Laminate and lid material using same

Abstract

To provide a laminate which is suitably usable for a mono-material packaging container, can remarkably improve interlayer adhesion between a base material and a vapor-deposited film, can achieve suitable gas barrier properties, and has heat resistance.SOLUTION: A laminate has at least a first base material, a vapor-deposited film, and a sealant layer, in which the first base material has a polypropylene resin layer and a surface resin layer provided on one surface of the polypropylene resin layer, the vapor-deposited film is provided on the surface resin layer of the first base material, the first base material is subjected to drawing treatment, the surface resin layer contains a resin material having a melting point of 180°C or higher, the vapor-deposited film is composed of an inorganic oxide, the sealant layer contains polyolefin having a melting point of 110°C or higher, and the sealant layer is an easy peel sealant layer where the polyolefin is polypropylene.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a laminate, and more particularly to a laminate that can be suitably used as a mono-material packaging material, and a lid material using the same. [Background technology]

[0002] Conventionally, films made of polyesters such as polyethylene terephthalate (hereinafter also referred to as polyester films) have been used as substrates for constituting laminates used in the production of packaging containers because they have excellent mechanical properties, chemical stability, heat resistance, and transparency, as well as being inexpensive.

[0003] The polyester film is usually laminated with a sealant layer, which is a polyolefin film such as a polypropylene film, and then molded into a packaging container.

[0004] In the packaging container obtained by molding a laminate of the above-mentioned different resin films, i.e., a polyester film and a polypropylene film, it is difficult to separate the resin films. Therefore, the packaging container collected after use is not suitable for recycling and is not actively recycled at present.

[0005] In light of this current situation, and with the aim of improving the recyclability of packaging containers, studies are being conducted on the production of packaging containers (mono-material packaging containers) using a laminate made of the same material, in which stretched polypropylene film (stretched polypropylene film) is used as the base material instead of polyester film. Summary of the Invention [Problem to be solved by the invention]

[0006] Recently, the present inventors have formed a vapor-deposited film on the surface of a stretched polypropylene film to compensate for the reduced gas barrier property caused by replacing the polyester film with a stretched polypropylene film. However, the adhesion between the stretched polypropylene film and the vapor-deposited film was insufficient, and the desired gas barrier property was not achieved. Therefore, the present inventors have discovered a new problem.

[0007] The inventors have discovered that, rather than forming a vapor-deposited film on the surface of a stretched polypropylene film, by providing a surface resin layer containing a resin material having a melting point of 180°C or higher on the surface of the stretched polypropylene film and then forming a vapor-deposited film on the surface resin layer, adhesion can be improved and gas barrier properties can also be improved.

[0008] Furthermore, the inventors have discovered that, rather than forming a vapor-deposited film on the surface of a stretched polypropylene film, by providing a surface coating layer containing a resin material having a polar group on the surface of the stretched polypropylene film and then forming a vapor-deposited film on the surface coating layer, adhesion can be improved and gas barrier properties can also be improved.

[0009] Furthermore, it has been discovered that if the laminate described above is used as a lid material for a packaging container, deterioration of gas barrier properties and heat seal properties can be effectively suppressed even during heat treatments such as retort treatment and boiling treatment (suitability for retort treatment, suitability for boiling treatment).

[0010] The present invention was made based on such findings, and the problem to be solved by the present invention is to provide a laminate that can be suitably used for mono-material packaging containers, particularly as a lid material, and that, when used as a lid material, can maintain gas barrier properties and adhesion even during retort treatment or boiling treatment.

[0011] Another problem to be solved by the present invention is to provide a laminate that can be used as a lid material and that can maintain gas barrier properties and adhesiveness even during retort treatment or boiling treatment. [Means for solving the problem]

[0012] In a first aspect, the present invention provides a laminate comprising: At least a first substrate, a vapor-deposited film, and a sealant layer are included, the first base material includes a polypropylene resin layer and a surface resin layer provided on one surface of the polypropylene resin layer, the vapor-deposited film is provided on a surface resin layer of the first substrate, The first substrate has been subjected to a stretching treatment, the surface resin layer contains a resin material having a melting point of 180°C or higher, the vapor-deposited film is composed of an inorganic oxide, the sealant layer comprises a polyolefin having a melting point of 110°C or higher; The sealant layer is a laminate, wherein the polyolefin is an easy-peel sealant layer that is polypropylene.

[0013] In one embodiment, the surface resin layer is provided on the polypropylene resin layer.

[0014] In one embodiment, the first base material includes an adhesive resin layer between the polypropylene resin layer and the surface resin layer, the adhesive resin layer is provided on the polypropylene resin layer, The surface resin layer is provided on the adhesive resin layer.

[0015] In one embodiment, the surface resin layer includes a resin material having a melting point of 180°C or higher and 265°C or lower.

[0016] In one embodiment, the resin material of the surface resin layer has a melting point TA, The polypropylene of the polypropylene resin layer has a melting point TB, The difference between the melting point TA and the melting point TB is 20°C or more and 80°C or less.

[0017] In one embodiment, the resin material of the surface resin layer is made of a polymer having a polar group.

[0018] In one embodiment, the resin material of the surface resin layer is one or more resin materials selected from nylon 6, nylon 6,6, MXD nylon, and amorphous nylon.

[0019] In one embodiment, the ratio of the thickness of the surface resin layer to the total thickness of the first base material is 1% or more and 10% or less.

[0020] In one embodiment, the first substrate is a co-extruded film.

[0021] In a second aspect, the present invention provides a laminate comprising: At least a first substrate, a vapor-deposited film, and a sealant layer are included, the first base material includes a polypropylene resin layer and a surface coating layer provided on one surface of the polypropylene resin layer, the vapor-deposited film is provided on a surface coating layer of the first substrate, The first substrate has been subjected to a stretching treatment, the surface coating layer contains a resin material having a polar group, the vapor-deposited film is composed of an inorganic oxide, the sealant layer is an easy-peel layer containing a polyolefin having a melting point of 110°C or higher, The laminate is characterized in that the polyolefin is polypropylene.

[0022] In one embodiment, the resin material of the surface coating layer is one or more resin materials selected from polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, nylon 6, nylon 6,6, MXD nylon, amorphous nylon, and polyurethane.

[0023] In one embodiment, the surface coating layer is a layer formed using a water-based emulsion or a solvent-based emulsion.

[0024] In one embodiment, the ratio of the thickness of the surface coating layer to the total thickness of the first substrate is 0.08% or more and 20% or less.

[0025] In one embodiment, the surface coating layer has a thickness of 0.02 μm or more and 10 μm or less.

[0026] In one embodiment, the easy peel sealant layer has an islands-in-a-sea structure, The sea-island structure includes a sea portion made of polypropylene and an island portion made of high-density polyethylene.

[0027] In one embodiment, the laminate further comprises a second substrate.

[0028] In one embodiment, the second substrate comprises polypropylene.

[0029] In one embodiment, the first substrate and the deposited film are located between the second substrate and the sealant layer.

[0030] In one embodiment, the laminate includes an intermediate layer between the vapor-deposited film and the sealant layer, The intermediate layer is the second substrate.

[0031] In one embodiment, the intermediate layer is made of a polypropylene resin film that has been subjected to a stretching treatment.

[0032] In one embodiment, a barrier coat layer is further provided between the vapor-deposited film and the sealant layer.

[0033] In one embodiment, the barrier coat layer is a gas barrier coating film of a mixture of a metal alkoxide and a water-soluble polymer, or a gas barrier coating film of a mixture of a metal alkoxide, a water-soluble polymer, and a silane coupling agent.

[0034] The present invention is a lid material comprising the laminate.

[0035] The present invention is a packaging container using the lid material, in which the sealant layer of the lid material is heat-sealed in a state where it is overlapped so as to contact the opening of the container body. [Effects of the Invention]

[0036] According to the present invention, even when a stretched polypropylene resin film is used as the substrate, it is possible to obtain a laminate having high adhesion to a vapor-deposited film and excellent gas barrier properties. Furthermore, since the heat seal layer is an easy-peel heat seal layer containing polypropylene, it is suitable as a mono-material packaging material and can be used as a lid material that can maintain gas barrier properties and adhesion even during retort treatment or boiling treatment. [Brief explanation of the drawings]

[0037] [Figure 1] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 2] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 3] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 4] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 5] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 6] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 7] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 8] FIG. 1 is a plan view showing an example of a loop stiffness measuring device. [Figure 9] FIG. 9 is a cross-sectional view of the loop stiffness measuring device of FIG. 8 taken along line VV. [Figure 10] FIG. 10 is a diagram illustrating a process of attaching a test piece to a loop stiffness measuring instrument. [Figure 11]FIG. 10 is a diagram illustrating a step of forming a loop portion in a test piece. [Figure 12] FIG. 10 is a diagram illustrating a process of applying a load to a loop portion of a test piece. [Figure 13] FIG. 10 is a diagram illustrating a process of applying a load to a loop portion of a test piece. [Figure 14] FIG. 10 is a diagram illustrating a process of applying a load to a loop portion of a test piece. [Figure 15] FIG. 1 is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. [Figure 16] FIG. 1 is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus. [Figure 17] FIG. 10 is a schematic cross-sectional view showing another embodiment of a vapor deposition apparatus. [Figure 18] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 19] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 20] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 21] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 22] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 23] 1 is a perspective view showing one embodiment of a container provided with a lid material of the present invention. [Figure 24] 1 is a schematic cross-sectional view showing one embodiment of a container provided with a lid material of the present invention. [Figure 25] FIG. 2 is a schematic diagram showing an example of a method for measuring laminate strength. [Figure 26] FIG. 2 is a schematic diagram showing an example of a method for measuring laminate strength. [Figure 27] FIG. 10 is a graph showing the change in tensile stress relative to the distance between a pair of grippers that pull the substrate side and the sealant layer side to measure the laminate strength. [Figure 28] FIG. 10 is a diagram showing an example of a method for measuring puncture strength. DETAILED DESCRIPTION OF THE INVENTION

[0038] [Laminate in the first embodiment] As shown in FIG. 1, a laminate 10A of the present invention includes a first substrate 11A, a vapor-deposited film 12A, and a sealant layer 13A, and the first substrate 11A includes at least a polypropylene resin layer 14A and a surface resin layer 15A. In one embodiment of the present invention, the laminate 10A may further include a barrier coat layer 16A between the vapor-deposited film 12A and the sealant layer 13A, as shown in FIG. In one embodiment of the present invention, the first base material 11A may include an adhesive resin layer 17A between the polypropylene resin layer 14A and the surface resin layer 15A, as shown in FIG. In one embodiment of the present invention, the laminate 10A may include a first substrate 11A, a vapor-deposited film 12A, a barrier coating layer 16A provided on the vapor-deposited film 12A, and a sealant layer 13A, as shown in Fig. 4. The first substrate 11A may include a polypropylene resin layer 14A, an adhesive resin layer 17A, and a surface resin layer 15A, and the adhesive resin layer 17A may be provided between the polypropylene resin layer 14A and the surface resin layer 15A. In one embodiment of the present invention, the laminate may further include a second substrate. When the laminate includes a second substrate, the laminate 10A may include, in order, a second substrate 18A, a vapor-deposited film 12A, a first substrate 11A, and a sealant layer 13A, as shown in Fig. 5; or may include, in order, a second substrate 18A, a first substrate 11A, a vapor-deposited film 12A, and a sealant layer 13A, as shown in Fig. 6; or may include, in order, a first substrate 11A, a vapor-deposited film 12A, a second substrate 18A, and a sealant layer 13A, as shown in Fig. 7. The second substrate 18A in the laminates 10A of Figs. 5 and 6 and the first substrate 11A in the laminate 10A of Fig. 7 may be located as the outermost layer of the laminate 10A. In one embodiment of the present invention, the laminate 10A may include an adhesive layer (not shown) between any of the vapor-deposited film, the sealant layer, the first substrate, and the second substrate. In other embodiments, the laminate of the present invention may include an intermediate layer between the vapor-deposited film and the sealant layer, and the intermediate layer may be the second substrate.

[0039] The haze value of the laminate is preferably 20% or less, and more preferably 5% or less, which can improve the transparency of the laminate. In this specification, the haze value of the laminate is measured in accordance with JIS K 7105:1981 using a haze meter (Murakami Color Research Laboratory Co., Ltd.).

[0040] In the laminate of the first aspect, the lamination strength between the first substrate and the vapor-deposited film is preferably 3 N or more, more preferably 4 N or more, and even more preferably 5.5 N or more, per 15 mm width. The upper limit of the lamination strength of the laminate may be 20 N or less. The method for measuring the lamination strength of the laminate will be explained in the examples below.

[0041] The tensile strength of the laminate in one direction may be 30 MPa or more, or 35 MPa or more. The tensile strength of the laminate in one direction may be 70 MPa or less, or 50 MPa or less. The one direction of the laminate may be the machine direction (MD). The tensile strength of the laminate in a direction perpendicular to the one direction may be 40 MPa or more, or 60 MPa or more. The tensile strength of the laminate in a direction perpendicular to the one direction may be 150 MPa or less, or 100 MPa or less. The direction perpendicular to the one direction may be the transverse direction (TD) of the laminate. In this specification, the tensile strength of the laminate is measured in accordance with JIS K7127: 1999. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Co., Ltd. can be used. The test specimens used are rectangular laminates cut from the laminate with a width of 10 mm and a length of 150 mm. The distance between the pair of chucks holding the test specimens at the start of the measurement is 50 mm, and the tensile speed is 300 mm / min. Unless otherwise specified, the environment during tensile strength measurement is a temperature of 23°C and a relative humidity of 50%.

[0042] The loop stiffness in one direction of the laminate may be 30 mN or more, 50 mN or more, or 70 mN or more. The loop stiffness in one direction of the laminate may be 200 mN or less, 150 mN or less, or 120 mN or less. The one direction of the laminate may be the machine direction (MD). The loop stiffness of the laminate in a direction perpendicular to the one direction may be 30 mN or more, 50 mN or more, or 70 mN or more. The loop stiffness of the laminate in a direction perpendicular to the one direction may be 200 mN or less, 150 mN or less, or 130 mN or less. The direction perpendicular to the one direction may be the transverse direction (TD) of the laminate.

[0043] Loop stiffness is a parameter that indicates the stiffness of a laminate. A method for measuring loop stiffness will be described below with reference to Figs.

[0044] FIG. 8 is a plan view showing the test piece 20 and the loop stiffness measuring device 25, and FIG. 9 is a cross-sectional view of the test piece 20 and the loop stiffness measuring device 25 of FIG. 8 taken along line VV. The test piece 20 is a rectangular laminate having long and short sides. In this specification, the length X1 of the long side of the test piece 20 is 150 mm, and the length X2 of the short side is 15 mm. As the loop stiffness measuring device 25, for example, No. 581 Loop Stiffness Tester (registered trademark) LOOP STIFFNESS TESTER DA type manufactured by Toyo Seiki Seisakusho, Ltd. can be used. The length X1 of the long side of the test piece 20 can be adjusted as long as the test piece 20 can be gripped by a pair of chucks 26, which will be described later.

[0045] The loop stiffness measuring device 25 has a pair of chuck portions 26 for gripping a pair of ends in the long side direction of the test specimen 20, and a support member 27 for supporting the chuck portions 26. The chuck portions 26 include a first chuck 26A and a second chuck 26B. In the state shown in FIGS. 8 and 9, the test specimen 20 is placed on the pair of first chucks 26A, and the second chuck 26B does not yet grip the test specimen 20 between the first chuck 26A and the second chuck 26B. As will be described later, during measurement, the test specimen 20 is gripped between the first chuck 26A and the second chuck 26B of the chuck portions 26. The second chuck 26B may be connected to the first chuck 26A via a hinge mechanism.

[0046] A method for measuring the loop stiffness of the test specimen 20 using the loop stiffness measuring instrument 25 will be described. First, as shown in FIGS. 8 and 9, the test specimen 20 is placed on the first chuck 26A of a pair of chucks 26 arranged with a gap X3 therebetween. In this specification, the gap X3 is set so that the length of a loop portion 21 (described later, also referred to as the loop length) is 60 mm. The test specimen 20 includes an inner surface 20x located on the first chuck 26A side and an outer surface 20y located opposite the inner surface 20x. When a loop portion 21 (described later) is formed on the test specimen 20, the inner surface 20x is located inside the loop portion 21, and the outer surface 20y is located outside the loop portion 21. Next, as shown in FIG. 10, the second chuck 26B is placed on the test specimen 20 so that the end of the long side of the test specimen 20 is gripped between the first chuck 26A and the second chuck 26B.

[0047] Next, as shown in FIG. 11 , at least one of the pair of chuck portions 26 is slid on the support member 27 in a direction that reduces the distance between the pair of chuck portions 26. This allows a loop portion 21 to be formed on the test piece 20. The test piece 20 shown in FIG. 11 has a loop portion 21, a pair of intermediate portions 22, and a pair of fixing portions 23. The pair of fixing portions 23 are portions of the test piece 20 that are gripped by the pair of chuck portions 26. The pair of intermediate portions 22 are portions of the test piece 20 that are located between the loop portion 21 and the pair of intermediate portions 22. As shown in FIG. 11 , the chuck portion 26 is slid on the support member 27 until the inner surfaces 20x of the pair of intermediate portions 22 come into contact with each other. This allows a loop portion 21 having a loop length of 60 mm to be formed. The loop length of the loop portion 21 is the length of the test piece 20 between position P1 where the surface of one second chuck 26B on the loop portion 21 side intersects with the test piece 20, and position P2 where the surface of the other second chuck 26B on the loop portion 21 side intersects with the test piece 20. If the thickness of the test piece 20 is ignored, the above-mentioned distance X3 is the value obtained by adding 2×t to the length of the loop portion 21, where t is the thickness of the second chuck 26B of the chuck portion 26.

[0048] Next, as shown in FIG. 12, the posture of the chuck portion 26 is adjusted so that the protruding direction Y of the loop portion 21 relative to the chuck portion 26 is horizontal. For example, the posture of the chuck portion 26 supported by the support member 27 is adjusted by moving the support member 27 so that the normal direction of the support member 27 is horizontal. In the example shown in FIG. 12, the protruding direction Y of the loop portion 21 coincides with the thickness direction of the chuck portion. In addition, a load cell 28 is prepared at a position spaced a distance Z1 from the second chuck 26B in the protruding direction Y of the loop portion 21.

[0049] 13, the load cell 28 is moved toward the loop portion 21, and the load cell 28 is brought into contact with the loop portion 12. The distance Z1 is the distance between the load cell 28 and the second chuck 26B of the chuck portion 26.

[0050] 14, the loop portion 21 is pressed by a distance Z2 toward the chuck portion 26 by the load cell 28. In this specification, the distance Z2 is set to 15 mm. Next, as shown in Fig. 14, the load cell 28 is moved a distance Z2 toward the chuck portion 26, and in a state in which the load cell 28 is pressing into the loop portion 21 of the test piece 20, the value of the load applied to the load cell 28 from the loop portion 21 becomes stable, and then the value of the load is recorded. The value of the load thus obtained is taken as the loop stiffness of the laminate constituting the test piece 20. In this specification, unless otherwise specified, the environment during the measurement of loop stiffness is a temperature of 23°C and a relative humidity of 50%.

[0051] The piercing strength of the laminate may be 10 N or more, or 15 N or more. The puncture strength of the laminate is measured in accordance with JIS Z1707 7.4, and the specific measurement method will be explained in the examples below.

[0052] Conventionally, a laminate in which a substrate and a sealant layer are made of different resin materials has been used for a packaging container. However, since it is difficult to separate the substrate and the sealant layer after collecting used packaging containers, the current situation is that such a laminate is not actively recycled. In the present invention, a stretched polypropylene resin film is used as the first substrate, and the sealant layer is a layer containing polypropylene having a melting point of 110°C or higher, and by constructing both from the same material, the recyclability of the laminate when used as a packaging container can be improved.

[0053] From the viewpoint of recyclability, the higher the proportion of polypropylene contained in the sealant layer, the more preferable, as will be described later. When the sealant layer is made of polypropylene, the content of polypropylene relative to the total amount of resin materials contained in the laminate of the present invention is preferably 80% by mass or more, more preferably 95% by mass or more, thereby further improving the recyclability of packaging containers produced using the laminate of the present invention.

[0054] Each layer of the laminate of the present invention will be described below.

[0055] (1st base material) The first substrate comprises at least a polypropylene resin layer and a surface resin layer, and if desired, an adhesive resin layer may be provided between the polypropylene resin layer and the surface resin layer.

[0056] (Polypropylene resin layer) The polypropylene resin layer is made of polypropylene and may have a single-layer structure or a multi-layer structure. By providing the first base material with a polypropylene resin layer, the heat resistance and oil resistance of a packaging container produced using the first base material can be improved.

[0057] The polypropylene resin layer is a film that has been subjected to a stretching treatment. The stretching treatment may be uniaxial stretching or biaxial stretching. The stretching ratio in the machine direction (MD direction) and the transverse direction (TD direction) of the polypropylene resin layer is preferably 2 times or more and 15 times or less, and more preferably 5 times or more and 13 times or less. By setting the stretching ratio to 2 times or more, the strength and heat resistance of the polypropylene resin layer can be further improved, and the printability of the polypropylene resin layer can also be improved. From the viewpoint of the breaking limit of the polypropylene resin layer, the stretching ratio is preferably 15 times or less.

[0058] The polypropylene contained in the polypropylene resin layer may be any of a homopolymer, a random copolymer, and a block copolymer. A polypropylene homopolymer is a polymer of only propylene, a polypropylene random copolymer is a random copolymer of propylene and an α-olefin other than propylene (e.g., ethylene, butene-1, 4-methyl-1-pentene, etc.), and a polypropylene block copolymer is a copolymer having a polymer block made of propylene and a polymer block made of the above-mentioned α-olefin other than propylene. Among these polypropylenes, it is preferable to use a homopolymer or a random copolymer from the viewpoint of transparency. When emphasis is placed on the rigidity and heat resistance of the packaging bag, it is preferable to use a homopolymer, and when emphasis is placed on impact resistance, it is preferable to use a random copolymer. It is also possible to use biomass-derived polypropylene or mechanically or chemically recycled polypropylene.

[0059] 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.

[0060] The polypropylene resin layer may contain a heat seal modifier, which can improve the heat sealability of the polypropylene resin layer and make it easier to produce a packaging container by sealing it with an envelope. The heat seal modifier is not particularly limited as long as it has excellent compatibility with the polypropylene constituting the heat seal layer, and examples thereof include olefin copolymers. Furthermore, a conventionally known heat sealing agent may be applied to the surface of the polypropylene resin layer and then dried.

[0061] The polypropylene resin layer may contain a resin material other than polypropylene, such as polyolefins such as polyethylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamide resins, polyesters, and ionomer resins, as long as the properties of the present invention are not impaired. The polypropylene resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins, as long as the additives do not impair the properties of the present invention.

[0062] The thickness of the polypropylene resin layer is preferably 10 μm or more, more preferably 10 μm or more, and is preferably 50 μm or less, more preferably 40 μm or less. By making the thickness of the polypropylene resin layer 10 μm or more, the strength and heat resistance of the first base material can be further improved. By setting the thickness of the polypropylene resin layer to 50 μm or less, the film-forming properties and processability of the first substrate can be further improved.

[0063] The polypropylene resin layer may have a printed layer on its surface. The image formed on the printed layer is not particularly limited, and may include letters, patterns, symbols, and combinations thereof. The printing layer on the first substrate can be formed using ink derived from biomass, which further reduces the environmental impact. The method for forming the printed layer is not particularly limited, and examples thereof include conventionally known printing methods such as gravure printing, offset printing, and flexographic printing.

[0064] The polypropylene resin layer may be subjected to a surface treatment, which can improve adhesion to the surface coating layer. The surface treatment method is not particularly limited, and examples thereof include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals.

[0065] (Surface resin layer) The first base material has a surface 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), which allows a vapor-deposited film with high adhesion to be formed on the surface resin layer, thereby improving gas barrier properties. Furthermore, as will be described later, packaging containers produced using a laminate having the surface resin layer have high laminate strength. In one embodiment, the surface resin layer may be provided on the polypropylene resin layer, i.e., the surface resin layer may be adjacent to the polypropylene resin layer. In one embodiment, when the first substrate includes an adhesive resin layer between the polypropylene resin layer and the surface resin layer, the adhesive resin layer may be provided on the polypropylene resin layer, and the surface resin layer may be provided on the adhesive resin layer, i.e., the adhesive resin layer may be adjacent to the polypropylene resin layer, and the surface resin layer may be adjacent to the adhesive resin layer.

[0066] 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 adhesiveness of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. From the viewpoint of film-forming properties of the first substrate, 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 transition temperature of plastics). Specifically, the melting point can be determined by measuring a DSC curve using a differential scanning calorimetry (DSC) device at a temperature rise rate of 10°C / min.

[0067] The high-melting-point resin material contained in the surface resin layer has a melting point TA, and the polypropylene contained in the polypropylene resin layer has a melting point TB, and the difference between the melting points TA and TB is preferably 20° C. or more. The difference between the melting points TA and TB is preferably 80° C. or less, and more preferably 60° C. or less. When the difference between the melting point TA and the melting point TB is 20°C or more, the adhesiveness of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. Furthermore, by making the difference between the melting point TA and the melting point TB 80° C. or less, the film-forming properties of the first substrate can be further improved.

[0068] The high-melting-point resin material preferably has a polar group. In the present invention, the polar group refers to a group containing one or more heteroatoms. Examples of polar groups include ester groups, epoxy groups, hydroxyl groups, amino groups, amide groups, carboxyl groups, carbonyl groups, carboxylic anhydride groups, sulfone groups, thiol groups, and halogen groups. Among these, from the viewpoint of the laminate strength of the packaging container, hydroxyl groups, ester groups, amino groups, amide groups, carboxyl groups, and carbonyl groups are preferred, and amide groups are more preferred.

[0069] The high-melting-point resin material is not particularly limited as long as it has a melting point of 180° C. or higher. Examples of high-melting-point resin materials include vinyl resins, polyamides, polyimides, polyesters, (meth)acrylic resins, cellulose resins, polyolefins, and ionomer resins.

[0070] The high-melting-point resin material is particularly preferably a resin material having a melting point of 180° C. or higher and having a polar group, and is preferably polyester or polyamide such as nylon 6, nylon 6,6, MXD nylon, or amorphous nylon. By using such a resin material, the adhesion of the vapor-deposited film formed on the surface resin layer can be significantly improved, and the gas barrier properties thereof can be effectively improved.

[0071] In one embodiment, the high-melting point resin material is preferably polyamide. By using polyamide as the high-melting point resin material, it is possible to suppress the deterioration of gas barrier properties even after bending the laminate, and to improve the heat resistance of the laminate. In addition, it is possible to suppress the deterioration of gas barrier properties even after the laminate is subjected to the retort treatment and boiling treatment described below. It is more preferable that the high-melting point resin material is nylon 6.

[0072] 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.

[0073] The surface resin layer may contain a resin material other than the high-melting-point resin material as long as the characteristics of the present invention are not impaired. The surface resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins, as long as the additives do not impair the properties of the present invention.

[0074] The ratio of the thickness of the surface resin layer to the total thickness of the first base material is preferably 1% or more, and is preferably 10% or less, and more preferably 5% or less. By making the ratio of the thickness of the surface resin layer to the total thickness of the first base material 1% or more, the adhesion of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. By setting the ratio of the thickness of the surface resin layer to the total thickness of the first substrate to 10% or less, the film-forming property and processability of the first substrate can be further improved. Furthermore, as will be described later, the recyclability of packaging containers produced using a laminate of the laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0075] The thickness of the surface resin layer is preferably 0.1 μm or more, and more preferably 5 μm or less, and more preferably 4 μm or less. By making the thickness of the surface resin layer 0.1 μm or more, the adhesion of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. Furthermore, by setting the thickness of the surface resin layer to 5 μm or less, the film-forming property and processability of the first substrate can be further improved, and as will be described later, the recyclability of packaging containers produced using a laminate of the laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0076] (adhesive resin layer) In one embodiment of the present invention, the first base material may include an adhesive resin layer between the polypropylene resin layer and the surface resin layer, thereby improving interlayer adhesion between the polypropylene resin layer and the surface resin layer.

[0077] The adhesive resin layer can be formed from adhesive resins such as polyether, polyester, silicone resin, epoxy resin, polyurethane, vinyl resin, phenolic resin, polyolefin, and acid-modified polyolefin. Among these, from the viewpoint of recyclability, polyolefin and its acid-modified polyolefin are preferred, and polypropylene and its acid-modified polyolefin are particularly preferred. Commercially available adhesive polypropylene can be used, for example, the Admer series manufactured by Mitsui Chemicals, Inc.

[0078] The thickness of the adhesive resin layer is not particularly limited, but can be, for example, 1 μm or more and 15 μm or less. By making the thickness of the adhesive resin layer 1 μm or more, the adhesion between the polypropylene resin layer and the surface resin layer can be further improved. By making the thickness of the adhesive resin layer 15 μm or less, the processability of the first substrate can be improved.

[0079] The first base material composed of the above-mentioned layers is subjected to a stretching treatment. The stretching treatment improves the mechanical strength. The stretching treatment may be uniaxial stretching or biaxial stretching.

[0080] In one embodiment, the first substrate is a co-extruded film. The co-extruded film can be produced by forming a film using a T-die method, an inflation method, or the like, forming a laminated film, and then stretching it. The inflation method is preferred from the viewpoint of productivity, since it allows film formation and stretching to be carried out continuously in one step.

[0081] The stretching ratio of the first substrate in the machine direction (MD) and the cross direction (TD) is preferably 2 times or more, and more preferably 5 times or more. The stretching ratio of the first substrate in the machine direction (MD) and the cross direction (TD) is preferably 15 times or less, and more preferably 13 times or less. By setting the stretching ratio to 2 times or more, the strength of the first substrate can be further improved. Furthermore, the printability of the first substrate can be improved. On the other hand, from the viewpoint of the breaking limit of the first substrate, the stretching ratio is preferably 15 times or less. When the polypropylene resin layer of the first substrate is made heat-sealable to form a packaging container (e.g., a tube) by sealing it into an envelope, the stretching ratio is more preferably 2 times or more and 10 times or less, and particularly preferably 2.5 times or more and 7 times or less.

[0082] In one embodiment, the first substrate is preferably stretched so that its tensile strength in the machine direction (MD) is greater than its tensile strength in the transverse direction (TD). This configuration allows the packaging container made from the laminate of the present invention to be highly tearable in one direction. The tensile strength of the first substrate in the machine direction (MD) is preferably 1.05 times or more, more preferably 1.10 times or more, and even more preferably 1.2 times or more, the tensile strength in the cross direction (TD). The tensile strength in the machine direction (MD direction) can be, for example, 200 MPa or more and 300 MPa or less. In this specification, the tensile strength of the first substrate is measured in accordance with JIS K7127: 1999. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Co., Ltd. can be used. The test specimen can be a rectangular film cut from the first substrate, 15 mm wide and 150 mm long. 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. Unless otherwise specified, the environment during tensile strength measurement is a temperature of 23°C and a relative humidity of 50%.

[0083] The surface resin layer constituting the first base material may be subjected to a surface treatment, which can improve adhesion to the adjacent layer (vapor-deposited film). The surface treatment method is not particularly limited, and examples thereof include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals.

[0084] (evaporated film) The laminate of the present invention has a vapor-deposited film made of an inorganic oxide on the surface resin layer. That is, the vapor-deposited film is adjacent to the surface resin layer. This can impart gas barrier properties, specifically oxygen barrier properties and water vapor barrier properties, to the laminate. Furthermore, weight loss of contents filled in a packaging container made using the laminate of the present invention can be suppressed.

[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, silicon carbide oxide (carbon-containing silicon oxide), etc. Among these, silica, silicon carbide oxide, and alumina are preferred, and silica is particularly preferred from the viewpoint that no aging treatment is required after forming the vapor-deposited film.

[0086] In one embodiment, the inorganic oxide is more preferably carbon-containing silicon oxide, since this can prevent a decrease in gas barrier properties even after the laminate is bent.

[0087] The thickness of the vapor-deposited film is preferably 1 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more. The thickness of the vapor-deposited film is preferably 150 nm or less, more preferably 60 nm or less, and even more preferably 40 nm or less. By making the thickness of the vapor-deposited film 1 nm or more, the oxygen barrier property and water vapor barrier property of the laminate can be further improved. On the other hand, by making the thickness of the vapor-deposited film 150 nm or less, the occurrence of cracks in the vapor-deposited film can be prevented. Furthermore, as long as the thickness of the vapor-deposited film is within the above range, the recyclability of the laminate when used as a packaging container is not impaired.

[0088] The deposition film can be formed by a conventionally known method, for example, physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, and ion plating, and chemical vapor deposition (CVD) methods such as plasma chemical vapor deposition, thermal chemical vapor deposition, and photochemical vapor deposition.

[0089] 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. In the case of a multilayer film, each layer may be made of the same material or different materials. Furthermore, each layer may be formed by the same method or different methods.

[0090] A plasma-assisted vacuum film-forming device can be used as the device used in the method for forming a vapor-deposited film by the PVD method. An embodiment of a method for forming a vapor-deposited film using a plasma-assisted vacuum film-forming apparatus will be described below.

[0091] In one embodiment of the present invention, as shown in Figures 15 and 16, the vacuum film formation apparatus includes a vacuum vessel A, an unwinding section B, a film formation drum C, a winding section D, a transport roll E, an evaporation source F, a reactive gas supply section G, an adhesion-proof box H, an evaporation material I, and a plasma gun J. 15 is a schematic cross-sectional view of the vacuum film-forming apparatus in the XZ plane direction, and FIG. 16 is a schematic cross-sectional view of the vacuum film-forming apparatus in the XY plane direction.

[0092] 15, the first substrate 11A to be wound around the film-forming drum C is placed in the upper part of the vacuum chamber A with its surface resin layer surface facing downward, and an electrically grounded deposition-protective box H is placed below the film-forming drum C in the vacuum chamber A. An evaporation source F is placed on the bottom surface of the deposition-protective box H. The film-forming drum C is placed in the vacuum chamber A so that the surface resin layer surface of the first substrate 11A wound around the film-forming drum C is located in a position facing the upper surface of the evaporation source F with a certain gap between them.

[0093] Further, transport rolls E are arranged 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 evaporation material I and is equipped with a heating device (not shown). The reactive gas supply unit G is a portion that supplies a reactive gas (oxygen, nitrogen, helium, argon, a mixed gas of these, etc.) that reacts with the evaporated deposition material.

[0094] The vapor deposition material I is heated and evaporated from the evaporation source F and directed onto the surface resin layer of the first substrate 11A, and simultaneously, plasma is also directed onto the surface resin layer from the plasma gun J, thereby forming a vapor deposition film. Details of this formation method are disclosed in JP 2011-214089 A.

[0095] The plasma generating device used in plasma chemical vapor deposition can be a device that generates high-frequency plasma, pulsed wave plasma, microwave plasma, or the like. It is also possible to use a device with two or more film formation chambers. It is preferable that the device is equipped with a vacuum pump so that each film formation chamber can be maintained at a vacuum. The degree of vacuum in each deposition chamber is 1×10 Pa or more. -6 It is preferable that the pressure is 0.01 Pa or less. An embodiment of a method for forming a vapor-deposited film using a plasma generating device will be described below.

[0096] First, the first substrate is sent into the film-forming chamber and transported onto the cooling electrode drum at a predetermined speed via an auxiliary roll. Next, a mixed gas composition containing a film-forming monomer gas containing an inorganic oxide, oxygen gas, an inert gas, etc. is supplied from the gas supply device into the film-forming chamber, and plasma is generated on the surface resin layer by glow discharge, which is then irradiated to form a vapor-deposited film containing an inorganic oxide on the surface resin layer. Details of this formation method are disclosed in JP 2012-076292 A.

[0097] FIG. 17 is a schematic diagram showing the configuration of a plasma enhanced chemical vapor deposition apparatus used in the CVD method.

[0098] In one embodiment, as shown in FIG. 17, a plasma enhanced chemical vapor deposition apparatus unwinds a first substrate 11A from a winding section B1 located inside a vacuum vessel A1. The first substrate 11A is then transported at a predetermined speed onto the circumferential surface of a cooling electrode drum C1 via a transport roll E1. Oxygen, nitrogen, helium, argon, and a mixture thereof are supplied from a reactive gas supply G1, and a film-forming monomer gas and other gases are supplied from a raw material gas supply I1. A vapor deposition mixed gas composition consisting of these components is adjusted and introduced into the vacuum vessel A1 through a raw material supply nozzle H1. A glow discharge plasma F1 is then generated on the surface resin layer of the first substrate 11A transported onto the circumferential surface of the cooling electrode drum C1, and this plasma is irradiated to form a vapor deposition film. A predetermined power is applied to the cooling electrode drum C1 from a power source K1 located outside the vacuum vessel A1. A magnet J1 is positioned near the cooling electrode drum C1 to promote plasma generation. Next, after forming the vapor-deposited film, the first base material 11A is wound up at a predetermined winding speed by a winding section D1 via a transport roll E1. In the drawing, L1 represents a vacuum pump.

[0099] As an apparatus used in the method for forming a vapor-deposited film, a continuous vapor-deposited film-forming apparatus equipped with a plasma pretreatment chamber and a film-forming chamber can be used.

[0100] An embodiment of a method for forming a vapor-deposited film using the apparatus will be described below. First, in a plasma pretreatment chamber, plasma is irradiated from a plasma supply nozzle onto a surface resin layer of a first substrate. Next, in a film formation chamber, a vapor deposition film is formed on the plasma-treated surface resin layer. Details of this formation method are disclosed in International Publication WO2019 / 087960.

[0101] The surface of the deposited film is preferably subjected to the above-mentioned surface treatment, which can improve adhesion to adjacent layers.

[0102] In the laminate of the present invention, the vapor-deposited film is preferably a vapor-deposited film formed by a CVD method, and more preferably a carbon-containing silicon oxide vapor-deposited film formed by a CVD method, which can suppress deterioration of the gas barrier property even after the laminate is bent.

[0103] The carbon-containing silicon oxide vapor-deposited film contains silicon, oxygen, and carbon. In the carbon-containing silicon oxide vapor-deposited film, the carbon content C is preferably 3% or more, more preferably 5% or more, and even more preferably 10% or more, relative to the total of the three elements silicon, oxygen, and carbon (100%). In the carbon-containing silicon oxide vapor-deposited film, the carbon content C is preferably 50% or less, more preferably 40% or less, and even more preferably 35% or less, relative to the total of the three elements silicon, oxygen, and carbon (100%). By setting the carbon content C in the carbon-containing silicon oxide vapor-deposited film within the above range, it is possible to prevent the gas barrier properties from decreasing even after the laminate is bent. In this specification, the ratio of each element is based on moles.

[0104] In one embodiment of the carbon-containing silicon oxide vapor-deposited film, the silicon content Si is preferably 1% or more, more preferably 3% or more, and even more preferably 8% or more, relative to 100% of the total of the three elements silicon, oxygen, and carbon. The silicon content Si is preferably 45% or less, more preferably 38% or less, and even more preferably 33% or less, relative to 100% of the total of the three elements silicon, oxygen, and carbon. In one embodiment of the carbon-containing silicon oxide vapor-deposited film, the oxygen ratio O is preferably 10% or more, more preferably 20% or more, and even more preferably 25% or more, relative to the total of the three elements silicon, oxygen, and carbon (100%), and is preferably 70% or less, more preferably 65% ​​or less, and even more preferably 60% or less. By setting the silicon ratio Si and oxygen ratio O in the carbon-containing silicon oxide vapor-deposited film within the above ranges, the deterioration of the gas barrier properties can be further suppressed even after the laminate is bent.

[0105] In one embodiment of the carbon-containing silicon oxide vapor-deposited film, the oxygen ratio O is preferably higher than the carbon ratio C, and the silicon ratio Si is preferably lower than the carbon ratio C. The oxygen ratio O is preferably higher than the silicon ratio Si, that is, the ratios preferably decrease in the order of ratio O, ratio C, and ratio Si. This makes it possible to further suppress deterioration in gas barrier properties even after the laminate is bent.

[0106] The proportions C, Si, and O in the carbon-containing silicon oxide vapor-deposited film can be 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] Spectral collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): approx. 6 mm diameter Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching range: 10mmφ Ion sputtering time: 30 seconds, and the spectrum was collected.

[0107] (barrier coat layer) In one embodiment of the present invention, a barrier coating layer may be provided on the vapor-deposited film. By forming a barrier coating layer on the surface of the vapor-deposited film, the oxygen barrier property and water vapor barrier property of the laminate are further improved.

[0108] In one embodiment, the barrier coat layer contains a gas barrier resin such as ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol (PVA), polyacrylonitrile, polyamides such as nylon 6, nylon 6,6, and polymetaxylylene adipamide (MXD6), polyester, polyurethane, and (meth)acrylic resin. Among these, polyvinyl alcohol is preferred from the viewpoint of oxygen barrier property and water vapor barrier property. Furthermore, by including polyvinyl alcohol in the barrier coat layer, the occurrence of cracks in the vapor-deposited film can be effectively prevented.

[0109] The content of the gas barrier resin in the barrier coat layer is preferably 50% by mass or more, more preferably 75% by mass or more. By making the content of the gas barrier resin in the barrier coat layer 50% by mass or more, the oxygen barrier property and water vapor barrier property can be further improved. The content of the gas barrier resin in the barrier coat layer is preferably 95% by mass or less, more preferably 90% by mass or less.

[0110] The barrier coat layer may contain additives such as those exemplified in the description of the first substrate, as long as the additives do not impair the characteristics of the present invention.

[0111] The thickness of the barrier coat layer is preferably 0.01 μm or more, more preferably 0.1 μm or more. The thickness of the barrier coat layer is preferably 10 μm or less, more preferably 5 μm or less. By making the thickness of the barrier coat layer 0.01 μm or more, the oxygen barrier property and water vapor barrier property of the laminate can be further improved. On the other hand, by making the thickness of the barrier coat layer 10 μm or less, the processability of the laminate can be improved. Furthermore, as long as the thickness of the barrier coat layer is within the above range, recycling suitability is not impaired even when a different material other than polypropylene is used.

[0112] The barrier coat layer can be formed by dissolving or dispersing the gas barrier resin in water or an appropriate solvent, applying the solution, and drying. Alternatively, the barrier coat layer can be formed by applying a commercially available barrier coating agent and drying it.

[0113] In another embodiment, the barrier coat layer is a gas barrier coating film containing at least one resin composition such as a hydrolysate of a metal alkoxide or a hydrolysis condensate of a metal alkoxide obtained by polycondensing 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, an organic solvent, etc. In one embodiment, the gas barrier coating film is a gas barrier coating film of a mixture of a metal alkoxide and a water-soluble polymer, or a gas barrier coating film of a mixture of a metal alkoxide, a water-soluble polymer, and a silane coupling agent. By providing such a barrier coating layer on the vapor-deposited film, it is possible to effectively prevent cracks from occurring in the vapor-deposited film.

[0114] In one embodiment, the metal alkoxide is represented by the following general formula: R 1 n M(OR 2 ) m (wherein, R 1 , R 2 each 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.

[0115] As the metal atom M, for example, silicon, zirconium, titanium, aluminum, etc. can be used. R 1 and R 2 Examples of the organic group represented by the formula include alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and an i-butyl group.

[0116] Examples of metal alkoxides that satisfy the above general formula include tetramethoxysilane (Si(OCH3)4), tetraethoxysilane (Si(OC2H5)4), tetrapropoxysilane (Si(OC3H7)4), and tetrabutoxysilane (Si(OC4H9)4).

[0117] It is preferable to use a silane coupling agent together with the metal alkoxide. As the silane coupling agent, known organoalkoxysilanes containing organic reactive groups can be used, but organoalkoxysilanes having epoxy groups are particularly preferred. Examples of organoalkoxysilanes having epoxy groups include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0118] Two or more of the above silane coupling agents may be used, and the silane coupling agent is preferably used in an amount of about 1 to 20 parts by mass per 100 parts by mass of the total amount of the metal alkoxides.

[0119] As the water-soluble polymer, polyvinyl alcohol and ethylene-vinyl alcohol copolymer are preferred, and from the viewpoints of oxygen barrier property, water vapor barrier property, water resistance and weather resistance, it is preferred to use these in combination.

[0120] 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 the metal alkoxide. By adjusting 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 the metal alkoxide, the oxygen barrier property and water vapor barrier property of the laminate can be further improved. Also, by adjusting 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 the metal alkoxide, the film formability of the gas barrier coating film can be improved.

[0121] In the gas barrier coating film, the ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) is preferably 4.5 or less, more preferably 3.5 or less, by mass. The ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) is preferably 1.0 or more, more preferably 1.7 or more, by mass. By setting the ratio of metal alkoxide to water-soluble polymer to 4.5 or less, it is possible to suppress the deterioration of gas barrier properties even after bending the laminate. By setting the ratio of metal alkoxide to water-soluble polymer to be 1.0 or more, the heat resistance of the laminate can be improved, and the deterioration of the gas barrier properties of the laminate can be suppressed even after retort treatment and boiling treatment. The above ratio is a solid content ratio.

[0122] On the surface of the gas barrier coating film, the ratio of silicon atoms to carbon atoms (Si / C) measured by X-ray photoelectron spectroscopy (XPS) is preferably 1.60 or less, more preferably 1.35 or less, and preferably 0.50 or more, more preferably 0.90 or more. By setting the ratio of silicon atoms to carbon atoms to 1.60 or less, it is possible to suppress the deterioration of the gas barrier properties even after the laminate is bent. By setting the silicon atom to carbon atom ratio to 0.50 or more, the heat resistance of the laminate can be improved, and the deterioration of the gas barrier properties of the laminate can be suppressed even after the laminate is subjected to retort treatment and boiling treatment. The above range of the ratio of silicon atoms to carbon atoms can be achieved by appropriately adjusting the ratio of metal alkoxide to water-soluble polymer. In this specification, the ratio of silicon atoms to carbon atoms is based on moles.

[0123] The ratio of silicon atoms to carbon atoms by X-ray photoelectron spectroscopy (XPS) can be measured by narrow scan analysis under the following measurement conditions. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectral collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): approx. 6 mm diameter Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching range: 10mmφ Ion sputtering time: 30 seconds + 30 seconds + 60 seconds (total 120 seconds) and spectrum was collected.

[0124] The thickness of the gas barrier coating film is preferably 0.01 μm or more, more preferably 0.1 μm or more. The thickness of the gas barrier coating film is preferably 100 μm or less, more preferably 50 μm or less. This allows for improved oxygen barrier properties and water vapor barrier properties while maintaining recyclability. By making the thickness of the gas barrier coating film 0.01 μm or more, the oxygen barrier property and water vapor barrier property of the laminate can be improved, and 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 produced using a laminate of the laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0125] The gas barrier coating film can be formed by applying a composition containing the above-mentioned materials by a conventionally known means such as roll coating using a gravure roll coater or the like, spray coating, spin coating, dipping, brush coating, bar coating, or applicator coating, and then polycondensing the composition by a sol-gel method. The sol-gel catalyst is preferably an acid or an amine compound. As the amine compound, a tertiary amine that is substantially insoluble in water and soluble in an organic solvent is preferred, such as N,N-dimethylbenzylamine, tripropylamine, tributylamine, tripentylamine, etc. Among these, N,N-dimethylbenzylamine is preferred. The sol-gel catalyst is preferably used in the range of 0.01 to 1.0 part by mass, more preferably 0.03 to 0.3 part by mass, per 100 parts by mass of the metal alkoxide. By using a sol-gel catalyst in an amount of 0.01 part by mass or more per 100 parts by mass of metal alkoxide, the catalytic effect can be improved, and by using a sol-gel catalyst in an amount of 1.0 part by mass or less per 100 parts by mass of metal alkoxide, the thickness of the gas barrier coating film formed can be made uniform.

[0126] The composition may further contain an acid, which is used as a catalyst in the sol-gel process, mainly for the hydrolysis of metal alkoxides, silane coupling agents, and the like. Examples of acids that can be used include mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid, and organic acids such as acetic acid and tartaric acid. The amount of acid used is preferably 0.001 mol or more and 0.05 mol or less based on the total molar amount of the metal alkoxide and the alkoxide portion (e.g., silicate portion) of the silane coupling agent. The catalytic effect can be improved by using an acid in an amount of 0.001 mole or more relative to the total molar amount of the metal alkoxide and the alkoxide portion (e.g., silicate portion) of the silane coupling agent.Furthermore, the thickness of the gas barrier coating film formed can be made uniform by using an acid in an amount of 0.05 mole 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.

[0127] The composition preferably contains water in an amount of 0.1 to 100 moles, more preferably 0.8 to 2 moles, per mole of the total molar amount of the metal alkoxides. By adjusting the water content to 0.1 mol or more per mol of the total molar amount of metal alkoxides, the oxygen barrier property and water vapor barrier property of the laminate of the present invention can be improved, and by adjusting the water content to 100 mol or more per mol of the total molar amount of alkoxides, the hydrolysis reaction can be carried out quickly.

[0128] The composition may contain an organic solvent, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, or n-butanol.

[0129] An embodiment of the method for forming a gas barrier coating film will be described below.

[0130] First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and optionally a silane coupling agent, etc. A polycondensation reaction gradually proceeds in the composition. Next, the composition is applied onto the vapor-deposited film by the above-mentioned conventionally known method and dried, which further promotes the polycondensation reaction of the metal alkoxide and the water-soluble polymer (and the silane coupling agent, if the composition contains one) to form a composite polymer layer. Finally, the composition is heated at a temperature of 20° C. to 250° C., preferably 50° C. to 220° C., for 1 second to 10 minutes to form a gas barrier coating film.

[0131] A printed layer may be formed on the surface of the barrier coat layer, and the method for forming the printed layer is as described above.

[0132] (sealant layer) The sealant layer contains a polyolefin having a melting point of 110° C. or higher, which improves the heat resistance of the laminate. In addition, packaging containers made using the laminate have heat resistance. In this specification, "a polyolefin having a melting point of 110°C or higher" means a polyolefin having a maximum peak temperature of 110°C or higher in DSC.

[0133] The sealant layer constituting the laminate of the present invention is an easy-peel sealant layer in which the polyolefin having a melting point of 110°C or higher is polypropylene. That is, the sealant layer is an easy-peel sealant layer containing polypropylene. The inclusion of polypropylene improves recyclability because it is the same material as the substrate, and also improves retort treatment suitability and boiling treatment suitability when used as a packaging material (particularly, a lid material). Retort treatment is a process in which the contents are filled into a packaging container, sealed with a lid material, and then heated under pressure using steam or heated hot water, for example, at 121°C for 3 minutes. Boiling treatment is a process in which the contents are filled into a packaging container, sealed with a lid material, and then heated using heated hot water, for example, at 90°C for 3 minutes.

[0134] The easy-peel sealant layer refers to the ease of opening after the lid material has been heat-sealed and sealed, and includes, for example, a cohesive peeling type, an interlayer peeling type, and an interface peeling type. Among these, the cohesive peeling type is preferably used from the viewpoint of enabling thermal sterilization treatment such as retort treatment or boiling treatment when used as a lid material. Specifically, easy-peel properties can be imparted by forming a sealant layer from a mixture of polypropylene and a resin that is incompatible with polypropylene.

[0135] The polypropylene used in the sealant layer may be any of a homopolymer, a random copolymer, and a block copolymer. Among these, from the viewpoint of suitability for retort processing and boiling processing, a block copolymer having a propylene block and an ethylene block or a random copolymer of propylene and ethylene is preferred. For example, a copolymer having a density of 0.900 g / cm 3 A block copolymer or random copolymer having a relatively low melt viscosity, in which the melt flow rate (MFR) at 230° C. is 5 g / 10 min or more and 30 g / 10 min or less, can be suitably used. From the viewpoint of easy peelability, a propylene-ethylene random copolymer is preferred as the polypropylene.

[0136] "Propylene-ethylene block copolymer" means a polymer having the structural formula shown in formula (1) below: In formula (1), m1, m2, and m3 represent integers of 1 or greater.

[0137] [ka]

[0138] "Propylene-ethylene random copolymer" means a polymer having the structural formula shown in formula (2) below: In formula (2), m and n represent integers of 1 or greater.

[0139] [ka]

[0140] Examples of resins that are incompatible with polypropylene include polyethylene and polystyrene, but high-density polyethylene is preferably used for the sealant layer according to the second embodiment. By forming the sealant layer from a mixture of polypropylene and high-density polyethylene, a sea-island structure is developed in the sealant layer, making it possible to impart easy peelability. In one embodiment, the islands-in-a-sea structure includes a sea portion made of polypropylene and an island portion made of high-density polyethylene.

[0141] The above-mentioned sea-island structure can be produced by adjusting the blend ratio of polypropylene and high-density polyethylene. The sea-island structure can be produced when the blend ratio of polypropylene is 40 to 80 parts by mass, preferably 60 to 80 parts by mass, and the blend ratio of high-density polyethylene is 20 to 60 parts by mass, preferably 20 to 40 parts by mass. However, from the viewpoints of recyclability, retort treatment suitability, and boiling treatment suitability, a higher proportion of polypropylene is preferred.

[0142] The sealant layer may contain a heat seal modifier or additives as long as the properties of the present invention are not impaired. The heat seal modifier is not particularly limited as long as it has excellent compatibility with the polypropylene constituting the heat seal layer, but examples thereof include olefin copolymers. The additives may be the same as those described above.

[0143] The thickness of the sealant layer is preferably 15 μm or more, more preferably 20 μm or more. The thickness of the sealant layer in the second embodiment is preferably 100 μm or less, more preferably 70 μm or less. By setting the thickness of the sealant layer within the above range, it is possible to improve the adhesive strength with the container body when the laminate is used as a lid material while maintaining the processability when manufacturing the laminate, and to suppress damage to the packaging container (such as peeling of the lid material from the container body) even when subjected to impact, for example, by dropping. In addition, it is possible to further improve the retort treatment suitability and boiling treatment suitability of the packaging container when used as a lid material.

[0144] The sealant layer may have a single layer structure or a multi-layer structure. Cohesive failure type easy peel sealant layers often consist of two or three layers. The easy-peel sealant layer may include other layers as long as it has the above-described layer having easy-peel properties on the surface of the laminate. That is, the easy-peel sealant layer may have a multilayer structure including a layer having easy-peel properties and other layers. The easy-peel sealant layer preferably has such a multilayer structure including two or more layers, since it can maintain both good adhesion with the layer located on the first base layer side and good easy-peel properties. A specific example of an easy-peel sealant layer having a multi-layer structure will be described below, with the layer having easy-peel properties referred to as layer A and the other layer referred to as layer B.

[0145] Layer A in the easy-peel sealant layer contains polypropylene as a main component and has a density of 0.940 g / cm 3 The polyethylene contained in Layer A is one of the above polyethylenes. When Layer A contains such a polyethylene, the retort treatment suitability and boiling treatment suitability of the laminate can be improved. Polyethylenes with the above density tend to have a relatively low MFR. The phrase "containing polypropylene as a main component" means that Layer A contains more than 50% by mass of polypropylene.

[0146] In Layer A, the polypropylene content is preferably 50% by mass or more, and more preferably 60% by mass or more. The polypropylene content is preferably 90% by mass or less, and more preferably 80% by mass or less. This can further improve the retort treatment suitability and boiling treatment suitability of the laminate.

[0147] In layer A, the density is 0.940 g / cm 3 The content of the polyethylene is preferably 10% by mass or more, and more preferably 20% by mass or more. 3 The content of the polyethylene is preferably 50% by mass or less, and more preferably 40% by mass or less, which allows for an appropriate seal strength to be obtained when the laminate is used as a lid material.

[0148] The polypropylene that is the main component of Layer A can be any of the polypropylenes described above. In one embodiment, the polypropylene that is the main component of Layer A has a density of 0.900 g / cm 3 More than 0.910g / cm 3 It is preferable to use a resin having a viscosity of 100 MPa or less and an MFR of 5 g / 10 min or more and 30 g / 10 min or less. From the viewpoint of obtaining an appropriate seal strength, the polypropylene, which is the main component of Layer A, is particularly preferably a propylene-ethylene random copolymer. An example of a suitable propylene-ethylene random copolymer is Novatec (registered trademark) FL02C manufactured by Japan Polypropylene Corporation. If the MFR is 5 g / 10 min or more, it is a low MFR polyethylene, i.e., a polyethylene having a density of 0.940 g / cm 3 The difference in fluidity with the polyethylene increases, resulting in a good dispersion state, and therefore, suitable easy-peel properties can be imparted. Furthermore, when the MFR is 30 g / 10 min or less, the fluidity of the polypropylene can be improved, and the film-forming properties of the easy-peel sealant layer can be improved. In the multi-layered easy peel sealant layer, the MFR is a value measured by Method A under conditions of a temperature of 190°C and a load of 21.18N in accordance with the method specified in JIS K7210-1:2014.

[0149] Density is 0.940g / cm 3 The MFR of the above polyethylene is preferably 0.1 g / 10 min or more, more preferably 0.5 g / 10 min or more. The density is 0.940 g / cm 3 The MFR of the above polyethylene is preferably 4 g / 10 min or less, and more preferably 3 g / 10 min or less.

[0150] Density is 0.940g / cm 3 The upper density limit for polyethylene is 0.965 g / cm 3 That is, the polyethylene may have a density of 0.940 g / cm 3 More than 0.965g / cm 3Resins having a density of less than 0.940 g / cm3 may also be used. 3 The above polyethylenes are obtained, for example, by polymerizing ethylene by a low-pressure polymerization method (gas phase polymerization using a Ziegler-Natta catalyst or liquid phase polymerization using a metallocene catalyst). Suitable polyethylenes include, for example, Hi-Zex (registered trademark) 3300F manufactured by Prime Polymer Co., Ltd. The density of polyethylene is a value measured according to the method specified in Method A of JIS K7112:1980 after annealing as specified in JIS K6760:1995.

[0151] The density of layer A is 0.900 g / cm 3 It is preferable that the concentration is 0.905 g / cm or more. 3 The density of Layer A is more preferably 0.950 g / cm or more. 3 It is preferable that the concentration is 0.925 g / cm or more. 3 More preferably, it is equal to or greater than this.

[0152] The thickness of Layer A is preferably 3 μm or more, more preferably 5 μm or more, and is preferably 30 μm or less, more preferably 20 μm or less, and even more preferably 10 μm or less.

[0153] Next, Layer B in the easy-peel sealant layer will be described.

[0154] In one embodiment, Layer B in the easy-peel sealant layer contains polypropylene as a main component (hereinafter also referred to as "Layer B1"). The polypropylene that is the main component of Layer B1 can be any of the polypropylenes described above. The polypropylene, which is the main component of layer B1, has a density of 0.900 g / cm 3 More than 0.910g / cm 3 It is preferable to use a resin having a MFR of 0.1 g / 10 min or more and 4 g / 10 min or less. In one embodiment, the polypropylene that is the main component of Layer B1 is particularly preferably a propylene-ethylene block copolymer, from the viewpoint of imparting appropriate easy-peel properties. Suitable propylene-ethylene block copolymers include, for example, PF380A manufactured by SunAllomer Co., Ltd. In one embodiment, the polypropylene that is the main component of the layer B1 is preferably a homopolymer from the viewpoint of recyclability. The phrase "containing polypropylene as a main component" means that Layer B1 contains more than 50% by mass of polypropylene.

[0155] In the layer B1, the polypropylene content is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 99% by mass or more.

[0156] The density of layer B1 is 0.880 g / cm 3 It is preferable that the concentration is 0.890 g / cm or more. 3 The density of the layer B1 is more preferably 0.920 g / cm or more. 3 It is preferable that the density is 0.910 g / cm or more. 3 More preferably, it is equal to or greater than this.

[0157] The thickness of Layer A is preferably thinner than the thickness of Layer B1. This improves adhesion to the layer located on the first base layer side and effectively suppresses stringiness of the easy-peel sealant layer. "Stringiness" refers to the resin remaining in a fibrous form on the seal peel surface when the laminate is used as a lid or the like. The thickness ratio of Layer A to Layer B1 (thickness of Layer A / thickness of Layer B1) is preferably 1 / 10 or more, more preferably 1 / 5 or more. The thickness ratio of Layer A to Layer B1 (thickness of Layer A / thickness of Layer B1) is preferably 1 / 1 or less, more preferably 1 / 2 or less.

[0158] In one embodiment, Layer B in the easy-peel sealant layer is a material having a density of 0.940 g / cm as a main component. 3 The layer B2 contains polyethylene having a density of 0.940 g / cm3 or more. 3 The polyethylene described in the layer A can be used for the above polyethylene. In addition, the density of the main component is 0.940 g / cm 3 "Contains polyethylene of 0.940 g / cm or more" means that layer B2 contains more than 50% by mass of polyethylene having a density of 0.940 g / cm or more. 3 This means that the polyethylene includes the above polyethylene.

[0159] In layer B2, the density is 0.940 g / cm 3 The content of the polyethylene is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 99% by mass or more.

[0160] The density of layer B2 is 0.930 g / cm 3 It is preferable that the concentration is 0.940 g / cm or more. 3 The density of layer B2 is more preferably 0.970 g / cm or more. 3 It is preferable that the density is 0.960 g / cm or more. 3 More preferably, it is equal to or greater than this.

[0161] The thickness of Layer A is preferably thinner than the thickness of Layer B2, which can improve adhesion to the layer located on the first base layer side and suitably suppress stringiness of the easy-peel sealant layer. The thickness ratio of Layer A to Layer B2 (thickness of Layer A / thickness of Layer B2) is preferably 1 / 20 or more, more preferably 1 / 15 or more. The thickness ratio of Layer A to Layer B2 (thickness of Layer A / thickness of Layer B2) is preferably 1 / 2 or less, more preferably 1 / 5 or less.

[0162] In the easy-peel sealant layer having a multi-layer structure, the layer B is preferably the layer B2 from the viewpoint of recyclability.

[0163] Layer B has a density of 0.940 g / cm within the range not impairing the object of the present invention. 3 Such polyethylene may include medium density polyethylene, low density polyethylene, and linear low density polyethylene. In Layer B, medium density polyethylene has a density of 0.930 g / cm 3 More than 0.940g / cm 3 Medium-density polyethylene is obtained, for example, by polymerizing ethylene using a low-pressure polymerization method. In Layer B, low density polyethylene has a density of 0.930 g / cm 3 less than 0.910 g / cm 3 More than 0.930g / cm 3 Low-density polyethylene is obtained by polymerizing only ethylene using a high-pressure polymerization method. In Layer B, the linear low-density polyethylene has a density of 0.930 g / cm 3 less than 0.910 g / cm 3 More than 0.930g / cm 3 Linear low-density polyethylene is obtained by polymerizing ethylene and a small amount of α-olefins using a low-pressure polymerization method.

[0164] The thickness of Layer B is preferably 15 μm or more, more preferably 20 μm or more, and is preferably 120 μm or less, more preferably 80 μm or less, and even more preferably 50 μm or less.

[0165] The polyethylene contained in the easy-peel sealant layer may be derived from fossil fuels, biomass, or a combination thereof.

[0166] The sealant layer may be formed by laminating a heat-sealable stretched or unstretched film with a conventionally known adhesive, or by applying and drying a heat-sealing agent.

[0167] (Adhesive layer) The adhesive layer contains at least one adhesive, and may be a one-component curing adhesive, a two-component curing adhesive, or a non-curing adhesive. The adhesive may be a solvent-free adhesive or a solvent-based adhesive, but from the viewpoint of environmental load, a solvent-free adhesive is preferably used. Examples of solvent-free adhesives include polyether adhesives, polyester adhesives, silicone adhesives, epoxy adhesives, and urethane adhesives, and among these, two-component curing urethane 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.

[0168] The thickness of the adhesive layer is not particularly limited, and can be, for example, 0.1 μm or more and 10 μm or less.

[0169] (Second base material) The second substrate serves to hold the layers together. The second substrate contains a resin material, such as polyolefin, vinyl resin, polyester, (meth)acrylic resin, or cellulose resin. Among these, polypropylene is particularly preferred from the viewpoint of the recyclability of the laminate.

[0170] The second substrate may contain additives similar to those described above, provided that the additives do not impair the properties of the present invention.

[0171] The second substrate may have the above-mentioned vapor-deposited film or barrier coat layer on its surface.

[0172] The second substrate is preferably a resin film made of the above resin material, and the resin film is preferably one that has been subjected to a stretching treatment. The stretching treatment may be uniaxial stretching or biaxial stretching.

[0173] In the embodiment in which the second substrate is provided, it is particularly preferable from the viewpoint of recyclability that the second substrate be formed from a stretched polypropylene resin film.

[0174] The thickness of the second substrate is preferably 10 μm or more, and more preferably 50 μm or less, and more preferably 40 μm or less. By setting the thickness of the second base material to 10 μm or more, the strength of the laminate can be further improved. Furthermore, by setting the thickness of the second base material to 50 μm or less, the processability of the laminate can be further improved.

[0175] The second substrate can be provided via the above-mentioned adhesive layer.

[0176] The second substrate may have a printed layer formed on its surface, and the method for forming the printed layer is as described above.

[0177] (middle class) In one embodiment, the laminate may have an intermediate layer between the vapor-deposited film and the sealant layer (or between the barrier coat layer and the sealant layer if a barrier coat layer is provided). The intermediate layer contains a resin material, such as polyolefin, vinyl resin, polyester, (meth)acrylic resin, or cellulose resin. Among these, polypropylene is particularly preferred from the viewpoint of the recyclability of the laminate.

[0178] The intermediate layer may contain the same additives as those described above, provided that the additives do not impair the properties of the present invention.

[0179] The intermediate layer may have the above-mentioned vapor-deposited film or barrier coat layer on its surface.

[0180] The intermediate layer is preferably made of a resin film made of the above resin material, and the resin film is preferably subjected to a stretching treatment.

[0181] In the embodiment having an intermediate layer, it is particularly preferred to use a stretched polypropylene resin film as the intermediate layer. When a stretched polypropylene resin film is used for the intermediate layer, the ease of tearing can be improved compared to when no stretched film is used. This is because when no stretched film is used for the intermediate layer, the film constituting the heat seal layer is unstretched and therefore flexible and easily stretched, which is thought to result in poor ease of tearing related to film residue when opening and difficulty in opening. Furthermore, wrinkles that may occur due to heat shrinkage during retort treatment, boiling treatment, or heating during heat sealing can be reduced, resulting in a good appearance. Furthermore, when the laminate is used as a lid material, wrinkles after heat sealing can be prevented, resulting in a good appearance.

[0182] The thickness of the intermediate layer is preferably 10 μm or more, and more preferably 50 μm or less, and more preferably 40 μm or less. By making the thickness of the intermediate layer 10 μm or more, the strength of the laminate can be further improved. Furthermore, by setting the thickness of the intermediate layer to 50 μm or less, the processability of the laminate can be further improved.

[0183] The intermediate layer can be provided via the above-mentioned adhesive layer.

[0184] The intermediate layer may have a printed layer formed on its surface, and the method for forming the printed layer is as described above.

[0185] In one embodiment, the intermediate layer may be a second substrate.

[0186] [Laminate in the second embodiment] As shown in FIG. 18, the laminate 10B of the present invention comprises a first substrate 11, a vapor-deposited film 12, and a sealant layer 13, and the first substrate 11 comprises at least a polypropylene resin layer 14 and a surface coating layer 15. In one embodiment of the present invention, the laminate 10 may further include a barrier coating layer 16 between the vapor-deposited film 12 and the sealant layer 13, as shown in FIG. In one embodiment of the present invention, the laminate may further include a second substrate. When the laminate includes a second substrate, the laminate 10 may include, in order, a second substrate 17, a vapor-deposited film 12, a first substrate 11, and a sealant layer 13, as shown in Fig. 20; or may include, in order, a second substrate 17, a first substrate 11, a vapor-deposited film 12, and a sealant layer 13, as shown in Fig. 21; or may include, in order, a first substrate 11, a vapor-deposited film 12, a second substrate 17, and a sealant layer 13, as shown in Fig. 22. The second substrate 17 in the laminates 10 of Figs. 20 and 21 and the first substrate 11 in the laminate 10 of Fig. 22 may be located as the outermost layer of the laminate 10. In one embodiment of the present invention, the laminate 10 may include an adhesive layer (not shown) between any of the vapor-deposited film, the sealant layer, the first substrate, and the second substrate. In other embodiments, the laminate of the present invention may include an intermediate layer between the vapor-deposited film and the sealant layer, and the intermediate layer may be the second substrate.

[0187] The haze value of the laminate is preferably 20% or less, and more preferably 5% or less, which can improve the transparency of the laminate.

[0188] In the laminate of the second aspect, the lamination strength between the first substrate and the vapor-deposited film is preferably 3 N or more, more preferably 4 N or more, and even more preferably 5.5 N or more, per 15 mm width. The upper limit of the lamination strength of the laminate of the second aspect may be 20 N or less. The method for measuring the lamination strength of the laminate will be explained in the examples below.

[0189] The tensile strength of the laminate in one direction may be 30 MPa or more, or 35 MPa or more. The tensile strength of the laminate in one direction may be 70 MPa or less, or 50 MPa or less. The one direction of the laminate may be the machine direction (MD). The tensile strength of the laminate in a direction perpendicular to the one direction may be 40 MPa or more, or 60 MPa or more. The tensile strength of the laminate in a direction perpendicular to the one direction may be 150 MPa or less, or 100 MPa or less. The direction perpendicular to the one direction may be the transverse direction (TD) of the laminate. In this specification, the tensile strength of the laminate is measured in accordance with JIS K7127: 1999. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Co., Ltd. can be used. The test specimens used are rectangular laminates cut from the laminate with a width of 10 mm and a length of 150 mm. The distance between the pair of chucks holding the test specimens at the start of the measurement is 50 mm, and the tensile speed is 300 mm / min. Unless otherwise specified, the environment during tensile strength measurement is a temperature of 23°C and a relative humidity of 50%.

[0190] The loop stiffness in one direction of the laminate may be 30 mN or more, 50 mN or more, or 70 mN or more. The loop stiffness in one direction of the laminate may be 200 mN or less, 150 mN or less, or 120 mN or less. The one direction of the laminate may be the machine direction (MD). The loop stiffness of the laminate in a direction perpendicular to the one direction may be 30 mN or more, 50 mN or more, or 70 mN or more. The loop stiffness of the laminate in a direction perpendicular to the one direction may be 200 mN or less, 150 mN or less, or 130 mN or less. The direction perpendicular to the one direction may be the transverse direction (TD) of the laminate. The method for measuring the loop stiffness is as explained in the first embodiment.

[0191] The piercing strength of the laminate may be 10 N or more, or 15 N or more. The puncture strength of the laminate is measured in accordance with JIS Z1707 7.4, and the specific measurement method will be explained in the examples below.

[0192] As in the first embodiment, the sealant layer is preferably made of the same material as the polypropylene resin layer of the first substrate, i.e., polypropylene, which can improve the recyclability of packaging containers made using the laminate of the present invention.

[0193] When the sealant layer is made of polypropylene, the content of polypropylene relative to the total amount of resin materials contained in the laminate of the present invention is preferably 80% by mass or more, more preferably 95% by mass or more, thereby further improving the recyclability of packaging containers produced using the laminate of the present invention.

[0194] The laminate according to the second aspect of the present invention will be described below, but the layers other than the surface coating layer constituting the first substrate are the same as those in the laminate according to the first aspect described above, and therefore will not be described here.

[0195] (surface coating layer) The first substrate has a surface coating layer containing a resin material having a polar group on a polypropylene resin layer, which allows a vapor-deposited film with high adhesion to be formed on the surface coating layer, improving gas barrier properties. Furthermore, as will be described later, packaging containers produced using a laminate having the surface coating layer have high laminate strength. In one embodiment, the surface coating layer may be provided on the polypropylene resin layer, i.e., the surface coating layer may be adjacent to the polypropylene resin layer.

[0196] The surface coating layer contains a resin material having a polar group. In the present invention, the polar group refers to a group containing one or more heteroatoms. Examples of the polar group include an ester group, an epoxy group, a hydroxyl group, an amino group, an amide group, a carboxyl group, a carbonyl group, a carboxylic anhydride group, a sulfone group, a thiol group, and a halogen group. Among these, from the viewpoint of lamination properties of the packaging container, a carboxyl group, a carbonyl group, an ester group, a hydroxyl group, and an amino group are preferred, and a carboxyl group and a hydroxyl group are more preferred.

[0197] As the resin material having a polar group, polyester, polyethyleneimine, hydroxyl group-containing (meth)acrylic resin, polyamide such as nylon 6, nylon 6,6, MXD nylon, amorphous nylon, polyurethane, etc. are preferred. By using such a resin material, the adhesion of the vapor-deposited film formed on the surface coating layer can be significantly improved, and the gas barrier properties thereof can be effectively improved.

[0198] In one embodiment, the resin material having a polar group is preferably a hydroxyl group-containing (meth)acrylic resin, which can improve the heat resistance of the laminate and can prevent deterioration of the gas barrier properties even after the laminate is subjected to retort treatment and boiling treatment.

[0199] In one embodiment of the present invention, the hydroxyl group-containing (meth)acrylic resin used to form the surface coating layer is a polymer of a neutral monomer and a hydroxyl group-containing (meth)acrylic monomer. Examples of neutral monomers include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, styrene, vinyl toluene, and vinyl acetate. Examples of the hydroxyl group-containing (meth)acrylic monomer include 2-hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate.

[0200] The glass transition temperature (Tg) of the hydroxyl group-containing (meth)acrylic resin is preferably 50° C. or higher, more preferably 70° C. or higher. The glass transition temperature (Tg) of the hydroxyl group-containing (meth)acrylic resin is preferably 200° C. or lower, more preferably 150° C. or lower. By adjusting the glass transition temperature (Tg) of the hydroxyl group-containing (meth)acrylic resin to 50° C. or higher, blocking resistance can be improved. By setting the glass transition temperature (Tg) of the hydroxyl group-containing (meth)acrylic resin to 200°C or less, the reactivity of an isocyanate compound can be improved when the hydroxyl group-containing (meth)acrylic resin is used together with an isocyanate compound to form a surface coating layer. In this specification, Tg can be measured in accordance with JIS K7121:2012 (Method for measuring transition temperature of plastics). Specifically, Tg can be determined by measuring a DSC curve at a temperature rise rate of 10°C / min using a differential scanning calorimetry (DSC) device.

[0201] The number average molecular weight of the hydroxyl group-containing (meth)acrylic resin is preferably 10,000 or more, and the number average molecular weight of the hydroxyl group-containing (meth)acrylic resin is preferably 100,000 or less. By adjusting the number average molecular weight of the hydroxyl group-containing (meth)acrylic resin to 10,000 or more, blocking resistance can be improved. By adjusting the number average molecular weight of the hydroxyl group-containing (meth)acrylic resin to 100,000 or more, the ease of forming the surface coating layer can be improved. In this specification, the number average molecular weight can be measured by gel permeation chromatography (GPC). In GPC measurement, the number average molecular weight of a polymer is generally measured in terms of standard polystyrene.

[0202] The hydroxyl value of the hydroxyl group-containing (meth)acrylic resin is preferably 20 mg KOHL / g or more, more preferably 30 mg KOHL / g or more, and preferably 200 mg KOHL / g or less, more preferably 150 mg KOHL / g or less. By making the hydroxyl value of the hydroxyl group-containing (meth)acrylic resin 20 mg KOHL / g or more, the reactivity of an isocyanate compound can be improved when the hydroxyl group-containing (meth)acrylic resin is used together with the isocyanate compound to form the surface coating layer. By setting the hydroxyl value of the hydroxyl group-containing (meth)acrylic resin to 200 mg KOHL / g or less, the amount of isocyanate compound used can be reduced, thereby reducing production costs. In this specification, the hydroxylation can be measured in accordance with JIS K0070:1992 (Test methods for oxidation, saponification value, ester value, iodine value, hydroxyl value and unsaponifiable matter of chemical products).

[0203] 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-based emulsions, polyethylene-based emulsions, and polyurethane-based emulsions. Specific examples of solvent-based emulsions include polyester-based emulsions.

[0204] The content of the resin material having a polar group 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.

[0205] The surface coating layer may contain a resin material other than the resin material having a polar group, as long as the characteristics of the present invention are not impaired. In one embodiment of the present invention, the surface coating layer may contain an isocyanate compound. The surface coating layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins, as long as the additives do not impair the properties of the present invention.

[0206] The ratio of the thickness of the surface coating layer to the total thickness of the first substrate is preferably 0.08% or more, more preferably 0.2% or more, even more preferably 1% or more, and even more preferably 3% or more. The ratio of the thickness of the surface coating layer to the total thickness of the first substrate is preferably 20% or less, and more preferably 10% or less. By setting the ratio of the thickness of the surface coating layer to the total thickness of the first substrate to be 0.08% or more, the adhesion of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. By setting the ratio of the thickness of the surface coating layer to the total thickness of the first substrate to 20% or less, the film-forming property and processability of the first substrate can be further improved. Furthermore, as will be described later, the recyclability of packaging containers produced using a laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0207] The thickness of the surface coating layer is preferably 0.02 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, and even more preferably 0.2 μm or more. The thickness of the surface coating layer is preferably 10 μm or less, and more preferably 5 μm or less. By making the thickness of the surface coating layer 0.02 μm or more, the adhesion of the vapor-deposited film can be further improved, the gas barrier properties can be further improved, and the laminate strength of the packaging container can be further improved. By setting the thickness of the surface coating layer to 10 μm or less, the film-forming property and processability of the first substrate can be further improved, and as will be described later, the recyclability of packaging containers produced using a laminate of the laminate of the present invention and a sealant layer made of polypropylene can be improved.

[0208] The first substrate can be produced offline. Specifically, a resin composition containing polypropylene is formed into a film using a T-die method, an inflation method, or the like, and then stretched to form a resin film. A coating liquid for forming a coat is applied onto the resin film, followed by drying. The first substrate can be produced in-line. Specifically, a resin composition containing polypropylene is formed into a film using a T-die method or an inflation method, and then stretched in the machine direction (MD). A coating liquid for forming a coat is applied to the resin film, dried, and then stretched in the transverse direction (TD). The stretching in the transverse direction may be performed first. Stretching in both the machine direction and the transverse direction may be performed before or after applying the coating liquid for forming a coat.

[0209] [Lid material] The laminate described above can be suitably used as a packaging material, particularly as a lid material. The lid material of the present invention will be described with reference to the drawings.

[0210] 23 and 24 show a packaging container 62 having a lid material 60 and a container body 61, where the lid material 60 is made of the above-mentioned laminate. Because the lid material 60 is made of the above-mentioned laminate, it has excellent gas barrier properties and suitability for retort treatment and boiling treatment, despite being a mono-material packaging material.

[0211] The container body 61 includes a storage portion 63 and a flange 64 . In one embodiment, the storage section 63 has a cylindrical shape with a bottom and a circular opening 65 on the upper surface, and stores contents 66. The flange 64 is formed as a substantially flat surface extending from the outer periphery of the opening 65 in the outer periphery direction.

[0212] The container body 61 can be made of, for example, polyethylene, polypropylene, polyethylene terephthalate, etc. The container body 61 may also be made of a hard paper material.

[0213] The laminate constituting the lid member 60 is placed on top of the flange 64 of the container body 61 so that the sealant layer is in contact with the flange 64, and then heat-sealed. As a result, the opening 65 is sealed by the lid member 60. In one embodiment, the lid member 60 may be provided with a gripping portion 67 that protrudes from the flange 64 toward the outer periphery.

[0214] Heat sealing can be performed by any known method, such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, or ultrasonic sealing.

[0215] The contents filled in the packaging container are not particularly limited and may be liquid, powder, or gel. The contents may be food or non-food. [Example]

[0216] 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.

[0217] Example 1 Polyamide (Ube Industries, Ltd., Polyamide 6, melting point: 220 ° C), adhesive resin (Mitsui Chemicals, Inc., Admer QF500, maleic anhydride-modified polypropylene), and polypropylene (Japan Polypropylene, Novatec FL203D, melting point: 160 ° C) were coextruded from a T-die to form five layers of polyamide / adhesive resin / polypropylene / polypropylene / polypropylene in a thickness ratio of 1 / 13 / 24 / 6 / 2. The resulting layer was then stretched 5 times in the machine direction (MD) and 10 times in the transverse direction (TD) using a sequential biaxial stretching device to produce a 20 μm thick substrate. The ratio of the thickness of the polyamide surface resin layer to the substrate layer thickness was approximately 2%.

[0218] On the surface resin layer of the substrate prepared as described above, a carbon-containing silicon oxide vapor deposition film with a thickness of 12 nm was formed (CVD method) using a low-temperature plasma chemical vapor deposition apparatus (actual equipment) in a roll-to-roll manner while applying tension to the substrate. The vapor deposition film formation conditions were as follows: (Formation conditions) Hexamethyldisiloxane: oxygen gas: helium = 1:10:10 (unit: slm) Cooling and electrode drum power supply: 22kw Line speed: 100m / min

[0219] In the carbon-containing silicon oxide vapor-deposited film, the carbon percentage C, silicon percentage Si, and oxygen percentage O were 32.7%, 29.8%, and 37.5%, respectively, based on a total of 100% for the three elements silicon, oxygen, and carbon. The percentages 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] Spectral collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): approx. 6 mm diameter Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching range: 10mmφ Ion sputtering time: 30 seconds, and the spectrum was collected.

[0220] Next, a barrier coating agent was spin-coated onto the vapor-deposited film formed on the substrate, and the resulting film was heated in an oven at 80°C for 60 seconds to form a barrier coating layer with a thickness of 300 nm. The barrier coating agent used was prepared as follows:

[0221] 385 g of water, 67 g of isopropyl alcohol, and 9.1 g of 0.5 N hydrochloric acid were mixed to obtain a solution with a pH of 2.2. 175 g of tetraethoxysilane as a metal alkoxide and 9.2 g of glycidoxypropyltrimethoxysilane as a silane coupling agent were mixed with this solution while cooling to 10°C, to obtain solution A. Solution B was obtained by mixing 14.7 g of polyvinyl alcohol as a water-soluble polymer having a saponification degree of 99% or more and a polymerization degree of 2400, 324 g of water, and 17 g of isopropyl alcohol. Solution A and solution B were mixed in a mass ratio of 6.5:3.5 to obtain a barrier coating agent.

[0222] On the surface of the barrier coating layer formed as described above, a coating amount of 4.0 / m was applied by dry lamination. 2 A two-component curing polyester urethane adhesive (Lockbond J RU004 / H1 (mixing ratio 7 / 1) manufactured by Rock Paint) was applied to form an adhesive layer, and then a 50 μm thick easy-peel CPP for retort use (CF Film 9501H manufactured by Toray Advanced Film Co., Ltd.) was laminated on the adhesive layer to form a heat-seal layer, and the laminate was further cured at 40°C for 5 days to obtain a laminate of the present invention. The polypropylene content of the resulting laminate was 88% by mass. CF Film 9501H is an unstretched polypropylene film with a multilayer structure including Layer A and Layer B. Layer A is thinner than Layer B. Layer A contains a propylene-ethylene copolymer and polyethylene, and contains 90% or more by mass of a polypropylene homopolymer.

[0223] Example 2 A 20 μm thick biaxially oriented polypropylene film (ME-1, manufactured by Mitsui Chemicals Tohcello Co., Ltd.), one side of which had been corona treated, was coated with a solution for forming a surface coating layer having the following composition and dried to form a 0.5 μm thick surface coating layer, thereby preparing a substrate.

[0224] (Preparation of solution for forming surface coating layer) 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) to a solids concentration of 10 mass % to prepare the base resin. An ethyl acetate solution containing tolylene diisocyanate (solid content 75% by mass) was added to the base resin as a curing agent to obtain a solution for forming a surface coating layer. The amount of the curing agent used was 10 parts by mass per 100 parts by mass of the base resin.

[0225] On the surface coating layer of the substrate prepared as described above, a carbon-containing silicon oxide vapor deposition film with a thickness of 12 nm was formed (CVD method) using a low-temperature plasma chemical vapor deposition apparatus, which is an actual device, by roll-to-roll while applying tension to the substrate. The vapor deposition film formation conditions were as follows: (Formation conditions) Hexamethyldisiloxane: oxygen gas: helium = 1:10:10 (unit: slm) Cooling and electrode drum power supply: 22kw Line speed: 100m / min

[0226] The carbon percentage C, silicon percentage Si, and oxygen percentage O in the carbon-containing silicon oxide vapor-deposited film were measured in the same manner as in Example 1. The carbon percentage C, silicon percentage Si, and oxygen percentage O were 32.7%, 29.8%, and 37.5%, respectively, relative to the total of the three elements silicon, oxygen, and carbon, which was 100%.

[0227] 385 g of water, 67 g of isopropyl alcohol, and 9.1 g of 0.5 N hydrochloric acid were mixed to obtain a solution with a pH of 2.2. 175 g of tetraethoxysilane as a metal alkoxide and 9.2 g of glycidoxypropyltrimethoxysilane as a silane coupling agent were mixed with this solution while cooling to 10°C, to obtain solution A. Solution B was obtained by mixing 14.7 g of polyvinyl alcohol as a water-soluble polymer having a saponification degree of 99% or more and a polymerization degree of 2400, 324 g of water, and 17 g of isopropyl alcohol. Solution A and solution B were mixed in a mass ratio of 6.5:3.5 to obtain a barrier coating agent.

[0228] The deposited film formed on the substrate was coated with a barrier coating agent by spin coating, and then heated in an oven at 80° C. for 60 seconds to form a barrier coating layer with a thickness of 300 nm.

[0229] A sealant layer was formed on the surface of the barrier coat layer formed as described above in the same manner as in Example 1, thereby obtaining a laminate of the present invention. The polypropylene content in the laminate was 89% by mass.

[0230] Comparative Example 1 The above polypropylene (Novatec FL203D, manufactured by Japan Polypropylene Corporation, melting point: 160°C) was extruded and then stretched 5 times in the machine direction (MD direction) and 10 times in the transverse direction (TD direction) using a sequential biaxial stretching device to produce a propylene film with a thickness of 20 μm. A laminate was produced in the same manner as in Example 1, except that the substrate in Example 1 was changed to the polypropylene film produced as described above. The polypropylene content in the laminate was 90 mass %.

[0231] <Gas barrier property evaluation> The laminates obtained in the above Examples and Comparative Examples were cut out to obtain test pieces. The test pieces were used to measure the oxygen permeability (cc / m 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured by the following method. The measurement results are shown in Table 1.

[0232] [Oxygen permeability] Using an oxygen permeability measuring device (OX-TRAN2 / 20 manufactured by MOCON), the test piece was set so that the substrate side was the oxygen supply side, and the oxygen permeability was measured in an environment of 23°C and a relative humidity of 90% RH in accordance with JIS K 7126.

[0233] [Water vapor permeability] Using a water vapor permeability measuring device (MOCON, PERMATRAN-w 3 / 33), the test piece was set so that the substrate side was the water vapor supply side, and the water vapor permeability was measured in an environment of 40°C and relative humidity 90% RH in accordance with JIS K 7129.

[0234] <Laminate strength test> The laminates obtained in the above Examples and Comparative Examples were cut into 15 mm wide strips, and the laminate strength (N / 15 mm) of each sample was measured using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K6854-2, at a peel rate of 50 mm / min and a 90° peel angle (T-peel method). Specifically, first, a laminate was cut out, and a strip-shaped test piece 70 was prepared by peeling the substrate side 71 and the sealant layer side 72 by 15 mm in the long side direction, as shown in FIG. 25 . Then, as shown in FIG. 26 , the already peeled portions of the substrate side 71 and the sealant layer side 72 were each gripped with a measuring device grip 73. The grips 73 were pulled at a speed of 50 mm / min in opposite directions perpendicular to the plane of the portions where the substrate side 71 and the sealant layer side 72 were still laminated, and the average value of tensile stress in the stable region (see FIG. 27 ) was measured. The spacing S between the grips 73 at the start of pulling was 30 mm, and the spacing S between the grips 73 at the end of pulling was 60 mm. FIG. 27 shows the change in tensile stress with respect to the spacing S between the grips 73. As shown in FIG. 27 , the change in tensile stress with respect to the spacing S passes through a first region and then enters a second region (stable region) where the rate of change is smaller than that in the first region. The average value of the tensile stress in the stable region was measured for five test pieces 70, and the average value was used as the laminate strength. The measurement was performed in an environment of a temperature of 23°C and a relative humidity of 50%. The measurement results are summarized in Table 1.

[0235] <<Gas barrier property evaluation after retort processing>> [Oxygen permeability] The laminates obtained in the above Examples and Comparative Examples were used as lids for cup-shaped polypropylene containers (capacity 120 cc) by sealing at a sealing temperature of 200°C from flat sealing to 1 kg / cm 2 The cup was sealed under the condition of 1 second, 2 seconds, and 3 seconds, and a cup-shaped container filled with water was prepared as shown in FIG.

[0236] The cup-shaped container was subjected to a retort treatment at 121°C for 30 minutes under 2 atmospheres. After the retort treatment, the lid was removed from the container body to prepare a test specimen.

[0237] Using an oxygen permeability measuring device (MOCON, OX-TRAN10 / 50A), the test piece was set so that the substrate side was the oxygen supply side, and the oxygen permeability was measured in an environment of 30°C and a relative humidity of 70% RH in accordance with JIS K 7126. The measurement results are shown in Table 1.

[0238] [Water vapor permeability] The water vapor permeability of the test piece was measured using a water vapor permeability measuring device (PERMATRAN-w 3 / 33, manufactured by MOCON) in an environment of 40°C and a relative humidity of 90%RH in accordance with JIS K 7129, with the test piece being set so that the substrate side was the water vapor supply side. The measurement results are shown in Table 1.

[0239] <<Laminate strength after retort treatment>> After retort treatment, the lid was peeled off from the container body and cut into 15 mm wide strips to obtain test specimens. The laminate strength (N / 15 mm) of the test specimens was measured in accordance with JIS K6854-2 using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) at a peel rate of 50 mm / min and a 90° peel angle (T-peel method). The measurement results are shown in Table 1.

[0240] [Table 1]

[0241] Example 3-1 In the same manner as in Example 1, a substrate was prepared and a vapor-deposited film was formed on the substrate.

[0242] A barrier coat layer was formed on the vapor-deposited film so that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 5.1 on a mass basis.

[0243] The ratio of Si element to C element present on the surface of the barrier coat layer was measured. The measurement was performed by narrow scan analysis using X-ray photoelectron spectroscopy (XPS) under the following measurement conditions. In the following examples, the ratio of Si element to C element present on the surface of the barrier coat layer was measured in the same manner. (Measurement conditions) Equipment used: "ESCA-3400" (manufactured by Kratos) [1] Spectral collection conditions Incident X-ray: MgKα (monochromatic X-ray, hν=1253.6eV) X-ray output: 150W (10kV 15mA) X-ray scanning area (measurement area): approx. 6 mm diameter Photoelectron capture angle: 90 degrees [2] Ion sputtering conditions Ion species: Ar + Acceleration voltage: 0.2 (kV) Emission current: 20 (mA) Etching range: 10mmφ Ion sputtering time: 30 seconds + 30 seconds + 60 seconds (total 120 seconds) and spectrum was collected.

[0244] Next, a 50 μm thick unstretched polypropylene film (EP-7R, manufactured by Dai Nippon Printing Co., Ltd.) with easy peel properties was dry laminated onto the barrier coat layer using a two-component curing polyurethane adhesive to form a sealant layer, thereby obtaining a laminate in the first embodiment. EP-7R is an unstretched polypropylene film having a multilayer structure including Layer A and Layer B. Layer A is a 70% by mass propylene-ethylene random copolymer (density 0.900 g / cm 3 , MFR 18.0 g / 10 min) and 30 mass% high-density polyethylene (density 0.950 g / cm 3 Layer B is a propylene-ethylene block copolymer (density 0.900 g / cm 3 The thickness of Layer A is 10 μm, and the thickness of Layer B is 40 μm.

[0245] Example 3-2 A laminate in the first embodiment was produced in the same manner as in Example 3-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0246] Example 3-3 A laminate in the first embodiment was produced in the same manner as in Example 3-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0247] Examples 3-4 A laminate in the first embodiment was produced in the same manner as in Example 3-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0248] Examples 3-5 A laminate in the first embodiment was produced in the same manner as in Example 3-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0249] Examples 3-6 A laminate according to the first embodiment was produced in the same manner as in Example 3-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0250] Example 4-1 A laminate according to the first embodiment was produced in the same manner as in Example 3-1, except that the formation of the vapor-deposited film was changed as follows. Using a continuous vapor deposition film formation device that has a pretreatment section in which an actual oxygen plasma pretreatment device is placed and a film formation section separated from each other, in the pretreatment section, tension is applied to the multilayer substrate by roll-to-roll movement, and plasma is introduced from a plasma supply nozzle under the conditions described below to perform oxygen plasma pretreatment. In the film formation section, which is continuously transported, a 12 nm thick aluminum oxide (alumina) vapor deposition film is formed on the oxygen plasma-treated surface under the conditions described below using a reactive resistance heating method as the heating means for vacuum vapor 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 pretreatment drum and plasma supply nozzle: 340V (Film formation conditions) Conveying speed: 400m / min Oxygen gas supply: 20,000 sccm

[0251] Example 4-2 A laminate in the first embodiment was produced in the same manner as in Example 4-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0252] Example 4-3 A laminate in the first embodiment was produced in the same manner as in Example 4-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0253] Example 4-4 A laminate in the first embodiment was produced in the same manner as in Example 4-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0254] Examples 4-5 A laminate in the first embodiment was produced in the same manner as in Example 4-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0255] Examples 4-6 A laminate in the first embodiment was produced in the same manner as in Example 4-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0256] Example 5-1 In the same manner as in Example 2, a substrate was prepared and a vapor-deposited film was formed on the substrate.

[0257] Next, a barrier coat layer was formed on the vapor-deposited film so that the solid content ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 5.1 on a mass basis.

[0258] Next, a 50 μm thick unstretched polypropylene film (EP-7R, manufactured by Dai Nippon Printing Co., Ltd.) with easy peel properties was dry laminated onto the barrier coat layer using a two-component curing polyurethane adhesive to form a sealant layer, thereby obtaining a laminate in the second embodiment.

[0259] Example 5-2 A laminate of the second embodiment was produced in the same manner as in Example 5-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0260] Example 5-3 A laminate of the second embodiment was produced in the same manner as in Example 5-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0261] Example 5-4 A laminate of the second embodiment was produced in the same manner as in Example 5-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0262] Example 5-5 A laminate of the second embodiment was produced in the same manner as in Example 5-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0263] Examples 5-6 A laminate of the second embodiment was produced in the same manner as in Example 5-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0264] Example 6-1 A third laminate was produced in the same manner as in Example 5-1, except that the deposition film was formed as follows. A silicon oxide (silica) vapor deposition film with a thickness of 20 nm was formed on the surface coating layer using an induction heating vacuum deposition device equipped with a plasma gun, using a roll-to-roll method while applying tension to the multilayer substrate (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 formation conditions) Deposition material: SiO Reactive gas: O2 Reaction gas flow rate: 100sccm

[0265] Example 6-2 A laminate of the second embodiment was produced in the same manner as in Example 6-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0266] Example 6-3 A laminate of the second embodiment was produced in the same manner as in Example 6-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0267] Example 6-4 A laminate of the second embodiment was prepared in the same manner as in Example 6-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0268] Examples 6-5 A laminate of the second embodiment was produced in the same manner as in Example 6-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0269] Example 6-6 A laminate of the second embodiment was produced in the same manner as in Example 6-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0270] Example 7-1 A laminate according to the second embodiment was produced in the same manner as in Example 5-1, except that the formation of the vapor-deposited film was changed as follows.

[0271] Using a continuous vapor deposition film formation device that has a pretreatment section in which an actual oxygen plasma pretreatment device is placed and a film formation section separated from each other, in the pretreatment section, tension is applied to the multilayer substrate by roll-to-roll movement, and plasma is introduced from a plasma supply nozzle under the conditions described below to perform oxygen plasma pretreatment on the surface coating layer. In the film formation section, which is continuously transported, a 12 nm thick aluminum oxide (alumina) vapor deposition film is formed on the oxygen plasma treated surface under the conditions described below using a reactive resistance heating method as the heating means for vacuum vapor 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 pretreatment drum and plasma supply nozzle: 340V (Film formation conditions) Conveying speed: 400m / min Oxygen gas supply: 20,000 sccm

[0272] Example 7-2 A laminate of the second embodiment was produced in the same manner as in Example 7-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 4.1 by mass.

[0273] Example 7-3 A laminate of the second embodiment was prepared in the same manner as in Example 7-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 3.3 by mass.

[0274] Example 7-4 A laminate of the second embodiment was prepared in the same manner as in Example 7-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 2.7 by mass.

[0275] Example 7-5 A laminate of the second embodiment was prepared in the same manner as in Example 7-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.9 by mass.

[0276] Examples 7-6 A laminate of the second embodiment was prepared in the same manner as in Example 7-1, except that the barrier coat layer was formed so that the solids ratio of the metal alkoxide to the water-soluble polymer (metal alkoxide / water-soluble polymer) was 1.5 by mass.

[0277] <<Gas barrier property evaluation after lamination>> The laminates obtained in Examples 3 to 7 were cut out to obtain test pieces. Using these test pieces, the oxygen permeability (cc / m 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured. The results are summarized in Tables 2 to 6. In Tables 2 to 6, the units for oxygen permeability and water vapor permeability are omitted.

[0278] <<Gas barrier property evaluation after boiling treatment>> The laminates obtained in Examples 3 to 7 were used as lids for cup-shaped polypropylene containers (capacity 120 cc) and were subjected to a flat seal to seal temperature of 200°C and 1 kg / cm 2 The cup was sealed under the condition of 1 second, 2 seconds, and 3 seconds, and a cup-shaped container filled with water was prepared as shown in FIG. The cup-shaped container was subjected to a boiling treatment at 95°C for 30 minutes. After the retort treatment, the lid was removed from the container body to prepare a test specimen. Using this test piece, the oxygen permeability (cc / m 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured. The results are summarized in Tables 2 to 6. In Tables 2 to 6, the units for oxygen permeability and water vapor permeability are omitted.

[0279] <<Gas barrier property evaluation after retort processing>> The laminates obtained in Examples 3 to 7 were used as lids for cup-shaped polypropylene containers (capacity 120 cc) and were subjected to a flat seal to seal temperature of 200°C and 1 kg / cm 2 The cup was sealed under the condition of 1 second, 2 seconds, and 3 seconds, and a cup-shaped container filled with water was prepared as shown in FIG. The cup-shaped container was subjected to a retort treatment at 121°C for 30 minutes under 2 atmospheres. After the retort treatment, the lid was removed from the container body to prepare a test specimen. Using this test piece, the oxygen permeability (cc / m 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured. The results are summarized in Tables 2 to 6. In Tables 2 to 6, the units for oxygen permeability and water vapor permeability are omitted.

[0280] <<Gas barrier property evaluation after Gelbo Flex test>> Cylindrical bags were produced using the laminates obtained in Examples 3 to 7. Using these bags, the Gelbo Flex test in accordance with ASTM F392 was repeated 10 times. Thereafter, the laminate was cut out from the bag to obtain a test piece. The test piece was used to measure the oxygen permeability (cc / m 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured. The results are summarized in Tables 2 to 6. In Tables 2 to 6, the units for oxygen permeability and water vapor permeability are omitted.

[0281] [Table 2]

[0282] [Table 3]

[0283] [Table 4]

[0284] [Table 5]

[0285] [Table 6]

[0286] Example 8-1 In the same manner as in Example 1, a substrate was prepared, a vapor-deposited film was formed on the surface resin layer, and a barrier coat layer was formed on the vapor-deposited film.

[0287] Next, a printing layer was formed on the barrier coating layer, and the thickness of the printing layer was 1 μm.

[0288] Next, a 50 μm thick easy-peel CPP for retort applications (CF Film 9501H, manufactured by Toray Advanced Film Co., Ltd.) was dry-laminated onto the printed layer as a sealant layer via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1), manufactured by Mitsui Chemicals, Inc.), and left to stand at 40°C for 24 hours to obtain a laminate. The thickness of the adhesive layer was 4 μm. The obtained laminate comprised, in this order, a substrate, a vapor-deposited film, a barrier coat layer, a printed layer, an adhesive layer, and a sealant layer. The total thickness of the laminate was 75 μm, and the polypropylene content in the laminate was 88 mass %.

[0289] Example 8-2 In the same manner as in Example 1, a substrate was prepared, a vapor-deposited film was formed on the surface resin layer, and a barrier coat layer was formed on the vapor-deposited film.

[0290] Separately, a biaxially oriented polypropylene resin film having a thickness of 20 μm was prepared. A printed layer was formed on the biaxially oriented polypropylene resin film. The printed layer had a thickness of 1 μm. Next, the barrier coat layer of the above substrate was dry laminated onto the printed layer via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1) manufactured by Mitsui Chemicals, Inc.), and left to stand at 40°C for 24 hours to obtain a pre-laminate.

[0291] Next, a 50 μm thick easy-peel CPP for retort applications (CF Film 9501H, manufactured by Toray Advanced Film Co., Ltd.) was dry-laminated onto the biaxially oriented polypropylene resin film of the pre-laminate via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1), manufactured by Mitsui Chemicals, Inc.), and left to stand at 40°C for 24 hours to obtain a laminate. The adhesive layer had a thickness of 4 μm. The obtained laminate comprised, in this order, a first substrate, a vapor-deposited film, a barrier coat layer, an adhesive layer, a printed layer, a second substrate, an adhesive layer, and a sealant layer. The total thickness of the laminate was 99 μm, and the polypropylene content in the laminate was 85% by mass.

[0292] Example 9-1 In the same manner as in Example 2, a substrate was prepared, a vapor-deposited film was formed on the surface coating layer, and a barrier coating layer was formed on the vapor-deposited film.

[0293] Next, a printing layer was formed on the barrier coating layer, and the thickness of the printing layer was 1 μm.

[0294] Next, a 50 μm thick easy-peel CPP for retort applications (CF Film 9501H, manufactured by Toray Advanced Film Co., Ltd.) was dry-laminated onto the printed layer as a sealant layer via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1), manufactured by Mitsui Chemicals, Inc.), and left to stand at 40°C for 24 hours to obtain a laminate. The thickness of the adhesive layer was 4 μm. The obtained laminate comprised, in this order, a substrate, a vapor-deposited film, a barrier coat layer, a printed layer, an adhesive layer, and a sealant layer. The total thickness of the laminate was 75 μm, and the polypropylene content in the laminate was 88 mass %.

[0295] Example 9-2 In the same manner as in Example 2, a substrate was prepared, a vapor-deposited film was formed on the surface coating layer, and a barrier coating layer was formed on the vapor-deposited film.

[0296] Separately, a biaxially oriented polypropylene resin film having a thickness of 20 μm was prepared. A printed layer was formed on the biaxially oriented polypropylene resin film. The printed layer had a thickness of 1 μm. Next, the barrier coat layer of the above substrate was dry laminated onto the printed layer via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1) manufactured by Mitsui Chemicals, Inc.), and left to stand at 40°C for 24 hours to obtain a pre-laminate.

[0297] Next, a 50 μm thick easy-peel CPP for retort applications (CF Film 9501H, manufactured by Toray Advanced Film Co., Ltd.) was dry-laminated onto the biaxially oriented polypropylene resin film of the pre-laminate via a polyurethane adhesive (Takelac A-969V / Takenate A-5 (mixing ratio 3 / 1), manufactured by Mitsui Chemicals, Inc.) and left to stand at 40°C for 24 hours to obtain a laminate in the second embodiment. The thickness of the adhesive layer was 4 μm. The obtained laminate comprised, in this order, a first substrate, a vapor-deposited film, a barrier coat layer, an adhesive layer, a printed layer, a second substrate, an adhesive layer, and a sealant layer. The total thickness of the laminate was 99 μm, and the polypropylene content in the laminate was 85% by mass.

[0298] <<Tensile strength measurement>> The tensile strength of the laminates prepared in the above Reference Examples was measured in the machine direction (MD) and transverse direction (TD). The tensile strength of the laminates was measured in accordance with JIS K7127:1999. The tensile tester used was an Orientec STA-1150 tensile tester. A rectangular film 10 mm wide and 150 mm long cut from the laminate can be used as a test piece. The distance between the pair of chucks holding the test piece at the start of the measurement was 50 mm, and the tensile speed was 300 mm / min. The measurement was performed in an environment with a temperature of 23°C and a relative humidity of 50%. The measurement results are summarized in Table 7.

[0299] <<Loop stiffness measurement>> The loop stiffness of the laminate of the above-mentioned Reference Example was measured. The specific measurement method was as explained with reference to Figures 8 to 14. The measurement results are summarized in Table 7.

[0300] <<Measurement of puncture strength>> The puncture strength of the laminate of the reference example was measured in accordance with JIS Z1707 7.4. The measuring instrument used was a Tensilon universal material testing machine RTC-1310 manufactured by A&D. Specifically, as shown in FIG. 28, a semicircular needle 111 with a diameter of 1.0 mm and a tip radius of 0.5 mm was pierced into a fixed test piece 110 at a speed of 50 mm / min (50 mm per minute), and the maximum stress until the needle 111 penetrated the test piece 110 was measured. The maximum stress was measured for five or more test pieces 111, and the average value was used as the puncture strength of the laminate. The measurement was performed in an environment of 23°C and 50% relative humidity. The measurement results are summarized in Table 7.

[0301] [Table 7] [Explanation of symbols]

[0302] 10A: laminate, 11A: first substrate, 12A: vapor deposition film, 13A: sealant layer, 14A: polypropylene resin layer, 15A: surface resin layer, 16A: barrier coat layer, 17A: adhesive resin layer, 10B: laminate, 11B: first substrate, 12B: vapor deposition film, 13B: sealant layer, 14B: polypropylene resin layer, 15B: surface coat layer, 16B: barrier coat layer, 17B: second substrate, 20: test piece, 20x: inner surface, 20y: outer surface, 21: loop portion, 22: intermediate portion, 23: fixing portion, 25: loop stiffness measuring device, 26: chuck portion, 26A: first chuck, 26B: second chuck, 27: support member, 28: load cell, 60: lid material, 61: container portion , 62: container, 63: storage section, 64: flange, 65: opening, 66: contents, 67: gripping section, 70: test piece, 70: test piece, 71: substrate side, 72: sealant layer side, 73: gripping tool, 110: test piece, 111: needle, A: vacuum container, B: unwinding section, C: film formation drum, D: winding section, E: transport roll, F: evaporation source, G: reaction gas supply section, H: deposition protection box, I: evaporation material, J: plasma gun, A1: vacuum container, B1: unwinding section, C1: cooling electrode drum, D1: winding section, E1: transport 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 laminate, The device includes at least a first substrate, a vapor-deposited film, and a sealant layer, the first base material includes a polypropylene resin layer and a surface resin layer provided on one surface of the polypropylene resin layer, the vapor-deposited film is provided on a surface resin layer of the first substrate, The first substrate has been subjected to a stretching treatment, the surface resin layer contains a resin material having a melting point of 180°C or higher, the resin material is one or more resin materials selected from nylon 6, nylon 6,6, and MXD nylon, the vapor-deposited film is composed of an inorganic oxide, the sealant layer comprises a polyolefin having a melting point of 110°C or higher; The sealant layer is an easy-peel sealant layer in which the polyolefin is polypropylene.

2. The laminate according to claim 1 , wherein the surface resin layer is provided on the polypropylene resin layer.

3. the first base material includes an adhesive resin layer between the polypropylene resin layer and the surface resin layer, the adhesive resin layer is provided on the polypropylene resin layer, The laminate according to claim 1 , wherein the surface resin layer is provided on the adhesive resin layer.

4. The laminate according to any one of claims 1 to 3, wherein the surface resin layer contains a resin material having a melting point of 180°C or higher and 265°C or lower.

5. The resin material has a melting point TA, The polypropylene of the polypropylene resin layer has a melting point TB, The laminate according to any one of claims 1 to 4, wherein the difference between the melting point TA and the melting point TB is 20°C or more and 80°C or less.

6. The laminate according to any one of claims 1 to 5, wherein the ratio of the thickness of the surface resin layer to the total thickness of the first substrate is 1% or more and 10% or less.

7. The laminate according to any one of claims 1 to 6, wherein the first substrate is a co-extruded film.

8. The easy-peel sealant layer has a sea-island structure, The laminate according to any one of claims 1 to 7, wherein the sea-island structure includes a sea portion made of polypropylene and island portions made of high-density polyethylene.

9. The laminate according to any one of claims 1 to 8, further comprising a second substrate.

10. The laminate of claim 9 , wherein the second substrate comprises polypropylene.

11. The laminate according to claim 9 or 10, wherein the first substrate and the vapor-deposited film are located between the second substrate and the sealant layer.

12. an intermediate layer is provided between the vapor-deposited film and the sealant layer; The laminate according to claim 9 or 10, wherein the intermediate layer is the second substrate.

13. The laminate according to claim 12, wherein the intermediate layer is made of a polypropylene resin film that has been subjected to a stretching treatment.

14. a barrier coating layer is further provided between the vapor deposition film and the sealant layer; The laminate according to any one of claims 1 to 13, wherein the barrier coat layer comprises a hydrolysate of a metal alkoxide or a hydrolysis condensate of a metal alkoxide.

15. A lid material comprising the laminate according to any one of claims 1 to 14.

16. A packaging container using the lid material according to claim 15, wherein the sealant layer of the lid material is heat-sealed in a state where it is overlapped so as to contact the opening of the container body.

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