Vapor-deposited film, laminate, packaging material, and packaging container

Abstract

To provide a vapor-deposited film having a resin substrate including a polyolefin resin layer and a polyamide resin layer and a vapor-deposited membrane, the vapor-deposited film excellent in gas barrier properties.SOLUTION: A vapor-deposited film includes a resin substrate and a vapor-deposited membrane. The resin substrate includes a polyolefin resin layer and a polyamide resin layer. The vapor-deposited membrane is disposed on the polyamide resin layer. The polyamide resin layer contains aliphatic polyamide and semi-aromatic polyamide.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vapor-deposited film, a laminate, a packaging material, and a packaging container. [Background technology]

[0002] Films made of polyesters such as polyethylene terephthalate (hereinafter also referred to as "polyester films") are inexpensive and have excellent mechanical properties, chemical stability, heat resistance, and transparency. For these reasons, polyester films have conventionally been used as substrates for forming laminates used in the production of packaging containers.

[0003] Depending on the contents to be filled in the packaging container, the packaging container is required to have gas barrier properties such as oxygen barrier property and water vapor barrier property. To meet this requirement, a vapor-deposited film is formed on the surface of a polyester film (Patent Document 1).

[0004] In recent years, resin substrates that can replace polyester films as substrates on which vapor-deposited films are formed have been sought. From the viewpoint of recyclability and the like, the use of polyolefin films, particularly polyethylene films, as such substrates has been considered. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-053223 Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventors have investigated the use of a polyolefin film as a resin substrate on which a vapor-deposited film is formed, instead of a conventional polyester film. As a result of their investigation, the present inventors have found that gas barrier properties can be improved by forming a vapor-deposited film on the polyamide resin layer of a resin substrate comprising a polyolefin resin layer and a polyamide resin layer. The present inventors have also investigated whether the gas barrier properties can be further improved by adjusting the composition of the polyamide resin layer.

[0007] One problem to be solved by the present disclosure is to provide a vapor-deposited film that includes a resin substrate containing a polyolefin resin layer and a polyamide resin layer and a vapor-deposited film, and that has excellent gas barrier properties. [Means for solving the problem]

[0008] The vapor-deposited film of the present disclosure comprises a resin substrate and a vapor-deposited film, the resin substrate comprising a polyolefin resin layer and a polyamide resin layer, the vapor-deposited film being provided on the polyamide resin layer, and the polyamide resin layer containing an aliphatic polyamide and a semi-aromatic polyamide. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a vapor-deposited film having an excellent gas barrier property, the vapor-deposited film including a resin substrate containing a polyolefin resin layer and a polyamide resin layer. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of the vapor-deposited film of the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view showing one embodiment of the vapor-deposited film of the present disclosure. [Figure 3] FIG. 3 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 4] FIG. 4 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 5]FIG. 5 is a schematic cross-sectional view showing one embodiment of the laminate of the present disclosure. [Figure 6] FIG. 6 is a schematic top view showing a cut portion in a stretched film. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Vapor-deposited film] The vapor-deposited film of the present disclosure includes a resin substrate and a vapor-deposited film. The resin substrate includes a polyolefin resin layer and a polyamide resin layer. The vapor-deposited film is provided on the polyamide resin layer. In one embodiment, the resin substrate further includes an adhesive resin layer between the polyolefin resin layer and the polyamide resin layer.

[0012] In the present disclosure, the term "film" is not particularly distinguished from the term "sheet."

[0013] Figure 1 shows one embodiment of a vapor-deposited film according to the present disclosure. The vapor-deposited film 1 shown in Figure 1 comprises a resin substrate 10 and a vapor-deposited film 20. The resin substrate 10 comprises a polyolefin resin layer 12 and a polyamide resin layer 14, in this order in the thickness direction. The vapor-deposited film 1 in Figure 1 comprises a polyolefin resin layer 12, a polyamide resin layer 14, and a vapor-deposited film 20, in this order in the thickness direction.

[0014] One embodiment of the vapor-deposited film of the present disclosure is shown in Figure 2. The vapor-deposited film 1 shown in Figure 2 is similar to that shown in Figure 1, except that the resin substrate 10 further includes an adhesive resin layer 13 between the polyolefin resin layer 12 and the polyamide resin layer 14. The vapor-deposited film 1 in Figure 2 includes the polyolefin resin layer 12, the adhesive resin layer 13, the polyamide resin layer 14, and a vapor-deposited film 20, in this order in the thickness direction.

[0015] 1 and 2, the vapor-deposited film 1 may further include a printed layer (not shown). The printed layer may be provided, for example, on the surface of the polyolefin resin layer 12 opposite to the surface facing the vapor-deposited film 20. The printed layer may be provided, for example, on the surface of the vapor-deposited film 20 opposite to the surface facing the polyolefin resin layer 12. In this case, a barrier coat layer (described later) may be provided between the vapor-deposited film 20 and the printed layer.

[0016] <Polyolefin resin layer> The resin substrate includes a polyolefin resin layer. The polyolefin resin layer contains a polyolefin. Examples of polyolefins include polyethylene, polypropylene, and polymethylpentene. Among these, polyethylene and polypropylene are preferred, and polyethylene is more preferred. That is, the polyolefin resin layer is preferably a polyethylene resin layer or a polypropylene resin layer, and more preferably a polyethylene resin layer.

[0017] In the present disclosure, polyethylene refers to a polymer in which the content of ethylene-derived structural units in all repeating structural units is 50 mol% or more. 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 can be measured by NMR.

[0018] In the present disclosure, the 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 2 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.

[0019] Specific examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and very low-density polyethylene. Among these, high-density polyethylene and medium-density polyethylene are preferred from the viewpoint of the strength and heat resistance of the resin substrate, and medium-density polyethylene is more preferred from the viewpoint of stretchability.

[0020] The density of the high density polyethylene is preferably 0.945 g / cm 3 The upper limit of the density of high density polyethylene is, for example, 0.965 g / cm 3 The density of the medium density polyethylene is preferably 0.925 g / cm 3 Exceeds 0.945g / cm 3 The density of the low density polyethylene is preferably 0.900 g / cm or less. 3 Exceeds 0.925g / cm 3 The low-density polyethylene is usually polyethylene obtained by polymerizing ethylene by a high-pressure polymerization method. The density of the linear low-density polyethylene is preferably 0.900 g / cm 3 Exceeds 0.925g / cm 3The linear low-density polyethylene is usually polyethylene obtained by polymerizing ethylene and a small amount of α-olefin by a low-pressure polymerization method (e.g., a polymerization method using a Ziegler-Natta catalyst or a metallocene catalyst). The density of the ultra-low-density polyethylene is preferably 0.900 g / cm 3 The lower limit of the density of the ultra-low density polyethylene is, for example, 0.860 g / cm 3 The density of polyethylene is measured in accordance with JIS K7112 (1999), particularly Method D (density gradient tube method, 23°C).

[0021] From the viewpoint of film-forming properties and processability, the melt flow rate (MFR) of the polyethylene is preferably 0.1 g / 10 min or more and 50 g / 10 min or less, more preferably 0.3 g / 10 min or more and 30 g / 10 min or less, even more preferably 0.5 g / 10 min or more and 10 g / 10 min or less, and particularly preferably 0.5 g / 10 min or more and 5.0 g / 10 min or less. In the present disclosure, the MFR of the polyethylene is measured in accordance with ASTM D1238 at a temperature of 190°C and a load of 2.16 kg.

[0022] The melting point (Tm) of the polyethylene is preferably 100° C. or higher and 140° C. or lower, more preferably 110° C. or higher and 138° C. or lower, and even more preferably 120° C. or higher and 135° C. or lower. In the present disclosure, Tm is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121.

[0023] The polypropylene may be any of a propylene homopolymer, a propylene random copolymer, and a propylene block copolymer. A propylene homopolymer is a polymer of propylene alone. A propylene random copolymer is a random copolymer of propylene and an ethylenically unsaturated monomer other than propylene (e.g., the above-mentioned α-olefins such as ethylene, 1-butene, and 4-methyl-1-pentene). A propylene block copolymer is a copolymer having a polymer block of propylene and a polymer block of an ethylenically unsaturated monomer other than propylene (e.g., the above-mentioned α-olefins such as ethylene, 1-butene, and 4-methyl-1-pentene). For example, it is preferable to use a homopolymer when the rigidity and heat resistance of the resin substrate are important, and to use a random copolymer when the impact resistance of the resin substrate is important.

[0024] In the present disclosure, polypropylene refers to a polymer in which the content of propylene-derived structural units in all repeating structural units is 50 mol% or more. In this polymer, the content of propylene-derived structural units is preferably 70 mol% or more, more preferably 80 mol% or more. The content can be measured by NMR.

[0025] From the viewpoint of film-forming properties and processability, the MFR of polypropylene is preferably 0.1 g / 10 min or more and 50 g / 10 min or less, more preferably 0.3 g / 10 min or more and 30 g / 10 min or less. In the present disclosure, the MFR of polypropylene is measured in accordance with ASTM D1238 at a temperature of 230°C and a load of 2.16 kg.

[0026] Polyolefins with different densities or branching can be obtained by appropriately selecting a polymerization method, such as gas-phase polymerization, slurry polymerization, solution polymerization, or high-pressure ionic polymerization, using a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst.

[0027] A single-site catalyst is a catalyst capable of forming a uniform active species, and is usually prepared by contacting a metallocene transition metal compound or a non-metallocene transition metal compound with an activating cocatalyst. Single-site catalysts are preferred because they have a more uniform structure of the active site than multi-site catalysts, making it possible to obtain polymers with high molecular weights and highly uniform structures.

[0028] The single-site catalyst is preferably a metallocene catalyst, which comprises a transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton, a cocatalyst, an organometallic compound as needed, and a support as needed.

[0029] Examples of the transition metal in the transition metal compound include zirconium, titanium, and hafnium, with zirconium and hafnium being preferred.

[0030] The cyclopentadienyl skeleton in the transition metal compound is a cyclopentadienyl group or a substituted cyclopentadienyl group. The substituted cyclopentadienyl group has at least one substituent selected from, for example, a hydrocarbon group having from 1 to 30 carbon atoms, a silyl group, a silyl-substituted alkyl group, a silyl-substituted aryl group, a cyano group, a cyanoalkyl group, a cyanoaryl group, a halogen group, a haloalkyl group, and a halosilyl group. The substituted cyclopentadienyl group has one or more substituents, and the substituents may be bonded to each other to form a ring, such as an indenyl ring, a fluorenyl ring, an azulenyl ring, or a hydrogenated product thereof. The ring formed by bonding the substituents to each other may further have a substituent.

[0031] The transition metal compound usually has two ligands having a cyclopentadienyl skeleton. The ligands having each cyclopentadienyl skeleton are preferably bonded to each other via a bridging group. Examples of the bridging group include alkylene groups having 1 to 4 carbon atoms, silylene groups, substituted silylene groups such as dialkylsilylene groups and diarylsilylene groups, and substituted germylene groups such as dialkylgermylene groups and diarylgermylene groups. Among these, substituted silylene groups are preferred.

[0032] The co-catalyst refers to a component that enables a transition metal compound of Group IV of the periodic table to function effectively as a polymerization catalyst or a component that balances the ionic charge in a catalytically activated state. Examples of the co-catalyst include benzene-soluble aluminoxanes or benzene-insoluble organoaluminum oxy-compounds, ion-exchangeable layered silicates, boron compounds, ionic compounds consisting of a cation with or without an active hydrogen group and a non-coordinating anion, lanthanoid salts such as lanthanum oxide, tin oxide, and phenoxy compounds containing a fluoro group.

[0033] Examples of organometallic compounds that may be used as needed include organoaluminum compounds, organomagnesium compounds, and organozinc compounds. Of these, organoaluminum compounds are preferred.

[0034] The transition metal compound may be used by being supported on an inorganic or organic carrier, preferably a porous oxide of an inorganic or organic compound, such as montmorillonite or other ion-exchangeable layered silicates, SiO2, Al2O3, MgO, ZrO2, TiO2, BO3, CaO, ZnO, BaO, ThO2, or mixtures thereof.

[0035] As the polyolefin, a biomass-derived polyolefin may be used. That is, as a raw material for obtaining the polyolefin, a biomass-derived olefin may be used instead of an olefin obtained from a fossil fuel. Since the biomass-derived polyolefin is a carbon-neutral material, the environmental impact of packaging materials can be reduced. The biomass-derived polyolefin (e.g., polyethylene) can be produced, for example, by the method described in JP 2013-177531 A. Commercially available biomass-derived polyolefin (e.g., Green PE commercially available from Braskem) may also be used.

[0036] Polyolefins recycled through mechanical or chemical recycling can be used as the polyolefin. This reduces the environmental impact of packaging materials. Mechanical recycling generally involves crushing recovered polyolefin film, washing it with alkali to remove dirt and foreign matter from the film surface, and then drying it at high temperature and reduced pressure for a certain period of time to disperse any contaminants remaining inside the film, decontaminating it, and returning it to polyolefin. Chemical recycling generally involves breaking down recovered polyolefin film to the monomer level and repolymerizing the monomer to obtain polyolefin. The above description of polyolefins is applicable to the polyolefins in the following description.

[0037] The polyolefin resin layer can contain one or more types of polyolefins. The polyolefin content in the polyolefin resin layer, for example, the polyethylene content or the polypropylene content, 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, which can improve, for example, the recyclability of the resin substrate.

[0038] The polyolefin resin layer may contain one or more additives, such as crosslinking agents, antiblocking agents, slip agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, dyes, and modifying resins.

[0039] The polyolefin resin layer may have a single-layer structure or a multi-layer structure of two or more layers. In one embodiment, the number of polyolefin resin layers is 2 to 7 or 3 to 5, specifically 3, 5, or 7. When the polyolefin resin layer has a multi-layer structure, for example, the balance between rigidity, strength, and heat resistance of the resin substrate can be improved.

[0040] In one embodiment, each layer constituting the polyolefin resin layer having a multilayer structure is also composed of a polyolefin. That is, the content of polyolefin in each layer, for example, the content of polyethylene or polypropylene, 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 can, for example, improve the recyclability of the resin substrate.

[0041] The thickness of the polyolefin resin layer before stretching is preferably 20 μm or more and 200 μm or less, more preferably 30 μm or more and 150 μm or less, and even more preferably 40 μm or more and 120 μm or less. The thickness of the polyolefin resin layer after stretching is preferably 5 μm or more and 50 μm or less, more preferably 8 μm or more and 40 μm or less, and even more preferably 10 μm or more and 30 μm or less. When the thickness of the polyolefin resin layer before or after stretching is equal to or greater than the lower limit, for example, the rigidity and strength of the resin substrate can be improved. When the thickness of the polyolefin resin layer before or after stretching is equal to or less than the upper limit, for example, the processability of the resin substrate can be improved.

[0042] <Polyamide resin layer> The resin substrate includes a polyamide resin layer. By forming a vapor-deposited film on the polyamide resin layer, gas barrier properties can be improved compared to forming a vapor-deposited film on a polyolefin resin layer. The reason for this is unclear, but the present inventors speculate as follows: Polyamide has a polar structure called an amide bond. The main chains of adjacent polyamides attract each other through hydrogen bonds or the like, restricting the mobility of the polar structure. Therefore, gas barrier properties are improved. Note that the above explanation is merely speculation and does not limit the present disclosure in any way.

[0043] In one embodiment, the polyamide resin layer constitutes a surface resin layer (outermost layer) on one side of the resin substrate. With such a configuration, for example, in addition to the above-mentioned gas barrier properties, the processability and heat resistance of the resin substrate can be improved.

[0044] The polyamide resin layer contains an aliphatic polyamide and a semi-aromatic polyamide. The polyamide resin layer can contain one or more aliphatic polyamides. The polyamide resin layer can contain one or more types of semi-aromatic polyamides.

[0045] The content of polyamides, including aliphatic polyamides and semi-aromatic polyamides, in the polyamide resin layer is preferably more than 50% by mass, more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, 85% by mass or more, 90% by mass or more, or 95% by mass or more.

[0046] Below, we will explain raw material monomers from which the structural units contained in polyamides can be derived, and then we will explain specific polyamides. Examples of raw material monomers include lactams, aminocarboxylic acids, diamines, and dicarboxylic acids. Polyamides can be obtained, for example, by ring-opening polymerization of lactams, polycondensation of aminocarboxylic acids, polycondensation of diamines and dicarboxylic acids, or combinations thereof.

[0047] Examples of lactams include γ-butyrolactam, δ-valerolactam, ε-caprolactam, enantholactam, undecane lactam, and dodecane lactam. Among these, ε-caprolactam, enantholactam, undecane lactam, and dodecane lactam are preferred. The number of carbon atoms in the lactam is, for example, 4 to 12.

[0048] Examples of aminocarboxylic acids include 6-aminocaproic acid, 7-aminoheptanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Among these, 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid are preferred. The number of carbon atoms in the aminocarboxylic acid is, for example, 6 to 12.

[0049] Examples of diamines include aliphatic diamines such as aliphatic chain diamines and alicyclic diamines, and aromatic diamines. The aliphatic diamines have, for example, 2 to 20 carbon atoms, preferably 4 to 12 carbon atoms.

[0050] Examples of the aliphatic chain diamine include aliphatic linear diamines and aliphatic branched diamines, such as ethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, tridecanediamine, tetradecanediamine, pentadecanediamine, hexadecanediamine, heptadecanediamine, octadecanediamine, nonadecanediamine, eicosanediamine, 2-methyl-1,5-pentanediamine, 2-methyl-1,8-octanediamine, and 2,2,4- / 2,4,4-trimethylhexamethylenediamine.

[0051] Examples of alicyclic diamines include 1,3- / 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, bis(4-aminocyclohexyl)propane, bis(3-methyl-4-aminocyclohexyl)methane, (3-methyl-4-aminocyclohexyl)propane, 1,3- / 1,4-bis(aminomethyl)cyclohexane, 5-amino-2,2,4-trimethyl-1-cyclopentanemethylamine, 5-amino-1,3,3-trimethylcyclohexanemethylamine, norbornanedimethyleneamine, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane.

[0052] Among the aliphatic diamines, aliphatic chain diamines are preferred, aliphatic straight-chain diamines are more preferred, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, nonamethylenediamine, decamethylenediamine and dodecamethylenediamine are further preferred, and hexamethylenediamine is particularly preferred.

[0053] Examples of aromatic diamines include phenylenediamines such as p-phenylenediamine and m-phenylenediamine; xylylenediamines such as p-xylylenediamine and m-xylylenediamine; tolylenediamines such as 2,4-tolylenediamine and 2,6-tolylenediamine; diaminonaphthalenes such as 1,4-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene and 2,6-diaminonaphthalene; 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, and 4,4'-diamino-3,3',5,5'-tetramethyl diaminodiphenylmethane compounds such as diphenylmethane, 4,4'-diamino-3,3',5,5'-tetraethyldiphenylmethane, and 4,4'-diamino-3,3'-dimethyl-5,5'-diethyldiphenylmethane; and bis(aminophenyl)propane compounds such as 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis(4-amino-3-methylphenyl)propane, 2,2'-bis(4-amino-3-ethylphenyl)propane, 2,2'-bis(4-amino-3,5-dimethylphenyl)propane, 2,2'-bis(4-amino-3,5-diethylphenyl)propane, and 2,2'-bis(4-amino-3-methyl-5-ethylphenyl)propane.

[0054] Among aromatic diamines, xylylenediamine is preferred, p-xylylenediamine and m-xylylenediamine are more preferred, and m-xylylenediamine is even more preferred.

[0055] Examples of dicarboxylic acids include aliphatic dicarboxylic acids such as aliphatic chain dicarboxylic acids and alicyclic dicarboxylic acids, and aromatic dicarboxylic acids. The aliphatic dicarboxylic acids have, for example, 2 to 20 carbon atoms, preferably 6 to 12 carbon atoms.

[0056] Examples of the aliphatic chain dicarboxylic acid include aliphatic linear dicarboxylic acids and aliphatic branched dicarboxylic acids, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, octadecanedioic acid, and eicosane dioic acid.

[0057] Alicyclic dicarboxylic acids include, for example, 1,3- / 1,4-cyclohexanedicarboxylic acid, dicyclohexanemethane-4,4'-dicarboxylic acid, and norbornanedicarboxylic acid.

[0058] Among the aliphatic dicarboxylic acids, aliphatic chain dicarboxylic acids are preferred, aliphatic straight-chain dicarboxylic acids are more preferred, adipic acid, azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid are further preferred, and adipic acid is particularly preferred.

[0059] Examples of aromatic dicarboxylic acids include phthalic acid compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid; naphthalenedicarboxylic acids such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; and diphenylmethanedicarboxylic acids such as diphenylmethane-2,4-dicarboxylic acid, diphenylmethane-3,3'-dicarboxylic acid, diphenylmethane-3,4'-dicarboxylic acid, and diphenylmethane-4,4'-dicarboxylic acid.

[0060] Among the aromatic dicarboxylic acids, phthalic acid compounds are preferred, with isophthalic acid and terephthalic acid being more preferred.

[0061] Polyamides include, for example, aliphatic polyamides and semi-aromatic polyamides.

[0062] Examples of aliphatic polyamides include aliphatic homopolyamides and aliphatic copolyamides. Aliphatic homopolyamides may be polyamides composed of one lactam or one aminocarboxylic acid, or polyamides composed of a combination of one aliphatic diamine and one aliphatic dicarboxylic acid. In the present disclosure, the latter case is also classified as a homopolyamide. Aliphatic copolyamides may be polyamides composed of two or more monomers selected from lactams and aminocarboxylic acids, polyamides composed of a combination of lactams and / or aminocarboxylic acids with aliphatic diamines and aliphatic dicarboxylic acids, or polyamides composed of a combination of one or more aliphatic diamines with one or more aliphatic dicarboxylic acids (excluding the combination of one aliphatic diamine and one aliphatic dicarboxylic acid).

[0063] In the following examples, polyamide is also referred to as "PA." Specific examples of aliphatic homopolyamides include polycaprolactam (PA6), polyenantholactam (PA7), polyundecane lactam (PA11), polylauryllactam (PA12), polyhexamethylene adipamide (PA66), polytetramethylene dodecamide (PA412), polypentamethylene azelamide (PA59), polypentamethylene sebacamide (PA510), polypentamethylene dodecamide (PA512), polyhexamethylene azelamide (PA69), polyhexamethylene sebacamide (PA610), polyhexamethylene dodecamide (PA612), poly Examples include nonamethylene adipamide (PA96), polynonameethylene azelamide (PA99), polynonameethylene sebacamide (PA910), polynonameethylene dodecamide (PA912), polydecamethylene adipamide (PA106), polydecamethylene azelamide (PA109), polydecamethylene decamide (PA1010), polydecamethylene dodecamide (PA1012), polydodecamethylene adipamide (PA126), polydodecamethylene azelamide (PA129), polydodecamethylene sebacamide (PA1210), and polydodecamethylene dodecamide (PA1212).

[0064] 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 Examples include 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), and caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminododecanedicarboxylic acid copolymer (PA6 / 66 / 612).

[0065] The relative viscosity of the aliphatic polyamide is preferably 1.5 to 5.0, more preferably 2.0 to 5.0, and even more preferably 2.5 to 4.5. The relative viscosity of the aliphatic polyamide is measured at 25°C in accordance with JIS K6920 by dissolving 1 g of polyamide in 100 mL of 96% concentrated sulfuric acid.

[0066] As the aliphatic polyamide, from the viewpoint of improving physical properties such as abrasion resistance, cold resistance, impact resistance, and oil resistance, crystalline aliphatic polyamides such as PA6, PA11, PA12, PA66, PA610, PA612, PA6 / 66, and PA6 / 66 / 12 are preferred.

[0067] The melting point (Tm) of the crystalline aliphatic polyamide is preferably 170°C or higher and 300°C or lower, more preferably 170°C or higher and 250°C or lower, even more preferably 170°C or higher and 230°C or lower, and particularly preferably 170°C or higher and 220°C or lower, 180°C or higher and 215°C or lower, or 180°C or higher and 210°C or lower. In the present disclosure, Tm is obtained by differential scanning calorimetry (DSC) in accordance with JIS K7121. If the Tm is low, for example, when polyethylene and polyamide are co-extruded to form a co-extruded resin film, the difference in melting points between the polyethylene and polyamide is small, thereby improving moldability.

[0068] The semi-aromatic polyamide is a polyamide having structural units derived from an aromatic diamine and structural units derived from an aliphatic dicarboxylic acid, or a polyamide having structural units derived from an aliphatic diamine and structural units derived from an aromatic dicarboxylic acid. Examples include polyamides composed of an aromatic diamine and an aliphatic dicarboxylic acid, and polyamides composed of an aliphatic diamine and an aromatic dicarboxylic acid.

[0069] In the polyamides composed of aromatic diamines and aliphatic dicarboxylic acids, the diamines do not all need to be aromatic diamines, and they may further contain structural units derived from aliphatic diamines.In the polyamides composed of aliphatic diamines and aromatic dicarboxylic acids, the dicarboxylic acids do not all need to be aromatic dicarboxylic acids, and they may further contain structural units derived from aliphatic dicarboxylic acids.These polyamides may further contain structural units derived from lactams and / or aminocarboxylic acids.

[0070] Specific 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 / polycaproamide copolymer (PA6I / 6), and polyhexamethylene terephthalamide / polycaproamide copolymer (PA6I / 6). Examples of suitable polyimide copolymers include lydodecaamide 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, PA6I / 6T and PAMXD6 are preferred, with PA6I / 6T being more preferred.

[0071] The melt volume rate (MVR) of the semi-aromatic polyamide is preferably 5 cm 3 / 10 minutes or more 200cm 3 / 10 minutes or less, preferably 10cm 3 / 100cm for more than 10 minutes 3 / 10 minutes or less, and from the viewpoint of film formation, it is more preferable that 3 / 50cm for more than 10 minutes 3 / 10 minutes or less. MVR is measured in accordance with ISO1133 at a temperature of 275°C and a load of 5 kg.

[0072] Semi-aromatic polyamides are preferred as gas barrier resins. The semi-aromatic polyamide may be an amorphous semi-aromatic polyamide such as PA6I / 6T, or a crystalline semi-aromatic polyamide such as PA6T, PA9T, PA6I, PAMXD6, etc. Among these, amorphous semi-aromatic polyamides are preferred from the viewpoints of gas barrier properties and transparency.

[0073] The amorphous polyamide means a polyamide that does not have a clear melting point, specifically, a polyamide having a crystalline melting enthalpy ΔHm of 5 J / g or less, preferably 3 J / g or less, and more preferably 1 J / g or less. The crystalline melting enthalpy is measured by differential scanning calorimetry (DSC) in accordance with JIS K7121 and JIS K7122.

[0074] As the amorphous semi-aromatic polyamide, a semi-aromatic polyamide having two or more structural units derived from aromatic dicarboxylic acids is preferred, and a polyamide having, as the dicarboxylic acid component, structural units derived from isophthalic acid and structural units derived from terephthalic acid, and as the diamine component, structural units derived from aliphatic diamine (hereinafter also referred to as "polyamide (a)") is more preferred.

[0075] In the polyamide (a), the proportion of structural units derived from isophthalic acid in 100 mol % of structural units derived from dicarboxylic acids is preferably 40 mol % to 98 mol %, more preferably 50 mol % to 80 mol %, and the proportion of structural units derived from terephthalic acid is preferably 2 mol % to 60 mol %, more preferably 20 mol % to 50 mol %. The proportions can be measured by NMR.

[0076] In the polyamide (a), the total proportion of structural units derived from isophthalic acid and structural units derived from terephthalic acid in 100 mol% of structural units derived from dicarboxylic acids is preferably 60 mol% or more, more preferably 70 mol% or more, even more preferably 80 mol% or more, particularly preferably 90 mol% or more, 95 mol% or more, or 98 mol% or more. The polyamide (a) may contain structural units derived from dicarboxylic acids other than isophthalic acid and terephthalic acid (e.g., adipic acid) as necessary.

[0077] The polyamide (a) preferably contains a structural unit derived from hexamethylenediamine as a diamine component. In the polyamide (a), the proportion of the structural units derived from hexamethylenediamine in 100 mol% of the structural units derived from diamine is preferably 60 mol% or more, more preferably 70 mol% or more, even more preferably 80 mol% or more, particularly preferably 90 mol% or more, 95 mol% or more, or 98 mol% or more. The polyamide (a) may contain a structural unit derived from a diamine other than hexamethylenediamine, as necessary. The polyamide (a) is preferably PA6I / 6T.

[0078] The glass transition temperature (Tg) of the amorphous semi-aromatic polyamide is, for example, 90° C. or more and 180° C. or less, preferably 95° C. or more and 160° C. or less, and more preferably 100° C. or more and 150° C. or less. Tg is measured by differential scanning calorimetry (DSC) in accordance with JIS K7121.

[0079] The polyamide resin layer contains an aliphatic polyamide as the polyamide. The content of the aliphatic polyamide in the polyamide resin layer is preferably more than 50% by mass, more preferably 60% by mass or more, and even more preferably 70% by mass or more. The upper limit of the content of the aliphatic polyamide is, for example, 99%, 95%, or 90% by mass.

[0080] The polyamide resin layer contains an aliphatic polyamide and a semi-aromatic polyamide as a barrier modifier. This configuration can improve, for example, the gas barrier properties of the vapor-deposited film, specifically the oxygen barrier properties and water vapor barrier properties. While the reason for this is unclear, the present inventors speculate as follows: Polyamides have amide bonds and are typically hydrophilic, so they are humidity-dependent. For example, high humidity can reduce the gas barrier properties of polyamides. Semi-aromatic polyamides have aromatic rings in addition to amide bonds. The stacking effect of the aromatic rings can narrow the intermolecular gap. Therefore, the addition of semi-aromatic polyamides improves gas barrier properties. Note that the above explanation is speculation and does not limit the present disclosure in any way.

[0081] The content of the semi-aromatic polyamide in the polyamide resin layer is preferably 1 part by mass to 100 parts by mass, more preferably 5 parts by mass to 60 parts by mass, even more preferably 10 parts by mass to 50 parts by mass, and particularly preferably 15 parts by mass to 40 parts by mass, relative to 100 parts by mass of the aliphatic polyamide. Such a configuration can improve, for example, the gas barrier property.

[0082] In one embodiment, the polyamide resin layer contains a crystalline aliphatic polyamide and an amorphous semi-aromatic polyamide, which can improve, for example, the stretchability of the resin substrate, the surface smoothness of the resin substrate before and after stretching, the curl suppression of a stretched film (described later), and the gas barrier properties and gloss of a vapor-deposited film, as described below.

[0083] Adding an amorphous semi-aromatic polyamide to a polyamide resin layer can improve the stretchability of the resin substrate, for example. The reason for this is unclear, but the present inventors speculate as follows. In one embodiment, stretching is performed at a temperature at which the polyolefin resin layer (particularly the polyethylene resin layer) softens. The molecular chains of amorphous semi-aromatic polyamides are more mobile than those of crystalline aliphatic polyamides. In one embodiment, the glass transition temperature of amorphous semi-aromatic polyamides is close to the melting point region of polyethylene. Therefore, during stretching, the polyamide resin layer containing amorphous semi-aromatic polyamides easily conforms to the polyolefin resin layer. This improves stretchability. Note that the above explanation is merely speculation and does not limit the present disclosure in any way.

[0084] By adding an amorphous semi-aromatic polyamide to the polyamide resin layer, for example, the surface smoothness of the polyamide resin layer before stretching can be improved, and the surface smoothness can be further improved by stretching. With the improvement in surface smoothness, for example, the gloss of the vapor-deposited film can be improved and the reflective haze can be reduced.

[0085] The surface roughness (Ra) of the polyamide resin layer in the stretched film is preferably 12 nm or less, more preferably 1.0 nm or more and 10 nm or less, and even more preferably 2.0 nm or more and 8.0 nm or less, or 2.0 nm or more and 7.5 nm or less. The surface roughness (Ra) is the arithmetic mean surface roughness (Ra) measured in accordance with JIS B0601:2013.

[0086] The 20° gloss of the vapor-deposited film is preferably 1660 GU or more, more preferably 1680 GU or more, and even more preferably 1690 GU or more. There is no particular upper limit to the 20° gloss, but it may be, for example, 1950 GU. The 20° gloss is measured in accordance with JIS Z8741, with the center of the light-receiving angle set to 20° and the light-receiving angle width set to 0.9°. Gloss indicates the intensity of specularly reflected light from an object surface, with a higher value indicating higher gloss.

[0087] The specular reflection peak (Rspec) of the vapor-deposited film is preferably 1430 GU or higher, more preferably 1450 GU or higher, and even more preferably 1470 GU or higher. The upper limit of the specular reflection peak is 2000 GU. The center of the light-receiving angle is 20°, and the light-receiving angle width is 0.2°. The specular reflection peak indicates glossiness over a narrower range than the glossiness described above, and therefore makes it possible to capture the surface condition locally. The larger the specular reflection peak, the higher the glossiness.

[0088] The reflective haze of the vapor-deposited film is preferably 20 or less, more preferably 18 or less, and even more preferably 15 or less. The lower limit of reflective haze is preferable, but it may be, for example, 1, 3, 5, or 7. Reflective haze is measured at an incident angle of 20°±1.8° in accordance with ASTM E430 and is calculated as the ratio of the amount of specularly reflected light (20°±1.8°) to the amount of light dispersed at angles of 18.1°±1.8° and 21.9°±1.8°, which cause haze. Reflective haze indicates the degree of cloudiness of the surface. Details of the conditions for measuring the above physical properties are described in the Examples section.

[0089] When a resin substrate has a polyamide resin layer as a surface resin layer on one side, the symmetry of the resin substrate in the thickness direction is reduced, which can lead to curling of the stretched film. Here, adding an amorphous semi-aromatic polyamide to a polyamide resin layer containing a crystalline aliphatic polyamide can effectively suppress curling of the stretched film. While the reason for this is unclear, the present inventors speculate as follows: Because crystalline polyamide is a crystalline polymer, it experiences significant volumetric shrinkage upon solidification. By blending a crystalline aliphatic polyamide with an amorphous semi-aromatic polyamide, this volumetric shrinkage can be suppressed. Furthermore, by blending a crystalline aliphatic polyamide with an amorphous semi-aromatic polyamide, the crystallinity and crystallization rate of the crystalline aliphatic polyamide can be adjusted. This is thought to have led to suppression of curling and improved smoothness and gloss. The above explanation is merely speculation and does not limit the present disclosure in any way.

[0090] The content of the amorphous semi-aromatic polyamide in the polyamide resin layer is preferably 1 part by mass to 100 parts by mass, more preferably 5 parts by mass to 60 parts by mass, even more preferably 10 parts by mass to 50 parts by mass, and particularly preferably 15 parts by mass to 40 parts by mass, relative to 100 parts by mass of the crystalline aliphatic polyamide. Such a configuration can improve, for example, the above-mentioned physical properties.

[0091] In one embodiment, the polyolefin resin layer is a polyethylene resin layer containing polyethylene, and the polyamide resin layer contains a crystalline aliphatic polyamide. In the resin substrate, the difference (Tm1 - Tm2) between the melting point (Tm1) of the crystalline aliphatic polyamide contained in the polyamide resin layer and the melting point (Tm2) of the polyethylene contained in the polyethylene resin layer is preferably 90°C or less, more preferably 80°C or less, and even more preferably 75°C or less. This embodiment can improve the film-forming suitability, for example, when the resin substrate is produced by coextrusion. The lower limit of this difference is, for example, 30°C, 40°C, or 50°C.

[0092] The polyamide resin layer may contain one or more additives, such as crosslinking agents, antiblocking agents, slip agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, dyes, and modifying resins.

[0093] Examples of lubricants include hydrocarbon lubricants, fatty acid lubricants, fatty acid amide lubricants, ester lubricants, and metal soaps. The lubricant may be liquid or solid.

[0094] Examples of hydrocarbon lubricants include liquid paraffin, natural paraffin, polyethylene wax, and microcrystalline wax. Examples of fatty acid lubricants include stearic acid and lauric acid. Examples of fatty acid amide lubricants include stearic acid amide, palmitic acid amide, N-oleyl palmitic acid amide, behenic acid amide, erucic acid amide, arachidic acid amide, oleic acid amide, methylene bisstearamide, and ethylene bisstearamide. Examples of ester lubricants include butyl stearate, hydrogenated castor oil, ethylene glycol monostearate, and stearate monoglyceride. Examples of metal soaps include zinc stearate and calcium stearate.

[0095] The thickness of the polyamide resin layer before stretching is preferably 3 μm to 50 μm, more preferably 4 μm to 30 μm, and even more preferably 5 μm to 20 μm. The thickness of the polyamide resin layer after stretching is preferably 0.5 μm to 20 μm, more preferably 0.8 μm to 15 μm, and even more preferably 1.2 μm to 10 μm. When the thickness of the polyamide resin layer before or after stretching is equal to or greater than the lower limit, for example, the adhesion of the vapor-deposited film and the gas barrier properties of the vapor-deposited film can be improved, and the rigidity and strength of the resin substrate can be improved. When the thickness of the polyamide resin layer before or after stretching is equal to or less than the upper limit, for example, the processability of the resin substrate can be improved.

[0096] The ratio of the thickness of the polyamide resin layer to the total thickness of the resin substrate is preferably 1% to 25%, more preferably 3% to 20%, and even more preferably 5% to 15%. This configuration can improve, for example, the adhesion of the vapor-deposited film and the gas barrier properties of the vapor-deposited film, and can also improve the recyclability of mono-material packaging materials produced using the resin substrate.

[0097] <Adhesive resin layer> In one embodiment, the resin substrate includes an adhesive resin layer between the polyolefin resin layer and the polyamide resin layer, which can improve adhesion between the polyolefin resin layer and the polyamide resin layer, for example.

[0098] The adhesive resin layer is composed of, for example, an adhesive resin. Examples of adhesive resins include polyolefins, modified polyolefins, vinyl resins, polyethers, polyesters, polyurethanes, silicone resins, epoxy resins, and phenolic resins. Examples of modified polyolefins include modified polyolefins, particularly acid-modified polyolefins. Examples of modified polyolefins include graft-modified polyolefins with unsaturated carboxylic acids such as maleic acid and fumaric acid, or their acid anhydrides, esters, or metal salts. Among adhesive resins, modified polyolefins are preferred, and modified polyethylene and modified polypropylene are more preferred, from the viewpoint of obtaining a structure suitable for monomaterial packaging materials.

[0099] From the viewpoint of film-forming properties and processability, the melt flow rate (MFR) of the modified polyolefin is preferably 0.1 g / 10 min or more and 50 g / 10 min or less, more preferably 0.3 g / 10 min or more and 30 g / 10 min or less, even more preferably 0.5 g / 10 min or more and 10 g / 10 min or less, and particularly preferably 0.5 g / 10 min or more and 5.0 g / 10 min or less.

[0100] The adhesive resin layer can contain one or more adhesive resins. The thickness of the adhesive resin layer is, for example, 1 μm or more and 15 μm or less.

[0101] The ratio of the thickness of the adhesive resin layer to the total thickness of the resin substrate is preferably 1% to 25%, more preferably 3% to 20%, and even more preferably 5% to 15%. This configuration can improve the recyclability of, for example, mono-material packaging materials produced using the resin substrate.

[0102] <Resin substrate> In one embodiment, the resin substrate is a coextruded resin film, and each layer constituting the resin substrate is a coextruded resin layer. The resin substrate can be produced by film formation using, for example, an inflation method or a T-die method.

[0103] The total thickness of the resin substrate before stretching is preferably 30 μm to 300 μm, more preferably 40 μm to 250 μm, and even more preferably 50 μm to 200 μm. The total thickness of the resin substrate after stretching is preferably 6 μm to 80 μm, more preferably 10 μm to 60 μm, and even more preferably 12 μm to 50 μm.

[0104] In the present disclosure, a resin substrate including a polyolefin resin layer, an adhesive resin layer if necessary, and a polyamide resin layer is preferably subjected to a stretching treatment before a vapor-deposited film is formed. A resin substrate that has been stretched is also called a "stretched film." By stretching the polyamide resin layer on which a vapor-deposited film is formed, for example, the surface smoothness of the polyamide resin layer can be improved, and therefore the gloss of the vapor-deposited film can be improved.

[0105] The stretching treatment can improve the heat resistance and strength of the resin substrate. The stretching may be uniaxial or biaxial, and in one embodiment, it is uniaxial. In one embodiment, the stretched film is a uniaxially stretched film, more specifically, a uniaxially stretched film stretched in the machine direction (MD).

[0106] In one embodiment, the stretching ratio in the machine direction (MD) of the stretched film is preferably 2 to 10, more preferably 3 to 7. In one embodiment, the stretching ratio in the transverse direction (TD) of the stretched film is preferably 2 to 10, more preferably 3 to 7.

[0107] When the stretching ratio is 2 times or more, for example, the rigidity, strength, and heat resistance of the resin substrate can be improved, and the transparency of the resin substrate can be improved.When the stretching ratio is 10 times or less, for example, good stretching can be performed without causing breakage of the film.

[0108] Stretched films can be produced, for example, by forming a laminate from multiple resin materials or resin compositions using an inflation method or a T-die method, and then stretching the resulting laminate. The stretching process can improve the transparency, rigidity, strength, and heat resistance of the resin substrate. The inflation film-forming machine can also stretch the laminate. This allows for the production of stretched films, thereby improving production efficiency.

[0109] In one embodiment, the stretched film is obtained by stretching a laminate (precursor) including a polyolefin resin layer, and optionally an adhesive resin layer and a polyamide resin layer. Specifically, the layers are co-extruded into a tubular shape to produce a laminate. By producing a laminate using this method, the number of defective products can be reduced and production efficiency can be improved.

[0110] For example, when the polyolefin resin layer is a polyethylene resin layer and the resin substrate is produced by the T-die method, the melt flow rate (MFR) of the polyethylene constituting the polyethylene resin layer is preferably 3.0 g / 10 min or more and 20 g / 10 min or less from the viewpoint of film-forming properties and processability.

[0111] For example, when the polyolefin resin layer is a polyethylene resin layer and the resin substrate is produced by an inflation method, the MFR of the polyethylene constituting the polyethylene resin layer is preferably 0.5 g / 10 min or more and 5.0 g / 10 min or less from the viewpoints of film-forming properties and processability.

[0112] In one embodiment, the haze value of the stretched film is 20% or less, preferably 15% or less, and more preferably 13% or less. A smaller haze value is preferable, but in one embodiment, the lower limit may be 0.1%, 1%, or 3%. The haze value of the stretched film is measured in accordance with JIS K7136.

[0113] <Vapor deposition film> The vapor-deposited film of the present disclosure includes a vapor-deposited film on a polyamide resin layer, specifically on the surface of the polyamide resin layer opposite to the surface on which the polyolefin resin layer is provided, which can improve, for example, the gas barrier property, specifically the oxygen barrier property and water vapor barrier property, of the vapor-deposited film.

[0114] The vapor-deposited film is composed of, for example, metals such as aluminum, chromium, tin, nickel, copper, silver, gold, and platinum; or inorganic oxides such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide. Among these, metal vapor-deposited films such as aluminum (Al) vapor-deposited films, and inorganic oxide vapor-deposited films such as aluminum oxide (alumina) vapor-deposited films and silicon oxide (silica) vapor-deposited films are preferred.

[0115] The thickness of the vapor-deposited film is preferably 1 nm or more and 150 nm or less, more preferably 5 nm or more and 60 nm or less, and even more preferably 10 nm or more and 40 nm or less. By making the thickness of the vapor-deposited film equal to or greater than the lower limit, for example, the oxygen barrier property and water vapor barrier property of the vapor-deposited film can be further improved. By making the thickness of the vapor-deposited film equal to or less than the upper limit, for example, the occurrence of cracks in the vapor-deposited film can be suppressed and the recyclability of the laminate can be improved.

[0116] Examples of methods for forming a vapor-deposited film include physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, and ion plating; and chemical vapor deposition (CVD) methods such as plasma-enhanced chemical vapor deposition, thermal chemical vapor deposition, and photochemical vapor deposition. The vapor-deposited film may be a composite film containing two or more vapor-deposited films of different inorganic oxides, formed by combining both physical vapor deposition and chemical vapor deposition.

[0117] The vacuum level in the deposition chamber was 10 -2 ~10 -8 After oxygen is introduced, the pressure is preferably about 10 -1 ~10 -6The pressure is preferably about 100 mbar. The amount of oxygen introduced varies depending on the size of the deposition machine. An inert gas such as argon gas, helium gas, or nitrogen gas may be used as a carrier gas for the oxygen introduced, provided that no problems occur. The conveying speed of the resin substrate on which the deposited film is formed is, for example, 10 m / min or more and 800 m / min or less.

[0118] The surface of the vapor-deposited film may be subjected to a surface treatment. This can improve the adhesion between the vapor-deposited film and a layer adjacent to the vapor-deposited film. Examples of surface treatment methods include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using gases such as oxygen gas and nitrogen gas, and glow discharge treatment; and chemical treatments such as oxidation treatment using chemicals.

[0119] A barrier coat layer may be provided on the surface of the vapor-deposited film. With this configuration, for example, when the vapor-deposited film is composed of an inorganic oxide such as aluminum oxide or silicon oxide, the gas barrier properties and printability of the vapor-deposited film can be effectively improved, and the occurrence of cracks in the vapor-deposited film can be effectively suppressed. In one embodiment, the vapor-deposited film of the present disclosure includes a polyolefin resin layer, an adhesive resin layer (if necessary), a polyamide resin layer, a vapor-deposited film, and a barrier coat layer, arranged in this order in the thickness direction.

[0120] In one embodiment, the barrier coat layer is made of a gas barrier resin, such as an ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyacrylonitrile, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyamides such as nylon 6, nylon 6,6, and polymetaxylylene adipamide, polyurethane, and polyvinylidene chloride.

[0121] The content of the gas barrier resin in the barrier coat layer is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. Such a configuration can improve, for example, the gas barrier properties of the barrier coat layer.

[0122] The thickness of the barrier coat layer is preferably 0.01 μm or more and 10 μm or less, more preferably 0.1 μm or more and 5 μm or less. By making the thickness of the barrier coat layer 0.01 μm or more, for example, the gas barrier property can be further improved.

[0123] The barrier coat layer can be formed, for example, by dissolving or dispersing a material such as a gas barrier resin in water or an appropriate organic solvent, applying the resulting coating liquid, and drying it.

[0124] In another embodiment, the barrier coat layer is a gas barrier coating layer formed by mixing an alkoxide, a water-soluble polymer, and optionally a silane coupling agent, and then adding water, an organic solvent, and a sol-gel catalyst to obtain a gas barrier composition, which is then coated on a vapor-deposited film and dried. The gas barrier coating layer contains a hydrolysis polycondensate obtained by hydrolyzing and polycondensing the alkoxide or the like by a sol-gel method. Each of the above components can be used alone or in combination of two or more.

[0125] The alkoxide is represented by, for example, formula (1). R 1 n M(OR 2 ) m (1) In formula (1), R 1 and R 2 each independently represents an organic group having 1 to 8 carbon atoms; M represents a metal atom; n represents an integer of 0 or more; m represents an integer of 1 or more; and n+m represents the valence of M.

[0126] R 1 and R 2 Examples of the organic group include alkyl groups having 1 to 8 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an n-hexyl group, and an n-octyl group. The metal atom M is, for example, silicon, zirconium, titanium or aluminum.

[0127] Examples of the alkoxide represented by formula (1) include alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane.

[0128] Examples of water-soluble polymers include water-soluble polymers having hydroxyl groups, such as polyvinyl alcohol and ethylene-vinyl alcohol copolymers. Depending on the desired physical properties, such as oxygen barrier property, water vapor barrier property, water resistance, and weather resistance, either polyvinyl alcohol or ethylene-vinyl alcohol copolymer may be used, or both may be used in combination. Alternatively, a gas barrier coating layer obtained using polyvinyl alcohol and a gas barrier coating layer obtained using ethylene-vinyl alcohol copolymer may be laminated. The amount of water-soluble polymer used is preferably 5 to 500 parts by mass per 100 parts by mass of the alkoxide represented by formula (1).

[0129] As the silane coupling agent, a known organoalkoxysilane containing an organic reactive group can be used, and an organoalkoxysilane having an epoxy group is preferred, such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. The amount of the silane coupling agent used is preferably 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the alkoxide represented by formula (1).

[0130] Examples of organic solvents that can be used in preparing the gas barrier composition include methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, and n-butyl alcohol.

[0131] The sol-gel catalyst is preferably an acid or an amine compound. Examples of the acid include mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid; and organic acids such as acetic acid and tartaric acid. The amount of the acid used is preferably 0.001 mol or more and 0.05 mol or less per 1 mol of the total molar amount of the alkoxide represented by formula (1) and the silane coupling agent.

[0132] Examples of the amine compound include N,N-dimethylbenzylamine, tripropylamine, tributylamine, and tripentylamine. The amount of the amine compound used is preferably 0.01 to 1.0 parts by mass relative to 100 parts by mass of the total amount of the alkoxide represented by formula (1) and the silane coupling agent.

[0133] Examples of methods for applying the gas barrier composition include roll coating using a gravure roll coater or the like, spray coating, spin coating, dipping, brush coating, bar coating, and applicator coating.

[0134] Hereinafter, one embodiment of the method for forming the gas barrier coating layer will be described. A gas barrier composition is prepared by mixing an alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and, if necessary, a silane coupling agent. A polycondensation reaction gradually progresses within the composition. The composition is applied to a vapor-deposited film by a conventional method and dried. This drying further promotes polycondensation of the alkoxide and the water-soluble polymer (and the silane coupling agent, if the composition contains one) to form a composite polymer layer. Multiple composite polymer layers may be laminated by repeating the above procedure. The composition is heated at a temperature of preferably 20°C to 250°C, more preferably 50°C to 220°C, for example, 50°C to 120°C, for 1 second to 10 minutes. This allows the formation of a gas barrier coating layer.

[0135] The thickness of the gas barrier coating layer formed from the gas barrier composition using an alkoxide is preferably 0.01 μm to 100 μm, more preferably 0.1 μm to 50 μm, which can improve the gas barrier properties and prevent cracks from occurring in the vapor-deposited film, for example.

[0136] <Print layer> In one embodiment, the vapor-deposited film of the present disclosure may include a printed layer. The printed layer may be provided, for example, on the surface of the polyolefin resin layer opposite to the surface on the vapor-deposited film side. The printed layer may be provided, for example, on the surface of the vapor-deposited film opposite to the surface on the polyolefin resin layer side.

[0137] The printed layer includes, for example, an image. Examples of images include letters, figures, symbols, and combinations thereof. Examples of methods for forming the printed layer include gravure printing, offset printing, and flexographic printing. In one embodiment, flexographic printing is preferred from the viewpoint of reducing the environmental load. Furthermore, from the viewpoint of reducing the environmental load, the printed layer may be formed using ink derived from biomass.

[0138] [Laminate] A laminate according to the present disclosure includes the vapor-deposited film according to the present disclosure and a heat-seal layer made of polyolefin. In one embodiment, the laminate according to the present disclosure further includes a substrate made of polyolefin on the side of the vapor-deposited film facing the heat-seal layer or on the side opposite to the side facing the heat-seal layer. In one embodiment, the heat-seal layer is a surface layer on one side of the laminate.

[0139] In the present disclosure, the expression "AAA composed of polyolefin" means that the main component of the AAA is polyolefin, but is not limited to a configuration in which the AAA is composed solely of polyolefin. The AAA may contain components other than polyolefin. Specifically, the polyolefin content in the AAA is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more.

[0140] In the present disclosure, the expression "AAA composed of polyethylene" means that the main component of the AAA is polyethylene, but is not limited to a configuration in which the AAA is composed solely of polyethylene. The AAA may contain components other than polyethylene. Specifically, the polyethylene content in the AAA is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more.

[0141] For example, polyethylene includes high-density polyethylene and linear low-density polyethylene, which are classified as the same type of resin material, whereas polyethylene and polyester are not classified as the same type of resin material.

[0142] The polyolefin content, for example, the polyethylene content or the polypropylene content, in the entire laminate of the present disclosure is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more. Because such a laminate uses polyolefins such as polyethylene and polypropylene, which are the same type of resin material, it can be classified as a so-called monomaterial material and can be suitably used, for example, for producing monomaterial packaging containers.

[0143] Fig. 3 shows one embodiment of a laminate according to the present disclosure. The laminate 2 shown in Fig. 3 comprises, in this order in the thickness direction, a vapor-deposited film 1 (resin substrate 10 / vapor-deposited film 20), an adhesive layer 40, and a heat-seal layer 50 made of polyolefin. In this embodiment, the vapor-deposited film 1 may further comprise a printed layer (not shown). The printed layer may be provided, for example, on the polyolefin resin layer 12 of the vapor-deposited film 1. The printed layer may be provided, for example, on the vapor-deposited film 20 of the vapor-deposited film 1 (between the vapor-deposited film 20 and the adhesive layer 40), in which case the vapor-deposited film 20 is a transparent vapor-deposited film.

[0144] One embodiment of a laminate according to the present disclosure is shown in Fig. 4. The laminate 2 shown in Fig. 4 includes, in the thickness direction, a substrate 30 made of polyolefin, an adhesive layer 40, a vapor-deposited film 1 (vapor-deposited film 20 / resin substrate 10), the adhesive layer 40, and a heat-seal layer 50 made of polyolefin, in this order. The vapor-deposited film 20 of the vapor-deposited film 1 faces the substrate 30.

[0145] One embodiment of a laminate according to the present disclosure is shown in Fig. 5. The laminate 2 shown in Fig. 5 includes, in this order in the thickness direction, a vapor-deposited film 1 (resin substrate 10 / vapor-deposited film 20), an adhesive layer 40, a substrate 30 made of polyolefin, the adhesive layer 40, and a heat-seal layer 50 made of polyolefin. The vapor-deposited film 20 of the vapor-deposited film 1 faces the substrate 30.

[0146] 4 and 5, the laminate 2 may further include a printed layer (not shown) on the substrate 30. The printed layer is formed, for example, on the surface of the substrate 30 facing the deposited film 1.

[0147] <Heat seal layer> The laminate of the present disclosure comprises a heat seal layer.

[0148] The heat seal layer is made of polyolefin, a resin material that can be fused to each other by heat. Examples of polyolefin include polyethylene, polypropylene, polybutene, and polymethylpentene. Specific examples include ethylene-α-olefin copolymers such as very low-density polyethylene, low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, ethylene-(meth)acrylic acid copolymers, ethylene-methyl(meth)acrylate copolymers, and ethylene-ethyl(meth)acrylate copolymers.

[0149] In one embodiment, the resin material constituting the heat seal layer is a polyolefin, which is the same type of resin material as the resin material constituting the polyolefin resin layer in the vapor-deposited film. A laminate having such a configuration can be suitably used as a laminate for producing a mono-material packaging container. The heat seal layer may contain one or more polyolefins.

[0150] From the viewpoints of heat-sealability and recyclability, the heat-seal layer is preferably made of polyethylene or polypropylene, more preferably made of polyethylene, and examples of the polyethylene include ultra-low density polyethylene, low density polyethylene, and linear low density polyethylene. Details of polyolefins such as polyethylene and polypropylene are as explained in the section on the polyolefin resin layer, and will not be described here.

[0151] The content of polyethylene in the heat seal layer is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. Such a configuration can improve the recyclability of the laminate, for example.

[0152] From the viewpoint of heat sealing property, the heat seal layer is preferably an unstretched film. An unstretched film refers to a film that has not been subjected to a stretching treatment, such as an extrusion-molded film that has not been subjected to a stretching treatment. Details of the stretching treatment are as described above.

[0153] The heat seal layer may contain one or more of the above additives. The heat seal layer may have a single-layer structure or a multi-layer structure. In one embodiment, the number of layers of the heat seal layer is 2 to 7, for example, 3 to 7, or 3 to 5. In one embodiment, the number of layers of the heat seal layer is an odd number, for example, 3, 5, or 7.

[0154] The thickness of the heat seal layer is preferably 10 μm or more and 300 μm or less, more preferably 15 μm or more and 250 μm or less. From the viewpoint of strength and processability, the thickness of the heat seal layer is preferably changed appropriately depending on, for example, the mass of the contents to be contained in the packaging container.

[0155] <Base material> The substrate is made of a polyolefin. In one embodiment, the resin material constituting the substrate is a polyolefin, which is the same type of resin material as the resin material constituting the heat seal layer or the resin material constituting the polyolefin resin layer in the vapor-deposited film. A laminate having such a configuration can be suitably used as a laminate for producing a mono-material packaging container.

[0156] From the viewpoint of the recyclability of the packaging container, the substrate is preferably composed of polyethylene or polypropylene, more preferably polyethylene. Details of polyolefins such as polyethylene and polypropylene are as explained in the section on the polyolefin resin layer, and therefore will not be described here. The substrate made of polyethylene will be specifically described below.

[0157] Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and very low-density polyethylene. From the viewpoints of the strength and heat resistance of the substrate, high-density polyethylene and medium-density polyethylene are preferred, and from the viewpoint of stretchability, medium-density polyethylene is preferred.

[0158] The substrate may contain one or more polyethylenes. The content of polyethylene in the substrate is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. With such a configuration, for example, the recyclability of the laminate can be improved.

[0159] When the substrate has a multilayer structure, the polyethylene content in each layer constituting the substrate is independently preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. Such a configuration can, for example, improve the recyclability of the laminate.

[0160] The substrate may contain one or more resin materials other than polyethylene. Examples of such resin materials include polyolefins such as polypropylene, (meth)acrylic resins, vinyl resins, cellulose resins, polyamides, polyesters, and ionomer resins. From the viewpoint of recyclability, it is particularly preferable that the substrate does not contain any resin materials other than polyethylene. The substrate may contain one or more of the above additives.

[0161] The haze value of the substrate is preferably 25% or less, more preferably 15% or less, and even more preferably 10% or less. The smaller the haze value, the better, but in one embodiment, the lower limit may be 0.1% or 1%. The haze value of the substrate is measured in accordance with JIS K7136.

[0162] The thickness of the substrate is preferably 10 μm or more and 60 μm or less, more preferably 15 μm or more and 50 μm or less. When the thickness of the substrate is 10 μm or more, for example, the rigidity and strength of the laminate can be improved. When the thickness of the substrate is 60 μm or less, for example, the processability of the laminate can be improved.

[0163] The substrate may have a single-layer structure or a multi-layer structure. Hereinafter, a substrate having a multi-layer structure will also be referred to as a "multi-layer substrate." A multi-layer substrate is preferred from the viewpoint of improving its strength, heat resistance, and stretchability.

[0164] In the multilayer substrate, the density of the polyethylene constituting each layer may be the same or different. For example, the multilayer substrate may have a density gradient between the layers. By providing a density gradient in the multilayer substrate, for example, its strength, heat resistance, and stretchability can be improved.

[0165] In a multilayer substrate having a density gradient, the absolute value of the density difference between any two adjacent layers is preferably small. The absolute value of the density difference is preferably 0.040 g / cm 3 or less, more preferably 0.030 g / cm 3 or less, more preferably 0.020 g / cm 3 This configuration makes it possible to effectively prevent, for example, delamination at the interfaces between the layers.

[0166] In the present disclosure, the density of each layer may be measured in accordance with the above-mentioned JIS K7112, or may be calculated from the density of the components constituting the layer. For example, when one layer contains multiple components (n types; n is an integer of 2 or more) with different densities (e.g., polyethylene), the average density D calculated according to the following formula (f1) av may be the density of the layer.

[0167] D av = ΣW i ×D i …(f1) In formula (f1), Σ is W for i from 1 to n. i ×Di where n is an integer greater than or equal to 2, and W i denotes the mass fraction of the i-th component, and D i is the density of the i-th component (g / cm 3 ) is shown.

[0168] The substrate is preferably subjected to a stretching treatment, and hereinafter such a substrate is also referred to as a "stretched substrate." The substrate is more preferably a multilayer substrate that has been subjected to a stretching treatment. Hereinafter such a substrate is also referred to as a "stretched multilayer substrate." The stretching treatment can improve, for example, the heat resistance and strength of the substrate. Such a stretched substrate, particularly a stretched multilayer substrate, can satisfy the physical properties required, for example, as the outer layer of a packaging material.

[0169] The stretching may be uniaxial or biaxial. In one embodiment, the stretching ratio in the longitudinal direction (MD) of the stretched substrate is preferably 2 to 10 times, more preferably 3 to 7 times. In one embodiment, the stretching ratio in the transverse direction (TD) of the stretched substrate is preferably 2 to 10 times, more preferably 3 to 7 times.

[0170] A stretching ratio of 2 times or more can improve, for example, the rigidity, strength, and heat resistance of the substrate, improve the printability of the substrate, and improve the transparency of the substrate.A stretching ratio of 10 times or less can achieve good stretching without causing breakage of the film, for example.

[0171] In one embodiment, the stretched substrate is a uniaxially stretched film, more specifically, a uniaxially stretched film that has been stretched in the machine direction (MD).

[0172] The stretched multilayer substrate has a multilayer structure of two or more layers. In one embodiment, the number of layers in the stretched multilayer substrate is from 2 to 7, for example, from 3 to 7, or from 3 to 5. The number of layers in the stretched multilayer substrate is preferably an odd number, for example, 3, 5, or 7. The multilayer structure of the stretched multilayer substrate can improve the balance between rigidity, strength, heat resistance, printability, and stretchability of the substrate. Each layer of the stretched multilayer substrate is preferably composed of polyethylene.

[0173] The substrate, such as a stretched multilayer substrate, may be subjected to the above-mentioned surface treatment. This can, for example, improve the adhesion between the substrate and a layer laminated on the substrate. An anchor coating layer may be formed on the surface of the substrate, such as a stretched multilayer substrate, using a conventionally known anchor coating agent.

[0174] A stretched multilayer substrate can be produced by forming a laminate from multiple resin materials or resin compositions using, for example, an inflation method or a T-die method, and then stretching the resulting laminate. The stretching treatment can improve the transparency, rigidity, strength, and heat resistance of the substrate, making it suitable for use as, for example, a substrate for packaging materials.

[0175] In one embodiment, the stretched multilayer substrate is obtained by stretching a laminate (precursor) having a multilayer structure. Specifically, the resin materials constituting each layer are co-extruded into a tubular shape to form a film, thereby producing a laminate. Alternatively, the resin materials constituting each layer are co-extruded into a tubular shape, and then the opposing layers are pressure-bonded together using a rubber roll or the like to produce a laminate. By producing a laminate using such a method, the number of defective products can be significantly reduced, and production efficiency can be improved.

[0176] For example, when the stretched multi-layer substrate is made of polyethylene and is produced by the T-die method, the melt flow rate (MFR) of the polyethylene constituting each layer of the multi-layer substrate is preferably 3 g / 10 min or more and 20 g / 10 min or less, from the viewpoints of film-forming properties and processability of the multi-layer substrate.

[0177] For example, when the stretched multi-layer substrate is made of polyethylene and is produced by an inflation method, the MFR of the polyethylene constituting each layer of the multi-layer substrate is preferably 0.5 g / 10 min or more and 5 g / 10 min or less, from the viewpoints of film-forming properties and processability of the multi-layer substrate.

[0178] The stretched multilayer substrate can be obtained, for example, by stretching the above-mentioned laminate. The preferred stretching ratio is as described above. Note that the laminate can also be stretched in an inflation film-forming machine. This allows the production of a stretched multilayer substrate, thereby further improving production efficiency.

[0179] Hereinafter, several examples of embodiments of the stretched multilayer base material will be described. Hereinafter, a layer having a polyethylene content of 80% by mass or more will be referred to as a "polyethylene layer." For example, a layer having a high-density polyethylene content of 80% by mass or more will be referred to as a "high-density polyethylene layer."

[0180] The stretched multilayer substrate of the first embodiment includes, in the thickness direction, a medium-density polyethylene layer, a high-density polyethylene layer, a blend layer of medium-density polyethylene and high-density polyethylene, a high-density polyethylene layer, and a medium-density polyethylene layer, in this order. This configuration can improve, for example, the printability, strength, and heat resistance of the substrate, and the stretchability of the pre-stretched laminate.

[0181] In the blend layer of medium-density polyethylene and high-density polyethylene, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0182] The stretched multilayer substrate of the second embodiment includes, in the thickness direction, a medium-density polyethylene layer, a medium-density polyethylene layer, a blend layer of medium-density polyethylene and linear low-density polyethylene, a medium-density polyethylene layer, and another medium-density polyethylene layer, in this order. This configuration can improve, for example, the printability, strength, and heat resistance of the substrate, and the stretchability of the pre-stretched laminate.

[0183] In the blend layer of medium-density polyethylene and linear low-density polyethylene, the mass ratio of medium-density polyethylene to linear low-density polyethylene (medium-density polyethylene / linear low-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0184] The stretched multilayer substrate of the third embodiment includes, in the thickness direction, a blend layer of medium-density polyethylene and high-density polyethylene, a blend layer of medium-density polyethylene and linear low-density polyethylene, a linear low-density polyethylene layer, a blend layer of medium-density polyethylene and linear low-density polyethylene, and a blend layer of medium-density polyethylene and high-density polyethylene. This configuration can improve, for example, the printability, strength, and heat resistance of the substrate, and the stretchability of the pre-stretched laminate.

[0185] In the blend layers of medium-density polyethylene and high-density polyethylene, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0186] In the blend layer of medium-density polyethylene and linear low-density polyethylene, the mass ratio of medium-density polyethylene to linear low-density polyethylene (medium-density polyethylene / linear low-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0187] The stretched multilayer substrate of the fourth embodiment includes, in the thickness direction, a blend layer of high-density polyethylene and medium-density polyethylene, a medium-density polyethylene layer, a blend layer of linear low-density polyethylene and medium-density polyethylene, a medium-density polyethylene layer, and a blend layer of high-density polyethylene and medium-density polyethylene. This configuration can improve, for example, the printability, strength, and heat resistance of the substrate, and the stretchability of the pre-stretched laminate.

[0188] In the blend layers of high-density polyethylene and medium-density polyethylene, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0189] In the blend layer of linear low-density polyethylene and medium-density polyethylene, the mass ratio of linear low-density polyethylene to medium-density polyethylene (linear low-density polyethylene / medium-density polyethylene) is preferably 0.25 or more and 4 or less, more preferably 0.4 or more and 2.4 or less.

[0190] In the stretched multilayer substrates of the first to fourth embodiments, the thickness of each of the two surface resin layers is preferably from 0.5 μm to 10 μm, more preferably from 1 μm to 8 μm, and even more preferably from 1 μm to 5 μm, which can further improve, for example, the heat resistance and printability of the substrate.

[0191] In the stretched multilayer substrates of the first to fourth embodiments, the thickness of each of the two surface resin layers is preferably smaller than the total thickness of the three inner layers (the multilayer intermediate layer). The ratio of the thickness of each of the two surface resin layers to the total thickness of the multilayer intermediate layer (surface resin layer / multilayer intermediate layer) is preferably 0.05 to 0.8, more preferably 0.1 to 0.7, and even more preferably 0.1 to 0.4. This can further improve, for example, the rigidity, strength, and heat resistance of the substrate.

[0192] The stretched multilayer substrate of the fifth embodiment comprises a high-density polyethylene layer and a medium-density polyethylene layer in this order in the thickness direction. The surface resin layer of the substrate is a high-density polyethylene layer, which can improve, for example, the strength and heat resistance of the substrate. The substrate comprises a medium-density polyethylene layer, which can improve, for example, the stretchability of the pre-stretched laminate.

[0193] The stretched multilayer substrate of the sixth embodiment includes a high-density polyethylene layer, a medium-density polyethylene layer, and a high-density polyethylene layer in this order in the thickness direction. This configuration can improve the strength and heat resistance of the substrate, suppress curling in the substrate, and improve the stretchability of the pre-stretched laminate, for example.

[0194] In the stretched multilayer base materials of the fifth and sixth embodiments, the thickness of the high-density polyethylene layer is preferably equal to or less than the thickness of the medium-density polyethylene layer, and the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer is preferably 0.1 or more and 1 or less, more preferably 0.2 or more and 0.5 or less.

[0195] The stretched multilayer substrate of the seventh embodiment comprises, in this order in the thickness direction, a high-density polyethylene layer, a medium-density polyethylene layer, a low-density polyethylene layer, a linear low-density polyethylene layer or an ultra-low-density polyethylene layer (for simplicity, these three layers are collectively referred to as the "low-density polyethylene layer, etc."), a medium-density polyethylene layer, and a high-density polyethylene layer. This configuration can, for example, improve the stretchability of the laminate before stretching, improve the strength and heat resistance of the substrate, and suppress curling in the substrate.

[0196] In the stretched multilayer substrate of the seventh embodiment, the thickness of the high-density polyethylene layer is preferably equal to or less than the thickness of the medium-density polyethylene layer, and the ratio of the thickness of the high-density polyethylene layer to the thickness of the medium-density polyethylene layer is preferably 0.1 or more and 1 or less, more preferably 0.2 or more and 0.5 or less.

[0197] In the stretched multilayer substrate of the seventh embodiment, the thickness of the high-density polyethylene layer is preferably equal to or greater than the thickness of the low-density polyethylene layer, etc. The ratio of the thickness of the high-density polyethylene layer to the thickness of the low-density polyethylene layer, etc. is preferably 1 or more and 4 or less, more preferably 1 or more and 2 or less.

[0198] Other embodiments of the stretched multilayer substrate include a substrate comprising, in this order in the thickness direction, a high-density polyethylene layer, a high-density polyethylene layer, a blend layer of medium-density polyethylene and high-density polyethylene, a high-density polyethylene layer, and a high-density polyethylene; and a substrate comprising, in this order in the thickness direction, a medium-density polyethylene layer, a high-density polyethylene layer, a linear low-density polyethylene layer, a high-density polyethylene layer, and a medium-density polyethylene layer.

[0199] Further, a substrate may be provided with, in the thickness direction, a high-density polyethylene layer, a blend layer of high-density polyethylene and medium-density polyethylene, a low-density polyethylene layer or the like, a blend layer of high-density polyethylene and medium-density polyethylene, and a high-density polyethylene layer in this order.

[0200] <Print layer> In one embodiment, the laminate of the present disclosure further includes a printed layer formed on the above-described substrate. In one embodiment, the laminate of the present disclosure preferably includes a printed layer on the surface of the substrate facing the heat seal layer, because this can suppress deterioration of the image over time.

[0201] The printed layer includes, for example, an image. Examples of images include letters, figures, symbols, and combinations thereof. Examples of methods for forming the printed layer include gravure printing, offset printing, and flexographic printing. In one embodiment, flexographic printing is preferred from the viewpoint of reducing the environmental load. Furthermore, from the viewpoint of reducing the environmental load, the printed layer may be formed on the surface of the substrate using a biomass-derived ink.

[0202] <Adhesive layer> In one embodiment, the laminate of the present disclosure includes an adhesive layer between any layers, such as between the substrate and the vapor-deposited film, or between the substrate or the vapor-deposited film and the heat-sealing layer, thereby improving the adhesion between the substrate and the vapor-deposited film and between other layers.

[0203] The adhesive layer contains one or more types of adhesives, such as one-component curing adhesives, two-component curing adhesives, and non-curing adhesives.

[0204] The adhesive may be a solvent-free adhesive or a solvent-based adhesive, and examples of the adhesive include polyether adhesives, polyester adhesives, silicone adhesives, epoxy adhesives, urethane adhesives, rubber adhesives, vinyl adhesives, phenol adhesives, and olefin adhesives. The adhesive layer may contain one or more of the above additives.

[0205] The thickness of the adhesive layer is preferably 0.5 μm to 10 μm, more preferably 0.8 μm to 8 μm, and even more preferably 1 μm to 6 μm. When the thickness of the adhesive layer is equal to or greater than the lower limit, for example, the adhesion between layers can be improved. When the thickness of the adhesive layer is equal to or less than the upper limit, for example, the recyclability of the packaging container can be improved.

[0206] The adhesive layer can be formed by applying an adhesive to the target by a method such as direct gravure roll coating, gravure roll coating, kiss coating, reverse roll coating, Fontaine method, or transfer roll coating, and drying as necessary.

[0207] [Application] The vapor-deposited film or laminate of the present disclosure can be suitably used for packaging material applications. The packaging material is used to produce a packaging container. The packaging material comprises the laminate of the present disclosure. The packaging container can be produced by using at least a packaging material comprising the laminate of the present disclosure.

[0208] A packaging container includes the vapor-deposited film or laminate of the present disclosure. Examples of packaging containers include packaging bags, tube containers, and lidded containers. The lidded container includes a container body having a storage section and a lid joined (heat sealed) to the container body so as to seal the storage section.

[0209] Examples of heat sealing methods include bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, and ultrasonic sealing.

[0210] Examples of packaging bags include various types of packaging bags 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 palm seal type (pillow seal type), a pleated seal type, a flat bottom seal type, a square bottom seal type, and a gusset type.

[0211] 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.

[0212] In one embodiment, a packaging bag can be produced by folding the laminate of the present disclosure in half and overlapping them so that the heat seal layer is located on the inside, and then heat-sealing the edges, etc. In another embodiment, a packaging bag can be produced by overlapping multiple laminates of the present disclosure so that the heat seal layers face each other, and then heat-sealing the edges, etc. The entire packaging bag may be made of the above-mentioned laminate, or only a portion of the packaging bag may be made of the above-mentioned laminate.

[0213] In one embodiment, the laminate of the present disclosure is used as a lid material for a lidded container.

[0214] The contents to be contained in the packaging container may be, for example, liquids, solids, powders, and gels. The contents may be food or beverages, or non-food or beverages such as chemicals, cosmetics, and pharmaceuticals. The contents may be frozen foods or retort foods. After the contents are contained in the packaging container, the packaging container can be hermetically sealed by heat-sealing the opening of the packaging container.

[0215] The present disclosure relates to, for example, the following [1] to

[15] . [1] A vapor-deposited film comprising a resin substrate and a vapor-deposited film, wherein the resin substrate comprises a polyolefin resin layer and a polyamide resin layer, the vapor-deposited film is provided on the polyamide resin layer, and the polyamide resin layer contains an aliphatic polyamide and a semi-aromatic polyamide. [2] The vapor-deposited film according to the above [1], wherein the polyolefin resin layer is a polyethylene resin layer or a polypropylene resin layer. [3] The vapor-deposited film according to [1] or [2] above, wherein the content of the aliphatic polyamide in the polyamide resin layer is more than 50% by mass and not more than 99% by mass. [4] The vapor-deposited film according to any one of the above [1] to [3], wherein the content of the semi-aromatic polyamide in the polyamide resin layer is 1 part by mass or more and 100 parts by mass or less per 100 parts by mass of the aliphatic polyamide. [5] The vapor-deposited film according to any one of the above [1] to [4], wherein the aliphatic polyamide is a crystalline aliphatic polyamide having a melting point of 170°C or higher and 230°C or lower. [6] The vapor-deposited film according to [5] above, wherein the polyolefin resin layer is a polyethylene resin layer containing polyethylene, and the difference (Tm1 - Tm2) between the melting point (Tm1) of the crystalline aliphatic polyamide contained in the polyamide resin layer and the melting point (Tm2) of the polyethylene contained in the polyethylene resin layer is 90°C or less. [7] The vapor-deposited film according to any one of the above [1] to [6], wherein the resin substrate further comprises an adhesive resin layer between the polyolefin resin layer and the polyamide resin layer. [8] The vapor-deposited film according to any one of the above [1] to [7], wherein the resin substrate is a co-extruded resin film, and the vapor-deposited film is provided on a polyamide resin layer of the co-extruded resin film. [9] The vapor-deposited film according to any one of the above [1] to [8], wherein the resin substrate is a stretched film, and the vapor-deposited film is provided on a polyamide resin layer of the stretched film.

[10] A laminate comprising the vapor-deposited film according to any one of the above [1] to [9] and a heat-sealable layer made of polyolefin.

[11] The laminate according to the above

[10] , further comprising a substrate made of polyolefin on the surface of the vapor-deposited film on the side of the heat seal layer or on the surface opposite to the side of the heat seal layer.

[12] The laminate according to the above

[11] , wherein the polyolefin constituting the heat seal layer is polyethylene or polypropylene, and the polyolefin constituting the substrate is polyethylene or polypropylene.

[13] The laminate according to

[11] or

[12] above, further comprising a printed layer on a substrate made of polyolefin.

[14] A packaging material comprising the laminate according to any one of

[10] to

[13] above.

[15] A packaging container comprising the vapor-deposited film according to any one of the above [1] to [9] or the laminate according to any one of the above

[10] to

[13] . [Example]

[0216] The vapor-deposited film of the present disclosure will be described in more detail based on examples, but the vapor-deposited film of the present disclosure is not limited to these examples. Hereinafter, "parts by mass" will be simply referred to as "parts".

[0217] [Resin material] The following resin materials were used: Polyethylene A: ELITE5538G, manufactured by Dow Chemical Co. Medium density polyethylene (MDPE), density: 0.941 g / cm 3 , Melting point: 129°C, MFR: 1.3g / 10min Nylon 6 / 66A: Ube Industries, 5033B Density: 1.14g / cm 3 , Melting point: 196℃, Viscosity number: 249, relative viscosity: 4.05 Nylon 6 / 66B: BASF Ultramid C40LN Density: 1.12g / cm 3 , Melting point: 189℃, Viscosity number: 250, relative viscosity: 4.0 Nylon 6 / 66C: BASF Ultramid C33 Density: 1.12g / cm 3 , Melting point: 196℃, Viscosity number: 195, relative viscosity: 3.3 Barrier modifier A: EMS Grivory G21, an amorphous semi-aromatic polyamide, Density: 1.18g / cm 3 , Glass transition temperature: 125℃, MVR:20cm 3 / 10 minutes ·Adhesive resin A: Manufactured by Mitsui Chemicals, ADMER AT1955E, Density: 0.89g / cm 3 , MFR: 2.6g / 10min

[0218] [Example 1] A five-layer coextrusion film was produced by inflation molding using a mixture of 80 parts nylon 6 / 66A and 20 parts barrier modifier A, adhesive resin A, polyethylene A, polyethylene A, and polyethylene A. The film consisted of a 10 μm-thick polyamide resin layer (first resin layer, PA resin layer), a 10 μm-thick adhesive resin layer (second resin layer), and three 80 μm-thick polyethylene resin layers (third to fifth resin layers, PE resin layers). The film was stretched four times in the longitudinal direction (MD) to obtain a 25 μm-thick stretched film. The stretched film consisted of a 2.5 μm-thick polyamide resin layer, a 2.5 μm-thick adhesive resin layer, and three 20 μm-thick polyethylene resin layers.

[0219] A 30 nm thick Al vapor-deposited film was formed on the surface of the polyamide resin layer of the stretched film by the PVD method to obtain a vapor-deposited film. The optical density (OD value) of the vapor-deposited film was measured and found to be 3.0.

[0220] [Examples 2 to 3 and Reference Examples 1 to 3] A film, a stretched film, and a vapor-deposited film were obtained in the same manner as in Example 1, except that the compounding composition of the polyamide resin layer, the thickness of each layer, and the stretching ratio were changed as shown in Table 1.

[0221] [Comparative Example 1] Polyethylene A was used to form a five-layer co-extrusion film by inflation molding, resulting in a 125 μm thick film consisting of five polyethylene resin layers (first to fifth resin layers). The film was stretched five times in the machine direction (MD) to obtain a stretched film with a thickness of 25 μm.

[0222] A 30 nm thick Al vapor-deposited film was formed on the polyethylene resin layer of the stretched film by PVD, to obtain a vapor-deposited film. The optical density (OD value) of the vapor-deposited film was measured and found to be 3.0.

[0223] [Evaluation method] <Optical density> The optical density (OD value) of the vapor-deposited film was determined as follows. Using a haze meter HM-150 (Murakami Color Research Laboratory), the total luminous transmittance (Tt) was determined with an entrance opening of φ20 mm and a light beam of φ14 mm. The total luminous transmittance conforms to JIS K7361. The calculated total luminous transmittance was substituted into the following equation to calculate the optical density. The measurement results are shown in Table 1. Optical density (OD value) = -log 10 (Total light transmittance / 100)

[0224] <Transparency> The haze (H) of the stretched film was measured using a haze meter HM-150 (Murakami Color Research Laboratory) with an inlet opening of φ20 mm and a light beam of φ14 mm. The haze was measured in accordance with JIS K7136. The measurement results are shown in Table 1.

[0225] <Surface roughness (Ra)> The arithmetic mean surface roughness (Ra) of the polyamide resin layer (polyethylene resin layer in Comparative Example 1) in the stretched film was measured in an area of ​​15 μm × 15 μm using an atomic force microscope (manufactured by Bruker). The measurement results are shown in Table 1.

[0226] <Evaluation of curling of stretched film> The stretched film was cut into a 10 cm square with the curled side facing up. The stretched film was then cut along two diagonals so that 2 cm remained at each of the four corners (see Figure 6). The resulting test piece was used to evaluate curl at four measurement positions. The evaluation criteria were as follows. The evaluation results are shown in Table 1.

[0227] (Evaluation criteria) AA: I don't have any curls at all. BB: The tip of the diagonally cut stretched film is slightly warped. CC: The tip of the diagonally cut stretched film is curled. DD: It's curly.

[0228] <Gas barrier property evaluation> The oxygen permeability (cc / m) of the vapor-deposited films obtained in the Examples, Reference Examples, and Comparative Examples 2 ·day·atm) and water vapor permeability (g / m 2 ·day) was measured by the following method. The measurement results are shown in Table 1.

[0229] Using an oxygen permeability measuring device (OX-TRAN2 / 20 manufactured by MOCON), the vapor-deposited film was set so that the fifth resin layer surface faced the oxygen supply side, and the oxygen permeability was measured in an environment of 23°C and a relative humidity of 65% RH in accordance with JIS K7126.

[0230] Using a water vapor permeability measuring device (MOCON, PERMATRAN-w 3 / 33), the vapor deposition film was set so that the fifth resin layer surface faced the water vapor supply side, and the water vapor permeability was measured in accordance with JIS K7129 under an environment of 40°C and a relative humidity of 90%RH.

[0231] <Appearance quality characteristics> A transparent adhesive sheet (LUCIACS CS9862UAS, manufactured by Nitto Denko Corporation) was used. The transparent adhesive sheet had a first main surface and a second main surface. The fifth resin layer surface of the vapor-deposited film was bonded to the first main surface of the transparent adhesive sheet, and the second main surface of the transparent adhesive sheet was bonded to a glass plate (Cut Glass Eagle XG, manufactured by Tokyo Special Glass Co., Ltd.). In this way, a test specimen was obtained. Black paper was placed under the glass plate of the test specimen. The stretched film of the vapor-deposited film was set so that the stretching direction of the stretched film was parallel to the light source direction of the glossmeter (Rhopoint IQ-S, manufactured by Konica Minolta). The vapor-deposited film was measured for 20° gloss (based on JIS Z8741), reflective haze (based on ASTM E430), image clarity (based on ASTM D5767), and specular reflection peak value (Rspec). The measurement results are shown in Table 1.

[0232] [Table 1] [Explanation of symbols]

[0233] 1: Vapor-deposited film 2: Laminate 10: Resin substrate 12: Polyolefin resin layer 13: Adhesive resin layer 14: Polyamide resin layer 20: Vapor deposition film 30: Base material 40: Adhesive layer 50: Heat seal layer

Claims

1. A vapor-deposited film used in a laminate for packaging materials, comprising at least a vapor-deposited film and a heat-seal layer made of polyolefin, The aforementioned vapor-deposited film comprises a resin substrate and a vapor-deposited film. The resin substrate comprises a polyolefin resin layer and a polyamide resin layer. The vapor-deposited film is provided on the polyamide resin layer, The polyamide resin layer contains an aliphatic polyamide and a semi-aromatic polyamide. Metallized film.

2. The vapor-deposited film according to claim 1, wherein the polyolefin resin layer is a polyethylene resin layer or a polypropylene resin layer.

3. The vapor-deposited film according to claim 1 or 2, wherein the content of the aliphatic polyamide in the polyamide resin layer is more than 50% by mass and 99% by mass or less.

4. The vapor-deposited film according to any one of claims 1 to 3, wherein the content of the semi-aromatic polyamide in the polyamide resin layer is 1 part by mass or more and 100 parts by mass or less per 100 parts by mass of the aliphatic polyamide.

5. The vapor-deposited film according to any one of claims 1 to 4, wherein the aliphatic polyamide is a crystalline aliphatic polyamide having a melting point of 170°C or higher and 230°C or lower.

6. The polyolefin resin layer is a polyethylene resin layer containing polyethylene. The vapor-deposited film according to claim 5, wherein the difference (Tm1 - Tm2) between the melting point (Tm1) of the crystalline aliphatic polyamide contained in the polyamide resin layer and the melting point (Tm2) of the polyethylene contained in the polyethylene resin layer is 90°C or less.

7. The vapor-deposited film according to any one of claims 1 to 6, wherein the resin substrate further comprises an adhesive resin layer between the polyolefin resin layer and the polyamide resin layer.

8. The vapor-deposited film according to any one of claims 1 to 7, wherein the resin substrate is a co-extruded resin film, and the vapor-deposited film is provided on the polyamide resin layer of the co-extruded resin film.

9. The vapor-deposited film according to any one of claims 1 to 8, wherein the resin substrate is a stretched film, and the vapor-deposited film is provided on the polyamide resin layer of the stretched film.

10. A vapor-deposited film according to any one of claims 1 to 9, A heat-seal layer made of polyolefin and A laminate comprising the above.

11. The laminate according to claim 10, further comprising a substrate made of polyolefin on the heat-sealing layer side of the vapor-deposited film, or on the side opposite to the heat-sealing layer side.

12. The laminate according to claim 11, wherein the polyolefin constituting the heat seal layer is polyethylene or polypropylene, and the polyolefin constituting the base material is polyethylene or polypropylene.

13. The laminate according to claim 11 or 12, further comprising a printed layer on the substrate made of polyolefin.

14. A packaging material comprising a laminate according to any one of claims 10 to 13.

15. A vapor-deposited film according to any one of claims 1 to 9, or Laminate according to any one of claims 10 to 13 A packaging container equipped with the following features.

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