Stretched substrate, barrier substrate, laminate and packaging container

Abstract

To provide a polyethylene-based stretched substrate with superior gas barrier properties.SOLUTION: A stretched substrate comprises at least a first surface resin layer primarily composed of gas barrier resin, one or more polyethylene intermediate layers primarily composed of polyethylene, and a second surface resin layer primarily composed of gas barrier resin, in the stated order. In at least one polyethylene intermediate layer, the polyethylene includes at least one polyethylene selected from high-density polyethylene and medium-density polyethylene, or has a density of more than 0.930 g / cm3 to 0.960 g / cm3 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to stretched substrates, barrier substrates, laminates, and packaging containers. [Background technology]

[0002] Packaging containers are used to store contents such as liquids and powders. Packaging containers are made using a laminate including a substrate and a heat seal layer (see, for example, Patent Document 1). For example, a stretched polyethylene film is used as the substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-55156 A Summary of the Invention [Problem to be solved by the invention]

[0004] Depending on the type of contents, the packaging container may be required to have gas barrier properties. Stretched polyethylene films usually do not have high gas barrier properties. An object of the present disclosure is to provide a polyethylene-based stretched substrate having excellent gas barrier properties. An object of the present disclosure is to provide a polyethylene-based stretched substrate that can be suitably used to prepare a barrier substrate having excellent gas barrier properties. [Means for solving the problem]

[0005] The stretched substrate according to one embodiment of the present disclosure comprises at least a first surface resin layer containing a gas barrier resin as a main component, one or more polyethylene intermediate layers containing polyethylene as a main component, and a second surface resin layer containing a gas barrier resin as a main component, in this order, and the polyethylene in at least one layer of the polyethylene intermediate layer contains at least one type of polyethylene selected from high density polyethylene and medium density polyethylene, or has a viscosity of 0.930 g / cm 3 Super 0.960g / cm 3 It has the following density: The stretched substrate according to one embodiment of the present disclosure comprises, in this order, at least a first surface resin layer containing polyethylene and an adhesive resin, one or more polyethylene intermediate layers containing polyethylene as a main component, and a second surface resin layer containing polyethylene and an adhesive resin, and the polyethylene in at least one layer selected from the first surface resin layer, the polyethylene intermediate layer, and the second surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or has a viscosity of 0.930 g / cm 3 Super 0.960g / cm 3 It has the following density: Effect of the Invention

[0006] According to the present disclosure, a polyethylene-based stretched substrate having excellent gas barrier properties can be provided. Also, according to the present disclosure, a polyethylene-based stretched substrate that can be suitably used for producing a barrier substrate having excellent gas barrier properties can be provided. For example, a barrier substrate having a vapor deposition film on the polyethylene-based stretched substrate has even better gas barrier properties. The stretched substrate and the barrier substrate are useful, for example, as a substrate in a packaging material for producing a packaging container having excellent gas barrier properties. [Brief description of the drawings]

[0007] [Figure 1A] FIG. 1A is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 1B]FIG. 1B is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 2A] FIG. 2A is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 2B] FIG. 2B is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 2C] FIG. 2C is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 2D] FIG. 2D is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 2E] FIG. 2E is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 3A] FIG. 3A is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 3B] FIG. 3B is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 3C] FIG. 3C is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 3D] FIG. 3D is a schematic cross-sectional view showing one embodiment of a barrier substrate. [Figure 4A] FIG. 4A is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 4B] FIG. 4B is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 5A] FIG. 5A is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 5B] FIG. 5B is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 6A] FIG. 6A is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 6B] FIG. 6B is a schematic cross-sectional view showing one embodiment of a laminate. [Figure 7] FIG. 7 is a perspective view showing an embodiment of a tube container including a tube container body including a laminate and a cap. [Figure 8] FIG. 8 is a cross-sectional view taken along line AA in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments of the present disclosure will be described in detail. The present disclosure can be implemented in many different forms, and is not to be interpreted as being limited to the description of the embodiments exemplified below. In the drawings, the width, thickness, shape, etc. of each layer may be shown diagrammatically in order to make the explanation clearer, but these are merely examples and do not limit the interpretation of the present disclosure. In this specification and each figure, elements similar to those already explained with respect to the previous figures are given the same reference numerals, and detailed explanations may be omitted as appropriate.

[0009] In this specification, when multiple upper limit candidates and multiple lower limit candidates are listed for a certain parameter, the numerical range of the parameter may be configured by combining any one of the upper limit candidates and any one of the lower limit candidates. Examples of the above parameters include physical property values, content ratios of components, and layer thicknesses. As an example, the description "Parameter B is preferably A1 or more, more preferably A2 or more, and even more preferably A3 or more. Parameter B is preferably A4 or less, more preferably A5 or less, and even more preferably A6 or less." will be explained. In this example, the numerical range of parameter B may be A1 or more and A4 or less, A1 or more and A5 or less, A1 or more and A6 or less, A2 or more and A4 or less, A2 or more and A5 or less, A2 or more and A6 or less, A3 or more and A4 or less, A3 or more and A5 or less, or A3 or more and A6 or less.

[0010] In this specification, polyethylene refers to a polymer in which the content of ethylene-derived structural units in all repeating structural units exceeds 50 mol%. In this polymer, the content of ethylene-derived structural units is preferably 70 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, and particularly preferably 95 mol% or more. The content is measured by NMR.

[0011] In this specification, polyethylene may be a homopolymer of ethylene, or a copolymer of ethylene and an ethylenically unsaturated monomer other than ethylene. Examples of the ethylenically unsaturated monomer other than ethylene include α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 4-methyl-1-pentene, and 6-methyl-1-heptene, vinyl monomers such as vinyl acetate and vinyl propionate, and (meth)acrylic acid esters such as methyl (meth)acrylate and ethyl (meth)acrylate.

[0012] In this specification, examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, as well as ethylene-vinyl acetate copolymer and ethylene-(meth)acrylic acid ester copolymer. From the viewpoint of reducing the environmental load, polyethylene derived from biomass or polyethylene that has been mechanically recycled or chemically recycled may be used as the polyethylene.

[0013] In this specification, the density of polyethylene is as follows: The density of the high density polyethylene is preferably 0.945 g / cm 3 The upper density limit of high density polyethylene is, for example, 0.965 g / cm 3 and preferably 0.960 g / cm 3 The density of the medium density polyethylene is preferably 0.930 g / cm 3 Exceeds 0.945g / cm 3 The density of the low density polyethylene is preferably 0.860 g / cm 3 More than 0.930g / cm 3 Less than or equal to 0.900 g / cm 3 More than 0.930g / cm 3 The density of the linear low density polyethylene is preferably 0.860 g / cm3 More than 0.930g / cm 3 Less than or equal to 0.900 g / cm 3 More than 0.930g / cm 3 In this specification, the density of polyethylene is measured in accordance with JIS K7112:1999, Method D (density gradient tube method, 23° C.).

[0014] Low-density polyethylene is, for example, polyethylene obtained by polymerizing ethylene by high-pressure polymerization (high-pressure low-density polyethylene). Linear low-density polyethylene is, for example, polyethylene obtained by polymerizing ethylene and a small amount of α-olefins by a polymerization method using a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst.

[0015] Polyethylenes with different densities or branches can be obtained by appropriately selecting a polymerization method. For example, it is preferable to carry out polymerization in one or more stages by using a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst as a polymerization catalyst, by any of gas phase polymerization, slurry polymerization, solution polymerization, and high pressure ion polymerization.

[0016] In this specification, the melt flow rate (MFR) of polyethylene is preferably 0.1 g / 10 min or more, more preferably 1 g / 10 min or more, even more preferably 1.5 g / 10 min or more, and preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, even more preferably 10 g / 10 min or less, particularly preferably 5 g / 10 min or less, for example, 0.1 g / 10 min or more and 50 g / 10 min or less, from the viewpoint of film-forming property and processability. In this specification, the MFR of polyethylene is measured by the A method at a temperature of 190° C. and a load of 2.16 kg in accordance with JIS K7210-1:2014.

[0017] In this specification, each of the components (e.g., polyolefins such as polyethylene, α-olefins, resin materials such as gas barrier resins, adhesive resins, and additives) appearing in the following description may be used either alone or in combination of two or more types.

[0018] In this specification, although "film" and "sheet" may be referred to, the "film" and the "sheet" are not distinguished from each other solely on the basis of the difference in name.

[0019] In this specification, the "main component" of a certain layer refers to a component whose content in the layer is more than 50% by mass, preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more.

[0020] [Stretched base material] The stretched substrate of the first aspect of the present disclosure comprises: a first surface resin layer containing a gas barrier resin as a main component; A polyethylene intermediate layer containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component; In the thickness direction, at least Hereinafter, "provided in this order in the thickness direction" will also be simply expressed as "provided in this order."

[0021] The stretched substrate of the second aspect of the present disclosure comprises: A first surface resin layer containing polyethylene and an adhesive resin; A polyethylene intermediate layer containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component; In the thickness direction, at least

[0022] The stretched substrate of the third aspect of the present disclosure comprises: A first surface resin layer containing polyethylene and an adhesive resin; A polyethylene intermediate layer containing polyethylene as a main component; a second surface resin layer containing polyethylene and an adhesive resin; In the thickness direction, at least

[0023] The stretched substrate according to the fourth aspect of the present disclosure comprises: A first surface resin layer containing polyethylene as a main component; A polyethylene intermediate layer containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component or containing polyethylene and an adhesive resin; In the thickness direction, at least The stretched substrate of the fourth embodiment in which the second surface resin layer contains a gas barrier resin as a main component is also referred to as the "stretched substrate of the fourth embodiment." The stretched substrate of the fourth embodiment in which the second surface resin layer contains polyethylene and an adhesive resin is also referred to as the "stretched substrate of the fourth embodiment."

[0024] When describing matters common to the stretched substrates of the first to fourth embodiments, or when there is no particular distinction between the stretched substrates of the first to fourth embodiments, they are also simply referred to as "stretched substrate."

[0025] The stretched substrate has a first surface and a second surface opposite to the first surface. In one embodiment, the first surface resin layer constitutes the first surface, and the second surface resin layer constitutes the second surface.

[0026] The stretched substrate has a multi-layer structure of 3 or more layers. The number of layers of the stretched substrate is 3 or more, preferably 9 or less, more preferably 7 or less, for example, 3 to 9. The number of layers of the stretched substrate is specifically 3, 5, 7 or 9. The stretched substrate having a multi-layer structure has an excellent balance of, for example, gas barrier properties, strength, rigidity, heat resistance, transparency and printability.

[0027] The stretched substrate of the first embodiment may further comprise a first adhesive resin layer between the first surface resin layer and the polyethylene intermediate layer. The stretched substrate of the first embodiment may further comprise a second adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. The stretched substrate of the first embodiment may comprise a first surface resin layer, a first adhesive resin layer, a polyethylene intermediate layer, a second adhesive resin layer, and a second surface resin layer in this order. The stretched substrate of the first embodiment may comprise two or more polyethylene intermediate layers.

[0028] In the stretched substrate of the first embodiment, the compositions of the first and second surface resin layers may be the same or different from each other. The thicknesses of the first and second surface resin layers may be the same or different from each other. The compositions of the first and second adhesive resin layers may be the same or different from each other. The thicknesses of the first and second adhesive resin layers may be the same or different from each other.

[0029] The stretched substrate of the second embodiment may further include an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. The stretched substrate of the second embodiment may include a first surface resin layer, a polyethylene intermediate layer, an adhesive resin layer, and a second surface resin layer in this order. The stretched substrate of the second embodiment may include two or more polyethylene intermediate layers.

[0030] The stretched substrate of the second embodiment may include a first surface resin layer, a first polyethylene layer, a second polyethylene layer, an adhesive resin layer, and a second surface resin layer in this order. The compositions of the first and second polyethylene layers may be the same or different. The thicknesses of the first and second polyethylene layers may be the same or different.

[0031] The stretched base material of the third embodiment may include a first surface resin layer, a first polyethylene layer, a second polyethylene layer, a third polyethylene layer, and a second surface resin layer in this order. The compositions of the first and second surface resin layers may be the same as or different from each other. The thicknesses of the first and second surface resin layers may be the same as or different from each other. The compositions of the first to third polyethylene layers may be the same as or different from each other. The thicknesses of the first to third polyethylene layers may be the same as or different from each other.

[0032] The stretched substrate of the embodiment 4A may further include an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. The stretched substrate of the embodiment 4A may include a first surface resin layer, a polyethylene intermediate layer, an adhesive resin layer, and a second surface resin layer in this order. The stretched substrate of the embodiment 4A may include two or more polyethylene intermediate layers.

[0033] The stretched substrate of the fourth embodiment may include a first surface resin layer, a first polyethylene layer, a second polyethylene layer, an adhesive resin layer, and a second surface resin layer in this order. The compositions of the first and second polyethylene layers may be the same or different. The thicknesses of the first and second polyethylene layers may be the same or different.

[0034] The stretched substrate of the embodiment 4B may include a first surface resin layer, a first polyethylene layer, a second polyethylene layer, a third polyethylene layer, and a second surface resin layer in this order. The compositions of the first to third polyethylene layers may be the same as or different from each other. The thicknesses of the first to third polyethylene layers may be the same as or different from each other.

[0035] The content of polyethylene in the stretched substrate is preferably more than 50% by mass, more preferably 60% by mass or more, even more preferably 70% by mass or more, still more preferably 80% by mass or more, particularly preferably 85% by mass or more or 90% by mass or more. A laminate (or a packaging container) including such a stretched substrate has, for example, excellent recyclability.

[0036] The stretched substrate is a substrate that has been subjected to a stretching process. This can improve, for example, the strength, rigidity, heat resistance, transparency, and printability of the substrate. The stretching process may be a uniaxial stretching process or a biaxial stretching process. The biaxial stretching process may be a sequential biaxial stretching process by a tenter frame method or the like, or a simultaneous biaxial stretching process. The stretching ratio when stretching in the machine direction (flow direction of the substrate, MD direction) is preferably 2 times or more, more preferably 3 times or more, preferably 15 times or less, more preferably 10 times or less, for example, 2 times or more and 15 times or less. The stretching ratio when stretching in the width direction (direction perpendicular to the MD direction, TD direction) is preferably 2 times or more, more preferably 3 times or more, preferably 15 times or less, more preferably 10 times or less, for example, 2 times or more and 15 times or less.

[0037] The stretched substrate is, for example, a biaxially stretched substrate, specifically, a substrate that is biaxially stretched in the MD direction and the TD direction. The stretched substrate is, for example, a uniaxially stretched substrate, specifically, a substrate that is uniaxially stretched in the MD direction.

[0038] The thickness of the stretched substrate is preferably 5 μm or more, more preferably 10 μm or more, even more preferably 15 μm or more, and preferably 200 μm or less, more preferably 100 μm or less, even more preferably 50 μm or less, particularly preferably 30 μm or less, for example, 5 μm or more and 200 μm or less. A stretched substrate having a thickness equal to or greater than the lower limit has, for example, excellent strength, rigidity, and heat resistance. A stretched substrate having a thickness equal to or less than the upper limit has, for example, excellent processability. In this specification, the thickness of the substrate and each layer is the average value of the thicknesses at 10 points measured based on a scanning electron microscope (SEM) image obtained by observing a vertical cross section relative to the substrate surface with an SEM.

[0039] The stretched substrate can be produced, for example, by forming the materials constituting each layer into a laminated film, and then stretching the laminated film. Examples of the film-forming method include the T-die casting method and the inflation method, and the T-die casting method is preferred from the viewpoint of productivity.

[0040] In one embodiment, the stretched substrate is a stretched film of a coextruded resin film. In one embodiment, the stretched substrate is a resin film obtained by producing a laminated film by co-extrusion of a material constituting the first surface resin layer, a material constituting the polyethylene intermediate layer, and, if the stretched substrate has an adhesive resin layer, a material constituting the adhesive resin layer, and a material constituting the second surface resin layer, and then stretching the laminated film.

[0041] An embodiment of the co-extrusion T-die casting method will be described below. Materials for forming each layer are fed to each extruder, and co-extrusion T-die casting is performed to obtain a laminated film.

[0042] In the stretched substrate of the first embodiment, for example, in each extruder, the extrusion temperature for the surface resin layer containing an ethylene-vinyl alcohol copolymer, the extrusion temperature for the adhesive resin layer, and the extrusion temperature for the polyethylene intermediate layer are each set to 220° C. or more and 240° C. or less. In the stretched substrate of the first embodiment, for example, in each extruder, the extrusion temperature for the surface resin layer containing polyamide is set to 260° C. or more and 280° C. or less, the extrusion temperature for the adhesive resin layer is set to 220° C. or more and 270° C. or less, and the extrusion temperature for the polyethylene intermediate layer is set to 220° C. or more and 270° C. or less. In the stretched substrate of the second embodiment, for example, in each extruder, the extrusion temperature for the first surface resin layer, the extrusion temperature for the polyethylene intermediate layer, the extrusion temperature for the adhesive resin layer, and the extrusion temperature for the second surface resin layer containing an ethylene-vinyl alcohol copolymer are each set to 220° C. or more and 240° C. or less. In the stretched substrate of the second embodiment, for example, in each extruder, the extrusion temperature for the first surface resin layer is set to 220° C. or more and 240° C. or less, the extrusion temperature for the polyethylene intermediate layer is set to 220° C. or more and 260° C. or less, the extrusion temperature for the adhesive resin layer is set to 220° C. or more and 270° C. or less, and the extrusion temperature for the second surface resin layer containing polyamide is set to 260° C. or more and 280° C. or less. In the stretched base material of the third embodiment, for example, the extrusion temperature for the surface resin layer and the extrusion temperature for the polyethylene intermediate layer are set to 220° C. or higher and 240° C. or lower in each extruder. In the stretched substrate of the embodiment of 4A, for example, in each extruder, the extrusion temperature for the first surface resin layer, the extrusion temperature for the polyethylene intermediate layer, the extrusion temperature for the adhesive resin layer, and the extrusion temperature for the second surface resin layer containing an ethylene-vinyl alcohol copolymer are each set to 220°C or more and 240°C or less. In the stretched substrate of the embodiment of 4A, for example, in each extruder, the extrusion temperature for the first surface resin layer is set to 220°C or more and 260°C or less, the extrusion temperature for the polyethylene intermediate layer is set to 220°C or more and 260°C or less, the extrusion temperature for the adhesive resin layer is set to 220°C or more and 270°C or less, and the extrusion temperature for the second surface resin layer containing polyamide is set to 260°C or more and 280°C or less. In the stretched substrate of the embodiment of 4B, for example, in each extruder, the extrusion temperature for the first surface resin layer, the extrusion temperature for the polyethylene intermediate layer, and the extrusion temperature for the second surface resin layer containing polyethylene and an adhesive resin are each set to 220°C or more and 240°C or less. These extrusion temperatures in the extruder are merely examples and can be changed as appropriate.

[0043] The stretched substrate and the barrier substrate described later may be subjected to a surface treatment. Such a stretched substrate and a barrier substrate have, for example, excellent adhesion to other layers. Examples of the surface treatment method include physical treatment and chemical treatment. Examples of the physical treatment include corona treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment. Examples of the chemical treatment include oxidation treatment using chemicals.

[0044] The stretched substrate may further include a printing layer, which will be described later.

[0045] <Polyethylene intermediate layer> The polyethylene intermediate layer contains polyethylene as a main component. As the polyethylene, for example, high density polyethylene, medium density polyethylene, low density polyethylene and linear low density polyethylene are preferable. From the viewpoint of strength and heat resistance of the stretched substrate, high density polyethylene and medium density polyethylene are preferable. From the viewpoint of film formability and processability of the stretched substrate, linear low density polyethylene and medium density polyethylene are preferable.

[0046] The linear low density polyethylene may, for example, be ethylene-1-butene copolymer (C4-LLDPE) whose comonomer is at least 1-butene, ethylene-1-hexene copolymer (C6-LLDPE) whose comonomer is at least 1-hexene, and ethylene-1-octene copolymer (C8-LLDPE) whose comonomer is at least 1-octene.In these copolymers, the comonomers are not limited to the above-mentioned ones, and further comonomers may be used.For example, linear low density polyethylene produced using metallocene catalyst is preferred.

[0047] The melting point (Tm) of the polyethylene in the polyethylene intermediate layer is preferably 100° C. or higher, more preferably 105° C. or higher, even more preferably 110° C. or higher, particularly preferably 115° C. or higher, and preferably 140° C. or lower, for example, 100° C. or higher and 140° C. or lower, from the viewpoints of the strength and heat resistance of the stretched substrate. In this specification, the Tm of various materials is the melting peak temperature obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121:2012 (using test pieces after conditioning according to 3.(2) (wherein a cooling rate of 10° C. / min)).

[0048] The polyethylene content in the polyethylene intermediate layer is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0049] The polyethylene intermediate layer may contain a resin material other than polyethylene, such as polyolefins other than polyethylene, polyesters, polyamides, (meth)acrylic resins, vinyl resins, cellulose resins, and ionomer resins.

[0050] The polyethylene intermediate layer may contain additives, such as crosslinkers, antioxidants, UV absorbers, light stabilizers, antiblocking agents, slip agents, fillers, reinforcing agents, antistatic agents, compatibilizers, pigments, and modifying resins.

[0051] In one embodiment, the polyethylene intermediate layer is a layer containing at least one polyethylene selected from high density polyethylene and medium density polyethylene (hereinafter also referred to as "polyethylene layer (1)"), or a layer containing polyethylene as a main component, and the polyethylene contained in the layer has a density of 0.930 g / cm 3 Super 0.960g / cm 3 The layer (hereinafter also referred to as “polyethylene layer (2)”) has the following density.

[0052] (Polyethylene layer (1)) The polyethylene layer (1) contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, and preferably contains high density polyethylene. Therefore, the stretched substrate having the polyethylene layer (1) has high heat resistance, for example, and specifically, excellent resistance to drying during printing and heating during heat sealing, and excellent resistance to deposition when deposition is performed on the film. In addition, the polyethylene layer (1) has high rigidity, for example, and can increase the film conveying speed when deposition is performed on the film, thereby increasing productivity.

[0053] Examples of high-density polyethylene include ethylene homopolymers and ethylene-α-olefin copolymers. Examples of α-olefins include the above-mentioned α-olefins having 3 to 20 carbon atoms, with α-olefins having 3 to 8 carbon atoms being preferred, and α-olefins having 4 to 8 carbon atoms being more preferred. Examples of ethylene-α-olefin copolymers include ethylene-1-butene copolymers (C4-HDPE) in which the comonomer is at least 1-butene, ethylene-1-hexene copolymers (C6-HDPE) in which the comonomer is at least 1-hexene, and ethylene-1-octene copolymers (C8-HDPE) in which the comonomer is at least 1-octene. In these copolymers, the comonomers are not limited to the above-mentioned comonomers, and further comonomers may be used. For example, high-density polyethylenes produced using metallocene catalysts are preferred.

[0054] Examples of the medium density polyethylene include ethylene homopolymers and ethylene-α-olefin copolymers. Examples of the α-olefins include the above-mentioned α-olefins having 3 to 20 carbon atoms, with α-olefins having 3 to 8 carbon atoms being preferred, and α-olefins having 4 to 8 carbon atoms being more preferred. Examples of the ethylene-α-olefin copolymers include ethylene-1-butene copolymers (C4-MDPE) in which the comonomer is at least 1-butene, ethylene-1-hexene copolymers (C6-MDPE) in which the comonomer is at least 1-hexene, and ethylene-1-octene copolymers (C8-MDPE) in which the comonomer is at least 1-octene. In these copolymers, the comonomers are not limited to the above-mentioned comonomers, and further comonomers may be used. For example, medium density polyethylenes produced using metallocene catalysts are preferred.

[0055] The high density polyethylene and the medium density polyethylene are preferably the above-mentioned ethylene-α-olefin copolymers. Films containing such high density polyethylene and / or medium density polyethylene are, for example, excellent in biaxial stretchability, particularly excellent in stretchability in the width direction. This is presumably because the side chains derived from the α-olefins prevent the film from tearing during stretching. The ethylene-α-olefin copolymers are preferably polyethylenes obtained by polymerizing ethylene and a small amount of α-olefins by a polymerization method using a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst, and more preferably polyethylenes produced using a metallocene catalyst.

[0056] The density of the high density polyethylene is preferably 0.945 g / cm 3 Exceeds 0.960g / cm 3 The density of the medium density polyethylene is preferably 0.930 g / cm 3 Exceeds 0.945g / cm 3The density can be adjusted, for example, by the amount of structural units derived from the α-olefin, which is a comonomer in the ethylene-α-olefin copolymer, introduced.

[0057] The polyethylene layer (1) may, for example, contain high density polyethylene as a main component, may contain medium density polyethylene as a main component, or may contain a mixture of high density polyethylene and medium density polyethylene as a main component. The polyethylene layer (1) may, for example, contain as a main component a mixture of high-density polyethylene and other polyethylene, may contain as a main component a mixture of medium-density polyethylene and other polyethylene, or may contain as a main component a mixture of high-density polyethylene, medium-density polyethylene, and other polyethylene. The main component being the above mixture means that the content of the above mixture in the polyethylene layer (1) is more than 50% by mass, and the above content is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. The high-density polyethylene may be, for example, an ethylene homopolymer, an ethylene-α-olefin copolymer, or a mixture thereof. The medium-density polyethylene may be, for example, an ethylene homopolymer, an ethylene-α-olefin copolymer, or a mixture thereof. The other polyethylene may be, for example, at least one selected from linear low-density polyethylene and high-pressure low-density polyethylene, and may be linear low-density polyethylene, high-pressure low-density polyethylene, or a mixture of linear low-density polyethylene and high-pressure low-density polyethylene.

[0058] From the viewpoint of heat resistance, the total content of high-density polyethylene and medium-density polyethylene in the polyethylene layer (1) is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, and may be 30% by mass or more, 35% by mass or more, or 40% by mass or more. The total content of high density polyethylene and medium density polyethylene in the polyethylene layer (1) is 100% by mass or less, and from the viewpoint of biaxial stretchability, is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, may be 70% by mass or less, 65% by mass or less, or may be 60% by mass or less. The total content of high density polyethylene and medium density polyethylene in the polyethylene layer (1) is, for example, from 10% by mass to 100% by mass, and preferably from 20% by mass to 60% by mass.

[0059] When the polyethylene layer (1) is the surface resin layer of the film, a small total content ratio tends to improve the adhesion between the surface resin layer and a printed layer or a vapor deposition film, etc., by the above-mentioned surface treatment. This is presumably because, for example, high-density polyethylene has high crystallinity, and polar groups may not be sufficiently introduced into the polyethylene layer by surface treatment such as corona treatment, whereas a small total content ratio allows polar groups to be sufficiently introduced into the polyethylene layer by surface treatment such as corona treatment. Furthermore, when the polyethylene layer (1) is the surface resin layer of the film, a small total content ratio tends to provide the film with excellent appearance, surface smoothness, and transparency.

[0060] From the viewpoint of biaxial stretchability, the polyethylene layer (1) preferably contains a linear low-density polyethylene in addition to at least one polyethylene selected from high-density polyethylene and medium-density polyethylene, and more preferably contains a linear low-density polyethylene in addition to the high-density polyethylene.

[0061] Examples of linear low density polyethylene include ethylene-α-olefin copolymers. Examples of α-olefins include the above-mentioned α-olefins having 3 to 20 carbon atoms, with α-olefins having 3 to 8 carbon atoms being preferred, and α-olefins having 4 to 8 carbon atoms being more preferred. Examples of linear low density polyethylene include ethylene-1-butene copolymers (C4-LLDPE) in which the comonomer is at least 1-butene, ethylene-1-hexene copolymers (C6-LLDPE) in which the comonomer is at least 1-hexene, and ethylene-1-octene copolymers (C8-LLDPE) in which the comonomer is at least 1-octene. In these copolymers, the comonomers are not limited to the above-mentioned comonomers, and further comonomers may be used. For example, linear low density polyethylenes produced using a metallocene catalyst are preferred. The density of the linear low density polyethylene is preferably 0.900 g / cm 3 More than 0.930g / cm 3 The following is the result.

[0062] The content of the linear low-density polyethylene in the polyethylene layer (1) is, from the viewpoint of biaxial stretchability, preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, and may be 30% by mass or more, 35% by mass or more, or 40% by mass or more. From the viewpoint of heat resistance, the content of the linear low-density polyethylene in the polyethylene layer (1) is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less, and may be 70% by mass or less, 65% by mass or less, or 60% by mass or less. The content of the linear low-density polyethylene in the polyethylene layer (1) is, for example, from 10% by mass to 90% by mass, and preferably from 40% by mass to 80% by mass.

[0063] The polyethylene layer (1) contains polyethylene as a main component. The content of polyethylene in the polyethylene layer (1) is preferably 80% by mass or more, more preferably 85% by mass or more, further preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0064] The polyethylene layer (1) may contain polyethylene other than high density polyethylene, medium density polyethylene and linear low density polyethylene, or the above-mentioned resin materials other than polyethylene. The polyethylene layer (1) may contain the above-mentioned additives.

[0065] (Polyethylene layer (2)) The polyethylene layer (2) contains polyethylene as a main component, and the polyethylene has a viscosity of 0.930 g / cm 3 Super 0.960g / cm 3 The density of the polyethylene in the polyethylene layer (2) is preferably 0.931 g / cm 3 More than 0.955g / cm 3 Less than or equal to 0.931 g / cm 3 More than 0.950g / cm 3 The following is the result.

[0066] When the polyethylene layer (2) contains two or more kinds of polyethylene with different densities, the density of the polyethylene means the density of a mixture of two or more kinds of polyethylene. The density is measured for polyethylene sampled from the layer in accordance with JIS K7112:1999 D method (density gradient tube method, 23°C). When the measurement is difficult, the average density D calculated according to the following formula is used: av may be the density of the polyethylene constituting the layer.

[0067] D av = ΣW i ×D i In the formula, Σ is W from 1 to n (n types of polyethylene are present) for i. i ×D i where n is an integer equal to or greater than 2, and W iindicates the mass fraction of the i-th polyethylene, and D i is the density of the i-th polyethylene (g / cm 3 ) is shown.

[0068] The density of the polyethylene layer (2) can be adjusted based on the composition described above for the polyethylene layer (1), for example. That is, the polyethylene layer (2) can have the composition described above for the polyethylene layer (1). The polyethylene layer (2) may contain the above-mentioned resin materials other than polyethylene. The polyethylene layer (2) may contain the above-mentioned additives.

[0069] In the stretched substrate of the first embodiment, the thickness of the polyethylene intermediate layer is preferably 4 μm or more, more preferably 6 μm or more, even more preferably 8 μm or more, and preferably 60 μm or less, more preferably 40 μm or less, even more preferably 20 μm or less, for example, 4 μm or more and 60 μm or less. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or greater than the lower limit is, for example, excellent in strength, rigidity, heat resistance, and recyclability. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or less than the upper limit is, for example, excellent in processability. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" means the sum of the thicknesses of the polyethylene intermediate layers.

[0070] In the stretched substrate of the first embodiment, the thickness of the polyethylene intermediate layer is preferably 40% or more, more preferably 50% or more, even more preferably 60% or more, and preferably 90% or less, more preferably 85% or less, even more preferably 80% or less, for example, 40% or more and 90% or less, relative to the thickness of the stretched substrate. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" means the total thickness of each polyethylene intermediate layer.

[0071] In the stretched substrate of the second embodiment and the fourth embodiment, the thickness of the polyethylene intermediate layer is preferably 5 μm or more, more preferably 8 μm or more, even more preferably 10 μm or more, and preferably 100 μm or less, more preferably 80 μm or less, even more preferably 60 μm or less, even more preferably 40 μm or less, and particularly preferably 30 μm or less, for example, 5 μm or more and 100 μm or less. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or greater than the lower limit is, for example, excellent in strength, rigidity, heat resistance, and recyclability. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or less than the upper limit is, for example, excellent in processability. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" means the sum of the thicknesses of the polyethylene intermediate layers.

[0072] In the stretched substrates of the second and fourth Aspects, the thickness of the polyethylene intermediate layer is preferably 45% or more, more preferably 55% or more, even more preferably 65% ​​or more, and preferably 95% or less, more preferably 90% or less, even more preferably 85% or less, for example 45% or more and 95% or less, relative to the thickness of the stretched substrate. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" refers to the total thickness of each of the polyethylene intermediate layers.

[0073] In the stretched substrate of the third embodiment and the fourth embodiment, the thickness of the polyethylene intermediate layer is preferably 6 μm or more, more preferably 10 μm or more, even more preferably 14 μm or more, and preferably 100 μm or less, more preferably 80 μm or less, even more preferably 60 μm or less, even more preferably 40 μm or less, and particularly preferably 30 μm or less, for example, 6 μm or more and 100 μm or less. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or greater than the lower limit is excellent in, for example, strength, rigidity, heat resistance, and recyclability. A stretched substrate having a polyethylene intermediate layer whose thickness is equal to or less than the upper limit is excellent in, for example, processability. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" means the sum of the thicknesses of the polyethylene intermediate layers.

[0074] In the stretched substrate of the third embodiment, the thickness of the polyethylene intermediate layer is preferably 60% or more, more preferably 70% or more, even more preferably 80% or more, particularly preferably 84% or more, and is preferably 98% or less, more preferably 96% or less, even more preferably 92% or less, for example, 60% or more and 98% or less, relative to the thickness of the stretched substrate. When the stretched substrate has two or more polyethylene intermediate layers, the above "thickness" means the total thickness of each polyethylene intermediate layer.

[0075] The stretched substrate may have one or more intermediate polyethylene layers.

[0076] The stretched substrate of the second embodiment and the fourth embodiment may comprise, in this order, a first surface resin layer, a first polyethylene layer, a second polyethylene layer, an adhesive resin layer, and a second surface resin layer. The stretched substrate having the above layer structure will now be described.

[0077] From the viewpoint of better exerting the above-mentioned effects, the thickness of the second polyethylene layer is preferably 4 μm or more, more preferably 6 μm or more, even more preferably 8 μm or more, and is preferably 60 μm or less, more preferably 40 μm or less, even more preferably 20 μm or less, for example, 4 μm or more and 60 μm or less.

[0078] The thickness of the second polyethylene layer is preferably 40% or more, more preferably 50% or more, even more preferably 60% or more, and preferably 90% or less, more preferably 85% or less, even more preferably 80% or less, for example, 40% or more and 90% or less, of the thickness of the stretched substrate.

[0079] The thickness of the first polyethylene layer is preferably 0.5 μm or more, more preferably 0.8 μm or more, even more preferably 1 μm or more, and preferably 18 μm or less, more preferably 13 μm or less, even more preferably 8 μm or less, particularly preferably 5 μm or less, for example, 0.5 μm or more and 18 μm or less.

[0080] The thickness of the first polyethylene layer is preferably 2% or more, more preferably 4% or more, even more preferably 6% or more, and is preferably 25% or less, more preferably 20% or less, even more preferably 15% or less, particularly preferably 10% or less, for example, 2% or more and 25% or less, relative to the thickness of the stretched substrate.

[0081] In a stretched substrate having a first surface resin layer, a first polyethylene layer, a second polyethylene layer, an adhesive resin layer, and a second surface resin layer, in this order, the ratio of the thickness of the first polyethylene layer to the thickness of the adhesive resin layer is preferably 0.6 or more and 1.4 or less, more preferably 0.7 or more and 1.3 or less, even more preferably 0.8 or more and 1.2 or less, and particularly preferably 0.9 or more and 1.1 or less, from the viewpoints of symmetry of the stretched substrate and suppression of curling.

[0082] The polyethylene intermediate layer may further contain a compatibilizer. By containing the compatibilizer in the polyethylene intermediate layer, the mixability between the gas barrier resin and the polyethylene can be improved when the stretched substrate and the barrier substrate are heated and melted for recycling. This can effectively prevent the physical properties of the polyethylene from decreasing after recycling, and can also effectively prevent the transparency of the polyethylene from decreasing. When the stretched substrate has two or more polyethylene intermediate layers, at least one of the polyethylene intermediate layers may contain a compatibilizer.

[0083] When the polyethylene intermediate layer contains a compatibilizer, the content of the compatibilizer in the polyethylene intermediate layer is preferably 25 parts by mass or more and 200 parts by mass or less relative to 100 parts by mass of the gas barrier resin in the stretched substrate. For example, when the gas barrier resin is an ethylene-vinyl alcohol copolymer, the content of the compatibilizer in the polyethylene intermediate layer is preferably 100 parts by mass or more and 200 parts by mass or less relative to 100 parts by mass of the ethylene-vinyl alcohol copolymer in the stretched substrate. For example, when the gas barrier resin is a polyamide, the content of the compatibilizer in the polyethylene intermediate layer is preferably 25 parts by mass or more and 100 parts by mass or less relative to 100 parts by mass of the polyamide in the stretched substrate.

[0084] Examples of the compatibilizer include acid-modified polyolefins, and from the viewpoint of recyclability, acid-modified polyethylene and acid-modified polypropylene are preferred. Examples of the acid-modified polyolefin include polyolefins modified with unsaturated carboxylic acids such as maleic acid and fumaric acid, or their acid anhydrides, esters, or metal salts, particularly graft-modified polyolefins. Specifically, the compatibilizer is preferably unsaturated carboxylic acid compound-modified polyethylene and unsaturated carboxylic acid compound-modified polypropylene, and more preferably maleic anhydride-modified polyethylene and maleic anhydride-modified polypropylene.

[0085] In one embodiment of the stretched substrate of the first aspect, the polyethylene intermediate layer may further contain a compatibilizer. The content of polyethylene in the polyethylene intermediate layer is preferably more than 50% by mass, more preferably 60% by mass or more, even more preferably 65% ​​by mass or more, even more preferably 70% by mass or more, particularly preferably 75% by mass or more or 80% by mass or more. The content of polyethylene in the polyethylene intermediate layer is 100% by mass or less, may be 99% by mass or less, may be 97% by mass or less, may be 95% by mass or less, or may be 90% by mass or less. When the polyethylene intermediate layer contains a compatibilizer, the content of the compatibilizer in the polyethylene intermediate layer is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, even more preferably 10% by mass or more, preferably 40% by mass or less, more preferably 35% by mass or less, even more preferably 30% by mass or less, particularly preferably 25% by mass or less or 20% by mass or less.

[0086] In one embodiment of the stretched substrate of the second aspect and the fourth aspect, the second polyethylene layer may further contain a compatibilizer. The content of polyethylene in the second polyethylene layer is preferably more than 50% by mass, more preferably 60% by mass or more, even more preferably 65% ​​by mass or more, even more preferably 70% by mass or more, particularly preferably 75% by mass or more or 80% by mass or more. The content of polyethylene in the second polyethylene layer is 100% by mass or less, may be 99% by mass or less, or may be 97% by mass or less. When the second polyethylene layer contains a compatibilizer, the content of the compatibilizer in the second polyethylene layer is preferably 1% by mass or more, more preferably 3% by mass or more, preferably 40% by mass or less, more preferably 35% by mass or less, even more preferably 30% by mass or less, particularly preferably 25% by mass or less or 20% by mass or less.

[0087] The stretched substrate of the third embodiment and the fourth embodiment may comprise, in this order, a first surface resin layer, a first polyethylene layer, a second polyethylene layer, a third polyethylene layer, and a second surface resin layer. The stretched substrate having the above layer structure will now be described.

[0088] From the viewpoint of better exerting the above-mentioned effects, the thickness of the second polyethylene layer is preferably 4 μm or more, more preferably 6 μm or more, even more preferably 8 μm or more, and is preferably 60 μm or less, more preferably 40 μm or less, even more preferably 20 μm or less, for example, 4 μm or more and 60 μm or less.

[0089] The thickness of the second polyethylene layer is preferably 40% or more, more preferably 50% or more, even more preferably 60% or more, and preferably 90% or less, more preferably 85% or less, even more preferably 80% or less, for example, 40% or more and 90% or less, of the thickness of the stretched substrate.

[0090] The thickness of the first and third polyethylene layers is each independently preferably 0.5 μm or more, more preferably 0.8 μm or more, even more preferably 1 μm or more, and preferably 18 μm or less, more preferably 13 μm or less, even more preferably 8 μm or less, particularly preferably 5 μm or less, for example, 0.5 μm or more and 18 μm or less.

[0091] The thicknesses of the first and third polyethylene layers are each independently preferably 2% or more, more preferably 4% or more, even more preferably 6% or more, and preferably 25% or less, more preferably 20% or less, even more preferably 15% or less, particularly preferably 10% or less, for example, 2% or more and 25% or less, relative to the thickness of the stretched substrate.

[0092] In a stretched substrate having a first surface resin layer, a first polyethylene layer, a second polyethylene layer, a third polyethylene layer, and a second surface resin layer, in this order, the ratio of the thickness of the first polyethylene layer to the thickness of the third polyethylene layer is preferably 0.6 or more and 1.4 or less, more preferably 0.7 or more and 1.3 or less, even more preferably 0.8 or more and 1.2 or less, and particularly preferably 0.9 or more and 1.1 or less, from the viewpoints of symmetry of the stretched substrate and suppression of curling.

[0093] <First and second surface resin layers in the first embodiment, Second Surface Resin Layer in the Second and Fourth Aspects> In the stretched substrate of the first embodiment, the first and second surface resin layers each independently contain a gas barrier resin as a main component. In the stretched substrate of the second embodiment, the second surface resin layer contains a gas barrier resin as a main component. In the stretched substrate of the 4A embodiment, the second surface resin layer contains a gas barrier resin as a main component. Such a surface resin layer tends to have excellent surface smoothness, and the vapor deposition film provided on the surface of the surface resin layer tends to have excellent adhesion to the surface resin layer and to exhibit good gas barrier properties.

[0094] The stretched substrate of the above embodiment has the above surface resin layer, and therefore has superior gas barrier properties (particularly oxygen barrier properties), heat resistance and rigidity, for example, compared to conventional stretched polyethylene films.

[0095] The gas barrier resin is a resin having a function of suppressing gas permeation. Examples of the gas barrier resin include ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyamide, polyvinylidene chloride, polyester, polyether polyol, polyester polyol, polyurethane, polyacrylonitrile, and (meth)acrylic resin. Among these, from the viewpoints of gas barrier properties (particularly oxygen barrier properties), heat resistance, and rigidity, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, and polyamide are preferred, and ethylene-vinyl alcohol copolymer and polyamide are more preferred. It is also preferred that the surface resin layer contains at least polyamide as a gas barrier resin.

[0096] Ethylene-vinyl alcohol copolymer (EVOH) can be obtained, for example, by copolymerizing ethylene with a vinyl ester monomer and then saponifying the copolymer. The copolymerization of ethylene with a vinyl ester monomer can be carried out by any known polymerization method, for example, solution polymerization, suspension polymerization, emulsion polymerization, etc. EVOH may be modified by known methods such as urethanization, acetalization, cyanoethylation, oxyalkylenation, etc.

[0097] As the vinyl ester monomer, vinyl acetate is generally used, but other vinyl ester monomers may be used, such as aliphatic vinyl esters such as vinyl formate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl caprate, vinyl laurate, vinyl stearate, and vinyl versatate, and aromatic vinyl esters such as vinyl benzoate.

[0098] The content ratio of structural units derived from ethylene in EVOH (ethylene content ratio) is preferably 20 mol% or more, more preferably 25 mol% or more, based on the total repeating structural units, from the viewpoint of processability of the stretched substrate, and is even more preferably 30 mol% or more, even more preferably 35 mol% or more, and particularly preferably 40 mol% or more or 45 mol% or more, based on the viewpoint of excellent surface smoothness and stretchability, particularly biaxial stretchability. The ethylene content ratio in EVOH is preferably 60 mol% or less, more preferably 55 mol% or less, based on the total repeating structural units, from the viewpoint of heat resistance, oxygen barrier property, and water vapor barrier property of the stretched substrate. The ethylene content ratio is, for example, 20 mol% or more and 60 mol% or less. The ethylene content ratio is measured by NMR.

[0099] The average saponification degree of EVOH is preferably 90 mol% or more, more preferably 95 mol% or more, and further preferably 99 mol% or more. The average saponification degree is measured in accordance with JIS K6726:1994 (wherein EVOH is used as a solution uniformly dissolved in a water / methanol solvent).

[0100] The melting point (Tm) of EVOH is preferably 130°C or higher, more preferably 135°C or higher, even more preferably 140°C or higher, and is preferably 200°C or lower, more preferably 190°C or lower, even more preferably 180°C or lower, still more preferably 170°C or lower, particularly preferably 165°C or lower, for example, 130°C or higher and 200°C or lower.

[0101] From the viewpoint of film-forming property and processability, the MFR of EVOH is preferably 0.1 g / 10 min or more, more preferably 1 g / 10 min or more, even more preferably 1.5 g / 10 min or more, and preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, even more preferably 10 g / 10 min or less, for example, 0.1 g / 10 min or more and 50 g / 10 min or less. The MFR of EVOH is measured by the A method under the conditions of a temperature of 190 ° C and a load of 2.16 kg in accordance with JIS K7210-1:2014. The measurement temperature may be 210 ° C depending on the melting point of EVOH.

[0102] The average saponification degree of polyvinyl alcohol (PVA) is preferably 70 mol% or more, more preferably 75 mol% or more, further preferably 80 mol% or more, and particularly preferably 85 mol% or more. The average saponification degree is measured in accordance with JIS K6726:1994.

[0103] Examples of polyamides include aliphatic polyamides and aromatic polyamides. The surface resin layer preferably contains at least aromatic polyamide as a gas barrier resin. Such a stretched substrate has, for example, excellent rigidity and gas barrier properties. In the following examples, polyamide is also referred to as "PA."

[0104] The aromatic polyamide includes semi-aromatic polyamide and fully aromatic polyamide, and semi-aromatic polyamide is preferable. Semi-aromatic polyamide is a polyamide having a structural unit derived from aromatic diamine and a structural unit derived from aliphatic dicarboxylic acid, or a polyamide having a structural unit derived from aliphatic diamine and a structural unit derived from aromatic dicarboxylic acid. For example, polyamide composed of aromatic diamine and aliphatic dicarboxylic acid, and polyamide composed of aliphatic diamine and aromatic dicarboxylic acid can be mentioned.

[0105] Examples of semi-aromatic polyamides include polyhexamethylene terephthalamide (PA6T), polyhexamethylene isophthalamide (PA6I), polynonamethylene terephthalamide (PA9T), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (PA66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (PA66 / 6I), polyhexamethylene terephthalamide / polycaproamide copolymer (PA6T / 6), polyhexamethylene isophthalamide / polycaproamide copolymer (PA6I / 6), polyhexamethylene terephthalamide / poly Examples of the poly(2-methylpentamethylene terephthalamide) copolymer include dodecamide copolymer (PA6T / 12), polyhexamethylene isophthalamide / polyhexamethylene terephthalamide copolymer (PA6I / 6T), polyhexamethylene terephthalamide / poly(2-methylpentamethylene terephthalamide) copolymer (PA6T / M5T), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (PA66 / 6T / 6I), polyhexamethylene adipamide / polycaproamide / polyhexamethylene isophthalamide copolymer (PA66 / 6 / 6I) and polymetaxylylene adipamide (PAMXD6). Among these, polymetaxylylene adipamide (PAMXD6) is preferred.

[0106] The semi-aromatic polyamide is preferably a crystalline semi-aromatic polyamide. The melting point (Tm) of the crystalline semi-aromatic polyamide is preferably 190°C or higher, more preferably 200°C or higher, and even more preferably 210°C or higher, and is preferably 310°C or lower, more preferably 280°C or lower, and even more preferably 250°C or lower, for example, 190°C or higher and 310°C or lower.

[0107] Examples of the aliphatic polyamide include aliphatic homopolyamides and aliphatic copolymer polyamides.

[0108] Specific examples of aliphatic homopolyamides include polycaprolactam or poly(6-aminocaproic acid) (PA6), polyenantholactam or poly(7-aminoenanthic acid) (PA7), polyundecane lactam or poly(11-aminoundecanoic acid) (PA11), polylauryllactam or poly(12-aminolauric acid) (PA12), polyhexamethylene adipamide (PA66), polytetramethylene dodecamide (PA412), polypentamethylene azelamide (PA59), polypentamethylene sebacamide (PA510), polypentamethylene dodecamide (PA512), polyhexamethylene azelamide (PA69), polyhexamethylene sebacamide (PA510), polypentamethylene dodecamide (PA512), polyhexamethylene azelamide (PA510), polyhexamethylene sebac ... Polyhexamethylene dodecamide (PA610), polyhexamethylene dodecamide (PA612), polynonamethylene adipamide (PA96), polynonamethylene azelamide (PA99), polynonamethylene sebacamide (PA910), polynonamethylene dodecamide (PA912), polydecamethylene adipamide (PA106), polydecamethylene azelamide (PA109), polydecamethylene decamamide (PA1010), polydecamethylene dodecamide (PA1012), polydodecamethylene adipamide (PA126), polydodecamethylene azelamide (PA129), polydodecamethylene sebacamide (PA1210) and polydodecamethylene dodecamide (PA1212).

[0109] Specific examples of aliphatic copolymer polyamides include caprolactam / hexamethylenediaminoadipic acid copolymer (PA6 / 66), caprolactam / hexamethylenediaminoazelaic acid copolymer (PA6 / 69), caprolactam / hexamethylenediaminosebacic acid copolymer (PA6 / 610), caprolactam / hexamethylenediaminoundecanoic acid copolymer (PA6 / 611), caprolactam / hexamethylenediaminododecanoic acid copolymer (PA6 / 612), caprolactam / amino undecanoic acid copolymer (PA6 / 11), caprolactam / lauryllactam copolymer (PA6 / 12), caprolactam / hexamethylenediaminoadipic acid / lauryllactam copolymer (PA6 / 66 / 12), caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminosebacic acid copolymer (PA6 / 66 / 610), caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminododecanedicarboxylic acid copolymer (PA6 / 66 / 612).

[0110] The aliphatic polyamide is preferably a crystalline aliphatic polyamide. Examples of the crystalline aliphatic polyamide include PA6, PA11, PA12, PA66, PA610, PA612, PA6 / 66 and PA6 / 66 / 12. The melting point (Tm) of the crystalline aliphatic polyamide is preferably 180°C or higher, more preferably 190°C or higher, even more preferably 200°C or higher, and is preferably 300°C or lower, more preferably 270°C or lower, even more preferably 240°C or lower, for example, 180°C or higher and 300°C or lower.

[0111] The relative viscosity of the polyamide is preferably 1.5 or more, more preferably 2.0 or more, even more preferably 2.5 or more, and preferably 5.0 or less, more preferably 4.5 or less, even more preferably 4.0 or less, for example, 1.5 or more and 5.0 or less. The relative viscosity of the polyamide is measured at 25° C. by dissolving 1 g of the polyamide in 100 mL of 96% concentrated sulfuric acid in accordance with JIS K6920-2:2009.

[0112] The MFR of the polyamide is preferably 0.1 g / 10 min or more, more preferably 0.3 g / 10 min or more, even more preferably 0.5 g / 10 min or more, and preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, even more preferably 10 g / 10 min or less, for example, 0.1 g / 10 min or more and 50 g / 10 min or less. The MFR of the polyamide is measured by the A method under a load of 2.16 kg in accordance with JIS K7210-1:2014. An appropriate measurement temperature can be adopted depending on the melting point of the polyamide.

[0113] In the stretched substrate of the first embodiment, the content of the gas barrier resin in the first and second surface resin layers is, independently, from the viewpoint of the above-mentioned physical properties such as gas barrier property, preferably 80 mass % or more, more preferably 85 mass % or more, even more preferably 90 mass % or more, and particularly preferably 95 mass % or more.

[0114] In the stretched substrates of the second embodiment and the fourth embodiment, the content of the gas barrier resin in the second surface resin layer is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more, from the viewpoint of the above-mentioned physical properties such as gas barrier property.

[0115] The surface resin layer may contain an aliphatic polyamide as a main component. For example, the content of the aliphatic polyamide in the surface resin layer is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more, from the viewpoint of the above-mentioned physical properties such as the processability of the stretched substrate.

[0116] The surface resin layer may contain aromatic polyamide as a main component. For example, the content of aromatic polyamide in the surface resin layer is preferably 80% by mass or more, more preferably 85% by mass or more, further preferably 90% by mass or more, particularly preferably 95% by mass or more, from the viewpoint of the above-mentioned physical properties such as the rigidity and gas barrier property of the stretched substrate.

[0117] The surface resin layer may contain aromatic polyamide and aliphatic polyamide. Aromatic polyamide tends to be more excellent in gas barrier properties and rigidity. Aliphatic polyamide tends to be more excellent in processability. For example, in the surface resin layer, from the viewpoint of the balance of rigidity, gas barrier properties, processability and manufacturing cost of the stretched substrate, the content ratio of aromatic polyamide is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, even more preferably 30% by mass or more and 70% by mass or less, particularly preferably 40% by mass or more and 60% by mass or less, and the content ratio of aliphatic polyamide is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, even more preferably 30% by mass or more and 70% by mass or less, particularly preferably 40% by mass or more and 60% by mass or less.

[0118] The surface resin layer may contain the above-mentioned resin materials other than the above-mentioned components. The surface resin layer may contain the additive.

[0119] In the stretched substrate of the first embodiment, the thicknesses of the first and second surface resin layers are each independently preferably 0.3 μm or more, more preferably 0.5 μm or more, and even more preferably 0.8 μm or more, from the viewpoint of the above-mentioned physical properties such as gas barrier properties. In the stretched substrate of the first embodiment, the thicknesses of the first and second surface resin layers are each independently preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, and particularly preferably 3 μm or less, from the viewpoint of the recyclability of the stretched substrate and the barrier substrate. The thicknesses of the first and second surface resin layers are, for example, 0.3 μm or more and 15 μm or less. When the surface resin layer has a convex portion due to the particles described later, it is preferable that the thickness of each layer is measured in an area where the convex portion due to the particles is not formed. The same applies to other embodiments.

[0120] In the stretched substrate of the first embodiment, the thickness of the first and second surface resin layers is, independently of each other, preferably 1% or more, more preferably 2% or more, even more preferably 4% or more, and preferably 20% or less, more preferably 15% or less, even more preferably 10% or less, particularly preferably 8% or less, for example, 1% or more and 20% or less, relative to the thickness of the stretched substrate.

[0121] In the stretched substrate of the second embodiment and the fourth embodiment, the thickness of the second surface resin layer is preferably 0.3 μm or more, more preferably 0.5 μm or more, and even more preferably 0.8 μm or more, from the viewpoint of the above-mentioned physical properties such as gas barrier properties. In the stretched substrate of the second embodiment and the fourth embodiment, the thickness of the second surface resin layer is preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, and particularly preferably 3 μm or less, from the viewpoint of the recyclability of the stretched substrate and the barrier substrate. The thickness of the second surface resin layer is, for example, 0.3 μm or more and 15 μm or less.

[0122] In the stretched substrates of the second embodiment and the fourth embodiment, the thickness of the second surface resin layer is preferably 1% or more, more preferably 2% or more, even more preferably 4% or more, and is preferably 20% or less, more preferably 15% or less, even more preferably 10% or less, particularly preferably 8% or less, for example, 1% or more and 20% or less, relative to the thickness of the stretched substrate.

[0123] In each embodiment of the stretched substrate, the ratio of the thickness of the second surface resin layer to the thickness of the first surface resin layer is, from the viewpoints of symmetry of the stretched substrate and suppression of curling, preferably 0.6 or more and 1.4 or less, more preferably 0.7 or more and 1.3 or less, even more preferably 0.8 or more and 1.2 or less, and particularly preferably 0.9 or more and 1.1 or less.

[0124] <First Surface Resin Layer in Second Aspect, First and Second Surface Resin Layers in Third Aspect, and Second Surface Resin Layer in 4B Aspect> In the stretched substrate of the second embodiment, the first surface resin layer contains polyethylene and an adhesive resin. In the stretched substrate of the third embodiment, the first and second surface resin layers each independently contain polyethylene and an adhesive resin. In the stretched substrate of the fourth embodiment, the second surface resin layer contains polyethylene and an adhesive resin. The vapor deposition film provided on the surface of such a surface resin layer tends to have excellent adhesion to the surface resin layer and exhibit good gas barrier properties.

[0125] As the polyethylene, for example, high density polyethylene, medium density polyethylene, low density polyethylene and linear low density polyethylene are preferable, and from the viewpoint of the surface smoothness of the stretched substrate and the adhesion between the surface resin layer and the vapor deposition film, linear low density polyethylene is more preferable. Examples of the linear low density polyethylene include C4-LLDPE, C6-LLDPE and C8-LLDPE.

[0126] The melting point (Tm) of the polyethylene in the first surface resin layer of the stretched substrate of the second embodiment, the melting point (Tm) of the polyethylene in the first and second surface resin layers of the stretched substrate of the third embodiment, and the melting point (Tm) of the polyethylene in the second surface resin layer of the stretched substrate of the 4B embodiment are each independently, from the viewpoints of the strength and heat resistance of the stretched substrate and the adhesion between the surface resin layer and the vapor-deposited film, preferably 100°C or more, more preferably 105°C or more, even more preferably 110°C or more, particularly preferably 115°C or more, and preferably 140°C or less, for example, 100°C or more and 140°C or less.

[0127] Examples of the adhesive resin include acid-modified resin, silicone resin, epoxy resin and phenol resin, and acid-modified resin is preferred. Examples of the acid-modified resin include acid-modified polyolefin and acid-modified vinyl resin. Among these, from the viewpoint of recyclability and adhesion, acid-modified polyolefin is preferred, acid-modified polypropylene and acid-modified polyethylene are more preferred, acid-modified polyethylene is even more preferred, and acid-modified linear low-density polyethylene is even more preferred. The surface resin layer containing acid-modified linear low-density polyethylene tends to have better adhesion to the vapor deposition film.

[0128] Examples of acid-modified polyolefins include polyolefins (such as polypropylene and polyethylene) modified with an acid-modifying component, particularly graft-modified polyolefins with an acid-modifying component. Examples of acid-modified components include unsaturated carboxylic acids such as maleic acid, fumaric acid, acrylic acid, methacrylic acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, and methyltetrahydrophthalic acid, or their acid anhydrides, esters, or metal salts. Examples of acid-modified polyolefins include maleic acid-modified polyolefins and maleic anhydride-modified polyolefins, and more preferably maleic acid-modified polypropylene, maleic anhydride-modified polypropylene, maleic acid-modified polyethylene, and maleic anhydride-modified polyethylene.

[0129] The content of the structural unit derived from the acid-modified component in the acid-modified polyolefin is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, from the viewpoint of adhesion between the surface resin layer and the vapor deposition film. The content of the structural unit derived from the acid-modified component in the acid-modified polyolefin is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, from the viewpoint of adhesion between the surface resin layer and the polyethylene intermediate layer. The content is, for example, 0.01% by mass or more and 10% by mass or less. The content of the structural unit derived from the acid-modified component is measured by infrared spectroscopy.

[0130] From the viewpoint of film-forming and processability, the MFR of the acid-modified polyolefin is preferably 0.1 g / 10 min or more, more preferably 1 g / 10 min or more, even more preferably 1.5 g / 10 min or more, and preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, even more preferably 10 g / 10 min or less, for example, 0.1 g / 10 min or more and 50 g / 10 min or less. The MFR of the acid-modified polyolefin is measured by the A method under a load of 2.16 kg in accordance with JIS K7210-1:2014. The measurement temperature of the MFR is set according to the melting point of the acid-modified polyolefin, and is 230 ° C. for acid-modified polypropylene and 190 ° C. for acid-modified polyethylene.

[0131] The density of acid-modified polypropylene is, for example, 0.88 g / cm 3 More than 0.92g / cm 3 In this specification, the density of the acid-modified polypropylene is measured in accordance with Method D (density gradient tube method, 23° C.) of JIS K7112:1999. The density of the acid-modified polyethylene may be in the same range as that of the polyethylene described above.

[0132] The melting point (Tm) of the acid-modified polypropylene is, from the viewpoints of the strength and heat resistance of the stretched substrate, and the adhesion between the surface resin layer and the vapor-deposited film, preferably 120°C or higher, more preferably 125°C or higher, and even more preferably 130°C or higher; it is preferably 175°C or lower, more preferably 170°C or lower, even more preferably 165°C or lower, still more preferably 160°C or lower, particularly preferably 155°C or lower or 150°C or lower, for example, 120°C or higher and 175°C or lower.

[0133] The melting point (Tm) of the acid-modified polyethylene is, from the viewpoints of the strength and heat resistance of the stretched substrate and the adhesion between the surface resin layer and the vapor-deposited film, preferably 100°C or higher, more preferably 105°C or higher, even more preferably 110°C or higher, and particularly preferably 115°C or higher, and is preferably 140°C or lower, for example, 100°C or higher and 140°C or lower.

[0134] In the first surface resin layer of the stretched substrate of the second embodiment, in the first and second surface resin layers of the stretched substrate of the third embodiment, and in the second surface resin layer of the stretched substrate of the fourth embodiment, it is preferable that the polyethylene content is 60% by mass or more and 95% by mass or less, and the adhesive resin content is 5% by mass or more and 40% by mass or less, more preferably the polyethylene content is 70% by mass or more and 95% by mass or less, and the adhesive resin content is 5% by mass or more and 30% by mass or less, more preferably the polyethylene content is 80% by mass or more and 95% by mass or less, and the adhesive resin content is 5% by mass or more and 20% by mass or less, and it is particularly preferable that the polyethylene content is 85% by mass or more and 95% by mass or less, and the adhesive resin content is 5% by mass or more and 15% by mass or less. The surface resin layer of such an embodiment tends to be more excellent in surface smoothness, adhesion to the vapor deposition film, and adhesion to the polyethylene intermediate layer. When the content of the adhesive resin is equal to or less than the upper limit, for example, it is possible to prevent the film from adhering more than necessary to a roll or the like during production of a stretched substrate.

[0135] The surface resin layer may contain linear low-density polyethylene as a main component from the viewpoints of biaxial stretchability, surface smoothness, etc. Details of the linear low-density polyethylene are as described above in the section on the polyethylene layer (1), and therefore will not be described here.

[0136] In one embodiment, the surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, and preferably contains high density polyethylene. Therefore, the stretched substrate having such a surface resin layer has high heat resistance, specifically, excellent resistance to drying during printing and heating during heat sealing, and excellent resistance to deposition when deposition is performed on the film. In addition, the surface resin layer has high rigidity, and can increase the film conveying speed when deposition is performed on the film, thereby increasing productivity.

[0137] The details of the high density polyethylene and the medium density polyethylene are as described above in the section on the polyethylene layer (1), and therefore the description will be omitted here. As the high density polyethylene and the medium density polyethylene, the above-mentioned ethylene-α-olefin copolymers are preferable.

[0138] In 100% by mass of polyethylene contained in the above-mentioned surface resin layer, the content of linear low-density polyethylene may be 60% by mass or more, 65% by mass or more, 70% by mass or more, 100% by mass or less, 95% by mass or less, 90% by mass or less, 85% by mass or less, or 80% by mass or less, for example, 60% by mass or more and 100% by mass or less.

[0139] The total content of high-density polyethylene and medium-density polyethylene in 100% by mass of polyethylene contained in the surface resin layer may be 0% by mass or more, 5% by mass or more, 10% by mass or more, 15% by mass or more, 20% by mass or more, 40% by mass or less, 35% by mass or less, or 30% by mass or less, for example, 0% by mass or more and 40% by mass or less.

[0140] The polyethylene contained in the surface resin layer is 0.930 g / cm 3 Super 0.960g / cm 3 It may have a density of 0.931 g / cm 3 More than 0.955g / cm 3 Less than or equal to 0.931 g / cm 3 More than 0.950g / cm 3 When the surface resin layer contains two or more types of polyethylene having different densities, the density of the polyethylene means the density of a mixture of two or more types of polyethylene.

[0141] The surface resin layer may contain the above-mentioned resin materials other than the above-mentioned components. The surface resin layer may contain the additive.

[0142] The thickness of the first surface resin layer in the stretched substrate of the second embodiment, the thickness of the first and second surface resin layers in the stretched substrate of the third embodiment, and the thickness of the second surface resin layer in the stretched substrate of the 4B embodiment are each independently, from the viewpoint of better exerting the above-mentioned effects, preferably 0.3 μm or more, more preferably 0.5 μm or more, even more preferably 0.8 μm or more, and preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, particularly preferably 3 μm or less, for example, 0.3 μm or more and 15 μm or less.

[0143] The thickness of the first surface resin layer in the stretched substrate of the second embodiment, the thickness of the first and second surface resin layers in the stretched substrate of the third embodiment, and the thickness of the second surface resin layer in the stretched substrate of the 4B embodiment are each independently, relative to the thickness of the stretched substrate, preferably 1% or more, more preferably 2% or more, even more preferably 4% or more, and preferably 20% or less, more preferably 15% or less, even more preferably 10% or less, particularly preferably 8% or less, for example, 1% or more and 20% or less.

[0144] <First Surface Resin Layer in the Fourth Aspect> In the stretched substrate of the fourth embodiment, the first surface resin layer contains polyethylene as a main component. In the stretched substrate of the fourth embodiment, the content of polyethylene in the first surface resin layer is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0145] In the stretched substrate of the fourth embodiment, the layer containing polyethylene as a main component in the first surface resin layer may be, for example, the same layer as the above-mentioned <polyethylene intermediate layer>. For example, the first surface resin layer may be the above-mentioned polyethylene layer (1) or (2).

[0146] The first surface resin layer may contain the above-mentioned resin materials other than polyethylene. The first surface resin layer may contain an upper additive.

[0147] In the stretched substrate of the fourth embodiment, the thickness of the first surface resin layer is, from the viewpoint of better exerting the above-mentioned effects, preferably 0.3 μm or more, more preferably 0.5 μm or more, even more preferably 0.8 μm or more, and is preferably 15 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, particularly preferably 3 μm or less, for example, 0.3 μm or more and 15 μm or less.

[0148] In the stretched substrate of the fourth embodiment, the thickness of the first surface resin layer is preferably 1% or more, more preferably 2% or more, even more preferably 4% or more, and is preferably 20% or less, more preferably 15% or less, even more preferably 10% or less, particularly preferably 8% or less, for example, 1% or more and 20% or less, relative to the thickness of the stretched substrate.

[0149] The first surface resin layer and / or the second surface resin layer in the stretched substrate of each of the above-mentioned embodiments may further contain particles. When the surface resin layer contains particles, for example, the antiblocking property or slipping property of the stretched substrate can be improved.

[0150] Examples of the particles include inorganic compound-based antiblocking agents and resin particle-based antiblocking agents. Specific examples of the inorganic compound-based antiblocking agents include oxides such as silica, aluminum oxide, magnesium oxide, calcium oxide, titanium oxide, and zinc oxide, hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide, carbonates such as magnesium carbonate and calcium carbonate, sulfates such as calcium sulfate and barium sulfate, silicates such as magnesium silicate, aluminum silicate, calcium silicate, and aluminosilicate, and other compounds such as kaolin, talc, and diatomaceous earth. Specific examples of the resin particles include resin particles made of resin components such as polymethyl methacrylate (PMMA), polystyrene, methyl methacrylate-styrene copolymer, polyester, polyamide, polytetrafluoroethylene, epoxy resin, urea resin, and phenol resin. The resin particles may be crosslinked or non-crosslinked.

[0151] From the viewpoint of cost etc., the particles may be an inorganic compound-based antiblocking agent. The particles may be a resin particle-based antiblocking agent. This reduces the possibility that the particles will damage the vapor-deposited film when the substrate is stored in a roll shape, for example, in the case of a barrier substrate having one surface resin layer containing a resin particle-based antiblocking agent and the other surface resin layer having a vapor-deposited film, as described below. This is because the resin particle-based antiblocking agent is usually smaller in unevenness and softer than the inorganic compound-based antiblocking agent.

[0152] The average particle size of the particles is preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 2 μm or more, and preferably 6 μm or less, more preferably 5.5 μm or less, even more preferably 5 μm or less, for example, 0.5 μm or more and 6 μm or less. The average particle size of the particles means the average particle size (arithmetic mean diameter) measured for non-aggregates of 100 randomly selected particles by observing the cross section in the thickness direction of each layer with a scanning electron microscope (SEM).

[0153] When the first surface resin layer contains particles, the particle content, based on the mass of the first surface resin layer, is preferably 100 ppm or more, more preferably 500 ppm or more, even more preferably 1,000 ppm or more, and is preferably 10,000 ppm or less, more preferably 8,000 ppm or less, even more preferably 5,000 ppm or less, for example, 100 ppm or more and 10,000 ppm or less.

[0154] When the second surface resin layer contains particles, the content of the particles is, based on the mass of the second surface resin layer, preferably 100 ppm or more, more preferably 500 ppm or more, even more preferably 1,000 ppm or more, and preferably 10,000 ppm or less, more preferably 8,000 ppm or less, even more preferably 5,000 ppm or less, for example, 100 ppm or more and 10,000 ppm or less.

[0155] When a vapor-deposited film is provided on the surface resin layer, from the viewpoint of formability of the vapor-deposited film, it is preferable that the surface resin layer on which the vapor-deposited film is provided does not contain particles.

[0156] When the surface resin layer contains particles, the ratio of the average particle size of the particles to the thickness of the surface resin layer (average particle size / thickness) is preferably 0.5 to 5.0, more preferably 0.8 to 4.0, and even more preferably 1.0 to 3.5. The surface resin layer here may be a first surface resin layer, a second surface resin layer, or both.

[0157] In the stretched substrate of each of the above embodiments, when any adjacent layers selected from the polyethylene intermediate layer, the surface resin layer containing polyethylene as a main component, and the surface resin layer containing polyethylene and an adhesive resin are referred to as layer (i) and layer (ii), the absolute value of the difference between the density of the polyethylene constituting layer (i) and the density of the polyethylene constituting layer (ii) is preferably 0.030 g / cm. 3 Less than or equal to 0.025 g / cm 3 More preferably, 0.020 g / cm3 Less than 0.010 g / cm 3 Such a film has excellent interlayer adhesion, for example, excellent drop resistance.

[0158] In one embodiment of the stretched substrate, the density of the polyethylene in the polyethylene intermediate layer is higher than the density of the polyethylene in the first surface resin layer, and, if desired, the density of the polyethylene in the second surface resin layer is lower than the density of the polyethylene in the polyethylene intermediate layer. Such a stretched substrate tends to have an excellent balance of surface smoothness, transparency, printability, vapor deposition adhesion, and heat resistance. When the polyethylene intermediate layer is thicker than the surface resin layer, high heat resistance is obtained by the polyethylene intermediate layer. The difference in density of the polyethylene between the polyethylene intermediate layer and the surface resin layer is, for example, 0.003 g / cm. 3 More than that is fine. The total content ratio of the high density polyethylene and the medium density polyethylene is hereinafter referred to as "content ratio A." Herein, only high density polyethylene may be used, only medium density polyethylene may be used, or a mixture of high density polyethylene and medium density polyethylene may be used. In one embodiment of the stretched substrate, the content ratio A in the polyethylene intermediate layer is greater than the content ratio A in the first surface resin layer, and, if desired, the content ratio A in the second surface resin layer is smaller than the content ratio A in the polyethylene intermediate layer. Such a stretched substrate tends to have an excellent balance of surface smoothness, transparency, printability, vapor deposition adhesion, and heat resistance. The difference in content ratio A between the polyethylene intermediate layer and the surface resin layer may be, for example, 10% by mass or more, 50% by mass or less, 40% by mass or less, or 30% by mass or less.

[0159] In one embodiment of the stretched substrate, the density of the polyethylene in the polyethylene intermediate layer is lower than the density of the polyethylene in the first surface resin layer, and, if desired, the density of the polyethylene in the second surface resin layer is higher than the density of the polyethylene in the polyethylene intermediate layer. Such a stretched substrate tends to have an excellent balance between biaxial stretchability and heat resistance. When the polyethylene intermediate layer is thicker than the surface resin layer, high biaxial stretchability is obtained by the polyethylene intermediate layer. The density difference between the polyethylene in the surface resin layer and the polyethylene intermediate layer is, for example, 0.003 g / cm. 3 More than that is fine. In one embodiment of the stretched substrate, the content ratio A in the polyethylene intermediate layer is smaller than the content ratio A in the first surface resin layer, and, if desired, the content ratio A in the second surface resin layer is larger than the content ratio A in the polyethylene intermediate layer. Such a stretched substrate tends to have an excellent balance between biaxial stretchability and heat resistance. The difference in content ratio A between the surface resin layer and the polyethylene intermediate layer may be, for example, 10% by mass or more, 50% by mass or less, 40% by mass or less, or 30% by mass or less.

[0160] In one embodiment of the stretched substrate, the first surface resin layer, the polyethylene intermediate layer, and optionally the second surface resin layer each have a substantially equal density of polyethylene. For example, the difference in density between the layer with the highest polyethylene density and the layer with the lowest polyethylene density among the first surface resin layer, the polyethylene intermediate layer, and optionally the second surface resin layer is 0.003 g / cm 3 is less than. In one embodiment of the stretched substrate, the first surface resin layer, the polyethylene intermediate layer, and the optional second surface resin layer each have approximately the same content ratio A. For example, the difference in content ratio A between the layer having the highest content ratio A and the layer having the lowest content ratio A among the first surface resin layer, the polyethylene intermediate layer, and the optional second surface resin layer is less than 10% by mass.

[0161] In addition, when each layer contains two or more kinds of polyethylene having different densities, the density of the polyethylene means the density of a mixture of two or more kinds of polyethylene. The method of measuring and calculating the density is as described above.

[0162] <Adhesive resin layer> The stretched substrate of the first embodiment may further include a first adhesive resin layer between the first surface resin layer and the polyethylene intermediate layer. The stretched substrate of the first embodiment may further include a second adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. Such a stretched substrate has, for example, excellent adhesion between the polyethylene intermediate layer and the surface resin layer. The stretched substrate of the second embodiment and the fourth embodiment may further include an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. Such a stretched substrate has, for example, excellent adhesion between the polyethylene intermediate layer and the second surface resin layer.

[0163] The adhesive resin layer contains an adhesive resin as a main component. Examples of the adhesive resin include acid-modified resin, silicone resin, epoxy resin, and phenol resin, and acid-modified resin is preferred. Examples of the acid-modified resin include acid-modified polyolefin and acid-modified vinyl resin. Among these, acid-modified polyolefin is preferred, acid-modified polypropylene and acid-modified polyethylene are more preferred, acid-modified polyethylene is even more preferred, and acid-modified linear low-density polyethylene is even more preferred. Details of acid-modified polyolefin (structure, physical properties such as MFR, density, and Tm) are as described in the section <First surface resin layer in the second embodiment...>, and description here is omitted.

[0164] The content of the adhesive resin in the adhesive resin layer is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more.

[0165] The adhesive resin layer may contain the above-mentioned additives.

[0166] In the stretched substrate of the first embodiment, the thicknesses of the first and second adhesive resin layers are each independently preferably 0.5 μm or more, more preferably 0.8 μm or more, and even more preferably 1 μm or more, from the viewpoint of adhesiveness. In the stretched substrate of the first embodiment, the thicknesses of the first and second adhesive resin layers are each independently preferably 18 μm or less, more preferably 13 μm or less, even more preferably 8 μm or less, and particularly preferably 5 μm or less, from the viewpoint of recyclability of the stretched substrate and the barrier substrate. The thicknesses of the first and second adhesive resin layers are, for example, 0.5 μm or more and 18 μm or less.

[0167] In the stretched substrate of the first embodiment, the thickness of the first and second adhesive resin layers is, independently of each other, preferably 2% or more, more preferably 4% or more, even more preferably 6% or more, and preferably 25% or less, more preferably 20% or less, even more preferably 15% or less, particularly preferably 10% or less, for example, 2% or more and 25% or less, relative to the thickness of the stretched substrate.

[0168] The stretched substrate of the first embodiment may include a first surface resin layer, a first adhesive resin layer, a polyethylene intermediate layer, a second adhesive resin layer, and a second surface resin layer in this order. In the stretched substrate including the first surface resin layer, the first adhesive resin layer, the polyethylene intermediate layer, the second adhesive resin layer, and the second surface resin layer in this order, the ratio of the thickness of the first adhesive resin layer to the thickness of the second adhesive resin layer is preferably 0.6 to 1.4, more preferably 0.7 to 1.3, even more preferably 0.8 to 1.2, and particularly preferably 0.9 to 1.1, from the viewpoint of symmetry of the stretched substrate and suppression of curling.

[0169] In the stretched substrate of the second embodiment and the fourth embodiment, the thickness of the adhesive resin layer is preferably 0.5 μm or more, more preferably 0.8 μm or more, and even more preferably 1 μm or more, from the viewpoint of adhesiveness. In the stretched substrate of the second embodiment and the fourth embodiment, the thickness of the adhesive resin layer is preferably 18 μm or less, more preferably 13 μm or less, even more preferably 8 μm or less, and particularly preferably 5 μm or less, from the viewpoint of recyclability of the stretched substrate and the barrier substrate. The thickness of the adhesive resin layer is, for example, 0.5 μm or more and 18 μm or less.

[0170] In the stretched substrates of the second and fourth A embodiments, the thickness of the adhesive resin layer is preferably 2% or more, more preferably 4% or more, even more preferably 6% or more, and is preferably 25% or less, more preferably 20% or less, even more preferably 15% or less, particularly preferably 10% or less, for example, 2% or more and 25% or less, relative to the thickness of the stretched substrate.

[0171] <Gas barrier properties of stretched substrate> The oxygen permeability (unit: cc / (m 2 ·day·atm) is preferably less than 30, more preferably less than 25, even more preferably less than 18, still more preferably less than 10, and particularly preferably less than 5.0. The oxygen permeability is measured in accordance with JIS K7126-2:2006 in an environment at a temperature of 23°C and a humidity of 90% RH.

[0172] The water vapor permeability (unit: g / (m 2 ·day)) is preferably less than 20, more preferably less than 15, even more preferably less than 10, still more preferably less than 8.0, and particularly preferably less than 5.0. The water vapor permeability is measured in accordance with JIS K7129-2:2019 at a temperature of 40°C and a humidity of 90% RH.

[0173] [Barrier substrate] The barrier substrate according to the first embodiment of the present disclosure comprises: The stretched substrate according to the first aspect described above, a vapor-deposited film provided on the surface of at least one layer selected from the first surface resin layer and the second surface resin layer of the stretched substrate; Equipped with.

[0174] The barrier substrate according to the second embodiment of the present disclosure comprises: The stretched substrate according to the second aspect described above, a vapor-deposited film provided on the surface of at least one layer selected from the first surface resin layer and the second surface resin layer of the stretched substrate; Equipped with.

[0175] The barrier substrate according to the third embodiment of the present disclosure comprises: The stretched substrate according to the third aspect described above, a vapor-deposited film provided on the surface of at least one layer selected from the first surface resin layer and the second surface resin layer of the stretched substrate; Equipped with.

[0176] The barrier substrate according to the fourth embodiment of the present disclosure comprises: The stretched substrate according to the fourth aspect described above, a deposition film provided on a surface of the second surface resin layer of the stretched substrate; Equipped with.

[0177] In the barrier substrate of the first, second and third embodiments, the vapor-deposited film may be provided only on the surface of the first surface resin layer of the stretched substrate, may be provided only on the surface of the second surface resin layer, or may be provided on the surfaces of the first surface resin layer and the second surface resin layer.

[0178] When describing matters common to the barrier substrates of the first to fourth embodiments, or when there is no particular distinction between the barrier substrates of the first to fourth embodiments, they are also simply referred to as "barrier substrate".

[0179] In one embodiment, the barrier substrate of the present disclosure comprises: A first vapor-deposited film; The stretched substrate described above; A second deposited film; In the thickness direction, at least

[0180] The stretched substrate has a first surface and a second surface opposite to the first surface. In one embodiment, the first surface resin layer constitutes the first surface, and the second surface resin layer constitutes the second surface. The first vapor-deposited film is provided on the first surface of the stretched substrate. The first vapor-deposited film is provided on the surface of the first surface resin layer of the stretched substrate. The second vapor-deposited film is provided on the second surface of the stretched substrate. The second vapor-deposited film is provided on the surface of the second surface resin layer of the stretched substrate.

[0181] The barrier substrate may further include a printed layer, which will be described later.

[0182] <Vapor deposition film> The barrier substrate of the present disclosure has a vapor deposition film and is excellent in gas barrier properties. Therefore, a packaging container produced using such a barrier substrate has excellent gas barrier properties. In one embodiment, the barrier substrate of the present disclosure has a first vapor deposition film and a second vapor deposition film and is more excellent in gas barrier properties. Since such a barrier substrate has vapor deposition films on both sides of the stretched substrate, it is possible to suppress the deterioration of gas barrier properties due to pinholes.

[0183] The vapor deposition film is composed of, for example, a metal and / or an inorganic oxide. The vapor deposition film may be a metal vapor deposition film composed of one or more metals, or an inorganic oxide vapor deposition film composed of one or more inorganic oxides. The inorganic oxide vapor deposition film may be a transparent vapor deposition film. Examples of metals include aluminum, chromium, tin, nickel, copper, silver, gold, and platinum. Examples of inorganic oxides include aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, barium oxide, and silicon carbide oxide (carbon-containing silicon oxide). Among the vapor deposition films, aluminum vapor deposition films, aluminum oxide (alumina) vapor deposition films, silicon oxide (silica) vapor deposition films, and silicon carbide oxide vapor deposition films are preferred, and the first vapor deposition film and the second vapor deposition film are each independently preferably an aluminum vapor deposition film, an aluminum oxide (alumina) vapor deposition film, a silicon oxide (silica) vapor deposition film, or a silicon carbide oxide vapor deposition film.

[0184] The combination of the first and second evaporated films is not particularly limited. The first vapor-deposited film may be a metal vapor-deposited film and the second vapor-deposited film may be a metal vapor-deposited film, where both may be the same or different. One of the first vapor-deposited film and the second vapor-deposited film may be a metal vapor-deposited film and the other may be an inorganic oxide vapor-deposited film or a transparent vapor-deposited film. The first vapor-deposited film may be an inorganic oxide vapor-deposited film or a transparent vapor-deposited film, where both may be the same or different.

[0185] In one embodiment, the first vapor-deposited film is a metal vapor-deposited film, and the second vapor-deposited film is a metal vapor-deposited film, which may be the same or different. Such a barrier substrate has particularly excellent gas barrier properties.

[0186] For example, when a packaging container is produced using a laminate comprising a barrier substrate having a metal vapor deposition film such as an aluminum vapor deposition film on both sides of a stretched substrate, depending on the type of contents filled in the packaging container, the metal vapor deposition film may be oxidized to form a metal oxide, causing discoloration, corrosion, or volume expansion, reducing the laminate strength, and causing problems such as lifting and peeling of layers.

[0187] In one embodiment, at least one of the first and second vapor deposition films is an inorganic oxide vapor deposition film. By using a laminate including such a barrier substrate, a packaging container having excellent resistance to contents can be produced. For example, a laminate including a barrier substrate and a heat seal layer is prepared. The laminate includes a barrier substrate arranged such that the inorganic oxide vapor deposition film faces the heat seal layer side (inside of the packaging container) and the other vapor deposition film faces the outside (outside of the packaging container). When both the first and second vapor deposition films are inorganic oxide vapor deposition films, the orientation of the barrier substrate is not particularly limited. By producing a packaging container using the above laminate, discoloration, corrosion or deterioration of the vapor deposition film, and lifting or peeling of layers can be suppressed even when the packaging container is filled with corrosive contents. This is because the inorganic oxide vapor deposition film is originally oxidized, and thus it is possible to suppress the occurrence of volume expansion due to oxidation, as occurs with metal vapor deposition films.

[0188] In one embodiment, the first vapor-deposited film is an inorganic oxide vapor-deposited film and the second vapor-deposited film is a metal vapor-deposited film. In one embodiment, the first vapor-deposited film is a metal vapor-deposited film and the second vapor-deposited film is an inorganic oxide vapor-deposited film. The inorganic oxide vapor-deposited film may be a transparent vapor-deposited film.

[0189] In one embodiment, the first vapor-deposition film is an inorganic oxide vapor-deposition film, and the second vapor-deposition film is an inorganic oxide vapor-deposition film. Here, both may be the same or different. The inorganic oxide vapor-deposition film may be a transparent vapor-deposition film. Such a barrier substrate can avoid the problem of oxidation deterioration when the vapor-deposition film is a metal vapor-deposition film, and can also suppress corrosion of the vapor-deposition film from the end face of the barrier substrate. In addition, since such a barrier substrate has excellent transparency, a packaging container with excellent visibility of the contents can be produced, for example, a packaging container that can be used in a microwave oven and a packaging container that can pass through a metal detector can be produced. In addition, a packaging container including such a barrier substrate can be clearly understood by, for example, a consumer that does not contain an aluminum vapor-deposition film, making it easy to separate, and further, can suppress the inclusion of foreign matter such as black spots (metal color) that may occur due to the aluminum vapor-deposition film during recycling processing.

[0190] In one embodiment, the barrier substrate of the present disclosure has a vapor-deposited film only on one surface of the stretched substrate. In one embodiment, the barrier substrate of the present disclosure has a vapor-deposited film only on the surface of the second surface resin layer of the stretched substrate, and does not have a vapor-deposited film on the surface of the first surface resin layer. By using a laminate having such a barrier substrate, a packaging container having excellent content resistance can be produced. For example, a laminate having a barrier substrate and a heat seal layer is prepared. The laminate has a barrier substrate arranged such that the stretched substrate faces the heat seal layer side (inside of the packaging container) and the vapor-deposited film faces the outside (outside of the packaging container). By producing a packaging container using the above laminate, the vapor-deposited film can be arranged on the outside, so that even if a corrosive content is filled in the packaging container, discoloration, corrosion or deterioration of the vapor-deposited film and lifting or peeling of the layer can be suppressed.

[0191] The first and second vapor-deposited films may both be aluminum vapor-deposited films, and may be the same or different. One of the first and second vapor-deposited films may be an alumina vapor-deposited film, a silica vapor-deposited film, or a silicon carbide oxide vapor-deposited film, and the other may be an aluminum vapor-deposited film. The first vapor-deposited film may be an alumina vapor-deposited film, a silica vapor-deposited film, or a silicon carbide oxide vapor-deposited film, and the second vapor-deposited film may be an alumina vapor-deposited film, a silica vapor-deposited film, or a silicon carbide oxide vapor-deposited film, and may be the same or different.

[0192] The thickness of the vapor-deposited film is preferably 1 nm or more, more preferably 5 nm or more, and even more preferably 10 nm or more, from the viewpoint of gas barrier properties. The thickness of the vapor-deposited film is preferably 150 nm or less, more preferably 100 nm or less, and even more preferably 80 nm or less, from the viewpoint of suppressing crack generation in the vapor-deposited film and recyclability of the packaging container. The thickness of the vapor-deposited film is, for example, 1 nm or more and 150 nm or less. The thicknesses of the first vapor-deposited film and the second vapor-deposited film are also preferably independently within the above range.

[0193] When the vapor deposition film is an aluminum vapor deposition film, the optical density (OD value) of the aluminum vapor deposition film is preferably 2.0 or more and 3.5 or less, more preferably 2.2 or more and 3.5 or less, even more preferably 2.7 or more and 3.5 or less, and particularly preferably 3.0 or more and 3.5 or less. This can improve the oxygen barrier property and water vapor barrier property while maintaining the productivity of the barrier substrate. When one vapor deposition film in the barrier substrate of the present disclosure is a transparent vapor deposition film, the other vapor deposition film tends to have a stable OD value and an aluminum vapor deposition film with excellent thickness uniformity. The OD value can be measured in accordance with JIS K7361-1:1997.

[0194] The surface of the deposited film is preferably subjected to the above-mentioned surface treatment, so that such a deposited film has, for example, excellent adhesion to adjacent layers.

[0195] Examples of methods for forming the vapor-deposited film include physical vapor deposition methods (PVD methods) such as vacuum deposition, sputtering, and ion plating, and chemical vapor deposition methods (CVD methods) such as plasma chemical vapor deposition, thermal chemical vapor deposition, and photochemical vapor deposition. The vapor-deposited film may be a composite film containing two or more layers of different vapor-deposited films formed by combining both physical vapor deposition and chemical vapor deposition.

[0196] The vacuum level in the deposition chamber was 10 before oxygen was introduced. -2 ~10 -8 After oxygen is introduced, the pressure is preferably about 10 -1 ~10 -6 The pressure is preferably about mbar. The amount of oxygen introduced varies depending on the size of the deposition machine. For the oxygen introduced, an inert gas such as argon gas, helium gas, or nitrogen gas may be used as a carrier gas to the extent that no problems occur. The conveying speed of the target film on which the deposition film is formed is, for example, 10 m / min or more and 800 m / min or less.

[0197] The vapor-deposited film may be a single layer formed by one vapor deposition process, or may be a multilayer formed by multiple vapor deposition processes. When the vapor-deposited film is a multilayer film, each layer may be composed of the same component or different components. Each layer may be formed by the same method or different methods.

[0198] In one embodiment, the stretched substrate comprises a first surface resin layer constituting the first surface and a second surface resin layer constituting the second surface, the first vapor-deposited film is provided on the surface of the first surface resin layer, and the second vapor-deposited film is provided on the surface of the second surface resin layer. Such a stretched substrate is excellent in, for example, vapor-deposited film formability, smoothness, and adhesion, and the obtained barrier substrate is excellent in, for example, gas barrier properties, specifically oxygen barrier properties and water vapor barrier properties, and also excellent in brightness when the vapor-deposited film is a metal vapor-deposited film.

[0199] In one embodiment, the stretched substrate comprises a first surface resin layer constituting the first surface and a second surface resin layer constituting the second surface, and the vapor deposition film is provided on the surface of the second surface resin layer. Such a stretched substrate is excellent in, for example, vapor deposition film formability, smoothness and adhesion, and the obtained barrier substrate is excellent in, for example, gas barrier property, specifically oxygen barrier property and water vapor barrier property, and when the vapor deposition film is a metal vapor deposition film, it is excellent in brightness.

[0200] <Barrier coat layer> The barrier substrate of the present disclosure may further include a barrier coat layer on the vapor-deposited film. That is, the barrier substrate may further include a barrier coat layer on the surface of the vapor-deposited film opposite to the surface of the stretched substrate. Such a barrier substrate has, for example, excellent oxygen barrier properties and water vapor barrier properties, and can effectively suppress the occurrence of cracks in the vapor-deposited film when the vapor-deposited film is made of an inorganic oxide such as aluminum oxide or silicon oxide.

[0201] In one embodiment, the barrier substrate comprises, in this order, a metal vapor deposition film as a first vapor deposition film, a first surface resin layer, a polyethylene intermediate layer, a second surface resin layer, an inorganic oxide vapor deposition film as a second vapor deposition film, and a barrier coat layer. In one embodiment, the barrier substrate comprises, in this order, a barrier coat layer, an inorganic oxide vapor deposition film as a first vapor deposition film, a first surface resin layer, a polyethylene intermediate layer, a second surface resin layer, and a metal vapor deposition film as a second vapor deposition film. In one embodiment, the barrier substrate comprises, in this order, a first barrier coating layer, an inorganic oxide vapor deposition film as a first vapor deposition film, a first surface resin layer, a polyethylene intermediate layer, a second surface resin layer, an inorganic oxide vapor deposition film as a second vapor deposition film, and a second barrier coating layer. In one embodiment, the barrier substrate comprises, in this order, a first surface resin layer, a polyethylene intermediate layer, a second surface resin layer, an inorganic oxide vapor deposition film, and a barrier coat layer.

[0202] In one embodiment, the barrier coat layer contains a gas barrier resin, such as an ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyamide, polyvinylidene chloride, polyester, polyether polyol, polyester polyol, polyurethane, polyacrylonitrile, or (meth)acrylic resin.

[0203] The content of the gas barrier resin in the barrier coat layer is preferably more than 50% by mass, more preferably 60% by mass or more, and even more preferably 70% by mass or more. Such a barrier coat layer has, for example, excellent gas barrier properties.

[0204] The barrier coat layer may contain the above-mentioned additives.

[0205] The thickness of the barrier coat layer containing the gas barrier resin is preferably 0.01 μm or more, more preferably 0.1 μm or more, from the viewpoint of gas barrier properties. The thickness of the barrier coat layer containing the gas barrier resin is preferably 10 μm or less, more preferably 5 μm or less, from the viewpoint of processability of the barrier substrate and recyclability of the packaging container. The thickness is, for example, 0.01 μm or more and 10 μm or less.

[0206] The barrier coat layer can be formed, for example, by applying a coating liquid obtained by dissolving or dispersing a material such as a gas barrier resin in water or an appropriate organic solvent onto the vapor-deposited film, and drying the resulting coating liquid.

[0207] In another embodiment, the barrier coat layer is a gas barrier coating film formed by mixing a metal alkoxide, a water-soluble polymer, and optionally a silane coupling agent, and adding water, an organic solvent, and a sol-gel catalyst as required to obtain a gas barrier composition, coating the gas barrier composition on a deposition film, and drying the gas barrier composition. The gas barrier coating film contains a hydrolysis polycondensate obtained by hydrolyzing and polycondensing the above-mentioned metal alkoxide by the sol-gel method. By providing such a barrier coat layer on a deposition film, when the deposition film is made of an inorganic oxide, the gas barrier property can be improved and the occurrence of cracks in the deposition film can be effectively suppressed.

[0208] Examples of metal alkoxides include alkoxysilanes, specifically tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane.

[0209] Examples of the water-soluble polymer include hydroxyl group-containing polymers such as polyvinyl alcohol and ethylene-vinyl alcohol copolymer. Either polyvinyl alcohol or ethylene-vinyl alcohol copolymer may be used, or both may be used in combination, depending on the desired physical properties such as oxygen barrier property, water vapor barrier property, water resistance, and weather resistance. Also, a gas barrier coating film obtained using polyvinyl alcohol and a gas barrier coating film obtained using ethylene-vinyl alcohol copolymer may be laminated. The amount of the water-soluble polymer used is preferably 5 parts by mass or more and 500 parts by mass or less, based on 100 parts by mass of the metal alkoxide.

[0210] As the silane coupling agent, known organic reactive group-containing organoalkoxysilane can be used, and organoalkoxysilane having epoxy group is preferable, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane can be mentioned. The amount of the silane coupling agent used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the metal alkoxide.

[0211] The gas barrier composition may contain water in a ratio of preferably 0.1 mol or more, more preferably 0.5 mol or more, and preferably 100 mol or less, more preferably 60 mol or less, per mol of metal alkoxide. By making the water content equal to or greater than the lower limit, for example, the oxygen barrier property and water vapor barrier property of the barrier substrate can be improved. By making the water content equal to or less than the upper limit, for example, the hydrolysis reaction can be carried out quickly.

[0212] The gas barrier composition may contain an organic solvent, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, or n-butyl alcohol.

[0213] The sol-gel catalyst is preferably an acid or an amine compound.

[0214] Examples of methods for applying the gas barrier composition include application means such as roll coating using a gravure roll coater or the like, spray coating, spin coating, dipping, brush coating, bar coating, and applicator coating.

[0215] Hereinafter, one embodiment of the method for forming a gas barrier coating film will be described. A gas barrier composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and, if necessary, a silane coupling agent. A polycondensation reaction gradually proceeds in the composition. The composition is applied to the deposition film by a conventional method and dried. This drying causes further polycondensation of the metal alkoxide and the water-soluble polymer (and the silane coupling agent if the composition contains a silane coupling agent) to form a composite polymer layer. The above operation may be repeated to laminate multiple composite polymer layers. For example, the applied composition is heated at a temperature of preferably 20°C or higher, more preferably 50°C or higher, and even more preferably 70°C or higher, and preferably 150°C or lower, more preferably 120°C or lower, and even more preferably 100°C or lower, for 1 second to 10 minutes. This allows the formation of a gas barrier coating film.

[0216] The thickness of the gas barrier coating film is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, and is preferably 100 μm or less, more preferably 50 μm or less, even more preferably 5 μm or less, still more preferably 2 μm or less, particularly preferably 1 μm or less, for example, 0.01 μm or more and 100 μm or less. A barrier substrate provided with such a gas barrier coating film has, for example, excellent gas barrier properties, can suppress the occurrence of cracks in a vapor deposition film composed of an inorganic oxide, and also has excellent recyclability and processability of a packaging container.

[0217] <Layer structure of barrier substrate> Hereinafter, several examples of the layer structure of the barrier substrate of the present disclosure will be given with reference to the drawings. In these drawings, the layer structure of the stretched substrate of the present disclosure will also be described. 1A comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a polyethylene intermediate layer 10, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, the polyethylene intermediate layer 10, and the second surface resin layer 22. 1B comprises, in this order, a first surface resin layer 20, a polyethylene intermediate layer 10, a second surface resin layer 22, and a vapor-deposited film 40. The stretched substrate comprises, in this order, the first surface resin layer 20, the polyethylene intermediate layer 10, and the second surface resin layer 22. 2A comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a first adhesive resin layer 30, a polyethylene intermediate layer 10, a second adhesive resin layer 32, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, the first adhesive resin layer 30, the polyethylene intermediate layer 10, the second adhesive resin layer 32, and the second surface resin layer 22. 2B comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a polyethylene intermediate layer 10, an adhesive resin layer 30, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, a polyethylene intermediate layer 10, an adhesive resin layer 30, and a second surface resin layer 22. 2C comprises, in this order, a first surface resin layer 20, a polyethylene intermediate layer 10, an adhesive resin layer 30, a second surface resin layer 22, and a vapor-deposited film 40. The stretched substrate comprises, in this order, a first surface resin layer 20, a polyethylene intermediate layer 10, an adhesive resin layer 30, and a second surface resin layer 22. 2D comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a first polyethylene layer 11, a second polyethylene layer 12, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, the first polyethylene layer 11, the second polyethylene layer 12, and a second surface resin layer 22. 2E includes, in this order, a first surface resin layer 20, a first polyethylene layer 11, a second polyethylene layer 12, a third polyethylene layer 13, a second surface resin layer 22, and a vapor-deposited film 40. The stretched substrate includes, in this order, the first surface resin layer 20, the first polyethylene layer 11, the second polyethylene layer 12, the third polyethylene layer 13, and the second surface resin layer 22. 3A comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a first adhesive resin layer 30, a first polyethylene layer 11, a second polyethylene layer 12, a second adhesive resin layer 32, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, the first adhesive resin layer 30, the first polyethylene layer 11, the second polyethylene layer 12, the second adhesive resin layer 32, and the second surface resin layer 22. 3B comprises, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a first polyethylene layer 11, a second polyethylene layer 12, an adhesive resin layer 30, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate comprises, in this order, the first surface resin layer 20, the first polyethylene layer 11, the second polyethylene layer 12, an adhesive resin layer 30, and a second surface resin layer 22. 3C includes, in this order, a first vapor-deposited film 40, a first surface resin layer 20, a first polyethylene layer 11, a second polyethylene layer 12, a third polyethylene layer 13, a second surface resin layer 22, and a second vapor-deposited film 42. The stretched substrate includes, in this order, the first surface resin layer 20, the first polyethylene layer 11, the second polyethylene layer 12, the third polyethylene layer 13, and the second surface resin layer 22. 3D comprises, in this order, a first surface resin layer 20, a first polyethylene layer 11, a second polyethylene layer 12, an adhesive resin layer 30, a second surface resin layer 22, and a vapor-deposited film 40. The stretched substrate comprises, in this order, the first surface resin layer 20, the first polyethylene layer 11, the second polyethylene layer 12, the adhesive resin layer 30, and the second surface resin layer 22.

[0218] 1 to 3, the barrier substrate 1 may further include a barrier coat layer (not shown) on the (first) vapor-deposited film 40. In Fig. 1 to 3, the barrier substrate 1 may further include a barrier coat layer (not shown) on the second vapor-deposited film 42. In Fig. 1 to 3, a vapor-deposited film may be provided on only one surface of the stretched substrate.

[0219] <Gas barrier properties of barrier substrate> The oxygen permeability (unit: cc / (m 2 The oxygen permeability (day atm) is preferably less than 30, more preferably less than 20, even more preferably less than 10, still more preferably less than 5.0, particularly preferably less than 2.0, less than 0.8 or less than 0.2. The lower limit of the oxygen permeability may be, for example, 0.01. The oxygen permeability is measured in accordance with JIS K7126-2:2006 at a temperature of 23°C and a humidity of 90% RH.

[0220] The water vapor permeability (unit: g / (m 2 ·day)) is preferably less than 10, more preferably less than 8.0, even more preferably less than 5.0, even more preferably less than 3.0, particularly preferably less than 1.5, less than 0.8 or less than 0.2. The lower limit of the water vapor permeability may be, for example, 0.01. The water vapor permeability is measured in accordance with JIS K7129-2:2019 at a temperature of 40°C and a humidity of 90% RH.

[0221] [Laminate] The laminate of the first embodiment of the present disclosure comprises at least the stretched substrate or barrier substrate of the first embodiment of the present disclosure and a heat seal layer. The laminate of the second embodiment of the present disclosure comprises at least the stretched substrate or barrier substrate of the second embodiment of the present disclosure and a heat seal layer. The laminate of the third embodiment of the present disclosure comprises at least the stretched substrate or barrier substrate of the third embodiment of the present disclosure and a heat seal layer. The laminate of the fourth embodiment of the present disclosure comprises at least the stretched substrate or barrier substrate of the fourth embodiment of the present disclosure and a heat seal layer.

[0222] When describing matters common to the laminates of the first to fourth embodiments, or when there is no particular distinction between the laminates of the first to fourth embodiments, the laminates are also simply referred to as "laminates."

[0223] The laminate of the present disclosure can be suitably used as a packaging material.

[0224] <Base material> The laminate of the present disclosure includes the stretched substrate or the barrier substrate of the present disclosure. The laminate of the present disclosure may include two or more stretched substrates. The laminate of the present disclosure may include two or more barrier substrates. The details of the stretched substrate and the barrier substrate are as described above, and detailed description will be omitted in this section.

[0225] In the laminate comprising the barrier substrate and the heat seal layer, the orientation of the barrier substrate is not particularly limited. In the laminate of the second embodiment, the barrier substrate is preferably arranged so that the first vapor deposition film faces the heat seal layer side (inside of the packaging container) and the second vapor deposition film faces the opposite side to the heat seal layer (outside of the packaging container). That is, the laminate of the second embodiment preferably comprises the second vapor deposition film, the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, the first vapor deposition film, and the heat seal layer in this order. In the laminate of the fourth embodiment, the barrier substrate is preferably arranged so that the first surface resin layer faces the heat seal layer side (inside of the packaging container) and the vapor deposition film faces the opposite side to the heat seal layer (outside of the packaging container). That is, the laminate of the fourth embodiment preferably comprises the vapor deposition film, the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, and the heat seal layer in this order. In the laminate comprising the stretched substrate and the heat seal layer, the orientation of the stretched substrate is not particularly limited. In the laminates of the second and fourth aspects, the stretched substrate is preferably arranged so that the first surface resin layer faces the heat seal layer side (the inside of the packaging container) and the second surface resin layer faces the opposite side to the heat seal layer (the outside of the packaging container). That is, the laminates of the second and fourth aspects preferably comprise the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, and the heat seal layer in this order.

[0226] In one embodiment, the laminate of the present disclosure does not include an aluminum foil. Such a laminate of the present disclosure and a packaging container including the laminate have excellent recyclability.

[0227] The laminate of the present disclosure may further include a polyolefin oriented substrate containing polyolefin as a main component. Examples of polyolefin include polypropylene, polyethylene, polybutene, and polymethylpentene. Among these, polypropylene and polyethylene are preferred, and polyethylene is more preferred. Examples of the polyolefin oriented substrate include a polypropylene oriented substrate containing polypropylene as a main component, and a polyethylene oriented substrate containing polyethylene as a main component, and polyethylene is more preferred. The polyolefin oriented substrate is a polyolefin substrate that has been subjected to a stretching process. Details of the stretching process are as described above, and will not be described in this section. The polyolefin oriented substrate is, for example, a uniaxially stretched substrate or a biaxially stretched substrate.

[0228] The thickness of the oriented polyolefin substrate is preferably 5 μm or more, more preferably 8 μm or more, and even more preferably 10 μm or more, from the viewpoint of the strength and heat resistance of the laminate, and is preferably 300 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less, from the viewpoint of the processability of the laminate, for example, 5 μm or more and 300 μm or less.

[0229] The stretched polyolefin substrate may be subjected to the above-mentioned surface treatment. Such a stretched polyolefin substrate has, for example, excellent adhesion to a layer adjacent to the substrate. In addition, an anchor coat layer may be formed on the surface of the stretched polyolefin substrate using a conventionally known anchor coat agent.

[0230] A laminate further comprising an oriented polyolefin substrate may comprise, for example, an oriented polyolefin substrate, an oriented substrate or a barrier substrate of the present disclosure, and a heat seal layer, in that order, or may comprise an oriented substrate or a barrier substrate of the present disclosure, an oriented polyolefin substrate, and a heat seal layer, in that order.

[0231] <Print layer> The laminate of the present disclosure may include a printed layer on one or both sides of the substrate such as the above-mentioned stretched substrate, barrier substrate, and stretched polyolefin substrate. The laminate of the present disclosure may include a printed layer on the second heat seal layer described below.

[0232] The print layer includes an image. Examples of the image include characters, figures, patterns, symbols, and combinations thereof. The image may include text information such as a product name, the name of the item in the packaging container, the manufacturer, and the names of ingredients. The image may be a single, solid color (so-called solid image).

[0233] The printing layer can be formed, for example, by using an ink composition. Examples of methods for forming the printing layer include gravure printing, offset printing, flexographic printing, screen printing, letterpress printing, and transfer printing. From the viewpoint of reducing the environmental load, the printing layer may be formed by flexographic printing. From the viewpoint of reducing the environmental load, the printing layer may be formed by using an ink derived from biomass.

[0234] The thickness of the printed layer is preferably 0.1 μm or more, more preferably 0.2 μm or more, even more preferably 0.3 μm or more, and preferably 10 μm or less, more preferably 5 μm or less, even more preferably 3 μm or less, for example, 0.1 μm or more and 10 μm or less.

[0235] <Surface protective layer> The laminate of the present disclosure may have a surface protective layer on the printed layer provided on the second heat seal layer described later in order to improve the scratch resistance and weather resistance of the printed layer. The laminate of the present disclosure preferably has a surface protective layer that covers the entire area of ​​the printed layer. From the viewpoint of visibility of the printed layer, the surface protective layer is preferably transparent in the visible light region, and more preferably colorless and transparent.

[0236] The surface protective layer contains, for example, a thermoplastic resin, a cured product of a thermosetting resin, or a cured product of an energy ray curable compound. Among these, from the viewpoint of improving scratch resistance and weather resistance, the surface protective layer preferably contains a cured product of a thermosetting resin or a cured product of an energy ray curable compound, and more preferably contains a cured product of an energy ray curable compound. The ratio of the above cured product to the total resin components of the surface protective layer is preferably 80% by mass or more, more preferably 90% by mass or more. Examples of printing methods for the surface protective layer include letterpress printing, flexographic printing, gravure printing, offset printing, screen printing, inkjet printing, and thermal transfer printing.

[0237] The thickness of the surface protective layer is preferably 0.5 μm or more, more preferably 1 μm or more, and is preferably 15 μm or less, more preferably 10 μm or less, for example, 0.5 μm or more and 15 μm or less. A laminate having such a surface protective layer has excellent scratch resistance and weather resistance.

[0238] <Heat seal layer> The laminate of the present disclosure comprises a heat seal layer. The heat seal layer contains, as a main component, a heat-fusible resin that can be melted by heat and fused to each other. Examples of the heat-fusible resin include polyolefins such as polyethylene, polypropylene, and polymethylpentene, cyclic polyolefins, cyclic olefin copolymers, ionomer resins, acid-modified polyolefins, and terpolymers of ethylene-(meth)acrylic acid ester-unsaturated carboxylic acid. Examples of polyethylene include linear low-density polyethylene, high-pressure low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylic acid ester copolymers. Examples of acid-modified polyolefins include resins obtained by modifying polyolefins such as polyethylene and polypropylene with unsaturated carboxylic acid compounds such as (meth)acrylic acid and maleic anhydride.

[0239] In recent years, from the viewpoint of reducing the environmental load, there has been a demand for recycling packaging containers. From the viewpoint of recyclability, it is preferable that the base material and the heat seal layer are each composed of the same type of resin material (mono-materialization). In one embodiment, the heat seal layer contains polyethylene as a main component. This allows the packaging container to be mono-materialized. Such a packaging container has excellent recyclability, and for example, after collecting a used packaging container, it is not necessary to separate the base material and the heat seal layer.

[0240] In one embodiment, the content of polyethylene in the entire laminate of the present disclosure is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more. This allows, for example, the laminate to be used to produce a mono-material packaging container, improving the recyclability of the packaging container. The upper limit of the content of polyethylene is not particularly limited, but may be 99% by mass.

[0241] The heat seal layer may contain the above-mentioned additives.

[0242] The laminate of the present disclosure may include at least a first heat seal layer as the heat seal layer, a stretched substrate or a barrier substrate of the present disclosure, and a second heat seal layer as the heat seal layer, in this order. The first heat seal layer and the second heat seal layer can be melted by heating and fused to each other. Such a laminate can be suitably used, for example, as a packaging material for forming the body of a tube container body. In this case, the second heat seal layer is a sealant layer on the outer surface side of the body, and the first heat seal layer is a sealant layer on the inner surface side of the body. That is, the body includes, from the outside to the inside of the body, the second heat seal layer, the stretched substrate or the barrier substrate, and the first heat seal layer, in this order. In one embodiment, the first heat seal layer and the second heat seal layer contain polyethylene as a main component.

[0243] In the laminate, the orientation of the barrier substrate is not particularly limited. In the laminate of the second embodiment, the barrier substrate is preferably arranged so that the first vapor-deposited film faces the first heat seal layer side and the second vapor-deposited film faces the second heat seal layer side. That is, the laminate of the second embodiment preferably includes the second heat seal layer, the second vapor-deposited film, the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, the first vapor-deposited film, and the first heat seal layer in this order. In the laminate of the fourth embodiment, the barrier substrate is preferably arranged so that the first surface resin layer faces the first heat seal layer side and the vapor-deposited film faces the second heat seal layer side. That is, the laminate of the fourth embodiment preferably includes the second heat seal layer, the vapor-deposited film, the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, and the first heat seal layer in this order. In the laminate, the orientation of the stretched substrate is not particularly limited. In the laminates of the second and fourth aspects, the stretched substrate is preferably arranged so that the first surface resin layer faces the first heat seal layer and the second surface resin layer faces the second heat seal layer. That is, the laminate of the second aspect preferably includes the second heat seal layer, the second surface resin layer, the polyethylene intermediate layer, the first surface resin layer, and the first heat seal layer in this order.

[0244] The heat seal layer may have a single-layer structure or a multi-layer structure. The thickness of the heat seal layer is preferably 10 μm or more, more preferably 30 μm or more, even more preferably 50 μm or more, and particularly preferably 80 μm or more, from the viewpoint of heat sealability and recyclability of the packaging container. The thickness of the heat seal layer is preferably 300 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less, from the viewpoint of processability of the laminate. The thickness of the heat seal layer is, for example, 10 μm or more and 300 μm or less.

[0245] From the viewpoint of heat sealability, the heat seal layer is preferably an unstretched resin film, more preferably an unstretched co-extruded resin film, and each layer constituting the heat seal layer is a co-extruded resin layer. The above-mentioned resin film can be produced, for example, by using a T-die casting method or an inflation method. The concept of "unstretched film" includes not only a film that is not stretched at all, but also a film that is slightly stretched due to the tension applied during film formation.

[0246] For example, an unstretched resin film corresponding to the heat seal layer may be laminated on a stretched substrate or a barrier substrate via an adhesive layer as necessary, or a heat-fusible resin or a resin composition thereof may be melt-extruded onto a stretched substrate or a barrier substrate to form a heat seal layer. In the latter case, an adhesive layer may not be provided. Examples of the adhesive layer include the adhesive layer described below.

[0247] <Adhesive layer> The laminate of the present disclosure may include an adhesive layer between any layers, such as between the stretched substrate or the barrier substrate and the heat seal layer. Such a laminate has, for example, excellent adhesion between the stretched substrate or the barrier substrate and the heat seal layer.

[0248] The laminate of the present disclosure may, for example, comprise the stretched substrate or barrier substrate of the present disclosure, an adhesive layer, and a heat seal layer in this order, or may comprise the stretched polyolefin substrate, a second adhesive layer, the stretched substrate or barrier substrate of the present disclosure, a first adhesive layer, and a heat seal layer in this order, or may comprise the stretched substrate or barrier substrate of the present disclosure, a second adhesive layer, the stretched polyolefin substrate, a first adhesive layer, and a heat seal layer in this order. The laminate of the present disclosure may, for example, comprise the second heat seal layer, the second adhesive layer, the stretched substrate or barrier substrate of the present disclosure, a first adhesive layer, and a first heat seal layer in this order.

[0249] In one embodiment, the adhesive layer may be an adhesive layer made of an adhesive. The adhesive may be any of a one-component curing adhesive, a two-component curing adhesive, and a non-curing adhesive. The adhesive may be a solventless adhesive or a solvent-based adhesive.

[0250] Examples of solvent-free adhesives, i.e., non-solvent laminate adhesives, include polyether adhesives, polyester adhesives, silicone adhesives, epoxy adhesives, and urethane adhesives. Among these, urethane adhesives are preferred, and two-liquid curing urethane adhesives are more preferred.

[0251] Examples of solvent-based adhesives include rubber-based adhesives, vinyl-based adhesives, olefin-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and urethane-based adhesives. Among these, urethane-based adhesives are preferred, and two-liquid curing urethane-based adhesives are more preferred.

[0252] In one embodiment, the laminate of the present disclosure may be produced by laminating the stretched substrate or barrier substrate of the present disclosure, an optional stretched polyolefin substrate, and a resin film corresponding to the heat seal layer by a non-solvent lamination method using a solvent-free adhesive, or by a dry lamination method using a solvent-based adhesive.

[0253] The adhesive layer can be formed by applying an adhesive to a stretched substrate or a barrier substrate, for example, by a method such as a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a Fontaine method, or a transfer roll coating method, and then drying the adhesive.

[0254] The thickness of the adhesive layer may be 0.1 μm or more, 0.2 μm or more, 0.5 μm or more, 10 μm or less, 8 μm or less, or 6 μm or less, for example, 0.1 μm or more and 10 μm or less. The thickness of the adhesive layer may be 2 μm or less.

[0255] In one embodiment, the adhesive layer may be an adhesive resin layer containing a thermoplastic resin, or an extruded resin layer containing a thermoplastic resin. Examples of the thermoplastic resin include the above-mentioned heat-sealing resin. The thermoplastic resin may be a material derived from fossil fuels, a material derived from biomass, or both of these may be used.

[0256] The thickness of the extruded resin layer is preferably 5 μm or more, more preferably 10 μm or more, from the viewpoint of interlayer adhesion, and is preferably 30 μm or less, more preferably 25 μm or less, from the viewpoint of reducing the production cost of the laminate and improving its productivity, for example, 5 μm or more and 30 μm or less.

[0257] <Layer structure of laminate> Below, several examples of layer configurations of the laminate of the present disclosure will be given. 4A includes a barrier substrate 1, an adhesive layer 60, and a heat seal layer 80 in this order, and more specifically, a second vapor-deposited film 42, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, a first vapor-deposited film 40, an adhesive layer 60, and a heat seal layer 80 in this order. The laminate 2 may further include a printed layer (not shown), for example, on the first vapor-deposited film 40 or the second vapor-deposited film 42 of the barrier substrate 1. 4B comprises, in this order, a barrier substrate 1, an adhesive layer 60, and a heat seal layer 80, and more specifically, in this order, a vapor-deposited film 40, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, an adhesive layer 60, and a heat seal layer 80. The laminate 2 may further comprise a printed layer (not shown), and for example, may further comprise a printed layer (not shown) on the vapor-deposited film 40 or the first surface resin layer 20 of the barrier substrate 1. The laminate 2 shown in Fig. 5A includes a polyolefin oriented substrate 70, a second adhesive layer 62, a barrier substrate 1, a first adhesive layer 60, and a heat seal layer 80 in this order, specifically, a polyolefin oriented substrate 70, a second adhesive layer 62, a second vapor deposition film 42, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, a first vapor deposition film 40, a first adhesive layer 60, and a heat seal layer 80 in this order. The laminate 2 may further include a printed layer (not shown), for example, on the surface of the polyolefin oriented substrate 70 facing the barrier substrate 1. A laminate having such a configuration is suitable as a packaging material for forming a standing pouch, for example. The laminate 2 shown in Fig. 5B includes a polyolefin oriented substrate 70, a second adhesive layer 62, a barrier substrate 1, a first adhesive layer 60, and a heat seal layer 80 in this order, specifically, a polyolefin oriented substrate 70, a second adhesive layer 62, a vapor deposition film 40, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, a first adhesive layer 60, and a heat seal layer 80 in this order. The laminate 2 may further include a printed layer (not shown), for example, on the surface of the polyolefin oriented substrate 70 facing the barrier substrate 1. A laminate having such a configuration is suitable as a packaging material for forming a standing pouch, for example. The laminate 2 shown in FIG. 6A includes a second heat seal layer 82, a second adhesive layer 62, a barrier substrate 1, a first adhesive layer 60, and a first heat seal layer 80 in this order, specifically, the laminate includes a second heat seal layer 82, a second adhesive layer 62, a second vapor deposition film 42, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, a first vapor deposition film 40, a first adhesive layer 60, and a first heat seal layer 80 in this order. The laminate 2 may further include a printed layer (not shown), for example, a printed layer (not shown) on the surface of the second heat seal layer 82. A laminate having such a configuration is suitable as a packaging material for forming the body of a tube container body, for example. The laminate 2 shown in FIG. 6B includes a second heat seal layer 82, a second adhesive layer 62, a barrier substrate 1, a first adhesive layer 60, and a first heat seal layer 80 in this order, specifically, the laminate 2 includes a second heat seal layer 82, a second adhesive layer 62, a vapor deposition film 40, a second surface resin layer 22, a polyethylene intermediate layer 10, a first surface resin layer 20, a first adhesive layer 60, and a first heat seal layer 80 in this order. The laminate 2 may further include a printed layer (not shown), for example, a printed layer (not shown) on the surface of the second heat seal layer 82. A laminate having such a configuration is suitable as a packaging material for forming the body of a tube container body, for example. 4 to 6, the barrier substrate 1 may further include a barrier coat layer (not shown) on the (first) vapor-deposited film 40. In FIG. 4 to 6, the barrier substrate 1 may further include a barrier coat layer (not shown) on the second vapor-deposited film 42. In FIG. 4 to 6, the orientation of the barrier substrate 1 may be reversed. In FIG. 4 to 6, the laminate 2 may include a stretched substrate instead of the barrier substrate 1, or may include a barrier substrate having a vapor-deposited film on only one surface of the stretched substrate.

[0258] [Packaging container] The laminate of the present disclosure can be suitably used for packaging material applications. The packaging material is used to produce a packaging container. By using at least the laminate of the present disclosure, a packaging container having excellent gas barrier properties can be produced.

[0259] Examples of the packaging container include a packaging bag, a tube container, and a container with a lid.

[0260] Examples of packaging bags include packaging bags of various shapes, such as a standing pouch type, a side seal type, a two-sided seal type, a three-sided seal type, a four-sided seal type, an envelope seal type, a grooving seal type (pillow seal type), a pleated seal type, a flat bottom seal type, a square bottom seal type, and a gusset type. The packaging bag may be, for example, a small bag or a zipper bag. The packaging bag may be a refill pouch, particularly a standing pouch, that contains contents such as liquids and powders and is refilled into a container such as a bottle. The packaging bag may be, for example, a soft packaging bag.

[0261] The packaging bag of the present disclosure comprises the laminate of the present disclosure. The packaging bag of the present disclosure is, for example, one or more laminates of the present disclosure; a seal portion where the heat seal layers of the laminate are joined together; A storage section for storing contents; has. The seal portion includes an inner edge that defines the receiving portion.

[0262] Examples of methods for forming the sealed portion include heat sealing, which involves melting the heat seal layers of the laminate by heating or the like to fuse the heat seal layers together, and specifically include bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, and ultrasonic sealing. For example, after the contents are placed in the packaging bag, the opening of the packaging bag is heat sealed to seal the packaging bag.

[0263] The packaging bag may have an easy-to-open portion. Examples of the easy-to-open portion include a notch portion that serves as a starting point for tearing the packaging bag, and a half-cut line formed by laser processing or a cutter as a path for tearing the packaging bag.

[0264] In one embodiment, the laminate of the present disclosure is used as a lid material in a lidded container. The lidded container comprises a container body having a storage section, and a lid material joined (heat sealed) to the container body so as to seal the storage section. Here, the lid material, i.e., the heat seal layer of the laminate, and the container body are heat sealed. Examples of the shape of the container body include a cup shape and a cylindrical shape with a bottom. The container body is made of, for example, polystyrene, polypropylene, polyethylene, or paper.

[0265] The contents contained in the packaging container include, for example, liquids, solids, powders, and gels. The contents may be food or beverages, or non-food or beverages such as chemicals, cosmetics, medicines, metal parts, and electronic parts. The contents include, for example, shampoo, rinse, conditioner, hand soap, body soap, air freshener, deodorant, insect repellent, fabric softener, detergent; sauce, soy sauce, dressing, edible oil, mayonnaise, ketchup, syrup, cooking alcohol, other liquid or viscous seasonings; fruit juice; spices; liquid beverages, jelly beverages, liquid soups, powdered soups, instant foods, other food and beverages; cream; toothpaste; metal parts, and electronic parts. For example, toothpaste is a preferred content of a tube container.

[0266] In one embodiment, a packaging bag can be produced by folding the laminate of the present disclosure in half and overlapping it so that the stretched substrate or barrier substrate is on the outside and the heat seal layer is on the inside, and then heat sealing the ends, etc. In another embodiment, a packaging bag can be produced by overlapping a plurality of laminates of the present disclosure so that the heat seal layers face each other, and then heat sealing the ends, etc. The entire packaging bag may be made of the above-mentioned laminate, or only a part of the packaging bag may be made of the above-mentioned laminate.

[0267] In one embodiment, the standing pouch includes a body portion composed of a side sheet and a bottom portion composed of a bottom sheet. The bottom sheet retains the shape of the side sheet, thereby imparting self-supporting properties to the pouch, and the pouch can be made into a standing type pouch. A storage portion for storing contents is formed within the area surrounded by the side sheet and the bottom sheet. In the standing pouch, only the side sheet may be the laminate of the present disclosure, only the bottom sheet may be the laminate of the present disclosure, or both the side sheet and the bottom sheet may be the laminate of the present disclosure.

[0268] In one embodiment, the side sheet can be formed by making a bag so that the heat seal layer of the laminate of the present disclosure is the innermost layer. In one embodiment, the side sheet can be formed by preparing two laminates of the present disclosure, overlapping them so that the heat seal layers face each other, and heat sealing the side edges on both sides to make a bag.

[0269] In another embodiment, the side sheet can be formed by preparing two laminates of the present disclosure, overlapping them with the heat seal layers facing each other, inserting two laminates folded in a V shape with the heat seal layers facing outward between the laminates at the side edges on both sides of the overlapped laminates, and heat sealing them. According to this production method, a standing pouch having a body with side gussets can be obtained.

[0270] In one embodiment, the bottom sheet can be formed by inserting the laminate of the present disclosure between the lower parts of the side sheets that have been made into a bag, and heat sealing the laminate. More specifically, the bottom sheet can be formed by inserting the laminate folded in a V-shape with the heat seal layer on the outside between the lower parts of the side sheets that have been made into a bag, and heat sealing the laminate.

[0271] In one embodiment, two laminates of the present disclosure are prepared, and these are stacked so that the heat seal layers face each other, and then another laminate of the present disclosure is folded in a V shape so that the heat seal layer faces outward, and this is sandwiched under the lower part of the laminates that face each other, and heat sealed to form a bottom. Next, two sides adjacent to the bottom are heat sealed to form a body. In this way, a standing pouch of one embodiment can be formed.

[0272] [Tube container body] The tube container body of the present disclosure comprises the laminate of the present disclosure. The tube container body of the present disclosure will be described below with reference to the drawings. Fig. 7 is a diagram showing a simplified configuration of a tube container 120, and Fig. 8 is a cross-sectional view taken along line AA in Fig. 7. As shown in Fig. 7, the tube container body 121 includes a head 122 and a body 123, and the body 123 is made of the laminate of the present disclosure.

[0273] <Head> The head 122 includes a shoulder 124 connected to one end of the body 123, and a spout 125 connected to the shoulder 124. In one embodiment, the spout 125 includes threads 127 for threading a cap 126 thereon.

[0274] In one embodiment, the head is formed of a resin composition containing a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene, polyesters, cellulose resins, and vinyl resins. The resin composition may contain the additives.

[0275] The head portion can be manufactured by a conventional method, for example, by compression molding or injection molding, and can be joined to the body portion.

[0276] <Torso> In the tube container body 121 of the present disclosure, the body 123 is connected to a shoulder 124 of the head 122. The body 123 includes a fused portion 128 formed, for example, by overlapping the laminate of the present disclosure at one end so that the surface on the first heat seal layer side of the laminate at the other end is in contact with the surface on the second heat seal layer side of the laminate at the other end, rolling the laminate into a cylindrical shape, and heat sealing the overlapped portion. The body 123 includes a bottom seal portion 129 formed, for example, by heat sealing the opening of the laminate rolled into a cylindrical shape.

[0277] Examples of the heat sealing method include conventionally known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, ultrasonic sealing and flame sealing.

[0278] For example, the laminate of the present disclosure may be rolled into a cylindrical shape by overlapping the first heat seal layer side surface of one end of the laminate with the second heat seal layer side surface of the other end, and heat sealing the overlapped portion to produce a cylindrical body. From the viewpoint of heat sealability, it is preferable that one overlapped end is the first heat seal layer and the other end is the second heat seal layer. In this case, the first heat seal layer and the second heat seal layer are melted and joined to form a fused portion.

[0279] Therefore, it is preferable that the second heat seal layer does not have a printed layer or a surface protective layer formed in an area to be heat sealed when forming the body of the tube container body, so that the area can be well heat sealed when forming the cylindrical body using the laminate of the present disclosure.

[0280] In the above embodiment, the fusion portion is formed by overlapping, but the same surfaces of both ends of the laminate may be butted together and the first heat seal layers may be heat sealed to be joined. In this case, a printed layer and a surface protective layer may be formed on the second heat seal layer at both ends of the laminate. Also, in this case, a joining tape may be attached to the outer surface side of the body so as to cover the joining portion. It is preferable that the printed layer and the surface protective layer are not provided at the portion of the laminate where the joining tape is attached. The joining tape may be provided on both the inner surface and the outer surface of the body.

[0281] [Tube container] The tube container of the present disclosure will be described below with reference to the drawings. As shown in FIG. 7, the tube container 120 of the present disclosure includes a tube container body 121 and a cap 26 attached to a head portion 122.

[0282] <Tube container body> The tube container body has been described above, so a description thereof will be omitted here.

[0283] <Cap> The cap is detachably attached to the extraction port of the head, and serves to close the extraction port. In one embodiment, the cap is formed of a resin composition containing a thermoplastic resin. Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene, polyesters, cellulose resins, and vinyl resins. The resin composition may contain the additives.

[0284] The cap may be a screw type having a groove on the inner surface of the cap so as to screw into the threads 127 of the extraction port 125, as shown in FIG. 7, or it may be a plug type that fits into the extraction port 125 by plugging it.

[0285] [Aspects of the present disclosure] The present disclosure relates to, for example, the following [1] to

[29] . [1] A laminated ... 3 Super 0.960g / cm 3 Stretched substrate having a density of: [2] The stretched substrate according to [1], wherein the gas barrier resin in the first surface resin layer and the second surface resin layer each independently comprises at least one selected from an ethylene-vinyl alcohol copolymer and a polyamide. [3] The stretched substrate according to [1] or [2], wherein the gas barrier resin in the first surface resin layer contains an aromatic polyamide, and the gas barrier resin in the second surface resin layer contains an aromatic polyamide. [4] The stretched substrate according to any one of [1] to [3], further comprising a first adhesive resin layer between the first surface resin layer and the polyethylene intermediate layer, and further comprising a second adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. [5] A laminated laminated laminated laminate comprising at least a first surface resin layer containing polyethylene and an adhesive resin, one or more polyethylene intermediate layers containing polyethylene as a main component, and a second surface resin layer containing a gas barrier resin as a main component, in this order, wherein the polyethylene in at least one layer selected from the first surface resin layer and the polyethylene intermediate layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or has a viscosity of 0.930 g / cm 3 Super 0.960g / cm 3 Stretched substrate having a density of: [6] The stretched substrate according to [5], wherein the gas barrier resin in the second surface resin layer contains an aromatic polyamide. [7] The stretched substrate according to [5] or [6], wherein the content of the polyethylene in the first surface resin layer is 60% by mass or more and 95% by mass or less, and the content of the adhesive resin is 5% by mass or more and 40% by mass or less. [8] The stretched substrate according to any one of [5] to [7], further comprising an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer. [9] A laminated laminated laminated laminate comprising at least a first surface resin layer containing polyethylene and an adhesive resin, one or more layers of a polyethylene intermediate layer containing polyethylene as a main component, and a second surface resin layer containing polyethylene and an adhesive resin, in this order, wherein the polyethylene in at least one layer selected from the first surface resin layer, the polyethylene intermediate layer, and the second surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or has an elastic modulus of 0.930 g / cm 3 Super 0.960g / cm 3 Stretched substrate having a density of:

[10] The stretched substrate according to [9], wherein the first surface resin layer and the second surface resin layer each independently have a polyethylene content of 60% by mass or more and 95% by mass or less, and a adhesive resin content of 5% by mass or more and 40% by mass or less.

[11] A laminated laminated laminate comprising at least a first surface resin layer containing polyethylene as a main component, one or more polyethylene intermediate layers containing polyethylene as a main component, and a second surface resin layer containing a gas barrier resin as a main component or containing polyethylene and an adhesive resin, in this order, wherein the polyethylene in at least one layer selected from the first surface resin layer, the polyethylene intermediate layer, and the second surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or has a viscosity of 0.930 g / cm 3 Super 0.960g / cm 3 Stretched substrate having a density of:

[12] The stretched substrate according to

[11] , wherein the gas barrier resin in the second surface resin layer contains at least one selected from an ethylene-vinyl alcohol copolymer and a polyamide.

[13] The stretched substrate according to

[11] or

[12] , wherein the gas barrier resin in the second surface resin layer contains an aromatic polyamide.

[14] The stretched substrate according to any one of

[11] to

[13] , wherein in the second surface resin layer, the content of the polyethylene is 60% by mass or more and 95% by mass or less, and the content of the adhesive resin is 5% by mass or more and 40% by mass or less.

[15] The stretched substrate according to any one of

[11] to

[14] , wherein the second surface resin layer contains the gas barrier resin as a main component, and the stretched substrate further comprises an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer.

[16] The stretched substrate according to any one of the above [1] to

[15] , which is a stretched film of a coextruded resin film.

[17] The stretched substrate according to any one of the above [1] to

[16] , wherein the stretched substrate is a biaxially stretched substrate.

[18] The stretched substrate according to any one of the above [1] to

[17] , wherein at least one of the polyethylene intermediate layers contains at least one type of polyethylene selected from high density polyethylene and medium density polyethylene, and a linear low density polyethylene.

[19] The stretched substrate according to

[18] , wherein the total content of high-density polyethylene and medium-density polyethylene in at least one of the polyethylene intermediate layers is 20% by mass or more and 60% by mass or less, and the content of linear low-density polyethylene is 40% by mass or more and 80% by mass or less.

[20] The high density polyethylene has a viscosity of 0.945 g / cm 3 Super 0.960g / cm 3 and the linear low density polyethylene is an ethylene-α-olefin copolymer having a density of 0.930 g / cm or less, 3The stretched substrate according to

[18] or

[19] , which is an ethylene-α-olefin copolymer having a density below.

[21] A barrier substrate comprising: a stretched substrate according to any one of [1] to

[10] and

[16] to

[20] above; and a vapor-deposited film provided on a surface of at least one layer selected from the first surface resin layer and the second surface resin layer of the stretched substrate; or a stretched substrate according to any one of

[11] to

[20] above; and a vapor-deposited film provided on a surface of the second surface resin layer of the stretched substrate.

[22] A barrier substrate comprising at least a first vapor-deposited film, the stretched substrate according to any one of [1] to

[20] above, and a second vapor-deposited film, in this order, wherein the first vapor-deposited film is provided on a surface of the first surface resin layer, and the second vapor-deposited film is provided on a surface of the second surface resin layer.

[23] A laminate comprising at least the barrier substrate according to

[21] or

[22] above and a heat seal layer.

[24] The laminate according to

[23] , wherein the heat seal layer contains polyethylene as a main component, and the content of polyethylene in the entire laminate is 80 mass% or more.

[25] The laminate according to

[23] or

[24] , comprising at least a first heat seal layer, the barrier substrate, and a second heat seal layer, in this order.

[26] A packaging container comprising the laminate described in any one of

[23] to

[25] above.

[27] The packaging container described in

[26] above, which is a packaging bag.

[28] A tube container body having a head and a body, the head having a shoulder portion connected to one end of the body and an extraction port portion connected to the shoulder portion, and the body being constructed from the laminate described in

[25] .

[29] A tube container comprising the tube container body described in

[28] above and a cap. EXAMPLES

[0286] The stretched substrate and the barrier substrate of the present disclosure will be described in more detail below with reference to examples, but the stretched substrate and the barrier substrate of the present disclosure are not limited to the following examples. In the following description, "parts by mass" will be simply referred to as "parts".

[0287] [Material for stretched substrate] The following materials were used in making the stretched substrate: Ethylene-vinyl alcohol copolymer (EVOH) Kuraray, EVAL G156B, Melting point: 157°C, MFR: 6.4g / 10min, ethylene content: 48mol% Aliphatic polyamide (aliphatic PA) Made by UBE, Polyamide 6 (PA6) 1020, Melting point: 220℃, Relative viscosity: 3.04 Aromatic polyamide (aromatic PA) Mitsubishi Gas Chemical Company, MX nylon (MXD6) S6007, Polymetaxylylene adipamide, Melting point: 240℃, relative viscosity: 2.7 Adhesive resin (acid-modified LLDPE) Mitsui Chemicals, Admer NF587, Maleic anhydride graft modified linear low density polyethylene, Density: 0.910g / cm 3 Melting point: 120℃, MFR: 2.3g / 10min High density polyethylene (HDPE) Metallocene HDPE, ethylene-1-octene copolymer, Density: 0.955g / cm 3 Melting point: 130℃, MFR: 1.5g / 10min · Linear low density polyethylene (LLDPE) Dow Chemical's INNATE TF80 Metallocene LLDPE, ethylene-1-octene copolymer, Density: 0.926g / cm 3 , MFR: 1.7g / 10min · Acid-modified linear low-density polyethylene (MAH-LLDPE) Arkema, OREVAC 18302N, Maleic anhydride graft modified linear low density polyethylene, Density: 0.912g / cm 3 Melting point: 123℃, MFR: 1.5g / 10min Compatibilizer Dow Chemical, RETAIN 3000, Maleic anhydride grafted polyethylene, density: 0.870g / cm 3 ·Anti-blocking agents (AB agents) Silica particles, average particle size: 3.5 μm

[0288] [Preparation of Composition] A blended polyethylene (A) was prepared by mixing 40 parts of HDPE and 60 parts of LLDPE (INNATE TF80). A blended polyethylene (B1) was prepared by mixing 90 parts of LLDPE (INNATE TF80) and 10 parts of acid-modified LLDPE (OREVAC 18302N). A blended polyethylene (B2) was prepared by mixing 18 parts of HDPE, 72 parts of LLDPE (INNATE TF80), and 10 parts of acid-modified LLDPE (OREVAC 18302N). A blended polyethylene (C) was prepared by mixing 40 parts of HDPE, 60 parts of LLDPE (INNATE TF80), and 0.2 parts (2,000 ppm) of an AB agent. A blended polyethylene (D) was prepared by mixing 20 parts of HDPE, 80 parts of LLDPE (INNATE TF80), and 0.2 parts (2,000 ppm) of an AB agent. A blend polyamide (A) was prepared by mixing 50 parts of an aromatic polyamide (MXD6) and 50 parts of an aliphatic polyamide (Polyamide 6 1020).

[0289] [Example 1A] Ethylene-vinyl alcohol copolymer (G156B); Adhesive resin (NF587) and A blended polyethylene (A); Adhesive resin (NF587) and Ethylene-vinyl alcohol copolymer (G156B); The five-layer film was obtained by co-extrusion using a T-die casting method. The film was stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD), and a sequential biaxial stretching process was performed to produce a stretched substrate (biaxially stretched film) with a thickness of 25 μm. In Example 1A, biaxial stretching was performed well.

[0290] The stretched substrate thus obtained is A second surface resin layer (EVOH layer) having a thickness of 1 μm; a second adhesive resin layer having a thickness of 2 μm; A blended polyethylene (A) layer having a thickness of 19 μm; A first adhesive resin layer having a thickness of 2 μm; A first surface resin layer (EVOH layer) having a thickness of 1 μm; are provided in this order.

[0291] An aluminum (AL) film having a thickness of 30 nm was formed by vapor deposition on each of the first and second surface resin layers of the stretched substrate by PVD, thus obtaining a barrier substrate. A 30 nm thick alumina vapor deposition film was formed on each of the first and second surface resin layers of the stretched substrate by the PVD method. 47.69 g of water, 22.8 g of isopropyl alcohol, and 1.13 g of 0.5N hydrochloric acid were mixed to obtain a solution. 27.04 g of tetraethoxysilane as a metal alkoxide and 1.35 g of 3-glycidoxypropyltriethoxysilane as a silane coupling agent were mixed with this solution while cooling to 10°C to obtain solution A. 4.14 g of polyvinyl alcohol with a saponification degree of 99% or more and a polymerization degree of 2,400 as a water-soluble polymer, 91.07 g of water, and 4.79 g of isopropyl alcohol were mixed to obtain solution B. Solution A and solution B were mixed so that the ratio of solution A / solution B was 65.5 / 34.5 by mass to obtain a barrier coating agent. The surface of the alumina deposition film was coated with the above-mentioned barrier coating agent by spin coating, and then heat-treated in an oven at 100° C. for 8 seconds to form a barrier coating layer with a thickness of 0.3 μm. In this way, a barrier substrate was obtained. A 30 nm thick silica vapor deposition film was formed on each of the first and second surface resin layers of the stretched substrate instead of the alumina vapor deposition film, and the above barrier coat layer was further formed on the silica vapor deposition film to obtain a barrier substrate.

[0292] [Examples 2A to 4A] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1A, except that an aliphatic polyamide (polyamide 6 1020), an aromatic polyamide (MXD6) or a blended polyamide (A) was used instead of the ethylene-vinyl alcohol copolymer (G156B). In Examples 2A to 4A, biaxial stretching was successfully performed.

[0293] [Example 1B] Ethylene-vinyl alcohol copolymer (G156B); Adhesive resin (NF587) and A blended polyethylene (A); A blended polyethylene (A); A blended polyethylene (B); The five-layer film was obtained by co-extrusion using a T-die casting method. The film was stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD), and a sequential biaxial stretching process was performed to produce a stretched substrate (biaxially stretched film) with a thickness of 25 μm. In Example 1B, biaxial stretching was performed well.

[0294] The stretched substrate thus obtained is A second surface resin layer (EVOH layer) having a thickness of 1 μm; An adhesive resin layer having a thickness of 2 μm; A second polyethylene layer (blend polyethylene (A) layer) having a thickness of 19 μm; A first polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A first surface resin layer (a blended polyethylene (B1) layer) having a thickness of 1 μm; are provided in this order. Using the above stretched substrate, three types of barrier substrates were produced in the same manner as in Example 1A.

[0295] [Examples 2B to 4B] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1B, except that an aliphatic polyamide (polyamide 6 1020), an aromatic polyamide (MXD6) or a blended polyamide (A) was used instead of the ethylene-vinyl alcohol copolymer (G156B). In Examples 2B to 4B, biaxial stretching was successfully performed.

[0296] [Example 1C] Blended polyethylene (B1); A blended polyethylene (A); A blended polyethylene (A); A blended polyethylene (A); Blended polyethylene (B1); The five-layer film was obtained by co-extrusion using a T-die casting method. The film was stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD), and a sequential biaxial stretching process was performed to produce a stretched substrate (biaxially stretched film) with a thickness of 25 μm. In Example 1C, biaxial stretching was performed well.

[0297] The stretched substrate thus obtained is A second surface resin layer (blend polyethylene (B1) layer) having a thickness of 1 μm; a third polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A second polyethylene layer (blend polyethylene (A) layer) having a thickness of 19 μm; A first polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A first surface resin layer (a blended polyethylene (B1) layer) having a thickness of 1 μm; are provided in this order. Using the above stretched substrate, three types of barrier substrates were produced in the same manner as in Example 1A.

[0298] [Example 1D] Ethylene-vinyl alcohol copolymer (G156B); Adhesive resin (NF587) and A blended polyethylene (A); A blended polyethylene (A); A blended polyethylene (C); The five-layer film was obtained by co-extrusion using a T-die casting method. The film was then stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD) to produce a 25 μm-thick stretched substrate (biaxially stretched film). In Example 1D, biaxial stretching was performed well.

[0299] The stretched substrate thus obtained is A second surface resin layer (EVOH layer) having a thickness of 1 μm; An adhesive resin layer having a thickness of 2 μm; A second polyethylene layer (blend polyethylene (A) layer) having a thickness of 19 μm; A first polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A first surface resin layer (a blended polyethylene (C) layer) having a thickness of 1 μm; are provided in this order.

[0300] Three types of barrier substrates were prepared as follows. An aluminum (AL) film having a thickness of 30 nm was formed by vapor deposition on the surface of the second surface resin layer of the stretched substrate by the PVD method, thus obtaining a barrier substrate. A 30 nm thick alumina vapor deposition film was formed on the surface of the second surface resin layer of the stretched substrate by PVD. The above barrier coating agent was coated on the surface of the alumina vapor deposition film by spin coating, and the resultant was heated in an oven at 100°C for 8 seconds to form a 0.3 μm thick barrier coating layer. In this way, a barrier substrate was obtained. A 30 nm thick silica vapor deposition film was formed on the surface of the second surface resin layer of the stretched substrate instead of the alumina vapor deposition film, and the above barrier coat layer was further formed on the silica vapor deposition film to obtain a barrier substrate.

[0301] [Examples 2D to 4D] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1D, except that an aliphatic polyamide (polyamide 6 1020), an aromatic polyamide (MXD6) or a blended polyamide (A) was used instead of the ethylene-vinyl alcohol copolymer (G156B). In Examples 2D to 4D, biaxial stretching was successfully performed.

[0302] [Example 1E] Blended polyethylene (B1); A blended polyethylene (A); A blended polyethylene (A); A blended polyethylene (A); A blended polyethylene (D); The five-layer film was obtained by co-extrusion using a T-die casting method. The film was then stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD) to produce a 25 μm-thick stretched substrate (biaxially stretched film). In Example 1E, biaxial stretching was performed well.

[0303] The stretched substrate thus obtained is A second surface resin layer (blend polyethylene (B1) layer) having a thickness of 1 μm; a third polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A second polyethylene layer (blend polyethylene (A) layer) having a thickness of 19 μm; A first polyethylene layer (a blended polyethylene (A) layer) having a thickness of 2 μm; A first surface resin layer (a blended polyethylene (D) layer) having a thickness of 1 μm; are provided in this order. Using the above stretched substrate, three types of barrier substrates were produced in the same manner as in Example 1D.

[0304] [Example 2E] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1E, except that the blending composition of polyethylene and the like in each layer was changed as shown in Table 5. In Example 2E, biaxial stretching was successfully performed. In Table 5, the blending amount of the AB agent in the first surface resin layer was 2,000 ppm.

[0305] [Comparative Example 1] A monolayer film was obtained by extruding LLDPE (INNATE TF80) by a T-die casting method. The film was stretched 5 times in the machine direction (MD) and then 8.5 times in the width direction (TD) to produce a stretched substrate (biaxially stretched film) with a thickness of 25 μm. Three types of barrier substrates were produced using the above stretched substrate in the same manner as in Example 1A. Three types of barrier substrates were produced using the above stretched substrate in the same manner as in Example 1D.

[0306] [Gas barrier property evaluation] The oxygen permeability (cc / (m) of each stretched substrate and each barrier substrate (hereinafter also referred to as "test piece") obtained in the examples and comparative examples was 2 ·day·atm)) and water vapor permeability (g / (m 2 The evaluation results are shown in each table.

[0307] <Oxygen permeability> The oxygen permeability of the test piece was measured in an environment of temperature 23° C. and humidity 90% RH in accordance with JIS K7126-2:2006 using an oxygen permeability measuring device (OX-TRAN2 / 20 manufactured by MOCON). A: Oxygen permeability is less than 0.2. B: Oxygen permeability is 0.2 or more and less than 0.8. C: Oxygen permeability is 0.8 or more and less than 2.0. D: Oxygen permeability is 2.0 or more and less than 10. E: Oxygen permeability is 10 or more and less than 30. F: Oxygen permeability is 30 or more and less than 100. G: Oxygen permeability is 100 or more.

[0308] <Water vapor permeability> The water vapor permeability of the test pieces was measured in an environment of temperature 40°C and humidity 90% RH in accordance with JIS K7129-2:2019 using a water vapor permeability measuring device (PERMATRAN-w 3 / 33 manufactured by MOCON). A: The water vapor transmission rate is less than 0.2. B: The water vapor permeability is 0.2 or more and less than 0.8. C: Water vapor permeability is 0.8 or more and less than 1.5. D: Water vapor permeability is 1.5 or more and less than 3.0. E: Water vapor permeability is 3.0 or more and less than 5.0. F: Water vapor permeability is 5.0 or more and less than 10. G: Water vapor permeability is 10 or more and less than 100.

[0309] [T-shaped peel test] A 20 μm-thick general OPP film, one side of which had been corona-treated, was applied in an amount of 3 g / m to the vapor-deposited film surface or the barrier coat layer surface of each of the barrier substrates obtained in the Examples and Comparative Examples. 2 The layers were bonded together using a urethane adhesive (RU77T / H7, manufactured by Rock Paint Co., Ltd.) to prepare test pieces with a width of 15 mm. In accordance with JIS K6854-3:1999 (Adhesives - Test method for peel adhesion strength - Part 3: T-peel), a T-peel test was carried out using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) at a test speed of 50 mm / min and a temperature of 23°C, and the peel strength (N / 15 mm) of the vapor-deposited film against each layer was measured. The results are shown in the tables.

[0310] [Heat resistance evaluation 1: Print resistance evaluation] The surface of the stretched substrate prepared above was subjected to a corona discharge treatment. An image was formed on the corona discharge treated surface of the stretched substrate by gravure printing using an oil-based gravure ink (manufactured by DIC Graphics Corporation, trade name: Finart). The heat resistance was evaluated according to the following criteria. A: No significant shrinkage of the stretched substrate occurred when the print dried. B: Significant shrinkage of the stretched substrate occurred when the print dried.

[0311] [Heat resistance evaluation 2: 170℃ heat seal resistance evaluation] The surface of the stretched substrate prepared above was subjected to a corona discharge treatment. An image was formed on the corona discharge treated surface of the stretched substrate by gravure printing using an oil-based gravure ink (manufactured by DIC Graphics Corporation, product name: Finart) to obtain a printed film. The printed film was bonded to a 40 μm-thick LLDPE film obtained by forming Evolue SP2020 (manufactured by Mitsui Chemicals) as a single layer film using a urethane-based dry lamination adhesive. The LLDPE film surfaces of the laminated films were placed face to face, and one side was sandwiched between an aluminum seal bar set to 170°C and heat sealed (1kgf / cm 2 The heat-sealed portion was then subjected to a pressure of 100 MPa for 1 second, and the thermal shrinkage state of the laminate film in the heat-sealed portion was observed. The heat resistance was evaluated according to the following criteria. A: No film shrinkage occurred when heat sealed at 170°C. B: Almost no film shrinkage occurred when heat sealed at 170°C. C: The film significantly shrunk when heat sealed at 170°C.

[0312] [Table 1]

[0313] [Table 2]

[0314] [Table 3]

[0315] [Table 4]

[0316] [Table 5]

[0317] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1A, except that the polyethylene intermediate layer contained about 23% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in this example were comparable to those in Example 1A. Stretched substrates and barrier substrates were prepared in the same manner as in Examples 2A to 4A, except that the polyethylene intermediate layer contained about 11.5% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in these examples were comparable to those of the examples with the corresponding layer configurations (Examples 2A to 4A).

[0318] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1B, except that the second polyethylene layer contained about 12% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in this example were comparable to those in Example 1B. Stretched substrates and barrier substrates were prepared in the same manner as in Examples 2B to 4B, except that the second polyethylene layer contained about 4% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in these examples were comparable to those of the examples with the corresponding layer configurations (Examples 2B to 4B).

[0319] A stretched substrate and a barrier substrate were prepared in the same manner as in Example 1D, except that the second polyethylene layer contained about 12% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in this example were comparable to those in Example 1D. Stretched substrates and barrier substrates were prepared in the same manner as in Examples 2D to 4D, except that the second polyethylene layer contained about 4% by mass of a compatibilizer (RETAIN 3000). The results of each evaluation in these examples were comparable to those of the examples with the corresponding layer configurations (Examples 2D to 4D).

[0320] Except for using the blended polyethylene (B2) instead of the blended polyethylene (B1), stretched substrates and barrier substrates were prepared in the same manner as in Examples 1B to 4B and Example 1C. The results of each evaluation in these Examples were comparable to those of the Examples (Examples 1B to 4B and Example 1C) with the corresponding layer configurations.

[0321] [Examples 1A' to 4A'] The stretched substrates and barrier substrates of Examples 1A' to 4A' were produced in the same manner as in Examples 1A to 4A, except that the thickness of the first adhesive resin layer was changed to 1.5 μm, the thickness of the polyethylene intermediate layer was changed to 13 μm, the thickness of the second adhesive resin layer was changed to 1.5 μm, and the thickness of the stretched substrate was changed to 18 μm. In Examples 1A' to 4A', biaxial stretching was successfully performed. The results of each evaluation in Examples 1A' to 4A' were comparable to the results of the examples (Examples 1A to 4A) with the corresponding example numbers.

[0322] [Examples 1B' to 4B'] The stretched substrates and barrier substrates of Examples 1B' to 4B' were produced in the same manner as in Examples 1B to 4B, except that the thickness of the first polyethylene layer was changed to 1.5 μm, the thickness of the second polyethylene layer was changed to 13 μm, the thickness of the adhesive resin layer was changed to 1.5 μm, and the thickness of the stretched substrate was changed to 18 μm. In Examples 1B' to 4B', biaxial stretching was successfully performed. The results of each evaluation in Examples 1B' to 4B' were comparable to the results of the examples (Examples 1B to 4B) with the corresponding example numbers.

[0323] [Example 1C'] The stretched substrate and barrier substrate of Example 1C' were produced in the same manner as in Example 1C, except that the thickness of the first polyethylene layer was changed to 1.5 μm, the thickness of the second polyethylene layer was changed to 13 μm, the thickness of the third polyethylene layer was changed to 1.5 μm, and the thickness of the stretched substrate was changed to 18 μm. In Example 1C', biaxial stretching was successfully performed. The results of each evaluation in Example 1C' were comparable to those in Example 1C.

[0324] [Examples 1D' to 4D'] The stretched substrates and barrier substrates of Examples 1D' to 4D' were produced in the same manner as in Examples 1D to 4D, except that the thickness of the first polyethylene layer was changed to 1.5 μm, the thickness of the second polyethylene layer was changed to 13 μm, the thickness of the adhesive resin layer was changed to 1.5 μm, and the thickness of the stretched substrate was changed to 18 μm. In Examples 1D' to 4D', biaxial stretching was successfully performed. The results of each evaluation in Examples 1D' to 4D' were comparable to the results of the examples (Examples 1D to 4D) with the corresponding example numbers.

[0325] [Examples 1E' to 2E'] The stretched substrates and barrier substrates of Examples 1E' to 2E' were produced in the same manner as in Examples 1E to 2E, except that the thicknesses of the first polyethylene layer, second polyethylene layer, and third polyethylene layer were changed to 1.5 μm, 13 μm, and 1.5 μm, respectively, and the thickness of the stretched substrate was changed to 18 μm. In Examples 1E' to 2E', biaxial stretching was successfully performed. The results of each evaluation in Examples 1E' to 2E' were comparable to the results of the examples (Examples 1E to 2E) with the corresponding Example numbers.

[0326] [Comparative Example 1'] Except for changing the thickness of the stretched substrate to 18 μm, a stretched substrate and a barrier substrate of Comparative Example 1′ were produced in the same manner as in Comparative Example 1. The results of each evaluation in Comparative Example 1′ were comparable to those in Comparative Example 1. [Explanation of symbols]

[0327] 1. Barrier substrate 2. Laminate 10 Polyethylene layer 11 First polyethylene layer 12 Second polyethylene layer 13 Third polyethylene layer 20 First surface resin layer 22 Second surface resin layer 30 (First) adhesive resin layer 32 Second adhesive resin layer 40 (First) Evaporation Film 42 Second deposition film 60 Adhesive layer, first adhesive layer 62 Second adhesive layer 70 Polyolefin oriented substrate 80 Heat seal layer, first heat seal layer 82 Second heat seal layer 120 Tube container 121 Tube container body 122 Head 123 Torso 124 Shoulder 125 Extraction port 126 Cap 127 Spiral 128 Fusion part 129 Bottom seal

Claims

1. a first surface resin layer containing a gas barrier resin as a main component; one or more polyethylene intermediate layers containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component; In this order, The polyethylene in at least one of the polyethylene intermediate layers comprises at least one polyethylene selected from high density polyethylene and medium density polyethylene, or 3 Super 0.960g / cm 3 having a density of Stretched base material.

2. The stretched substrate according to claim 1, wherein the gas barrier resin in the first surface resin layer and the gas barrier resin in the second surface resin layer each independently contain at least one selected from an ethylene-vinyl alcohol copolymer and a polyamide.

3. the gas barrier resin in the first surface resin layer contains an aromatic polyamide, the gas barrier resin in the second surface resin layer contains an aromatic polyamide; The stretched substrate of claim 1.

4. 2. The stretched substrate according to claim 1, further comprising a first adhesive resin layer between the first surface resin layer and the polyethylene intermediate layer, and a second adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer.

5. a first surface resin layer containing polyethylene and an adhesive resin; one or more polyethylene intermediate layers containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component; In this order, The polyethylene in at least one layer selected from the first surface resin layer and the polyethylene intermediate layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or 3 Super 0.960g / cm 3 having a density of Stretched base material.

6. The stretched substrate according to claim 5 , wherein the gas barrier resin in the second surface resin layer contains an aromatic polyamide.

7. The stretched substrate according to claim 5 , wherein the content of the polyethylene in the first surface resin layer is from 60% by mass to 95% by mass, and the content of the adhesive resin is from 5% by mass to 40% by mass.

8. The stretched substrate according to claim 5 , further comprising an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer.

9. a first surface resin layer containing polyethylene and an adhesive resin; one or more polyethylene intermediate layers containing polyethylene as a main component; a second surface resin layer containing polyethylene and an adhesive resin; In this order, The polyethylene in at least one layer selected from the first surface resin layer, the polyethylene intermediate layer, and the second surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or 3 Super 0.960g / cm 3 having a density of Stretched base material.

10. The stretched substrate according to claim 9, wherein the first surface resin layer and the second surface resin layer each independently have a polyethylene content of 60% by mass or more and 95% by mass or less and a adhesive resin content of 5% by mass or more and 40% by mass or less.

11. A first surface resin layer containing polyethylene as a main component; one or more polyethylene intermediate layers containing polyethylene as a main component; a second surface resin layer containing a gas barrier resin as a main component or containing polyethylene and an adhesive resin; In this order, The polyethylene in at least one layer selected from the first surface resin layer, the polyethylene intermediate layer, and the second surface resin layer contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, or 3 Super 0.960g / cm 3 having a density of Stretched base material.

12. The stretching substrate according to claim 11, wherein the gas barrier resin in the second surface resin layer contains at least one selected from an ethylene-vinyl alcohol copolymer and a polyamide.

13. The stretched substrate according to claim 11 , wherein the gas barrier resin in the second surface resin layer comprises an aromatic polyamide.

14. The stretched substrate according to claim 11, wherein the second surface resin layer has a polyethylene content of 60% by mass or more and 95% by mass or less, and a adhesive resin content of 5% by mass or more and 40% by mass or less.

15. The stretched substrate according to claim 11, wherein the second surface resin layer contains the gas barrier resin as a main component, and the stretched substrate further comprises an adhesive resin layer between the polyethylene intermediate layer and the second surface resin layer.

16. The stretched substrate according to any one of claims 1 to 15, wherein the stretched substrate is a stretched film of a coextruded resin film.

17. Stretched substrate according to any one of claims 1 to 15, wherein the stretched substrate is a biaxially stretched substrate.

18. The stretched substrate according to any one of claims 1 to 15, wherein at least one of the polyethylene intermediate layers contains at least one polyethylene selected from high density polyethylene and medium density polyethylene, and linear low density polyethylene.

19. The stretched substrate according to claim 18, wherein the total content of high density polyethylene and medium density polyethylene in at least one of the polyethylene intermediate layers is 20% by mass or more and 60% by mass or less, and the content of linear low density polyethylene is 40% by mass or more and 80% by mass or less.

20. The high density polyethylene has a viscosity of 0.945 g / cm 3 Super 0.960g / cm 3 The linear low density polyethylene is an ethylene-α-olefin copolymer having a density of 0.930 g / cm or less, 3 20. The oriented substrate of claim 18, which is an ethylene-α-olefin copolymer having a density of:

21. The stretched substrate according to any one of claims 1 to 10, and a vapor-deposited film provided on the surface of at least one layer selected from the first surface resin layer and the second surface resin layer of the stretched substrate, or The stretched substrate according to any one of claims 11 to 15, and a vapor deposition film provided on the surface of the second surface resin layer of the stretched substrate. Barrier substrate.

22. A first vapor-deposited film; A stretched substrate according to any one of claims 1 to 10, A second deposited film; In this order, the first vapor-deposited film is provided on a surface of the first surface resin layer, The second vapor-deposited film is provided on a surface of the second surface resin layer. Barrier substrate.

23. The barrier substrate according to claim 21 ; A heat seal layer; A laminate comprising at least

24. The laminate according to claim 23, wherein the heat seal layer contains polyethylene as a main component, and the content of polyethylene in the entire laminate is 80 mass % or more.

25. a first heat seal layer; The barrier substrate; a second heat seal layer; In this order, The laminate of claim 23.

26. A packaging container comprising the laminate according to claim 23.

27. 27. The packaging container of claim 26, which is a packaging bag.

28. A tube container body having a head and a body, The head portion includes a shoulder portion connected to one end of the body portion and a spout portion connected to the shoulder portion, and the body portion is formed of the laminated body according to claim 25. Tube container body.

29. The tube container body according to claim 28, Cap and A tube container comprising:

Images