Laminates and packaging

Abstract

The present invention provides a laminate capable of improving heat seal strength and a packaging body with improved heat seal strength. [Solution] A laminate 100 comprising, in this order, a base layer 10, a resin layer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, and a sealant resin layer (B) containing a cyclic olefin resin, wherein the sealant resin layer (B) is the surface layer of the laminate 100.

Description

[Technical Field]

[0001] This invention relates to laminates and packaging. [Background technology]

[0002] As for technologies related to laminates and packaging, for example, the technology described in Patent Document 1 is known.

[0003] Patent Document 1 describes a laminated film consisting of three layers: a seal layer, an intermediate layer, and a bonding layer. The seal layer is made of a layer of an ethylene-unsaturated carboxylic acid copolymer ionomer composition, in which 0.4 to 2.0% by weight of a slip agent and 0.5 to 10.0% by weight of an antiblocking agent are blended with the total amount of the ethylene-unsaturated carboxylic acid copolymer ionomer, slip agent, and antiblocking agent. The intermediate layer is made of a slip agent in the range of 0.01 to 0.5% by weight relative to the total amount of the ethylene-unsaturated carboxylic acid copolymer or its ionomer and the slip agent. The present invention describes a laminated film comprising a layer of a composition of an ethylene-unsaturated carboxylic acid copolymer or its ionomer (provided that the slip agent concentration in the intermediate layer composition is lower than the slip agent concentration in the ionomer composition of the sealing layer), wherein the laminating layer comprises a layer of an ethylene-unsaturated carboxylic acid copolymer ionomer composition that contains 0.5 to 10.0% by weight of an antiblocking agent relative to the total amount of the ethylene-unsaturated carboxylic acid copolymer ionomer and the antiblocking agent, and does not contain a slip agent. Patent Document 1 describes how it is possible to provide a laminated film in which the bonding layer to be bonded to the adhesive surface of the substrate layer has a high wettability and good adhesive affinity, the sliding friction coefficient of the sealing layer is low and has excellent antiblocking properties, and moreover, the adhesion between each layer is strong and there is no delamination between layers. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2009-291973 [Overview of the project] [Problems that the invention aims to solve]

[0005] The present invention provides a laminate capable of improving heat seal strength and a packaging body with improved heat seal strength. [Means for solving the problem]

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

[0007] [1] A base layer and A resin layer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, A laminate comprising a sealant resin layer (B) containing a cyclic olefin resin, in this order, A laminate in which the sealant resin layer (B) is the surface layer of the laminate. [2] The laminate according to [1], wherein the thickness of the resin layer (A) is 2 or more and 10 or less, when the thickness of the sealant resin layer (B) is 1. [3] A barrier layer is provided between the substrate layer and the resin layer (A), The laminate according to [1] or [2], wherein the barrier layer is in contact with the resin layer (A). [4] The laminate according to [3], further comprising an adhesive resin layer between the base material layer and the barrier layer. [5] A laminate according to any one of [1] to [4], wherein the thermal deflection temperature of the cyclic olefin resin, measured under a bending stress of 1.82 MPa in accordance with ASTM D648, is 60°C or more and 200°C or less. [6] The content of unsaturated carboxylic acid-derived constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 1% by mass or more and 15% by mass or less, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is taken as 100% by mass. The laminate according to any one of [1] to [5], wherein the content of constituent units derived from unsaturated carboxylic acid esters in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 1% by mass or more and 15% by mass or less, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 100% by mass. [7] A laminate according to any one of [1] to [6] above, wherein the melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, measured under conditions of 190°C and a 2160g load in accordance with JIS K7210:1999, is 2.0g / 10min or more and 30g / 10min or less. [8] The laminate according to any one of [1] to [7], wherein the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer comprises one or more 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. [9] A packaging body comprising the laminate described in any of the above [1] to [8]. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a laminate capable of improving heat seal strength and a packaging body with improved heat seal strength. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing an example of the structure of the laminate according to this embodiment. [Figure 2] This is a cross-sectional view schematically showing an example of the structure of the laminate of the present embodiment.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic and do not match the actual dimensional ratios. The numerical range "A to B" represents A or more and B or less unless otherwise specified. In this specification, the resin layer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer may be abbreviated as the resin layer (A). Further, the sealant resin layer (B) containing a cyclic olefin-based resin may be abbreviated as the sealant resin layer (B) or the resin layer (B). Further, (meth)acryl represents a concept encompassing both acryl and methacryl.

[0011] [Laminate] FIG. 1 and FIG. 2 are cross-sectional views schematically showing an example of the structure of the laminate 100 of the present embodiment. The laminate 100 is a laminate including a base material layer 10, a resin layer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, and a sealant resin layer (B) containing a cyclic olefin-based resin, in this order, and the sealant resin layer (B) is the surface layer of the laminate 100.

[0012] Hereinafter, each layer will be specifically described.

[0013] [Base Material Layer] The laminate 100 includes a base material layer 10. The base material layer 10 is at least one selected from the group consisting of, for example, a resin film, a resin sheet, and paper, and is preferably a resin film.

[0014] The resin constituting the resin film of this embodiment includes, for example, one or more selected from the group consisting of polyolefins (polyethylene, polypropylene, poly-4-methyl-1-pentene, polybutene, etc.), polyesters (polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamides (nylon-6, nylon-66, polymetaxylene adipamide, etc.), polyvinyl chloride, polyimide, ethylene-vinyl acetate copolymer or its saponified product, cellulose, polyvinyl alcohol, polyacrylonitrile, polycarbonate, polystyrene, ionomer, etc., and preferably includes one or more selected from the group consisting of polypropylene, polyethylene terephthalate, and polyamide, and more preferably includes polyethylene terephthalate.

[0015] The resin film in this embodiment may be an unstretched film or a stretched film, but from the viewpoint of further improving the strength of the laminate 100, it is preferably a stretched film, and more preferably a biaxially oriented film.

[0016] The resin film of this embodiment is preferably a biaxially oriented polyester film, and more preferably a biaxially oriented polyethylene terephthalate film.

[0017] The resin film of this embodiment may be surface-treated (for example, corona treatment).

[0018] The thickness of the substrate layer 10 is preferably 1 μm or more and 50 μm or less, more preferably 3 μm or more and 30 μm or less, and even more preferably 5 μm or more and 20 μm or less.

[0019] <Resin layer (A)> The laminate 100 comprises a resin layer (A) containing an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer.

[0020] The ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment includes, for example, one or more selected from the group consisting of block copolymers, random copolymers, and graft copolymers, and from the viewpoint of improving the productivity of the laminate 100, it includes one or more selected from the group consisting of random copolymers and graft copolymers of random copolymers, and preferably includes random copolymers.

[0021] In the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment, the unsaturated carboxylic acid includes, for example, an unsaturated carboxylic acid having 3 to 8 carbon atoms and its half-ester. 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 (such as monomethyl maleic acid and monoethyl maleic acid). From the viewpoint of further improving the heat seal strength in the laminate 100, it preferably includes one or more selected from the group consisting of acrylic acid and methacrylic acid, and more preferably includes methacrylic acid.

[0022] In the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment, the unsaturated carboxylic acid ester includes, for example, one or more selected from the group consisting of alkyl (meth)acrylates and alkyl maleates, preferably including alkyl (meth)acrylates, more preferably including alkyl (meth)acrylates having 1 to 6 carbon atoms in the alkyl moiety, and even more preferably including alkyl (meth)acrylates having 1 to 4 carbon atoms in the alkyl moiety.

[0023] The alkyl (meth)acrylate 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. From the viewpoint of further improving the heat seal strength in the laminate 100, it preferably includes at least one selected from the group consisting of isobutyl acrylate and isobutyl methacrylate, and more preferably includes isobutyl acrylate.

[0024] The alkyl maleate includes, for example, at least one selected from the group consisting of dimethyl maleate and diethyl maleate.

[0025] The ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment preferably comprises one or more 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.

[0026] The content of ethylene-derived constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment is preferably 70% to 98% by mass, more preferably 78% to 96% by mass, and 85% to 94% by mass, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is taken as 100% by mass.

[0027] In this embodiment, the content of unsaturated carboxylic acid-derived constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer 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-unsaturated carboxylic acid ester copolymer is 100% by mass, from the viewpoint of further improving the heat seal strength in the laminate 100.

[0028] In this embodiment, the content of constituent units derived from unsaturated carboxylic acid esters in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is preferably 1% by mass or more and 15% by mass or less, more preferably 3% by mass or more and 12% by mass or less, and even more preferably 5% by mass or more and 10% by mass or less, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 100% by mass, from the viewpoint of further improving the heat seal strength in the laminate 100.

[0029] The content of constituent units derived from unsaturated carboxylic acids and unsaturated carboxylic acid esters in ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0030] The melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer in this embodiment is preferably 2.0 g / 10 min to 30 g / 10 min, more preferably 5.0 g / 10 min to 25 g / 10 min, and even more preferably 10 g / 10 min to 20 g / 10 min. The melt flow rate (MFR) of an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is the value measured under conditions of 190°C and a 2160g load, in accordance with JIS K7210:1999.

[0031] The density of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer in this embodiment is preferably 800 kg / m³. 3More 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 ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers refers to the value measured in accordance with JIS K 7112:1999.

[0032] The method for producing the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer of this embodiment is not particularly limited and can be produced by known methods, for example.

[0033] The content of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer in the resin layer (A) 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 resin layer (A) is considered to be 100% by mass, from the viewpoint of further improving the heat seal strength in the laminate 100.

[0034] The resin layer (A) may contain other components besides the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer. Other components include, for example, one or more selected from the group consisting of plasticizers, antioxidants, UV absorbers, antistatic agents, surfactants, colorants, light stabilizers, foaming agents, lubricants, crystal nucleating agents, crystallization accelerators, crystallization retardants, catalyst deactivators, inorganic fillers, organic fillers, impact 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, dispersants, and resins other than ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers (e.g., thermoplastic resins and thermosetting resins).

[0035] The thickness of the resin layer (A) is preferably 10 μm or more and 50 μm or less, more preferably 12 μm or more and 40 μm or less, and even more preferably 15 μm or more and 30 μm or less.

[0036] The thickness of the resin layer (A) is preferably 2 to 10, more preferably 3 to 8, even more preferably 3.5 to 6.5, and even more preferably 4 to 6, when the thickness of the sealant resin layer (B) is set to 1.

[0037] <Sealant resin layer (B)> The laminate 100 comprises a sealant resin layer (B) containing a cyclic olefin resin. The sealant resin layer (B) is the surface layer of the laminate 100. The sealant resin layer (B) is preferably in contact with the resin layer (A).

[0038] The cyclic olefin resin in this embodiment is not particularly limited as long as it is a resin containing constituent units derived from cyclic olefins, and may be a homopolymer (cyclic olefin homopolymer) or a copolymer (cyclic olefin copolymer). The cyclic olefin resin of this embodiment preferably includes a cyclic olefin copolymer.

[0039] The cyclic olefin copolymer preferably includes a copolymer of a cyclic olefin and an α-olefin, more preferably a copolymer of a cyclic olefin and an α-olefin having 2 to 10 carbon atoms, still more preferably a copolymer of a cyclic olefin and an α-olefin having 2 to 5 carbon atoms, and still more preferably a copolymer of a cyclic olefin and ethylene.

[0040] The heat deflection temperature under load of the cyclic olefin resin of the present embodiment is preferably 60°C or higher and 200°C or lower, more preferably 65°C or higher and 120°C or lower, and still more preferably 68°C or higher and 80°C or lower. The heat deflection temperature under load of the cyclic olefin resin means the value measured under the condition of a bending stress of 1.82 MPa in accordance with ASTM D648.

[0041] The melt flow rate (MFR) of the cyclic olefin resin of the present embodiment is preferably 5.0 g / 10 min or more and 50 g / 10 min or less, more preferably 10 g / 10 min or more and 45 g / 10 min or less, and still more preferably 20 g / 10 min or more and 40 g / 10 min or less. The melt flow rate (MFR) of the cyclic olefin resin means the value measured under the conditions of 260°C and a load of 2160 g in accordance with JIS K7210:1999.

[0042] The density of the cyclic olefin resin of the present embodiment is preferably 900 kg / m 3 or more and 1150 kg / m 3 or less, more preferably 950 kg / m 3 or more and 1100 kg / m 3 or less, still more preferably 1000 kg / m 3 or more and 1050 kg / m 3 or less. The density of the cyclic olefin resin means the value measured in accordance with ASTM D792.

[0043] The method for producing the cyclic olefin resin of the present embodiment is not particularly limited, and for example, it can be produced by a known method. The cyclic olefin resin in this embodiment may be, for example, a commercially available cyclic olefin resin. Examples of commercially available cyclic olefin resins include Apel (manufactured by Mitsui Chemicals, Inc.).

[0044] The content of cyclic olefin resin in the sealant 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 sealant resin layer (B) is considered as 100% by mass, from the viewpoint of further improving the heat seal strength in the laminate 100.

[0045] The sealant resin layer (B) may contain components other than cyclic olefin resins. Other components include, for example, one or more selected from the group consisting of lubricants, antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, antiblocking agents, flame retardants, crosslinking agents, and colorants.

[0046] The thickness of the sealant resin layer (B) is preferably 1 μm to 20 μm, more preferably 2 μm to 15 μm, and even more preferably 3 μm to 10 μm.

[0047] <Barrier layer> From the viewpoint of suppressing the oxygen permeability of the laminate 100, the laminate 100 preferably further comprises a barrier layer 20. The laminate 100 more preferably includes a barrier layer 20 between the base layer 10 and the resin layer (A), with the barrier layer 20 in contact with the resin layer (A).

[0048] The barrier layer 20 is at least one selected from the group consisting of, for example, aluminum foil, aluminum vapor-deposited film, and transparent vapor-deposited film, and is preferably aluminum foil.

[0049] Aluminum-deposited film is a film in which an aluminum layer is deposited onto a resin film. For example, the resin film in the aluminum vapor-deposited film can be the same type of film as the resin film in the substrate layer 10.

[0050] A transparent vapor-deposited film is a film in which an inorganic oxide thin film is formed on a resin film. The inorganic oxide thin film can be formed by methods such as vacuum deposition or sputtering. For example, the resin film in the transparent vapor-deposited film can be the same type of film as the resin film in the substrate layer 10. The inorganic oxide thin film in the transparent vapor-deposited film includes, for example, at least one selected from the group consisting of silicon dioxide, aluminum oxide, and magnesium oxide.

[0051] The thickness of the barrier layer 20 is preferably 1 μm to 20 μm, more preferably 3 μm to 15 μm, and even more preferably 5 μm to 10 μm, from the viewpoint of suppressing the oxygen permeability of the laminate 100.

[0052] <Adhesive resin layer> The laminate 100 preferably further comprises an adhesive resin layer 30. The laminate 100 more preferably further comprises an adhesive resin layer 30 between the base layer 10 and the barrier layer 20.

[0053] The adhesive resin layer 30 includes, for example, polyolefin. The polyolefin includes, for example, at least one selected from the group consisting of low-density polyethylene and linear low-density polyethylene, and preferably includes low-density polyethylene.

[0054] The thickness of the adhesive resin layer 30 is preferably 1 μm or more and 30 μm or less, more preferably 5 μm or more and 25 μm or less, and even more preferably 10 μm or more and 20 μm or less.

[0055] <Other layers> The laminate 100 may further comprise other layers. The other layers include, for example, one or more selected from the group consisting of an anchor coat layer, an anti-reflective layer, an anti-fouling layer, and a foamed layer.

[0056] The laminate 100 preferably further comprises an anchor coat layer. The laminate 100 more preferably comprises an anchor coat layer between the base layer 10 and the barrier layer 20, and even more preferably comprises an anchor coat layer between the base layer 10 and the adhesive resin layer 30.

[0057] The anchor coat layer in this embodiment is a layer containing an anchor coat agent. For the anchor coating agent, commercially available anchor coating agents can be used, for example. Examples of commercially available anchor coating agents include Seikadine (manufactured by Dainichi Seika Kogyo Co., Ltd.).

[0058] The laminate 100 comprises a base layer 10, a resin layer (A), and a sealant resin layer (B) in that order, with the sealant resin layer (B) being the surface layer of the laminate. The laminate 100 preferably comprises a base layer 10, a barrier layer 20, a resin layer (A), and a sealant resin layer (B) in this order, with the sealant resin layer (B) being the surface layer of the laminate. More preferably, it comprises a base layer 10, an anchor coat layer, a barrier layer 20, a resin layer (A), and a sealant resin layer (B) in this order, with the sealant resin layer (B) being the surface layer of the laminate. Even more preferably, it comprises a base layer 10, an adhesive resin layer 30, a barrier layer 20, a resin layer (A), and a sealant resin layer (B) in this order, with the sealant resin layer (B) being the surface layer of the laminate. Even more preferably, it comprises a base layer 10, an anchor coat layer, an adhesive resin layer 30, a barrier layer 20, a resin layer (A), and a sealant resin layer (B) in this order, with the sealant resin layer (B) being the surface layer of the laminate.

[0059] The thickness of the laminate 100 is preferably 10 μm or more and 100 μm or less, more preferably 25 μm or more and 80 μm or less, and even more preferably 50 μm or more and 70 μm or less.

[0060] [Method for manufacturing laminates] The method for manufacturing the laminate 100 is not particularly limited, but examples include a method of co-extruding a resin layer (A) and a sealant resin layer (B) onto a laminate including a base layer 10.

[0061] [Applications of laminates] The use of the laminate 100 is not particularly limited, but it can be suitably used as a packaging material for packaging food, pharmaceuticals, industrial products, daily necessities, cosmetics, etc.

[0062] [Packaging] The packaging body of this embodiment comprises a laminate 100. In this embodiment, the packaging preferably has the sealant resin layer (B) located on the side that contains the contents.

[0063] The packaging of this embodiment may be a bag-shaped packaging, and may also be a packaging that includes a container having an opening and a lid material that closes the opening.

[0064] The bag-shaped packaging can be manufactured, for example, by folding the laminate 100 itself and sealing it on three sides, or by sealing two laminates 100 on all four sides.

[0065] In this embodiment, if the packaging includes a container having an opening and a lid material that closes the opening, the lid material preferably includes a laminate 100.

[0066] [Packaged goods] The packaged article of this embodiment includes the packaging body of this embodiment and the contents contained within the packaging body. The contents include, for example, at least one selected from the group consisting of food, pharmaceuticals, industrial products, daily necessities, and cosmetics.

[0067] The embodiments of the present invention have been described above, but these are merely examples, and various other configurations can also 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. [Examples]

[0068] 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.

[0069] First, we will describe the raw materials used in the examples and comparative examples.

[0070] [Raw materials] <Resin> EMAA1 (Ethylene-methacrylic acid-isobutyl acrylate copolymer, methacrylic acid-derived component content: 4.0% by mass, isobutyl acrylate-derived component content: 7.5% by mass, MFR: 14g / 10min, Density: 930kg / m³) 3 ) • EMAA2 (ethylene-methacrylic acid copolymer, methacrylic acid-derived component content: 9.0% by mass, MFR: 9g / 10 min, density: 930 kg / m³) 3 ) • LDPE (Large-density polyethylene, manufactured by Mitsui Dow Polychemical Co., Ltd., product name: Mirason 11P, MFR: 7.2g / 10min, density: 920kg / m³) 3 ) • Cyclic olefin resin (manufactured by Mitsui Chemicals, Inc., product name: APL6509T, MFR: 30g / 10min, density: 1020kg / m³) 3 (Temperature deflection temperature under load: 70°C)

[0071] The method for measuring the physical properties of the raw material resin is as follows:

[0072] <Measuring Melt Flow Rate (MFR)> The MFRs of EMAA1, EMAA2, and LDPE were measured in accordance with JIS K7210:1999 under conditions of 190°C and a 2160g load. The MFR of the cyclic olefin resin was measured in accordance with JIS K7210:1999 under conditions of 260°C and 2160g load.

[0073] <Density Measurement> The densities of EMAA1, EMAA2, and LDPE were measured in accordance with JIS K 7112:1999. The density of the cyclic olefin resin was measured in accordance with ASTM D792.

[0074] <Measurement of thermal deflection temperature under load> The thermal deflection temperature under load of the cyclic olefin resin was measured in accordance with ASTM D648 under a bending stress of 1.82 MPa.

[0075] <Base material> • PET film (manufactured by Toray Industries, Inc., product name: Lumirror S10, thickness: 12 μm) • Aluminum foil (manufactured by Toyo Aluminum Co., Ltd., product name: 1N30, thickness: 7μm)

[0076] [Example 1] <Fabrication of laminate (a)> Using an extrusion laminator with a 65mmφ extruder (L / D=28), an anchor coating agent (manufactured by Dainichi Seika Kogyo Co., Ltd., product name: Seikadine 2710A + Seikadine 2710C, solid concentration: 7% by mass) was applied to the corona-treated surface of the PET film at a rate of 2g / cm². 2The coating was applied under wet conditions. Next, LDPE was extruded onto the coated surface of the anchor coating agent to a thickness of 15 μm under the following processing conditions: die outlet resin temperature: 320°C, air gap: 120 mm, processing speed: 120 m / min, and processing width: 500 mm, thereby forming an LDPE layer as an adhesive resin layer. Aluminum foil was laid on the opposite side of the LDPE layer from the PET film to create laminate (a). The layer structure of laminate (a) is "PET film layer (thickness: 12 μm) / anchor coating layer / LDPE layer (thickness: 15 μm) / aluminum foil layer (thickness: 7 μm)".

[0077] <Fabrication of the laminate in Example 1> Using an extrusion laminator with a 65mmφ extruder (L / D=28), EMAA1 was used as resin layer (A) and a cyclic olefin resin as resin layer (B) were extruded onto the aluminum foil surface of the laminate (a) under the following processing conditions: die outlet resin temperature: 310℃, air gap: 120mm, processing speed: 120m / min, and processing width: 500mm, so that the thickness of resin layer (A) / the thickness of resin layer (B) = 20μm / 5μm, thereby forming the laminate of Example 1. The layer configuration of the laminate of Example 1 is "PET film layer (thickness: 12μm) / anchor coat layer / LDPE layer (thickness: 15μm) / aluminum foil layer (thickness: 7μm) / resin layer (A) (thickness: 20μm) / resin layer (B) (thickness: 5μm)".

[0078] [Comparative Example 1] In Example 1, the laminate of Comparative Example 1 was obtained by the same method as in Example 1, except that EMAA2 was used as the resin layer (A) and the die exit resin temperature was set to 300°C.

[0079] [Adhesion evaluation] The laminate obtained above, with the resin layer (B) surfaces in contact with each other, was subjected to a gauge pressure of 3.0 kg / cm² using a heat sealer (product name: manufactured by Tester Sangyo Co., Ltd.). 2A sheet sample (140°C) was obtained by heat sealing in the TD direction under the following conditions: seal width: 10 mm, seal time: 0.5 seconds, temperature: 140°C. Similarly, a sheet sample (160°C) was obtained by heat sealing the laminate under the same conditions except that the temperature was 160°C. Test specimens were prepared by cutting sheet samples (140°C) and sheet samples (160°C) in the MD direction to a length of 100 mm and a width of 15 mm. For each test specimen, the peel strength [N / 15mm] was measured in accordance with JIS Z 1707:2019, using a tensile testing machine (Shimadzu Corporation, product name: EZ-SX, 100N) at a speed of 300 mm / min and under T-type peeling conditions, when peeled in the MD direction. Adhesion was evaluated based on the following evaluation criteria. A: Peel strength of 10N / 15mm or more B: Peel strength of 5N / 15mm or more and less than 10N / 15mm C: Peel strength less than 5N / 15mm

[0080] Table 1 shows the evaluation results for the adhesion properties of Example 1 and Comparative Example 1. In Table 1, "Adhesion Evaluation (140°C)" refers to the evaluation results for test specimens of the sheet sample (140°C), and "Adhesion Evaluation (160°C)" refers to the evaluation results for test specimens of the sheet sample (160°C).

[0081] [Table 1]

[0082] Table 1 shows that the laminates of the examples exhibited good adhesion. In other words, the present invention provides laminates capable of improving heat seal strength and packaging with improved heat seal strength. [Explanation of Symbols]

[0083] A Resin layer (A) B. Sealant resin layer (B) 10 Base material layer 20 Barrier layer 30 Adhesive resin layer 100-layer structure

Claims

1. A base layer and A resin layer (A) containing ethylene, unsaturated carboxylic acid, and unsaturated carboxylic acid ester copolymer, A laminate comprising a sealant resin layer (B) containing a cyclic olefin resin, in this order, A laminate in which the sealant resin layer (B) is the surface layer of the laminate.

2. The laminate according to claim 1, wherein the thickness of the resin layer (A) is 2 or more and 10 or less, when the thickness of the sealant resin layer (B) is 1.

3. A barrier layer is provided between the substrate layer and the resin layer (A), The laminate according to claim 1, wherein the barrier layer is in contact with the resin layer (A).

4. The laminate according to claim 3, further comprising an adhesive resin layer between the base material layer and the barrier layer.

5. The laminate according to claim 1, wherein the thermal deflection temperature of the cyclic olefin resin, measured under a bending stress of 1.82 MPa in accordance with ASTM D648, is 60°C or more and 200°C or less.

6. The content of unsaturated carboxylic acid-derived constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 1% by mass or more and 15% by mass or less, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is taken as 100% by mass. The laminate according to claim 1, wherein the content of constituent units derived from unsaturated carboxylic acid esters in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 1% by mass or more and 15% by mass or less, when the total amount of constituent units in the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer is 100% by mass.

7. The laminate according to claim 1, wherein the melt flow rate (MFR) of the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, measured in accordance with JIS K7210:1999 under conditions of 190°C and a 2160g load, is 2.0 g / 10 min or more and 30 g / 10 min or less.

8. The laminate according to claim 1, wherein the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer comprises one or more 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.

9. A packaging body comprising the laminate according to any one of claims 1 to 8.

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