40°C and 20% relative humidity to 40°C and 90% relative humidity, the dimensional change was CD = 1.34%, MD = 0.03%, and the basis weight was 62g / m 2

[0078] <Preparation of Laminate> Example 10 Clay-coated paper 1 was prepared as the paper substrate. An aqueous dispersion of polyolefin containing a salt of a carboxyl group (manufactured by Sumitomo Seika Chemicals Co., Ltd., product name: ZAIKXEN AC, particle size: less than 0.2 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content concentration: 22.5 mass%) was applied onto the surface of the clay-coat layer side of the paper substrate using a gravure coater, and then dried in an oven to form an anchor coat layer with a thickness of 3 μm.

[0079] Next, an Al vapor deposition layer was formed on the anchor coat layer using a roll-to-roll induction heating vacuum deposition device. The pressure in the deposition chamber during Al vapor deposition and the thickness of the Al vapor deposition layer were adjusted to the values ​​shown in Table 3.

[0080] Next, an aqueous dispersion of polyolefin containing a salt of a carboxyl group (manufactured by Mitsui Chemicals, Inc., product name: Chemipearl S100, particle size: less than 0.1 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content: 20.0 mass%) was applied onto the Al vapor deposition layer using a gravure coater and dried in an oven to form an overcoat layer with a thickness of 3 μm. This produced a laminate.

[0081] Example 11 A laminate was obtained in the same manner as in Example 10, except that the paper substrate was changed to clay-coated paper 2, and the pressure in the deposition chamber when forming the Al vapor-deposited layer and the thickness of the Al vapor-deposited layer were changed to the values ​​shown in Table 3.

[0082] Example 12 A laminate was obtained in the same manner as in Example 10, except that the Al vapor-deposited layer was formed by the following method. That is, the Al vapor-deposited layer was formed on the anchor coat layer by a roll-to-roll EB heating type vacuum vapor deposition apparatus. The pressure in the vapor deposition chamber during Al vapor deposition and the thickness of the Al vapor-deposited layer were adjusted to the values ​​shown in Table 3.

[0083] (Example 13) A laminate was obtained in the same manner as in Example 12, except that the paper substrate was changed to clay-coated paper 2.

[0084] Example 14 A laminate was obtained in the same manner as in Example 12, except that the paper substrate was changed to clay-coated paper 3.

[0085] Example 15 Clay-coated paper 2 was prepared as the paper substrate. A solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: Poval 5-98) with a saponification degree of 98% and a polymerization degree of 500 dissolved in a solvent of water / IPA = 8 / 2 (mass ratio) at a solid content concentration of 10 mass % was applied on the surface of the paper substrate on the clay coating layer side with a gravure coater, and dried in an oven to form an anchor coat layer with a thickness of 4 μm.

[0086] Next, an Al vapor deposition layer was formed on the anchor coat layer using a roll-to-roll EB heating vacuum deposition device. The pressure in the deposition chamber during Al vapor deposition and the thickness of the Al vapor deposition layer were adjusted to the values ​​shown in Table 3.

[0087] Next, an aqueous dispersion of polyolefin containing a salt of a carboxyl group (manufactured by Mitsui Chemicals, Inc., product name: Chemipearl S500, particle size: 0.7 μm, solvent: water / IPA=1 / 1 (mass ratio), solid content: 20.0 mass%) was applied onto the Al vapor deposition layer using a gravure coater and dried in an oven to form an overcoat layer with a thickness of 3 μm. This produced a laminate.

[0088] Example 16 A laminate was obtained in the same manner as in Example 15, except that the paper substrate was changed to clay-coated paper 1, and the pressure in the deposition chamber when forming the Al vapor-deposited layer and the thickness of the Al vapor-deposited layer were changed to the values ​​shown in Table 3.

[0089] (Example 17) As the paper substrate, uncoated paper 4 was prepared. A solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., product name: Poval 5-98) with a saponification degree of 98% and a polymerization degree of 500 dissolved in a solvent of water / IPA = 8 / 2 (mass ratio) at a solid content concentration of 10 mass % was applied on one surface of the paper substrate using a gravure coater, and dried in an oven to form an anchor coat layer with a thickness of 3 μm.

[0090] Subsequently, an Al vapor deposition layer was formed on the anchor coat layer using a roll-to-roll EB heating type vacuum deposition apparatus. The pressure in the deposition chamber during Al vapor deposition and the thickness of the Al vapor deposition layer were adjusted to the values shown in Table 4.

[0091] Next, an aqueous dispersion of ethylene-acrylic acid copolymer resin (manufactured by MICHELMAN, trade name: MC9100, solid content concentration: 20% by mass) was coated on the Al vapor deposition layer using a gravure coater and dried in an oven to form an overcoat layer with a thickness of 3 μm. Thereby, a laminate was obtained.

[0092] (Comparative Examples 4 to 6) A laminate was obtained in the same manner as in Example 10, except that the pressure in the deposition chamber during formation of the Al vapor deposition layer and the thickness of the Al vapor deposition layer were changed to the values shown in Table 4.

[0093] (Comparative Example 7) A laminate was obtained in the same manner as in Example 12, except that the pressure in the deposition chamber during formation of the Al vapor deposition layer and the thickness of the Al vapor deposition layer were changed to the values shown in Table 4.

[0094] (Comparative Example 8) A laminate was obtained in the same manner as in Example 15, except that the pressure in the deposition chamber during formation of the Al vapor deposition layer and the thickness of the Al vapor deposition layer were changed to the values shown in Table 4.

[0095] <Measurement of the film thickness of the Al vapor deposition layer> The laminate was embedded in a UV-curing resin and cut cross-sectionally using a cryomicrotome to prepare a cross-sectional observation sample. The cross-section of this sample was observed with an electron microscope at a magnification of 50,000 times to obtain an SEM image. The thickness of the Al vapor deposition layer was measured from the obtained SEM image. The results are shown in Tables 1 to 4.

[0096] <X-ray diffraction measurement> The half-width of the peak of the (111) crystal plane of aluminum in the Al deposition layer was measured by the following procedure. For the measurement of the half-width, an X-ray diffractometer (product name: ATX-G) manufactured by Rigaku Electric Co., Ltd. was used. CuKα rays were used as the light source, the tube voltage was 50 kV, the tube current was 300 mA, the optical system was a parallel beam optical system, the scanning method was the 2θ / θ method, the measurement range was 30° to 50°, and the scanning speed was 2° / min. The sampling step was 0.02°, and the slits were S1: 10.0 mm x 1.0 mm, S2: 10.0 mm x 0.5 mm, and Sollar (res): 0.4 mm. The laminates obtained in the examples and comparative examples were used as samples, and the paper substrate side was attached to a slide glass with double-sided tape to perform X-ray diffraction measurement. As the X-ray diffraction of aluminum, the half-width of the peak at 2θ = 38.5° corresponding to the (111) plane (d = 2.34) was measured. The results are shown in Tables 1 to 4.

[0097] <Sample cross-section processing method> Samples for measuring the hardness and composite modulus of the anchor coat layer and the overcoat layer from the cross-section of the laminate obtained in the examples and comparative examples were prepared by the following procedure. First, the laminate was cut with a razor so that the sample including the anchor coat layer and the overcoat layer was in a rectangular or wedge shape, and the obtained sample was embedded in resin. D-800 photocurable resin manufactured by Toa Gosei Co., Ltd. was used as the embedding resin, and the sample was hardened by light irradiation after embedding. The hardened sample embedding resin was fixed with an insert for AFM sample holder, trimming and cross-section cutting of the film were performed with a glass knife at room temperature (25°C), and cross-section cutting was performed with a diamond knife at a cutting speed of 1.0 mm / sec and a cutting film thickness of 200 nm until a mirror surface was obtained. The cross-sectioned sample was used for measurement by the nanoindentation method while being fixed with an insert for AFM sample holder. An ultramicrotome EMUC7 manufactured by Leica was used as the cross-section cutting device. The cutting direction was parallel to the layer interface.

[0098] <Measurement of hardness and composite elastic modulus> The hardness and complex elastic modulus of the anchor coat layer and the overcoat layer represent the hardness and complex elastic modulus calculated by the nanoindentation method. The nanoindentation method is a measurement method that performs a quasi-static indentation test on the target measurement object to obtain the mechanical properties of the sample. The measurement device used was the Hysitron TI-Premier (trade name) manufactured by Bruker Japan Co., Ltd. The indenter used was a Berkovich-type diamond indenter manufactured by Bruker Japan Co., Ltd. For the measurement by the nanoindentation method, first, the shape image of the sample was obtained by scanning the sample cross-section with a diamond indenter, and the measurement position of the desired layer was specified. Then, at room temperature (25 °C) in displacement control mode, after indenting to a depth of 80 nm at an indenting speed of 80 nm / second, it was held for 1 second at the maximum depth and then unloaded at a speed of 80 nm / second. For the calculation method of the hardness and complex elastic modulus, fused quartz as a standard sample was pre-tested to calibrate the relationship between the contact depth and the contact projected area of the indenter and the sample. Then, the unloading curve in the 60 - 95% region with respect to the maximum load during unloading was analyzed by the Oliver-Pharr method to calculate the hardness and complex elastic modulus. The results are shown in Tables 1 - 4.

[0099] <Measurement of elongation at break> For the measurement of the elongation at break of the anchor coat layer and the overcoat layer, the coating solution for forming the anchor coat layer and the overcoat layer on the support substrate was applied and dried, then peeled off from the support substrate, punched into a dumbbell shape of type 1A to obtain test pieces, and measured based on the method described in JIS K7161. As the device, an autograph testing machine AGS-X (manufactured by Shimadzu Corporation) was used, the tensile test speed was 50 mm / min, and the measurement was carried out in an environment of temperature 20 °C and humidity 65%. The results are shown in Tables 1 - 4.

[0100] <Measurement of KIT value> The oil resistance (KIT value) of the surface of the overcoat layer side of the laminate obtained in the examples and comparative examples was measured by the TAPPI UM-557 method (Kit method). In addition, while rolling a 1500g roller at a speed of 300mm / min, the laminate was folded parallel to the MD direction so that the laminate was valley-folded when viewed from the paper base material side (so that the overcoat layer was on the outer surface), and the oil resistance (KIT value) of the folded part of the laminate after opening was also measured in the same manner. The KIT value is expressed as grades 0 to 12, and the higher the number, the higher the oil resistance. The highest oil resistance given by the KIT test liquid that does not show penetration was used as the evaluation result. The KIT value is preferably 6 or more, and if it is less than 6, the oil resistance for food packaging may not be satisfied. The results are shown in Tables 1 to 4.

[0101] <Measurement of water vapor permeability> The laminates obtained in the examples and comparative examples were subjected to the water vapor transmission rate (g / m 2 / day) was measured by the MOCON method in accordance with JIS K7129-2. A water vapor transmission rate measuring device (manufactured by MOCON, product name: PERMATRAN-W3 / 34G) was used for the measurement. Furthermore, the laminate was stored in a thermo-hygrostat at 40°C and 90% RH for one week, and then the same measurement was performed. The water vapor transmission rates initially and after storage at 40°C and 90% RH are shown in Tables 1 to 4.

[0102] [Table 1]

[0103] [Table 2]

[0104] [Table 3]

[0105] [Table 4]

[0106] As shown in Tables 1 to 4, the laminates of the examples had good oil resistance (KIT value) not only initially but also after bending. Also, as shown in Tables 1 to 4, the laminates of the examples had a water vapor transmission rate of 6 g / m2 or less even after storage at 40°C and 90% RH for one week. 2 / d or less, and it was confirmed that good water vapor barrier properties could be maintained. [Explanation of symbols]

[0107] Reference Signs List: 1...paper base material, 2...anchor coat layer, 3...aluminum vapor deposition layer, 4...overcoat layer, 10...laminate, 20...gusset bag, B1, B2...folded portion.

Claims

1. A laminate having a structure in which at least a paper base material, an anchor coat layer, and an aluminum vapor deposition layer are laminated in this order, wherein the aluminum vapor deposition layer has a half-value width of a peak of the (111) crystal plane of aluminum in X-ray diffraction measurement of 1.6° or more and 15.0° or less, and the anchor coat layer contains a polyolefin or a polyvinyl alcohol-based resin having a polar group.

2. The laminate according to claim 1, having a heat-sealable layer on the surface of the aluminum vapor deposition layer.

3. The laminate according to claim 1, wherein the hardness of the anchor coat layer measured by nanoindentation method in a cross-section in the thickness direction of the laminate is 0.3 GPa or less.

4. The laminate according to claim 1, wherein the thickness of the aluminum vapor deposition layer is 20 nm or more and 100 nm or less.

5. The laminate according to claim 1, wherein the thickness of the paper base material is 20 μm or more and 100 μm or less.

6. The laminate according to claim 1, wherein the aluminum vapor deposition layer is in contact with a resin layer containing an ionomer or a polyvinyl alcohol-based resin having a saponification degree of 95% or more.

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