Laminate, packaging material, and package

Abstract

A laminate (100) comprising: a stretched base material layer (A); an extruded resin layer (B); and a sealant layer (C) in the stated order, wherein the stretched base material layer (A) includes a base material layer (A1) containing a high-density polyethylene (a1) and a base material layer (A2) containing a linear low-density polyethylene (a2), the base material layer (A2) is positioned on one surface of the base material layer (A1), the base material layer (A2) is in contact with the extruded resin layer (B), the sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer, and the ionomer resin layer (C1) is positioned in the sealant layer (C) on the side closer to the surface of the laminate (100).

Description

Laminates, packaging materials, and packaging

[0001] This invention relates to laminates, packaging materials, and packaging bodies.

[0002] As an example of a laminate, laminates used in packaging materials are known. And as a technology related to laminates used in packaging materials, for example, the technology described in Patent Document 1 can be cited.

[0003] Patent Document 1 describes a laminated film comprising at least a base layer (A) and an ionomer resin layer (B) provided on one side of the base layer (A) and containing an ionomer (B1) of an ethylene-unsaturated carboxylic acid copolymer, wherein when the content of unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid copolymer (B2) constituting the ethylene-unsaturated carboxylic acid copolymer ionomer (B1) is X [mass%] and the degree of neutralization of the ethylene-unsaturated carboxylic acid copolymer ionomer (B1) is Y [mol%], the metal ion content expressed as X × Y / 100 is greater than 5.0 and less than or equal to 20.0. Patent Document 1 describes a laminated film that can provide a laminated film with excellent tear resistance.

[0004] International Publication No. 2019 / 188696

[0005] This invention provides a laminate with an improved balance of film impact strength and puncture strength performance.

[0006] According to the present invention, the following laminates, packaging materials, and packaging bodies are provided.

[0007] [1] A laminate comprising a stretched base material layer (A), an extruded resin layer (B), and a sealant layer (C) in this order, wherein the stretched base material layer (A) comprises a base material layer (A1) containing high-density polyethylene (a1) and a base material layer (A2) containing linear low-density polyethylene (a2), the base material layer (A2) containing linear low-density polyethylene (a2) is located on one side of the base material layer (A1) containing high-density polyethylene (a1), the base material layer (A2) containing linear low-density polyethylene (a2) is in contact with the extruded resin layer (B), the sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer, and the ionomer resin layer (C1) is located at least on the surface side of the laminate in the sealant layer (C), [1] A laminate in which the content of the ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer in the ionomer resin layer (C1) is 80% by mass or more when the entire ionomer resin layer (C1) is considered to be 100% by mass. [2] The laminate according to [1], wherein the stretched base layer (A) further comprises a base layer (A3) containing linear low-density polyethylene (a3), and the base layer (A3) containing linear low-density polyethylene (a3) ​​is located on the side of the base layer (A1) containing high-density polyethylene (a1) that is opposite to the one side. [3] The laminate according to [1] or [2], wherein the extruded resin layer (B) contains low-density polyethylene (b1). [4] The laminate according to any one of [1] to [3], wherein the extruded resin layer (B) contains at least one selected from the group consisting of an ethylene-unsaturated carboxylic acid copolymer (b2) and an ionomer (b3) of an ethylene-unsaturated carboxylic acid copolymer. [5] The laminate according to any one of [1] to [4], wherein the sealant layer (C) is made of the ionomer resin layer (C1). [6] The laminate according to any one of [1] to [4], wherein the sealant layer (C) further comprises a polyethylene resin layer (C2), and the polyethylene resin layer (C2) is in contact with the extruded resin layer (B).[7] The laminate according to [6], wherein the polyethylene resin layer (C2) is made of a composition comprising at least one selected from the group consisting of linear low-density polyethylene and low-density polyethylene. [8] A packaging material comprising the laminate according to any one of [1] to [7]. [9] A package comprising the packaging material according to [8] and an article packaged with the packaging material.

[0008] According to the present invention, it is possible to provide a laminate with an improved balance of film impact strength and puncture strength performance.

[0009] This is a schematic cross-sectional view illustrating an example of the structure of the laminate according to this embodiment. This is a schematic cross-sectional view illustrating an example of the structure of the laminate according to this embodiment. This is a schematic cross-sectional view illustrating an example of the structure of the laminate according to this embodiment.

[0010] Embodiments of the present invention will be described below with reference to the drawings. Note that the drawings are simplified diagrams and do not correspond to the actual dimensional ratios. Unless otherwise specified, the numerical range "A to B" represents A or greater and B or less. (Meth)acrylic is a concept that encompasses both acrylic and methacrylic. In this specification, the "substrate layer (A1) containing high-density polyethylene (a1)" may be abbreviated as "substrate layer (A1)". Other layers may also be abbreviated in the same way.

[0011] [Laminate] Figures 1 to 3 are schematic cross-sectional views showing an example of the structure of the laminate of this embodiment. The laminate of this embodiment is a laminate 100 comprising a stretched base material layer (A), an extruded resin layer (B), and a sealant layer (C) in this order, wherein the stretched base material layer (A) comprises a base material layer (A1) containing high-density polyethylene (a1) and a base material layer (A2) containing linear low-density polyethylene (a2), and the base material layer (A2) containing linear low-density polyethylene (a1) is located on one side of the base material layer (A1) containing high-density polyethylene (a1), and the base material layer (a2) containing linear low-density polyethylene ( A2) is in contact with the extruded resin layer (B), and the sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer, the ionomer resin layer (C1) is located at least on the surface side of the laminate in the sealant layer (C), and the content of the ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer in the ionomer resin layer (C1) is 80% by mass or more when the total mass of the ionomer resin layer (C1) is taken as 100% by mass.

[0012] The laminate of this embodiment provides a laminate with improved performance balance between film impact strength and puncture strength. Furthermore, the laminate of this embodiment provides a laminate with improved tear resistance. Moreover, the laminate of this embodiment provides a laminate capable of improving low-temperature seal strength. Low-temperature seal strength is, for example, the seal strength at 110°C.

[0013] The film impact strength of the laminate 100 is preferably 9,500 J / m or more, more preferably 10,000 J / m or more, and even more preferably 10,500 J / m or more, from the viewpoint of further improving the strength of the laminate, and the upper limit is not particularly limited, but may be, for example, 20,000 J / m or less, 18,000 J / m or less, or 16,000 J / m or less.

[0014] The film impact strength of the laminate refers to the value measured in accordance with ASTM D3420, specifically, the value measured by the measurement method described in the examples.

[0015] The puncture strength of the laminate 100 is preferably 73 N / mm or more, more preferably 76 N / mm or more, and even more preferably 80 N / mm or more, from the viewpoint of further improving the strength of the laminate, and the upper limit is not particularly limited, but may be, for example, 200 N / mm or less, 150 N / mm or less, or 100 N / mm or less.

[0016] The puncture strength of the laminate refers to the value measured in accordance with JIS Z1707:2019, specifically, the value measured by the measurement method described in the examples.

[0017] The Elmendorff tear strength of the laminate 100 in the MD direction is preferably 1150 N / cm or less, more preferably 1100 N / cm or less, and even more preferably 1050 N / cm or less, from the viewpoint of improving ease of tearing, and the lower limit is not particularly limited, but may be, for example, 20 N / cm or more, or 40 N / cm or more.

[0018] The Elmendorf tear strength in the MD direction of the laminate refers to the value measured according to JIS K7128-2:1998.

[0019] The heat seal strength of the laminate 100 is preferably 10.0 N / 15 mm or more, more preferably 11.0 N / 15 mm or more, and even more preferably 12.0 N / 15 mm or more, from the viewpoint of improving low-temperature seal strength. The upper limit is not particularly limited, but may be, for example, 50.0 N / 15 mm or less, 45.0 N / 15 mm or less, or 40.0 N / 15 mm or less.

[0020] The heat seal strength of the laminate refers to the peel strength when a 15 mm wide test piece, heat-sealed in the TD direction under the following conditions: temperature: 110°C, sealing pressure (actual pressure): 0.2 MPa, time: 0.5 seconds, and sealing width: 10 mm, is peeled in a T-shape in the MD direction at a tensile speed of 300 mm / min using a tensile testing machine in accordance with JIS Z1707:2019, with the sealant layers (C) in contact with each other. Specifically, it refers to the value measured by the measurement method described in the examples.

[0021] Hereinafter, each layer constituting the laminate 100 will be specifically described.

[0022] <Stretched base material layer (A)> The laminate 100 comprises a stretched base material layer (A). The stretched base material layer (A) comprises a base material layer (A1) containing high-density polyethylene (a1) and a base material layer (A2) containing linear low-density polyethylene (a2). When the laminate 100 comprises the stretched base material layer (A), the heat resistance, rigidity, dimensional stability and the like of the laminate 100 can be further improved.

[0023] The stretched base material layer (A) is not particularly limited as long as it is a layer composed of a stretched film, and may be a uniaxially stretched film or a biaxially stretched film, but is preferably a uniaxially stretched film.

[0024] Hereinafter, each layer constituting the stretched base material layer (A) will be specifically described.

[0025] (Base material layer (A1)) The stretched base material layer (A) comprises a base material layer (A1) containing high-density polyethylene (a1). When the stretched base material layer (A) comprises the base material layer (A1), the heat resistance, rigidity, dimensional stability and the like of the laminate 100 can be improved.

[0026] From the viewpoint of further improving the heat resistance, rigidity, dimensional stability and the like of the laminate 100, the density of the high-density polyethylene (a1) is preferably 945 kg / m ３ or more and 970 kg / m ３ or less, more preferably 948 kg / m ３ or more and 968 kg / m ３ or less, still more preferably 949 kg / m ３ or more and 965 kg / m ３ or less. The density of high-density polyethylene (a1) means a value measured by measurement in accordance with JIS K7112:1999.

[0027] The melt flow rate (MFR) of high-density polyethylene (a1) is preferably 0.1 g / 10 min to 50.0 g / 10 min, more preferably 0.5 g / 10 min to 30.0 g / 10 min, and even more preferably 0.5 g / 10 min to 20.0 g / 10 min, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc. of the laminate 100. The melt flow rate (MFR) of high-density polyethylene (a1) refers to the value measured under conditions of 190°C and 2160 g load, in accordance with JIS K7210:1999.

[0028] The method for producing high-density polyethylene (a1) is not particularly limited and can be produced by known methods, for example. High-density polyethylene (a1) may be, for example, commercially available high-density polyethylene. Examples of commercially available high-density polyethylene include Hyzex (manufactured by Prime Polymer Co., Ltd.).

[0029] The content of high-density polyethylene (a1) in the base layer (A1) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the entire base layer (A1) is considered to be 100% by mass, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc. of the laminate 100.

[0030] The thickness of the base layer (A1) is preferably 5 μm to 50 μm, more preferably 8 μm to 30 μm, and even more preferably 10 μm to 20 μm, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc., of the laminate 100.

[0031] The thickness of the base material layer (A1), when the entire stretched base material layer (A) is considered as 100%, is preferably 30% to 90%, more preferably 40% to 80%, and even more preferably 50% to 70%, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc., of the laminate 100.

[0032] When the thickness of the base material layer (A2) is taken as 1, the thickness of the base material layer (A1) is preferably 1 or more and 5 or less, more preferably 2 or more and 4 or less, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability and the like of the laminate 100.

[0033] (Base Material Layer (A2)) The stretched base material layer (A) comprises a base material layer (A2) containing linear low-density polyethylene (a2). The base material layer (A2) is located on one surface of the base material layer (A1). Further, the base material layer (A2) is in contact with the extruded resin layer (B). When the stretched base material layer (A) comprises the base material layer (A2), the performance balance between film impact strength and puncture strength can be improved.

[0034] The density of the linear low-density polyethylene (a2) is, from the viewpoint of further improving the performance balance between film impact strength and puncture strength, preferably 900 kg / m ３ or more and 940 kg / m ３ or less, more preferably 910 kg / m ３ or more and 935 kg / m ３ or less, still more preferably 915 kg / m ３ or more and 930 kg / m ３ or less. The density of the linear low-density polyethylene (a2) means a value measured by measurement in accordance with JIS K7112:1999.

[0035] The melt flow rate (MFR) of the linear low-density polyethylene (a2) is, from the viewpoint of further improving the performance balance between film impact strength and puncture strength, preferably 0.1 g / 10 min or more and 50.0 g / 10 min or less, more preferably 0.5 g / 10 min or more and 30.0 g / 10 min or less, still more preferably 0.5 g / 10 min or more and 20.0 g / 10 min or less. The melt flow rate (MFR) of the linear low-density polyethylene (a2) means a value measured under conditions of 190°C and a 2160 g load in accordance with JIS K7210:1999.

[0036] The method for producing linear low-density polyethylene (a2) is not particularly limited and can be produced by known methods, for example. For linear low-density polyethylene (a2), commercially available linear low-density polyethylene may be used. Examples of commercially available linear low-density polyethylene include Evolu (manufactured by Prime Polymer Co., Ltd.) and Ultzex ​​(manufactured by Prime Polymer Co., Ltd.).

[0037] The content of linear low-density polyethylene (a2) in the base layer (A2) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the entire base layer (A2) is considered to be 100% by mass, from the viewpoint of further improving the performance balance of film impact strength and puncture strength.

[0038] The thickness of the base layer (A2) is preferably 1 μm to 30 μm, more preferably 2 μm to 20 μm, and even more preferably 3 μm to 10 μm, from the viewpoint of further improving the balance between film impact strength and puncture strength performance.

[0039] The thickness of the base material layer (A2), when the entire stretched base material layer (A) is considered as 100%, is preferably 5% to 50%, more preferably 7% to 40%, and even more preferably 10% to 30%, from the viewpoint of further improving the balance of film impact strength and puncture strength performance.

[0040] (Base layer (A3)) The stretched base layer (A) preferably further comprises a base layer (A3) containing linear low-density polyethylene (a3). The base layer (A3) is located on the side of the base layer (A1) opposite to the side where the base layer (A2) is located. By having the base layer (A3) in the stretched base layer (A), the balance between film impact strength and puncture strength performance can be further improved.

[0041] A preferred embodiment of linear low-density polyethylene (a3) ​​is the same as a preferred embodiment of linear low-density polyethylene (a2).

[0042] The content of linear low-density polyethylene (a3) ​​in the base layer (A3) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the entire base layer (A3) is considered to be 100% by mass, from the viewpoint of further improving the performance balance of film impact strength and puncture strength.

[0043] The thickness of the base layer (A3) is preferably 1 μm to 30 μm, more preferably 2 μm to 20 μm, and even more preferably 3 μm to 10 μm, from the viewpoint of further improving the balance between film impact strength and puncture strength performance.

[0044] The thickness of the base material layer (A3), when the entire stretched base material layer (A) is considered as 100%, is preferably 5% to 50%, more preferably 7% to 40%, and even more preferably 10% to 30%, from the viewpoint of further improving the balance of film impact strength and puncture strength performance.

[0045] The substrate layers (A1) to (A3) may further contain other components. Examples of other components include one or more selected from the group consisting of plasticizers, antioxidants, ultraviolet absorbers, antistatic agents, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retardants, catalyst deactivators, inorganic fillers, organic fillers, impact resistance modifiers, slip agents, crosslinking agents, crosslinking aids, tackifiers, silane coupling agents, processing aids, mold release agents, hydrolysis inhibitors, heat stabilizers, antiblocking agents, antifogging agents, flame retardants, flame retardant aids, light diffusing agents, antibacterial agents, antifungal agents, and dispersants.

[0046] The thickness of the stretched base material layer (A) is preferably 7 μm to 70 μm, more preferably 10 μm to 50 μm, and even more preferably 15 μm to 40 μm, from the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc., of the laminate 100.

[0047] From the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc. of the laminate 100, the thickness of the stretched base material layer (A) is preferably 5% to 70%, more preferably 10% to 50%, and even more preferably 15% to 40%, when the total thickness of the stretched base material layer (A), the extruded resin layer (B), and the sealant layer (C) is taken as 100%.

[0048] From the viewpoint of further improving the heat resistance, rigidity, dimensional stability, etc. of the laminate 100, the stretched base material layer (A) is preferably a layer in which base material layer (A1) and base material layer (A2) are in direct contact, and more preferably a layer in which base material layer (A1) and base material layer (A2) are in direct contact, and base material layer (A1) and base material layer (A3) are in direct contact.

[0049] <Extruded Resin Layer (B)> The laminate 100 includes an extruded resin layer (B). The extruded resin layer (B) is not particularly limited as long as it is a layer composed of extruded resin. By including the extruded resin layer (B) in the laminate 100, the balance between film impact strength and puncture strength performance can be improved.

[0050] The extruded resin layer (B) preferably contains low-density polyethylene (b1) from the viewpoint of further improving the balance between film impact strength and puncture strength performance.

[0051] The density of low-density polyethylene (b1) is preferably 910 kg / m³ from the viewpoint of further improving the balance between film impact strength and puncture strength performance. ３ More than 940kg / m ３ More preferably, 913 kg / m ３ More than 935kg / m ３ More preferably, 915 kg / m ３ More than 930kg / m ３The following applies: The density of low-density polyethylene (b1) refers to the value measured according to JIS K7112:1999.

[0052] The melt flow rate (MFR) of low-density polyethylene (b1) is preferably 1.0 g / 10 min to 30.0 g / 10 min, more preferably 3.0 g / 10 min to 20.0 g / 10 min, and even more preferably 5.0 g / 10 min to 10.0 g / 10 min, from the viewpoint of further improving the balance of film impact strength and puncture strength performance. The melt flow rate (MFR) of low-density polyethylene (b1) refers to the value measured under conditions of 190°C and 2160 g load, in accordance with JIS K7210:1999.

[0053] The content of low-density polyethylene (b1) in the extruded resin layer (B) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the total content of the extruded resin layer (B) is considered as 100% by mass, in order to further improve the balance of film impact strength and puncture strength performance.

[0054] The method for producing low-density polyethylene (b1) is not particularly limited and can be produced by known methods, for example. Low-density polyethylene (b1) may be, for example, commercially available linear low-density polyethylene. Examples of commercially available low-density polyethylene include Mirason (manufactured by Mitsui Dow Polychemical Co., Ltd.).

[0055] The extruded resin layer (B) preferably includes at least one selected from the group consisting of ethylene-unsaturated carboxylic acid copolymers (b2) and ionomers (b3) of ethylene-unsaturated carboxylic acid copolymers, from the viewpoint of further improving the balance of film impact strength and puncture strength performance.

[0056] The ethylene-unsaturated carboxylic acid copolymer (b2) is a copolymer in which at least ethylene and an unsaturated carboxylic acid are copolymerized. The ethylene-unsaturated carboxylic acid copolymer (b2) may also be a ternary or more polypolymer in which a third copolymer component other than ethylene and an unsaturated carboxylic acid is copolymerized.

[0057] In the ethylene-unsaturated carboxylic acid copolymer (b2), the unsaturated carboxylic acid specifically includes one or more selected from the group consisting of acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, maleic acid, and maleic acid monoesters (monomethyl maleic acid, monoethyl maleic acid, etc.), preferably including one or more selected from the group consisting of acrylic acid and methacrylic acid, and more preferably including methacrylic acid.

[0058] In the ethylene-unsaturated carboxylic acid copolymer (b2), the third copolymer component other than ethylene and unsaturated carboxylic acid includes, for example, at least one selected from the group consisting of unsaturated carboxylic acid esters, vinyl esters, and unsaturated hydrocarbons, and preferably includes an unsaturated carboxylic acid ester.

[0059] The unsaturated carboxylic acid ester comprises, for example, one or more selected from the group consisting of alkyl (meth)acrylates and alkyl maleates, preferably comprising alkyl (meth)acrylates, more preferably comprising alkyl (meth)acrylates having 1 to 6 carbon atoms in the alkyl moiety, and even more preferably comprising alkyl (meth)acrylates having 1 to 4 carbon atoms in the alkyl moiety.

[0060] The alkyl (meth)acrylate ester includes, for example, one or more selected from the group consisting of methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate, and isobutyl methacrylate, preferably including at least one selected from the group consisting of isobutyl acrylate and isobutyl methacrylate, and more preferably including isobutyl acrylate.

[0061] The alkyl maleate includes, for example, at least one selected from the group consisting of dimethyl maleate and diethyl maleate.

[0062] The ethylene-unsaturated carboxylic acid copolymer (b2) preferably comprises one selected from the group consisting of ethylene-methacrylic acid-isobutyl acrylate copolymer, ethylene-acrylic acid-isobutyl acrylate copolymer, ethylene-methacrylic acid-isobutyl methacrylate copolymer, and ethylene-acrylic acid-isobutyl methacrylate copolymer, and more preferably comprises ethylene-methacrylic acid-isobutyl acrylate copolymer.

[0063] The content of ethylene-derived structural units in the ethylene-unsaturated carboxylic acid copolymer (b2) is preferably 70% to 98% by mass, more preferably 78% to 96% by mass, and even more preferably 85% to 94% by mass, when the total amount of structural units in the ethylene-unsaturated carboxylic acid copolymer (b2) is taken as 100% by mass, from the viewpoint of further improving the balance of film impact strength and puncture strength performance.

[0064] The content of unsaturated carboxylic acid-derived constituent units in the ethylene-unsaturated carboxylic acid copolymer (b2) is preferably 1% to 15% by mass, more preferably 2% to 10% by mass, and even more preferably 3% to 5% by mass, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid copolymer (b2) is taken as 100% by mass, in order to further improve the balance of film impact strength and puncture strength performance.

[0065] The content of unsaturated carboxylic acid ester-derived constituent units in the ethylene-unsaturated carboxylic acid copolymer (b2) is preferably 1% to 15% by mass, more preferably 3% to 12% by mass, and even more preferably 5% to 10% by mass, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid copolymer (b2) is taken as 100% by mass, in order to further improve the balance of film impact strength and puncture strength performance.

[0066] The content of unsaturated carboxylic acid-derived constituent units and unsaturated carboxylic acid ester-derived constituent units in the ethylene-unsaturated carboxylic acid copolymer (b2) can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0067] The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer (b2) is preferably 1.0 g / 10 min to 40.0 g / 10 min, more preferably 5.0 g / 10 min to 30.0 g / 10 min, and even more preferably 10.0 g / 10 min to 20.0 g / 10 min, from the viewpoint of further improving the balance of film impact strength and puncture strength performance. The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer (b2) refers to the value measured under conditions of 190°C and 2160 g load, in accordance with JIS K7210:1999.

[0068] The density of the ethylene-unsaturated carboxylic acid copolymer (b2) is preferably 800 kg / m², from the viewpoint of further improving the balance between film impact strength and puncture strength performance. ３ More than 1100kg / m ３More preferably, 850 kg / m ３ More than 1050kg / m ３ More preferably, 900 kg / m ３ More than 1000kg / m ３ The following applies:

[0069] The content of the ethylene-unsaturated carboxylic acid copolymer (b2) in the extruded resin layer (B) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the total content of the extruded resin layer (B) is considered as 100% by mass, from the viewpoint of further improving the balance of film impact strength and puncture strength performance.

[0070] The extruded resin layer (B) preferably contains an ionomer (b3) of an ethylene-unsaturated carboxylic acid copolymer, from the viewpoint of further improving the film impact strength, puncture strength, and tear resistance of the laminate 100.

[0071] In the ethylene-unsaturated carboxylic acid copolymer, which is the base resin of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer, each copolymer component can be the same as the copolymer components of the ethylene-unsaturated carboxylic acid copolymer (b2), for example.

[0072] The base resin of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer preferably comprises at least one selected from the group consisting of ethylene-methacrylic acid copolymer and ethylene-acrylic acid copolymer, and more preferably comprises ethylene-methacrylic acid copolymer, from the viewpoint of further improving the film impact strength, puncture strength, and tear resistance of the laminate 100.

[0073] The content of ethylene-derived structural units in the base resin of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably 70% to 95% by mass, more preferably 75% to 92% by mass, and even more preferably 80% to 90% by mass, when the total amount of structural units in the base resin is 100% by mass, in order to further improve the film impact strength, puncture strength, and tearability of the laminate 100.

[0074] The content of unsaturated carboxylic acid-derived structural units in the base resin of the ethylene-unsaturated carboxylic acid copolymer ionomer (b3) is preferably 5% to 30% by mass, more preferably 7% to 25% by mass, and even more preferably 8% to 20% by mass, when the total amount of structural units in the base resin is 100% by mass, in order to further improve the film impact strength, puncture strength, and tearability of the laminate 100.

[0075] The content of unsaturated carboxylic acid-derived constituent units in the base resin of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0076] Examples of metal ions in the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer include alkali metal ions such as lithium ions, potassium ions, and sodium ions; and polyvalent metal ions such as calcium ions, magnesium ions, zinc ions, aluminum ions, and barium ions.

[0077] The metal ions in the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer preferably include at least one selected from the group consisting of zinc ions, sodium ions, and magnesium ions, more preferably at least one selected from the group consisting of zinc ions and sodium ions, and even more preferably zinc ions.

[0078] When the metal ions in the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer include zinc ions, the degree of neutralization of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably within the following numerical range. From the viewpoint of further improving the tear resistance, heat resistance, and processability of the laminate 100, the degree of neutralization of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably 5 mol% to 85 mol%, more preferably 10 mol% to 85 mol%, and even more preferably 15 mol% to 80 mol%.

[0079] When the metal ions in the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer include sodium ions, the degree of neutralization of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably within the following numerical range. From the viewpoint of further improving the tear resistance, heat resistance, and processability of the laminate 100, the degree of neutralization of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably 20 mol% to 65 mol%, more preferably 25 mol% to 60 mol%, and even more preferably 30 mol% to 55 mol%.

[0080] The degree of neutralization of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by incineration residue analysis.

[0081] The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer ionomer (b3) is preferably 0.5 g / 10 min to 20.0 g / 10 min, more preferably 1.0 g / 10 min to 15.0 g / 10 min, and even more preferably 3.0 g / 10 min to 10.0 g / 10 min, from the viewpoint of further improving the film impact strength, puncture strength, and tear resistance of the laminate 100. The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer ionomer (b3) refers to the value measured under conditions of 190°C and a 2160 g load, in accordance with JIS K7210:1999.

[0082] The density of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer is preferably 800 kg / m², from the viewpoint of further improving the film impact strength, puncture strength, and tear resistance of the laminate 100. ３ More than 1100kg / m ３ More preferably, 850 kg / m ３ More than 1050kg / m ３ More preferably, 900 kg / m ３ More than 1000kg / m ３ The following applies: The density of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer refers to the value measured according to JIS K7112:1999.

[0083] The content of the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer in the extruded resin layer (B) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the total content of the extruded resin layer (B) is considered as 100% by mass, from the viewpoint of further improving the film impact strength, puncture strength, and ease of tearing of the laminate 100.

[0084] The extruded resin layer (B) may further contain other components. Examples of other components include one or more selected from the group consisting of plasticizers, antioxidants, ultraviolet absorbers, antistatic agents, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retardants, catalyst deactivators, inorganic fillers, organic fillers, impact resistance modifiers, slip agents, crosslinking agents, crosslinking aids, tackifiers, silane coupling agents, processing aids, mold release agents, hydrolysis inhibitors, heat stabilizers, antiblocking agents, antifogging agents, flame retardants, flame retardant aids, light diffusing agents, antibacterial agents, antifungal agents, and dispersants.

[0085] The thickness of the extruded resin layer (B) is preferably 5 μm to 30 μm, more preferably 8 μm to 25 μm, and even more preferably 10 μm to 20 μm, from the viewpoint of further improving the balance between film impact strength and puncture strength performance.

[0086] The thickness of the extruded resin layer (B) is preferably 3% to 50%, more preferably 5% to 30%, and even more preferably 10% to 25%, from the viewpoint of further improving the balance of film impact strength and puncture strength performance, when the total thickness of the stretched substrate layer (A), the extruded resin layer (B), and the sealant layer (C) is taken as 100%.

[0087] The extruded resin layer (B) may be a single layer or a multilayer.

[0088] <Sealant layer (C)> The laminate 100 includes a sealant layer (C). The sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer.

[0089] The following describes in detail each layer that makes up the sealant layer (C).

[0090] (Ionomer resin layer (C1)) The sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer. The ionomer resin layer (C1) is located at least on the surface side of the laminate in the sealant layer (C). The surface side of the laminate in the sealant layer (C) refers to the inside side when used as packaging material (the side on which the article packaged by the packaging material is located). By comprising the ionomer resin layer (C1) in the sealant layer (C), the balance between the film impact strength and puncture strength of the laminate 100 can be improved. Furthermore, by comprising the ionomer resin layer (C1) in the sealant layer (C), the tear resistance and low-temperature seal strength of the laminate 100 can be improved.

[0091] In the ethylene-unsaturated carboxylic acid copolymer, which is the base resin of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer, each copolymer component can be the same as, for example, the copolymer components of the ethylene-unsaturated carboxylic acid copolymer (b2).

[0092] The base resin of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer preferably includes one selected from the group consisting of ethylene-methacrylic acid-isobutyl acrylate copolymer, ethylene-acrylic acid-isobutyl acrylate copolymer, ethylene-methacrylic acid-isobutyl methacrylate copolymer, and ethylene-acrylic acid-isobutyl methacrylate copolymer, and more preferably includes ethylene-methacrylic acid-isobutyl acrylate copolymer.

[0093] The content of ethylene-derived structural units in the base resin of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably 50% to 94% by mass, more preferably 60% to 90% by mass, and even more preferably 70% to 86% by mass, when the total amount of structural units in the base resin is 100% by mass, in order to further improve the performance balance of the film impact strength and puncture strength of the laminate 100.

[0094] The content of unsaturated carboxylic acid-derived constituent units in the base resin of the ethylene-unsaturated carboxylic acid copolymer ionomer (c1) is preferably 3% to 25% by mass, more preferably 5% to 20% by mass, and even more preferably 7% to 15% by mass, when the total amount of constituent units in the base resin is 100% by mass, in order to further improve the performance balance of film impact strength and puncture strength of the laminate 100.

[0095] The content of unsaturated carboxylic acid ester-derived constituent units in the base resin of the ethylene-unsaturated carboxylic acid copolymer ionomer (c1) is preferably 3% to 25% by mass, more preferably 5% to 20% by mass, and even more preferably 7% to 15% by mass, when the total amount of constituent units in the base resin is 100% by mass, in order to further improve the performance balance of film impact strength and puncture strength of the laminate 100.

[0096] The content of unsaturated carboxylic acid-derived structural units and unsaturated carboxylic acid ester-derived structural units in the base resin of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0097] The metal ions in the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer are, for example, similar to the metal ions in the ionomer (b3) of the ethylene-unsaturated carboxylic acid copolymer. From the viewpoint of further improving the balance of film impact strength and puncture strength performance of the laminate 100, the metal ions in the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer preferably include at least one selected from the group consisting of zinc ions, sodium ions, and magnesium ions, more preferably include at least one selected from the group consisting of zinc ions and sodium ions, and even more preferably include zinc ions.

[0098] When the metal ions in the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer include zinc ions, the degree of neutralization in the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably within the following numerical range. From the viewpoint of further improving the tear resistance, heat resistance, and processability of the laminate 100, the degree of neutralization of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably 15 mol% to 85 mol%, more preferably 30 mol% to 80 mol%, and even more preferably 50 mol% to 75 mol%.

[0099] When the metal ions in the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer include sodium ions, the degree of neutralization of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably within the following numerical range. From the viewpoint of further improving the tear resistance, heat resistance, and processability of the laminate 100, the degree of neutralization of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably 20 mol% to 65 mol%, more preferably 25 mol% to 60 mol%, and even more preferably 30 mol% to 55 mol%.

[0100] The degree of neutralization of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer can be measured, for example, by incineration residue analysis.

[0101] The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer ionomer (c1) is preferably 0.3 g / 10 min to 40.0 g / 10 min, more preferably 0.5 g / 10 min to 30.0 g / 10 min, and even more preferably 0.7 g / 10 min to 20.0 g / 10 min, from the viewpoint of improving the performance balance of film impact strength and puncture strength of the laminate 100. The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid copolymer ionomer (c1) refers to the value measured under conditions of 190°C and 2160 g load, in accordance with JIS K7210:1999.

[0102] From the viewpoint of improving the balance between the film impact strength and puncture strength performance of the laminate 100, the density of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer is preferably 800 kg / m². ３ More than 1100kg / m ３ More preferably, 850 kg / m ３ More than 1050kg / m ３ More preferably, 900 kg / m ３ More than 1000kg / m ３ The following applies: The density of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer refers to the value measured according to JIS K7112:1999.

[0103] The content of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer in the ionomer resin layer (C1) is 80% by mass or more, when the total ionomer resin layer (C1) is considered to be 100% by mass, from the viewpoint of improving the performance balance of film impact strength and puncture strength of the laminate 100. The content of the ionomer (c1) of the ethylene-unsaturated carboxylic acid copolymer in the ionomer resin layer (C1) is preferably 85% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, when the total ionomer resin layer (C1) is considered to be 100% by mass, from the viewpoint of further improving the performance balance of film impact strength and puncture strength of the laminate 100.

[0104] The ionomer resin layer (C1) may further contain other components. These other components include at least one selected from the group consisting of antiblocking agents, slip agents, polyolefin resins, antistatic agents (e.g., polymer-type antistatic agents), plasticizers, antioxidants, UV absorbers, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retardants, catalyst deactivators, inorganic fillers, organic fillers, impact resistance modifiers, slip agents, crosslinking agents, crosslinking aids, tackifiers, silane coupling agents, processing aids, mold release agents, hydrolysis inhibitors, heat stabilizers, antifogging agents, flame retardants, flame retardant aids, light diffusing agents, antibacterial agents, antifungal agents, and dispersants.

[0105] The antiblocking agent comprises, for example, at least one selected from the group consisting of talc, silica, calcium carbonate, synthetic zeolite, and starch, and preferably at least one selected from the group consisting of synthetic zeolite and silica. The content of the antiblocking agent in the ionomer resin layer (C1) is, for example, 0.5% by mass or more and 5% by mass or less, and preferably 1% by mass or more and 4% by mass or less, when the total ionomer resin layer (C1) is considered to be 100% by mass.

[0106] The slip agent includes, for example, hydrocarbon waxes such as liquid paraffin, paraffin wax, microwax, and polyethylene wax; fatty acid-based or higher alcohol-based waxes such as stearic acid, 1,2-hydroxystearic acid, and stearyl alcohol; amide waxes such as stearamide, oleamide, erucamide, behenamide, methylenebisstearate, ethylenebisstearate, ethylenebisoleamide, and N-oleyl palmitamide; metal soaps such as lead stearate, zinc stearate, calcium stearate, and magnesium stearate; silicone; and preferably includes at least one selected from the group consisting of behenamide, N-oleyl palmitamide, and erucamide. The slip agent content in the ionomer resin layer (C1) is, for example, 0.05% by mass or more and 3% by mass or less, preferably 0.4% by mass or more and 2% by mass or less, when the total mass of the ionomer resin layer (C1) is considered to be 100% by mass.

[0107] The polyolefin resin includes, for example, at least one selected from the group consisting of low-density polyethylene, linear low-density polyethylene, ethylene-unsaturated carboxylic acid copolymer, polypropylene, polybutene, and polybutadiene. The polyolefin resin content in the ionomer resin layer (C1) is, for example, 1% by mass or more and 10% by mass or less, when the total mass of the ionomer resin layer (C1) is considered to be 100% by mass.

[0108] (Polyethylene resin layer (C2)) The sealant layer (C) preferably further comprises a polyethylene resin layer (C2). The polyethylene resin layer (C2) is in contact with the extruded resin layer (B). The polyethylene resin layer (C2) preferably is in contact with the ionomer resin layer (C1). By further comprising the polyethylene resin layer (C2) in the sealant layer (C), the balance of performance of the laminate 100 in terms of film impact strength, puncture strength, and other properties required for packaging materials can be further improved.

[0109] The polyethylene resin layer (C2) contains polyethylene resin (c2) and, from the viewpoint of further improving the balance of performance of the laminate 100 in terms of film impact strength, puncture strength, and other properties required for packaging materials, preferably contains at least one selected from the group consisting of linear low-density polyethylene and low-density polyethylene, and more preferably contains linear low-density polyethylene.

[0110] The melt flow rate (MFR) of the polyethylene resin (c2) is preferably 0.3 g / 10 min to 50.0 g / 10 min, more preferably 0.5 g / 10 min to 40.0 g / 10 min, and even more preferably 1.0 g / 10 min to 30.0 g / 10 min, from the viewpoint of further improving the performance balance of the film impact strength, puncture strength, and other properties required for packaging materials of the laminate 100. The melt flow rate (MFR) of the polyethylene resin (c2) refers to the value measured under conditions of 190°C and 2160 g load, in accordance with JIS K7210:1999.

[0111] From the viewpoint of further improving the balance of performance of the laminate 100, including film impact strength, puncture strength, and other properties required for packaging materials, the density of the polyethylene resin (c2) is preferably 900 kg / m³. ３ More than 940kg / m ３ More preferably, 910 kg / m ３ More than 935kg / m ３ More preferably, 915 kg / m ３ More than 930kg / m ３ The following applies: The density of polyethylene resin (c2) refers to the value measured according to JIS K7112:1999.

[0112] The content of polyethylene resin (c2) in the polyethylene resin layer (C2) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 80% to 100% by mass, even more preferably 90% to 100% by mass, even more preferably 95% to 100% by mass, and even more preferably 98% to 100% by mass, when the total polyethylene resin layer (C2) is considered as 100% by mass, in order to further improve the performance balance of the film impact strength, puncture strength, and other properties required for packaging materials of the laminate 100.

[0113] The polyethylene resin layer (C2) may further contain other components. Examples of other components include those similar to the other components of the ionomer resin layer (C1).

[0114] The thickness of the sealant layer (C) is preferably 10 μm to 100 μm, more preferably 10 μm to 90 μm, and even more preferably 10 μm to 80 μm, from the viewpoint of further improving the performance balance of the film impact strength and puncture strength of the laminate 100.

[0115] The thickness of the sealant layer (C) is preferably 20% to 90%, more preferably 30% to 80%, and even more preferably 40% to 70%, from the viewpoint of further improving the performance balance of the film impact strength and puncture strength of the laminate 100, when the total thickness of the stretched substrate layer (A), the extruded resin layer (B), and the sealant layer (C) is taken as 100%.

[0116] The sealant layer (C) is preferably an ionomer resin layer (C1) from the viewpoint of further improving the film impact strength, puncture strength, tear resistance, and low-temperature seal strength of the laminate 100.

[0117] When the sealant layer (C) consists of an ionomer resin layer (C1), the thickness of the ionomer resin layer (C1) is preferably 10 μm to 80 μm, more preferably 20 μm to 75 μm, and even more preferably 20 μm to 70 μm, from the viewpoint of further improving the film impact strength, puncture strength, tear resistance, and low-temperature seal strength of the laminate 100.

[0118] When the sealant layer (C) is multilayered, the thickness of the ionomer resin layer (C1) is preferably 5 μm to 70 μm, more preferably 5 μm to 50 μm, and even more preferably 5 μm to 30 μm, from the viewpoint of further improving the film impact strength, puncture strength, tearability, and low-temperature seal strength of the laminate 100. When the sealant layer (C) is multilayered, the thickness of the ionomer resin layer (C1) is preferably 5% to 95%, more preferably 10% to 70%, and even more preferably 15% to 50%, when the entire sealant layer (C) is considered as 100%.

[0119] The thickness of the polyethylene resin layer (C2) is preferably 10 μm to 90 μm, more preferably 20 μm to 70 μm, and even more preferably 30 μm to 60 μm, from the viewpoint of further improving the performance balance of the film impact strength, puncture strength, and other properties required for packaging materials of the laminate 100.

[0120] The thickness of the polyethylene resin layer (C2) is preferably 1 to 10, more preferably 2 to 8, and even more preferably 3 to 6, when the thickness of the ionomer resin layer (C1) is set to 1, from the viewpoint of further improving the performance balance of the film impact strength, puncture strength, tear resistance, low-temperature seal strength, and other properties required for packaging materials of the laminate 100.

[0121] <Other Layers> The laminate 100 may also include other layers as appropriate. Examples of other layers include a foam layer, a metal layer, an inorganic layer, a gas barrier layer, a hard coat layer, an adhesive layer, an anti-reflective layer, an anti-fouling layer, an anchor coat layer, and the like.

[0122] A preferred layer configuration for the laminate 100 is, for example, the layer configuration of the laminate 100 shown in Figure 2. That is, the laminate 100 preferably comprises a base layer (A3), a base layer (A1), a base layer (A2), an extruded resin layer (B), and an ionomer resin layer (C1) in this order. More preferably, the layers of the laminate 100 are in contact with each other. With the above layer configuration, the film impact strength, puncture strength, tear resistance, and low-temperature seal strength of the laminate 100 can be further improved.

[0123] Another preferred layer configuration for the laminate 100 is, for example, the layer configuration of the laminate 100 shown in Figure 3. That is, the laminate 100 preferably comprises a base layer (A3), a base layer (A1), a base layer (A2), an extruded resin layer (B), a polyethylene resin layer (C2), and an ionomer resin layer (C1) in this order. More preferably, each of the above layers is in contact with the others. With the above layer configuration, the balance of performance of the film impact strength, puncture strength, and other properties required for packaging materials of the laminate 100 can be further improved.

[0124] [Method for Manufacturing the Laminate] The method for manufacturing the laminate 100 is not particularly limited, but examples include the following manufacturing method. A film for the stretched base material layer (A) is produced by stretching a film obtained by co-extruding the resin compositions constituting each layer in the stretched base material layer (A). A film for the sealant layer (C) is produced by co-extruding the resin compositions constituting each layer in the sealant layer (C). Next, a resin composition constituting the extruded resin layer (B) is extruded so as to be positioned between the film for the stretched base material layer (A) and the film for the sealant layer (C), and the laminate 100 is produced by performing sandwich lamination.

[0125] [Applications of the laminate] The applications of the laminate 100 are not particularly limited, but for example, it can be used as a packaging material for packaging food, pharmaceuticals, industrial products, daily necessities, cosmetics, etc., and is preferably a laminate that can be used as a food packaging material.

[0126] [Packaging Material] The packaging material of this embodiment comprises a laminate 100. In this embodiment, the laminate 100 may be used in part of the packaging material, or the laminate 100 may be used throughout the entire packaging material.

[0127] The shape of the packaging material in this embodiment is not particularly limited, but examples include sheet-like, film-like, and bag-like shapes. The bag-like shape is not particularly limited, but examples include three-sided bags, four-sided bags, pillow bags, gusset bags, and stick bags. The packaging material in this embodiment is used for packaging food, pharmaceuticals, industrial products, daily necessities, cosmetics, etc., and is preferably a food packaging material.

[0128] [Packaging] The packaging of this embodiment comprises the packaging material of this embodiment and an article packaged by the packaging material. Examples of the article include food, pharmaceuticals, industrial products, daily necessities, cosmetics, etc., and is preferably food.

[0129] Although embodiments of the present invention have been described above, these are merely examples, and various other configurations can be adopted. Furthermore, the present invention is not limited to the embodiments described above, and any modifications, improvements, etc., that can achieve the objectives of the present invention are included in the present invention.

[0130] The embodiment will be described in detail below based on examples and comparative examples. However, this embodiment is not limited in any way to the descriptions of these examples.

[0131] First, we will describe the resin raw materials used in the examples and comparative examples.

[0132] <Resin> ・LLDPE1 (Linear low-density polyethylene, manufactured by Prime Polymer Co., Ltd., product name: Evolu SP2540, MFR: 3.8 g / 10 min, density: 924 kg / m³) ３) ・LLDPE2 (linear low-density polyethylene, manufactured by Prime Polymer Co., Ltd., product name: Evolu SP2320, MFR: 1.9 g / 10 min, density: 920 kg / m³) ３ ) ・HDPE (High-density polyethylene, manufactured by Prime Polymer Co., Ltd., product name: Hyzex 1300J, MFR: 13.0 g / 10 min, density: 960 kg / m³) ３ ) ・LDPE (Low-density polyethylene, manufactured by Mitsui Dow Polychemical Co., Ltd., MFR: 7.2 g / 10 min, density: 917 kg / m³) ３ ) ・EMAA (ethylene-methacrylic acid-isobutyl acrylate copolymer, manufactured by Mitsui Dow Polychemical Co., Ltd., content of constituent units derived from methacrylic acid: 4.0% by mass, content of constituent units derived from isobutyl acrylate: 7.5% by mass, MFR: 14.0 g / 10 min, density: 930 kg / m³ ３ ) ・IO1 (Ionomer of ethylene-methacrylic acid-isobutyl acrylate copolymer, manufactured by Mitsui Dow Polychemical Co., Ltd., content of constituent units derived from methacrylic acid: 10.0% by mass, content of constituent units derived from isobutyl acrylate: 10.0% by mass, metal ion: zinc, degree of neutralization: 70 mol%, MFR: 1.0 g / 10 min, density: 960 kg / m³) ３ ) ・IO2 (Ionomer of ethylene-methacrylic acid copolymer, manufactured by Mitsui Dow Polychemical Co., Ltd., content of constituent units derived from methacrylic acid: 15.0% by mass, metal ion: zinc, degree of neutralization: 23 mol%, MFR: 5.0 g / 10 min, density: 950 kg / m³) ３ )

[0133] The method for measuring the physical properties of the raw material resin is as follows:

[0134] <Melt Flow Rate (MFR)> The MFR of each resin was measured in accordance with JIS K7210:1999 under conditions of 190°C and 2160g load.

[0135] <Density> The density of each resin was measured in accordance with JIS K 7112:1999.

[0136] [Examples 1-5 and Comparative Example 1] <Preparation of film for stretched base material layer (A)> A 100 μm thick film was formed using a 3-type 3-layer T die-casting machine to have a layer configuration of "LLDPE1 / HDPE / LLDPE1". Then, it was stretched four times in the MD direction to obtain a uniaxially oriented film with a thickness of 25 μm as the film for stretched base material layer (A). The thickness of each layer of the film for stretched base material layer (A) is "LLDPE1 / HDPE / LLDPE1 = 5 μm / 15 μm / 5 μm".

[0137] <Film for Sealant Layer (C)> Using a three-layer inflation molding machine of three types, the films for sealant layer (C) of Examples 1 to 5 and Comparative Example 1 were molded to have the layer structure and layer thickness of sealant layer (C) as described in Table 1, at a processing temperature of 190°C. The single-layer films for Examples 2, 4 and Comparative Example 1 were obtained by extruding the resin raw materials described in Table 1 for all three layers. The multi-layer films for Examples 1, 3, and 5 were obtained by extruding the resins, with two layers being LLDPE2 and one layer being IO1.

[0138] <Preparation of Laminates> Using a 65 mmφ laminator, the film for the stretched substrate layer (A) was fed from the feed shaft, and the film for the sealant layer (C) was fed from the sandwich shaft so that the IO1 side (LLDPE2 side in Comparative Example 1) was facing outwards. The resin for the extruded resin layer (B) described in Table 1 was extruded from the extruder at a resin temperature of 310°C to a thickness of 15 μm, positioned between the film for the stretched substrate layer (A) and the film for the sealant layer (C). Sandwich lamination was performed at a processing speed of 80 m / min to obtain the laminates of Examples 1 to 5 and Comparative Example 1 (layer configuration: stretched substrate layer (A) / extruded resin layer (B) / sealant layer (C)). The thickness of each layer of the laminate is shown in Table 1.

[0139] [Measurement and Evaluation] The following measurements and evaluations were performed on the laminates of each example and comparative example. The results are shown in Table 1.

[0140] <Elmendorf Tear Strength> The Elmendorf tear strength in the MD direction of the laminates of each example and comparative example was measured in accordance with JIS K7128-2:1998.

[0141] <Film Impact Strength> In accordance with ASTM D3420, the film impact strength of the laminates in each example and comparative example was measured using a film impact tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.). The measured values ​​were converted to J / m per meter of thickness. The measurement conditions were as follows: Impact head: 1 / 2 Full scale: 15 kg Test environment: Temperature 23°C, humidity 50% RH

[0142] <Puncture Strength> In accordance with JIS Z1707:2019, the puncture strength of the laminates of each example and comparative example was measured using a precision universal testing machine (manufactured by Shimadzu Corporation, product name: Autograph AG-X) under the following conditions: temperature: 23°C, humidity: 50%RH, tip shape: 0.5R, diameter: 1 mm, test speed: 50 mm / min.

[0143] <Heat Seal Strength> (Measurement) Laminates of each example and comparative example were heat-sealed in the TD direction using a heat sealer (Tester Industries Co., Ltd., product name: TP701C Heat Seal Tester) with the sealant layer (C) surfaces in contact with each other, under the conditions of temperature: 110°C, sealing pressure (actual pressure): 0.2 MPa, time: 0.5 seconds, and sealing width: 10 mm, to obtain sheet samples. Test pieces were cut from the sheet samples in the MD direction with a width of 15 mm. The peel strength [N / 15 mm] obtained when the test piece was peeled in a T-shape in the MD direction at a tensile speed of 300 mm / min using a tensile testing machine (Shimadzu Corporation, product name: EZ-SX, 100N) in accordance with JIS Z1707:2019 was defined as the heat seal strength.

[0144] (Evaluation) The heat seal strength values ​​obtained in the above (measurement) were used to evaluate according to the following criteria: A: Heat seal strength is 10.0 N / 15 mm or higher B: Heat seal strength is less than 10.0 N / 15 mm

[0145]

[0146] This application claims priority based on Japanese Patent Application No. 2025-049462, filed on 25 March 2025, and incorporates all of its disclosures herein.

[0147] A Stretched base layer (A) B Extruded resin layer (B) C Sealant layer (C) A1 Base layer (A1) A2 Base layer (A2) A3 Base layer (A3) C1 Ionomer resin layer (C1) C2 Polyethylene resin layer (C2) 100 Laminate

Claims

1. A laminate comprising a stretched base material layer (A), an extruded resin layer (B), and a sealant layer (C) in this order, wherein the stretched base material layer (A) comprises a base material layer (A1) containing high-density polyethylene (a1) and a base material layer (A2) containing linear low-density polyethylene (a2), the base material layer (A2) containing linear low-density polyethylene (a2) is located on one side of the base material layer (A1) containing high-density polyethylene (a1), the base material layer (A2) containing linear low-density polyethylene (a2) is in contact with the extruded resin layer (B), the sealant layer (C) comprises an ionomer resin layer (C1) containing an ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer, and the ionomer resin layer (C1) is located at least on the surface side of the laminate in the sealant layer (C), A laminate in which the content of the ionomer (c1) of an ethylene-unsaturated carboxylic acid copolymer in the ionomer resin layer (C1) is 80% by mass or more, when the total amount of the ionomer resin layer (C1) is considered to be 100% by mass.

2. The laminate according to claim 1, wherein the stretched base material layer (A) further comprises a base material layer (A3) containing linear low-density polyethylene (a3), and the base material layer (A3) containing linear low-density polyethylene (a3) ​​is located on the side of the base material layer (A1) containing high-density polyethylene (a1) that is opposite to the one side.

3. The laminate according to claim 1 or 2, wherein the extruded resin layer (B) contains low-density polyethylene (b1).

4. The laminate according to any one of claims 1 to 3, wherein the extruded resin layer (B) comprises at least one selected from the group consisting of ethylene-unsaturated carboxylic acid copolymers (b2) and ionomers (b3) of ethylene-unsaturated carboxylic acid copolymers.

5. The laminate according to any one of claims 1 to 4, wherein the sealant layer (C) is made of the ionomer resin layer (C1).

6. The laminate according to any one of claims 1 to 4, wherein the sealant layer (C) further comprises a polyethylene resin layer (C2), and the polyethylene resin layer (C2) is in contact with the extruded resin layer (B).

7. The laminate according to claim 6, wherein the polyethylene resin layer (C2) comprises a composition containing at least one selected from the group consisting of linear low-density polyethylene and low-density polyethylene.

8. A packaging material comprising a laminate according to any one of claims 1 to 7.

9. A packaging body comprising the packaging material described in claim 8 and an article packaged by the packaging material.

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