Gas barrier film and package

Abstract

Provided are: a gas barrier film in which a vapor-deposited layer (A) of aluminum oxide and / or silicon oxide and a vapor-deposited layer (B) of divalent metal oxide (B) are laminated in this order on a plastic film; and a package containing the gas barrier film. The divalent metal oxide (B) is preferably a zinc oxide, a magnesium oxide, and / or a calcium oxide. The thickness of the vapor-deposited layer (B) preferably falls within a range of 1-200 nm. The ratio of the fluorescent X-ray intensity of the metal of the vapor-evaporated layer (B) to the fluorescent X-ray intensity of the metal of the vapor-evaporated layer (A) preferably falls within a range of 0.5:100 to 90:100.

Description

Gas barrier film and packaging

[0001] The present invention relates to a gas barrier film having excellent flexibility.

[0002] Packaging materials used for packaging foods, pharmaceuticals, etc. are required to have barrier properties against oxygen and water vapor (hereinafter referred to as gas barrier properties) in order to prevent the contents, flavor, and efficacy from being altered or reduced due to oxidation. Resin films having vapor-deposited films are used because they can provide high barrier performance at low cost. Examples of gas barrier films having vapor-deposited films include a film in which aluminum oxide (AlOx) and / or silicon oxide (SiOx) is vapor-deposited on a polyethylene terephthalate film, or a film in which multiple vapor-deposited silicon oxide films are laminated (see, for example, Patent Document 1), and a gas barrier laminate film in which a vapor-deposited material containing metallic silicon and silicon oxide, and a vapor-deposited material containing a metal or metal oxide selected from aluminum, zinc, tin, and iron are vapor-deposited on a resin substrate having an anchor coat layer (see, for example, Patent Document 2).

[0003] However, metal oxide vapor-deposited films are generally weak against bending, such as twisting and folding, and cracks can easily occur in parts of the vapor-deposited film when laminating it with other films or when bending it during bag making after lamination, resulting in a decrease in barrier performance.

[0004] JP 2013-253319 A JP 2014-069389 A

[0005] An object of the present invention is to provide a gas barrier film that is free from cracks in parts of the vapor-deposited film, has excellent flexibility, and has good gas barrier properties.

[0006] That is, the present invention provides a gas barrier film in which a vapor-deposited layer (A) of aluminum oxide and / or silicon oxide and a vapor-deposited layer (B) of a divalent metal oxide (B) are laminated in this order on a plastic film.

[0007] The present invention also provides a package containing the gas barrier film described above.

[0008] According to the present invention, it is possible to provide a gas barrier film having excellent flexibility and good gas barrier properties without cracking in parts of the vapor-deposited film, and a package using the same.

[0009] (Definition of Terms) In this specification, "~" means greater than or equal to the value before "~" and less than or equal to the value after "~".

[0010] (Gas Barrier Film) The gas barrier film of the present invention is characterized in that a vapor-deposited layer (A) of aluminum oxide and / or silicon oxide and a vapor-deposited layer (B) of a divalent metal oxide (B) are laminated in this order on a plastic film.

[0011] (Plastic Film) The material of the plastic film used in the present invention is not particularly limited, and it is possible to use plastic films that are used as packaging materials for packaging foods, medicines, etc. Specific examples include polyethylene terephthalate (PET) film, polystyrene film, polyamide film, nylon film, polyacrylonitrile film, polyolefin films such as polyethylene film (OPE: biaxially oriented polyethylene film, LLDPE: low-density polyethylene film, HDPE: high-density polyethylene film) and polypropylene film (CPP: non-oriented polypropylene film, OPP: biaxially oriented polypropylene film), polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, cellophane, etc.

[0012] When mono-material packaging is considered, a film made of a thermoplastic resin containing an olefin resin as a main component can be used as the substrate. Specific examples of olefin resins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene, polypropylene, ethylene-propylene copolymers, α-olefin polymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, ethylene-acrylic acid copolymers, ethylene-methyl methacrylate copolymers, ethylene-ethyl acrylate copolymers, cyclic olefin resins, ionomer resins, and polymethylpentene; and modified olefin resins obtained by modifying olefin resins with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, or other unsaturated carboxylic acids.

[0013] It is also preferable to use a film made of a material containing biomass-derived components as the film substrate. Biomass films are commercially available from various companies, and for example, sheets such as those listed in the list of biomass-certified products listed by the Japan Organics Recycling Association can be used.

[0014] Specifically, well-known films are made from biomass-derived ethylene glycol. Biomass-derived ethylene glycol is made from ethanol (biomass ethanol) produced from biomass as a raw material. For example, biomass-derived ethylene glycol can be obtained by converting biomass ethanol into ethylene oxide by a conventionally known method to produce ethylene glycol. Alternatively, commercially available biomass ethylene glycol may be used; for example, biomass ethylene glycol commercially available from India Glycoal Limited can be suitably used.

[0015] Alternatively, products using biomass raw materials classified by the biomass plastic content specified in ISO 16620 or ASTM D6866 are also on the market. Radioactive carbon-14C exists in the atmosphere at a rate of 1 in 1012 particles, and this rate is the same for atmospheric carbon dioxide, so this rate remains the same even in plants that fix this carbon dioxide through photosynthesis. Therefore, the carbon in plant-derived resins contains radioactive carbon-14C. In contrast, the carbon in fossil fuel-derived resins contains almost no radioactive carbon-14C. Therefore, by measuring the concentration of radioactive carbon-14C in the resin using an accelerator mass spectrometer, the plant-derived resin content in the resin, i.e., the biomass plastic content, can be determined. Examples of plant-derived low-density polyethylene, which is a biomass plastic having a biomass plastic content of 80% or more, preferably 90% or more as specified by ISO 16620 or ASTM D6866, include products manufactured by Braskem under the trade names "SBC818," "SPB608," "SBF0323HC," "STN7006," "SEB853," and "SPB681," and films using these as raw materials can be suitably used.

[0016] For example, biomass polyolefin films, such as biomass polyethylene films and biomass polyethylene-polypropylene films, containing polyethylene resins made from biomass-derived ethylene glycol are known as alternatives to conventional polyolefin films made from petroleum-based raw materials. The polyethylene resin is not particularly limited except that biomass-derived ethylene glycol is used as part of the raw material. Examples of the polyethylene resin include ethylene homopolymers and copolymers of ethylene and α-olefins containing ethylene as the main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units). These can be used alone or in combination of two or more. The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples include α-olefins having 4 to 8 carbon atoms, such as 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Known polyethylene resins, such as low-density polyethylene resins, medium-density polyethylene resins, and linear low-density polyethylene resins, can be used. Among these, from the viewpoint of making it even more difficult for damage such as holes or tears to occur even when films rub against each other, linear low-density polyethylene resin (LLDPE) (a copolymer of ethylene and 1-hexene or a copolymer of ethylene and 1-octene) is preferred, and linear low-density polyethylene resin having a density of 0.910 to 0.925 g / cm is more preferred.

[0017] The biomass film may be a laminate of multiple biomass films, or may be a laminate of a conventional petroleum-based film and a biomass film.

[0018] The substrate may be one that has been subjected to some kind of surface treatment, such as a physical treatment such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, or flame treatment, or a chemical treatment such as oxidation treatment using chemicals, in order to enhance the adhesion of the vapor-deposited layer (A) described below. Alternatively, the substrate may have a coating layer that enhances adhesion, such as an anchor coating agent.

[0019] The substrate can be produced from the above-mentioned resin by a conventionally known film-forming method such as extrusion, cast molding, T-die molding, cutting, inflation, etc. The substrate may be an unstretched film, or may be one that has been stretched uniaxially or biaxially using a tenter system, a tubular system, or the like, from the viewpoint of the strength, dimensional stability, and heat resistance of the film (1).

[0020] The substrate may contain additives as needed. Specifically, plastic compounding agents and additives such as elastomers, lubricants, crosslinking agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, and pigments may be added for the purpose of improving or modifying processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, mold releasability, flame retardancy, mildew resistance, electrical properties, strength, etc. The amount of additive added is adjusted within a range that does not affect other performance properties or recyclability.

[0021] The thickness of the substrate is not particularly limited and may be appropriately selected from the range of 0.1 to 300 μm in terms of moldability and transparency. It is preferably in the range of 0.3 to 100 μm. If the thickness is less than 0.1 μm, the strength may be insufficient, and if it exceeds 300 μm, the rigidity may be too high, making processing difficult.

[0022] From the viewpoint of recycling, it is preferable that the layer structure is as simple as possible, but from the viewpoint of distribution of the packaging material, printing is often required to indicate the contents of the packaging material or a description or name of the product. Printing is often also performed on the substrate.

[0023] (Printed Layer) The printed layer is a layer on which characters, figures, symbols, and other desired designs are printed. The printing method and printing ink are not particularly limited, and known printing methods and printing inks can be used. Printing inks using methods such as gravure printing, flexographic printing, lithographic offset printing, and inkjet recording printing are often used for the film used as the substrate. Printing inks that combine these printing methods with methods of curing using active energy rays such as ultraviolet (UV), LED, and electron beam (EB), or methods of curing using heat, are also used. Depending on the solvent used, inks may be referred to as aqueous inks or organic solvent-based inks.

[0024] Specific examples include gravure printing ink and flexographic printing ink (in some industries, gravure printing ink and flexographic printing ink are sometimes referred to as liquid ink), ultraviolet-curable ink for lithographic offset printing, electron-beam-curable ink for lithographic offset printing, ultraviolet-curable ink for inkjet recording and printing, and electron-beam-curable ink for inkjet recording and printing.

[0025] The position where the printed layer printed using these inks is provided is arbitrary, and it may be provided on the first substrate, or a substrate on which a separate printed layer is provided may be one of the constituent components of the laminate of the present invention, and the position is arbitrary. Furthermore, the ink may contain a resin, a colorant, and a solvent as essential components, or it may be a so-called clear ink that contains a resin and a solvent but does not substantially contain a colorant. Below, we will explain the liquid inks that are most commonly used for printing on films.

[0026] The resin used in the liquid ink is not particularly limited and may include, for example, acrylic resin, polyester resin, styrene resin, styrene-maleic acid resin, maleic acid resin, polyamide resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-acrylic copolymer resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, polyvinyl chloride resin, chlorinated polypropylene resin, cellulose-based resin, epoxy resin, alkyd resin, rosin-based resin, rosin-modified maleic acid resin, ketone resin, cyclized rubber, chlorinated rubber, butyral, petroleum resin, etc., and one or more of these may be used in combination. Preferably, at least one or two or more selected from polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, and cellulose-based resin are used.

[0027] Colorants used in liquid inks include inorganic pigments such as titanium oxide, red iron oxide, antimony red, cadmium red, cadmium yellow, cobalt blue, Prussian blue, ultramarine, carbon black, and graphite; organic pigments such as soluble azo pigments, insoluble azo pigments, azo lake pigments, condensed azo pigments, copper phthalocyanine pigments, and condensed polycyclic pigments; and extender pigments such as calcium carbonate, kaolin clay, barium sulfate, aluminum hydroxide, and talc.

[0028] Liquid inks for film printing are often organic solvent-based inks. The organic solvent used preferably does not contain an aromatic hydrocarbon organic solvent. More specific examples include alcohol-based organic solvents such as methanol, ethanol, n-propanol, isopropanol, and butanol; ketone-based organic solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ester-based organic solvents such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate; aliphatic hydrocarbon-based organic solvents such as n-hexane, n-heptane, and n-octane; and alicyclic hydrocarbon-based organic solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, cycloheptane, and cyclooctane. These may be used alone or in combination of two or more.

[0029] (Aluminum oxide and / or silicon oxide vapor deposition layer (A)) The gas barrier film of the present invention has a vapor deposition layer of aluminum oxide (also called aluminum oxide, alumina, or AlOx, and examples thereof include AlO and Al ２ O ３ and / or silicon oxide (sometimes called silicon oxide, silica, or SiOx, and is not limited to SiO or SiO ２ The silicon dioxide film has a vapor-deposited layer (A) of silicon dioxide, which is a silicon oxide such as silicon dioxide or a mixture thereof.

[0030] The vapor-deposited layer (A) is preferably formed by a vapor-phase thin-film formation method. Vapor-phase thin-film formation methods used to form the vapor-deposited layer (A) in the present invention include physical deposition methods (hereinafter referred to as PVD methods) such as vacuum deposition, sputtering, and ion plating, and chemical deposition methods (hereinafter referred to as CVD methods). Any method may be used as long as the effects of the present invention can be obtained. As described above, the vapor-phase thin-film formation method used in the present invention is not particularly limited, but PVD methods such as vacuum deposition, sputtering, and ion plating are preferred because they allow for the easy formation of stable thin films, and it is most preferred to form the thin film by vacuum deposition.

[0031] The vapor deposition process used as the PVD method involves heating a target such as a metal, metal oxide, metal hydroxide, or resin (hereinafter, these vapor deposition raw materials may be collectively referred to as the target) with various heat sources to evaporate it, and then depositing it as an amorphous or crystalline film on the surface of a substrate maintained at a lower temperature. This method can be used either as a batch method in which the entire processing surface is processed at once, or as a method in which the substrate or reaction tank is moved to continuously process equipment or different processing surfaces.

[0032] The vapor deposition process of the present invention can be carried out under pressurized, normal pressure, reduced pressure, vacuum, and its swing, in air, or in an inert gas atmosphere. By carrying out the process under reduced pressure or vacuum, it is possible to improve the evaporation rate and lower the evaporation temperature, and by applying pressure, it is possible to promote the deposition of the evaporated material. Furthermore, by using a vacuum or inert atmosphere, it is possible to control the oxidation of the metal, metal oxide, metal hydroxide, etc., and the support. Furthermore, if oxidation during the vapor deposition process can be controlled or tolerated, it is also possible to carry out the process in an air atmosphere, taking cost into consideration.

[0033] In the present invention, a desirable thin film can be obtained depending on the purpose by adjusting the deposition conditions. The conditions include the pressure in the chamber and the contact time between the target vapor, the molecules present in the atmosphere, and the substrate surface in order to control the chemical structure of the target vapor. By controlling this time, the composition of the deposited thin film can be controlled. Furthermore, the structure of the thin film surface can be controlled by contacting the thin film with oxygen or water vapor after deposition.

[0034] Controlling the chemical structure of the target deposition material means, for example, adding water vapor or oxygen during deposition to obtain a compound in which a hydroxyl group or oxygen is added to the target metal as a deposition layer, and deposition conditions can be appropriately considered depending on the desired deposition film.

[0035] The sputtering method in the present invention is not particularly limited as long as the effects of the present invention can be obtained, and can be selected from DC sputtering, RF sputtering, magnetron sputtering, ion beam sputtering, RF magnetron sputtering, etc., but magnetron sputtering and RF magnetron sputtering are preferred because they allow highly efficient sputtering. －４ It is desirable to carry out the process in a processing space such as a chamber that is decompressed to 0.2 Pa or less and into which an inert gas (e.g., argon) has been introduced. In the processing space, a target serving as the raw material for the thin film and a substrate are placed facing each other. A permanent magnet and, if necessary, a holder or other device for holding the target are placed behind the target.

[0036] The magnetic field of the permanent magnet can constrain the spiral trajectory of electrons present in the processing space, generating a high-density plasma region. The presence of the high-density plasma region promotes ionization of the inert gas, and the ions collide with the target, generating target microparticles, which then adhere to the substrate, forming a thin film.

[0037] The RF output during RF magnetron sputtering is not particularly limited and may be adjusted to achieve an appropriate film formation rate. The temperature of the substrate during film formation is preferably controlled to be between room temperature and approximately 100°C.

[0038] The thickness of the vapor-deposited layer (A) is preferably 10 nm or more and 500 nm or less as the thickness of the layer at which gas barrier properties are exhibited. If the layer thickness is thinner than 10 nm, there may be areas where sufficient gas barrier properties are not ensured, and problems such as variations in gas barrier properties within the substrate surface may occur. If the layer thickness is thicker than 500 nm, the residual stress within the vapor-deposited layer (A) may increase, causing cracks in the vapor-deposited layer (A) under high-temperature and high-humidity environments, resulting in problems of reduced gas barrier properties. From the viewpoint of ensuring flexibility, the lower limit is more preferably 20 nm or more and the upper limit is more preferably 300 nm or less. The thickness of the vapor-deposited layer (A) can usually be measured by cross-sectional observation using a transmission electron microscope (TEM).

[0039] The vapor-deposited layer (A) may be a mixture of aluminum oxide and silicon oxide. Among these, a composite oxide of aluminum oxide and silicon oxide is more preferred. That is, in this composite oxide, the mixing ratio of aluminum oxide and silicon oxide is preferably 20% by mass or more and 70% by mass or less of Al (aluminum) in terms of the mass ratio of metal atoms, i.e., the mass ratio of metal atoms. When it is 20% by mass or more, excellent gas barrier properties are achieved. When it is 70% by mass or less, excessive hardness of the vapor-deposited layer (A) can be prevented.

[0040] (Vapor-deposited layer (B)) A vapor-deposited layer (B) of a divalent metal oxide (B) is provided on the vapor-deposited layer (A). The divalent metal oxide (B) is preferably one or more selected from zinc oxide, magnesium oxide, calcium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, and copper oxide, more preferably one or more selected from zinc oxide, magnesium oxide, and calcium oxide, and particularly preferably zinc oxide. These metal compounds may be used alone or in combination of two or more. Like the vapor-deposited layer (A), the vapor-deposited layer (B) is preferably formed by a vapor phase thin film formation method.

[0041] The thickness of the vapor-deposited layer (B) is not particularly limited as long as the effects of the present invention can be obtained. As described above, the thickness of the vapor-deposited layer (B) is not particularly limited, but is preferably 1 to 200 nm in order to obtain a sufficient protective effect for the vapor-deposited layer (A), and is more preferably 3 to 150 nm, and particularly preferably 5 to 100 nm in order to ensure the plasticity of the entire laminate.

[0042] The vapor deposition process used as the PVD method involves heating a target such as a metal, metal oxide, metal hydroxide, or resin (hereinafter, these vapor deposition raw materials may be collectively referred to as the target) with various heat sources to evaporate it, and then depositing it as an amorphous or crystalline film on the surface of a substrate maintained at a lower temperature. This method can be used either as a batch method in which the entire processing surface is processed at once, or as a method in which the substrate or reaction tank is moved to continuously process equipment or different processing surfaces.

[0043] The vapor deposition process of the present invention can be carried out under pressurized, normal pressure, reduced pressure, vacuum, and its swing, in air, or in an inert gas atmosphere. By carrying out the process under reduced pressure or vacuum, it is possible to improve the evaporation rate and lower the evaporation temperature, and by applying pressure, it is possible to promote the deposition of the evaporated material. Furthermore, by using a vacuum or inert atmosphere, it is possible to control the oxidation of the metal, metal oxide, metal hydroxide, etc., and the support. Furthermore, if oxidation during the vapor deposition process can be controlled or tolerated, it is also possible to carry out the process in an air atmosphere, taking cost into consideration.

[0044] In the present invention, a desirable thin film can be obtained depending on the purpose by adjusting the deposition conditions. The conditions include the pressure in the chamber and the contact time between the target vapor, the molecules present in the atmosphere, and the substrate surface in order to control the chemical structure of the target vapor. By controlling this time, the composition of the deposited thin film can be controlled. Furthermore, the structure of the thin film surface can be controlled by contacting the thin film with oxygen or water vapor after deposition.

[0045] Controlling the chemical structure of the target deposition material means, for example, adding water vapor or oxygen during deposition to obtain a compound in which a hydroxyl group or oxygen is added to the target metal as a deposition layer, and deposition conditions can be appropriately considered depending on the desired deposition film.

[0046] The sputtering method used in the present invention is not particularly limited as long as the effects of the present invention can be obtained, and can be selected from DC sputtering, RF sputtering, magnetron sputtering, ion beam sputtering, RF magnetron sputtering, etc., but magnetron sputtering and RF magnetron sputtering are preferred because they enable highly efficient sputtering. Magnetron sputtering is preferably performed in a processing space, such as a chamber, which is decompressed to 1×10 Pa or less and into which an inert gas (e.g., argon) has been introduced. A target, which serves as the raw material for the thin film, and a substrate are arranged facing each other in the processing space. A permanent magnet and, if necessary, a device such as a holder for holding the target are arranged behind the target.

[0047] The magnetic field of the permanent magnet can constrain the spiral trajectory of electrons present in the processing space, generating a high-density plasma region. The presence of the high-density plasma region promotes ionization of the inert gas, and the ions collide with the target, generating target microparticles, which then adhere to the substrate, forming a thin film.

[0048] The RF output during RF magnetron sputtering is not particularly limited and may be adjusted to achieve an appropriate film formation rate. The temperature of the substrate during film formation is preferably controlled to be between room temperature and approximately 100°C.

[0049] In the gas barrier film of the present invention, the ratio of the metal in the vapor-deposited layer (B) to the metal in the vapor-deposited layer (A) measured by fluorescent X-ray intensity is preferably in the range of 0.5:100 to 90:100, more preferably 2:100 to 50:100. This range provides excellent flex resistance. In the present invention, the fluorescent X-ray intensity was measured using a handheld fluorescent X-ray measuring device (device name: X-MET8000, manufactured by Horiba, Ltd.), and the ratio of the metal in the vapor-deposited layer (A) to the metal in the vapor-deposited layer (B) on the film surface (metal in the vapor-deposited layer (B) / metal in the vapor-deposited layer (A)) was calculated from the intensity obtained by the measurement.

[0050] (Coating Layer) After laminating the (A) layer and the (B) layer, the gas barrier film of the present invention may have a coating layer formed by coating a coating agent on the surface of the (B) layer or on the back surface of the plastic film. In the present invention, the coating method for these coating layers is not particularly limited, and known and commonly used coating methods such as roll coating, spraying, spin coating, blade coating, dipping, screen printing, inkjet printing, doctor roll coating, doctor blade coating, curtain coating, slit coating, and dispensing can be used. Examples of the coating layer include a hard coat coating layer formed by coating a hard coat agent for protecting the gas barrier film of the present invention, and a coating layer having various functions, such as a heat-resistant coating layer formed by coating a heat-resistant coating agent described below.

[0051] The gas barrier film of the present invention has excellent flexibility. Specifically, the loop stiffness value a (g / cm) calculated by the formula (1) described below is preferably in the range of +1.0% to +30.0%. A value below +1.0% tends to make it difficult to obtain the protective effect of the vapor-deposited layer (A) when bent, while a value above +30.0% tends to make the film hard and the vapor-deposited layer (B) more susceptible to cracking. In the present invention, the loop stiffness value a (g / cm) is a parameter that represents the stiffness of a film such as a stretched plastic film. It can be used to evaluate not only single-layer films such as stretched plastic films, but also multilayer films such as vapor-deposited films and laminated films. The loop stiffness value can be measured, for example, by cutting a film into strips, attaching them to a device in a loop shape, and reading the force when crushed by a constant load for a certain distance. In the present invention, the loop stiffness value was evaluated using a measuring device called "Loop Stiffness Tester (registered trademark)" manufactured by Toyo Seiki Seisaku-sho, Ltd.

[0052] Since the measurement of the loop stiffness value a (g / cm) depends on the thickness of each material, in order to evaluate the change due to deposition, the loop stiffness value a1 of a film having only the vapor-deposited layer (A) and the loop stiffness value a2 of a film having the vapor-deposited layer (B) vapor-deposited on the vapor-deposited layer (A) were measured, and the change was evaluated as a rate of change (%) calculated by the following formula (1): Formula (1) (a2-a1) / (a1)×100 (%)

[0053] (Second Layer) The gas barrier film of the present invention can be bonded to another plastic film using an adhesive. Alternatively, another plastic layer can be formed on the gas barrier film by extrusion. (Hereinafter referred to as the second layer) The second layer may be made of the same type of resin material as the plastic film, or a different resin material. When the gas barrier film of the present invention is used as a packaging material, a polyolefin resin having heat sealing suitability can be selected, assuming that the second layer will be used as a sealant layer. Examples of the heat-sealable layer include polyethylene resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), very low-density polyethylene (VLDPE), polypropylene (CPP), ethylene-propylene copolymers, and polymethylpentene; ethylene-vinyl acetate copolymers (EVA), ethylene-methyl methacrylate copolymers (EMMA), ethylene-ethyl acrylate copolymers (EEA), ethylene-methyl acrylate (EMA) copolymers, ethylene-ethyl acrylate-maleic anhydride copolymers (E-EA-MAH), ethylene-acrylic acid copolymers (EAA), and ethylene-methacrylic acid copolymers (EMAA); and ionomers of ethylene-acrylic acid copolymers and ionomers of ethylene-methacrylic acid copolymers, which may be used alone or in combination of two or more. When the second layer is a heat-sealable layer, its thickness can be adjusted appropriately depending on the purpose, but is, for example, 1 μm to 10 μm, and more preferably 3 μm to 10 μm, from the viewpoints of aroma retention and heat-sealability.

[0054] (Adhesive) The adhesive used to bond the second layer to the gas barrier film of the present invention may be any adhesive that can be used in a general-purpose lamination method. Examples of lamination methods include dry lamination, wet lamination, non-solvent lamination, and extrusion lamination. The adhesive becomes an adhesive layer after curing or drying.

[0055] The adhesive used in the dry lamination may be, for example, a one-component or two-component curable or non-curable vinyl, (meth)acrylic, polyamide, polyester, polyether, polyurethane, epoxy, rubber, or other solvent-based, aqueous, or emulsion adhesive. A two-component curable adhesive may be a two-component curable adhesive composed of a polyol and an isocyanate compound. The laminating adhesive may be applied by, for example, direct gravure roll coating, gravure offset roll coating, kiss coating, reverse roll coating, Fountain coating, transfer roll coating, or other methods. For example, the DIC Dry series manufactured by DIC Corporation may be preferably used.

[0056] Various types of adhesives can also be used, and it is preferable to use a pressure-sensitive adhesive. Examples of pressure-sensitive adhesives include rubber-based adhesives obtained by dissolving polyisobutylene rubber, butyl rubber, or mixtures thereof in organic solvents such as benzene, toluene, xylene, and hexane, or these rubber-based adhesives blended with tackifiers such as abiethylene acid rosin ester, terpene-phenol copolymer, and terpene-indene copolymer, and acrylic-based adhesives obtained by dissolving an acrylic copolymer having a glass transition temperature of −20° C. or lower, such as a 2-ethylhexyl acrylate-n-butyl acrylate copolymer or a 2-ethylhexyl acrylate-ethyl acrylate-methyl methacrylate copolymer, in an organic solvent.

[0057] The adhesive may be a functional adhesive. For example, an adhesive having gas barrier properties may be the oxygen barrier adhesive PASLIM series manufactured by DIC Corporation, which is a two-component reactive adhesive of polyester polyol and an isocyanate compound. The gas barrier adhesive becomes a gas barrier adhesive layer after curing or drying. Use of a gas barrier adhesive is preferred because it can further enhance the gas barrier properties of the laminate of the present invention.

[0058] When the adhesive is solvent-based, the adhesive is applied to one substrate using a roll such as a gravure roll, and the organic solvent is evaporated by heating in an oven or the like, and then the other substrate is laminated to obtain the laminate of the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably room temperature to 80°C, and the aging time is preferably 12 to 240 hours.

[0059] When the adhesive is solventless, the aroma-retaining adhesive, which has been preheated to about 40°C to 100°C, is applied to one substrate using a roll such as a gravure roll, and the other substrate is immediately laminated to obtain the laminate of the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably room temperature to 70°C, and the aging time is preferably 6 to 240 hours.

[0060] The amount of adhesive to be applied is adjusted as appropriate. In the case of a solvent-based adhesive, for example, the solid content is 1 g / m ２ 10g / m or more ２ Preferably 1 g / m or less ２ 5g / m or more ２ In the case of a solvent-free type, the amount of adhesive applied is adjusted to, for example, 1 g / m ２ 10g / m or more ２ Preferably 1 g / m or less ２ 5g / m or more ２ The following is the result.

[0061] (Heat-Resistant Resin Layer) The gas barrier film of the present invention may have a heat-resistant coating layer. The heat-resistant coating layer is a coating layer of a heat-resistant coating agent (hereinafter, sometimes simply referred to as a heat-resistant coating agent). Commercially available products can be used as the heat-resistant coating agent. Examples of commercially available products include SUNSYS FS241 manufactured by Sun Chemical Co., DH-S004 / DH-HARDENER P-60 manufactured by DIC Corporation, and ThermaGloss (registered trademark) 463 manufactured by Michelman.

[0062] Also preferred are heat-resistant coating agents containing compounds having a cellulose skeleton, a benzene ring skeleton, an isocyanuric ring skeleton, or an alicyclic skeleton, whose homopolymer glass transition temperature (hereinafter sometimes referred to as Tg) is 100°C or higher. Specific examples include cellulose derivatives such as nitrocellulose, cellulose acetate, cellulose propionate, and cellulose butyrate; polyester resins having a benzene ring such as phthalic acid, naphthalenedicarboxylic acid, and an ethylene oxide (hereinafter sometimes referred to as EO) adduct of bisphenol A, and / or an alicyclic skeleton such as cyclopentanediol and dimethyloltricyclodecane; aromatic isocyanates such as diphenylmethane diisocyanate, toluene diisocyanate, xylene diisocyanate, and naphthalene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate and norbornene diisocyanate; and / or urethane resins obtained by combining isocyanuric triisocyanate with a polyol and / or tris(2-hydroxyethyl)isocyanurate. Polyisocyanates using the above-mentioned isocyanates may also be used as the curing agent. In addition, compounds having a benzene ring and an unsaturated double bond, such as styrene and phenoxydiethylene glycol acrylate, and / or compounds having an alicyclic structure and an unsaturated double bond, such as isobornyl acrylate and dicyclopentanyl acrylate, and radical copolymers such as (meth)acrylates are also preferably used. Furthermore, in consideration of adhesion to olefin films, a resin with a low Tg may be mixed in and used. The total amount of the cellulose skeleton, benzene ring skeleton, isocyanuric ring skeleton, and alicyclic skeleton of the aforementioned compounds is preferably 20 to 99% by mass, and more preferably 30 to 95% by mass, of the solid content of the heat-resistant coating layer (A).

[0063] The heat-resistant coating agent may be colored. The colorant is not particularly limited, and examples thereof include inorganic pigments, organic pigments, and dyes used in general inks, paints, and recording agents, such as those used in the printing layer (E) described below. Among these, pigments are preferred. Examples of organic pigments include soluble azo pigments, insoluble azo pigments, azo pigments, phthalocyanine pigments, halogenated phthalocyanine pigments, anthraquinone pigments, anthanthrone pigments, dianthraquinonyl pigments, anthrapyrimidine pigments, perylene pigments, perinone pigments, quinacridone pigments, thioindigo pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, azomethine azo pigments, flavanthrone pigments, diketopyrrolopyrrole pigments, isoindoline pigments, indanthrone pigments, and carbon black pigments. Other examples include carmine 6B, lake red C, permanent red 2B, disazo yellow, pyrazolone orange, carmine FB, cromophtal yellow, cromophtal red, phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone magenta, quinacridone red, indanthrone blue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, daylight fluorescent pigments, etc. In addition, both non-acid-treated pigments and acid-treated pigments can be used.

[0064] Examples of inorganic pigments include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, lithopone, antimony white, and gypsum. Among the inorganic pigments, titanium oxide is particularly preferred. Titanium oxide exhibits a white color and is preferred in terms of coloring power, hiding power, chemical resistance, and weather resistance. From the viewpoint of printing performance, titanium oxide is preferably treated with silica and / or alumina. Examples of inorganic pigments other than white include aluminum particles, mica, bronze powder, chrome vermilion, yellow lead, cadmium yellow, cadmium red, ultramarine, Prussian blue, red iron oxide, yellow iron oxide, iron black, and zircon. Aluminum is in powder or paste form, but is preferably used in paste form from the viewpoints of handleability and safety. Whether leafing or non-leafing is used is appropriately selected from the viewpoints of brightness and density.

[0065] Furthermore, the heat-resistant coating agent preferably uses inorganic fine particles such as alumina, magnesia, titania, zirconia, and silica (quartz, fumed silica, precipitated silica, silicic anhydride, fused silica, crystalline silica, ultrafine amorphous silica, etc.) as aggregates due to their excellent heat resistance. Alternatively, boron nitride, aluminum nitride, alumina oxide, titanium oxide, magnesium oxide, zinc oxide, silicon oxide, etc. are preferred due to their excellent thermal conductivity. The inorganic fine particles may be used alone or in combination. The shape of the silica fine particles is not particularly limited, and spherical, hollow, porous, rod-like, plate-like, fibrous, or amorphous silica may be used. For example, commercially available hollow silica fine particles such as Silinax manufactured by Nittetsu Mining Co., Ltd. may be used.

[0066] The primary particle diameter of the inorganic fine particles is preferably in the range of 5 nm to 100 μm. If the diameter is 1 nm or more, the inorganic fine particles are well dispersed in the dispersion, and if the diameter is 100 μm or less, the strength of the cured product is good. It is more preferably 10 nm to 20 μm. The inorganic fine particles can be blended in a ratio of 5 to 90 wt % based on the total solid content of the heat-resistant coating agent and the inorganic fine particles, and the blending amount can be changed as needed depending on the purpose. In particular, a ratio of 20 mass % or more is preferable.

[0067] Waxes, silicon additives, and organic beads can be added to the heat-resistant coating agent to prevent scratches on the coated film, prevent blocking during laminate formation, and improve processability during bag manufacturing after the laminate is produced. Specifically, waxes such as amide wax, polypropylene wax, polyethylene wax, paraffin wax, carnauba wax, and rice wax, ethylene oxide (EO) adducts of dimethylsiloxane, silicon additives of modified silicon, and organic beads made of acrylic, nylon, urethane, or epoxy can be added.

[0068] The solvent used in the heat-resistant coating agent is not particularly limited, and examples thereof include water, aromatic hydrocarbon organic solvents such as toluene, xylene, Solvesso #100, Solvesso #150, etc., aliphatic hydrocarbon organic solvents such as hexane, methylcyclohexane, heptane, octane, decane, etc., and various ester organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, normal propyl acetate, butyl acetate, amyl acetate, ethyl formate, butyl propionate, etc. Examples of water-miscible organic solvents include alcohols such as methanol, ethanol, propanol, butanol, and isopropyl alcohol; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; and glycol ethers such as ethylene glycol (mono- and di-)methyl ether, ethylene glycol (mono- and di-)ethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono- and di-)methyl ether, diethylene glycol (mono- and di-)ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono- and di-)methyl ether, propylene glycol (mono- and di-)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol (mono- and di-)methyl ether. These can be used alone or in combination of two or more. Furthermore, to more effectively carry out coating, an antifoaming agent or a leveling agent can be used.

[0069] The amount of the heat-resistant resin layer to be applied is appropriately selected depending on the application, but the amount of the applied heat-resistant resin layer after drying is preferably 0.01 to 100 g / m ２ is preferred, and 0.1 to 50 g / m ２ More preferably, 0.5 to 3 g / m ２ is particularly preferred.

[0070] (Laminate Structure) An example of a specific embodiment of the gas barrier film of the present invention is given below. Of course, the laminate of the present invention is not limited to this embodiment. Plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Plastic film / printed layer / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Printed layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Plastic film / printed layer / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Plastic film / printed layer / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Printed layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer

[0071] Plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Plastic film / printed layer / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / printed layer / gas barrier adhesive layer / second layer Printed layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Plastic film / printed layer / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / printed layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Printed layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer

[0072] Heat-resistant resin layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / printed layer / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Heat-resistant resin layer / printed layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Heat-resistant resin layer / plastic film / printed layer / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Heat-resistant resin layer / printed layer / plastic film / deposited layer (A) / deposited layer (B) / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer

[0073] Heat-resistant resin layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / printed layer / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / printed layer / gas barrier adhesive layer / second layer Heat-resistant resin layer / printed layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Heat-resistant resin layer / plastic film / printed layer / vapor deposition layer (A) / vapor deposition layer (B) / vapor deposition protective coating layer / gas barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Heat-resistant resin layer / plastic film / vapor-deposited layer (A) / vapor-deposited layer (B) / vapor-deposited protective coating layer / printed layer / gas-barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer Heat-resistant resin layer / printed layer / plastic film / vapor-deposited layer (A) / vapor-deposited layer (B) / vapor-deposited protective coating layer / gas-barrier adhesive layer / substrate used as intermediate layer / adhesive layer / second layer

[0074] Heat-resistant resin layer / plastic film / gas barrier adhesive layer / second layer Heat-resistant resin layer / plastic film / printed layer / gas barrier adhesive layer / second layer Heat-resistant resin layer / printed layer / plastic film / gas barrier adhesive layer / second layer A coating layer that imparts functions such as release properties and antistatic properties may also be present on the plastic film.

[0075] (Packaging Material) The laminate of the present invention can be used as a multilayer packaging material for the purpose of protecting food, medicines, etc. When used as a multilayer packaging material, the layer structure can be changed depending on the contents, usage environment, and usage form. In addition, the packaging of the present invention may be appropriately provided with an easy-open treatment or resealable means.

[0076] Taking a laminate having a sealant layer as an example of the packaging material of the present invention, the laminates are stacked with the sealant layer surfaces facing each other, and then the peripheral edges are heat-sealed to form a bag. Examples of bag-making methods include folding or stacking the laminate of the present invention so that the inner layer surfaces (sealant layer surfaces) face each other, and heat-sealing the peripheral edges using, for example, a side seal, two-sided seal, three-sided seal, four-sided seal, envelope seal, flared seal, flat-bottom seal, square-bottom seal, gusset seal, or other heat seal methods. The packaging material of the present invention can take various forms depending on the contents, usage environment, and usage pattern. Self-standing packaging materials (standing pouches) are also possible. Heat sealing can be performed using known methods such as bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, and ultrasonic seal.

[0077] When the plastic film and second substrate of the laminate of the present invention do not function as a sealant layer that serves as a heat-sealed portion when forming a packaging material, a further sealant layer may be added. The sealant layer may be an additional substrate bonded with the adhesive of the present invention, or may be an adhesive layer made of the adhesive of the present invention.

[0078] The packaging material of the present invention is filled with contents through its opening, and then the opening is heat-sealed to produce a product using the packaging material of the present invention. Examples of contents to be filled include foods such as rice crackers, bean snacks, nuts, biscuits, cookies, wafer snacks, marshmallows, pies, semi-dried cakes, candies, and snacks; staple foods such as bread, snack noodles, instant noodles, dried noodles, pasta, aseptically packaged cooked rice, porridge, rice porridge, packaged rice cakes, and cereal foods; processed agricultural products such as pickles, boiled beans, natto, miso, frozen tofu, tofu, nametake mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen vegetables, and processed potatoes; processed livestock products such as ham, bacon, sausages, processed chicken, and corned beef; and processed fish ham and meat products. Examples of such foods include processed seafood products such as sausages, fish paste products, kamaboko, nori seaweed, tsukudani (simmered foods in soy sauce), bonito flakes, salted fish, smoked salmon, and spicy mentaiko; fruit pulp such as peaches, mandarin oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; cooked foods such as frozen and chilled prepared dishes, including hamburgers, meatballs, fried seafood, gyoza, and croquettes; dairy products such as butter, margarine, cheese, cream, instant creamy powder, and infant formula; liquid seasonings, retort curry, and pet food.

[0079] In addition, the present invention can also be used as a packaging material for various non-food products, such as cigarettes, disposable body warmers, medicines such as infusion packs, liquid laundry detergent, liquid kitchen detergent, liquid bath detergent, liquid bath soap, liquid shampoo, liquid conditioner, cosmetics such as lotion and emulsion, vacuum insulation materials, batteries, etc.

[0080] In particular, the packaging material of the present invention has excellent hydrogen sulfide adsorption capacity, and therefore exhibits its performance when the contents contain sulfur. For example, since it has the effect of reducing the retort odor generated during retort, it is suitable as a packaging material for retort pouch foods. Furthermore, since it can adsorb hydrogen sulfide generated by the penetration of moisture, it is also suitable as an exterior material for all-solid-state lithium-ion batteries.

[0081] (Recycled Plastics) The laminate or packaging material of the present invention can also be processed directly using various known recycling plastic processing methods to produce recycled plastics. As an example of a specific embodiment, recycled plastics can be obtained by a production method including a step of crushing the recovered material obtained by separating the laminate of the present invention into each substrate, or the laminate or packaging material of the present invention, a step of melt-kneading the crushed film pieces, and a step of pelletizing the melt-kneaded mixture.

[0082] The crusher used for crushing (pulverization) may be any known crusher and is not particularly limited. The crushed film pieces are then physically blended using melt kneading, solvent cast blending, latex blending, polymer complexing, or the like. The melt kneading method is particularly common. Examples of kneading devices include a tumbler, Henschel mixer, rotary mixer, super mixer, ribbon tumbler, and V-blender. The film is melt-kneaded using such a kneading device and then pelletized. A single-screw or multi-screw extruder is typically used for melt kneading and pelletization. The film pieces may be fed as they are or may be subjected to a compression volume reduction treatment with or without heating before being fed. In addition to these extruders, a Banbury mixer, roller, Ko-kneader, blast mill, Prabender Bloutograph, or the like may also be used, and these may be operated batchwise or continuously. Alternatively, the film may be used as a molding resin without being melt-kneaded, and melt-kneaded in the heating barrel of a molding machine.

[0083] The present invention will be described in more detail below with reference to specific synthesis examples and examples, but the present invention is not limited to these examples. In the following examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified.

[0084] Examples 1 to 7: A zinc target was placed in a crucible in a vacuum deposition apparatus (VPC-1100 manufactured by ULVAC Techno Co., Ltd.) capable of EB heating and resistance heating. The apparatus was evacuated to a vacuum of 3.0 × 10-3 Pa and heated to a film deposition rate of 10 Å / s to 500 Å / s while monitoring the deposition rate using a quartz crystal oscillator. Oxygen was introduced as the process gas, and a zinc oxide (hereinafter abbreviated as ZnO) film was fabricated on a biaxially oriented polypropylene film (hereinafter abbreviated as OPP film) on which aluminum oxide (hereinafter abbreviated as AlOx) was deposited to a thickness of 20 nm, with the total light transmittance set at 90% or higher. The gas barrier films of Examples 1 to 7 were obtained, in which the thickness of the ZnO film was varied by controlling the transport speed of the AlOx OPP film and thereby controlling the deposition time.

[0085] Example 8 A magnesium target was placed in a crucible in a vacuum deposition apparatus (VPC-1100 manufactured by ULVAC TECHNO, Inc.) capable of EB heating and resistance heating as a PVD deposition apparatus, and the apparatus was evacuated to a vacuum of 3.0 × 10 Pa. Heating was performed so that a film could be formed at a film formation rate in the range of 10 Å / s to 500 Å / s while checking the film formation rate with a quartz crystal oscillator. Oxygen was introduced as the process gas, and a magnesium oxide (hereinafter abbreviated as MgO) film was formed on an AlOx OPP film, with a total light transmittance of 90% or more as an index, to obtain the gas barrier film of Example 8.

[0086] Example 9 A PVD deposition apparatus was used, and zinc was placed in a crucible as a target in a vacuum deposition apparatus (VPC-1100 manufactured by ULVAC TECHNO, Inc.) capable of EB heating and resistance heating. The apparatus was evacuated to a vacuum of 3.0 × 10 Pa, and the deposition rate was monitored using a quartz crystal oscillator while heating the crucible so as to form a film at a rate of 10 Å / s to 500 Å / s. Oxygen was introduced as the process gas, and a ZnO film was formed on a polyethylene terephthalate film (hereinafter referred to as PET film) on which AlOx had been deposited to a thickness of 20 nm (hereinafter referred to as AlOxPET film), with a total light transmittance of 90% or more as an index. Thus, the gas barrier film of Example 9 was obtained.

[0087] Example 10 A PVD deposition apparatus was used, and zinc was placed in a crucible as a target in a vacuum deposition apparatus (VPC-1100 manufactured by ULVAC TECHNO, Inc.) capable of EB heating and resistance heating. The apparatus was evacuated to a vacuum of 3.0 × 10 Pa, and the deposition rate was monitored using a quartz crystal oscillator while heating the crucible so as to form a film at a rate of 10 Å / s to 500 Å / s. Oxygen was introduced as the process gas, and a ZnO film was formed on a film (hereinafter referred to as SiOxPET film) in which silicon oxide (hereinafter referred to as SiOx) had been deposited to a thickness of 30 nm on a PET film, with a total light transmittance of 90% or more as an indicator. Thus, the gas barrier film of Example 10 was obtained.

[0088] Comparative Example 1 An AlOx OPP film was used, in which AlOx was deposited to a thickness of 20 nm on a biaxially stretched polypropylene film (hereinafter abbreviated as OPP film) on which no ZnO was deposited.

[0089] Comparative Example 2 An AlOx PET film (thickness: 12 μm, AlOx film thickness: 20 nm) on which no ZnO was deposited was used.

[0090] Comparative Example 3 A SiOx PET film (thickness: 12 μm, SiOx film thickness: 30 nm) on which no ZnO was deposited was used, and evaluation was carried out in the same manner as in the example.

[0091] (Comparative Example 4) A PVD deposition apparatus was used, a vacuum deposition apparatus capable of EB heating and resistance heating (VPC-1100 manufactured by ULVAC Techno Co., Ltd.), in which zinc was placed as a target in a crucible. The apparatus was evacuated to a vacuum of 3.0 × 10 Pa, and the deposition rate was monitored using a quartz crystal oscillator while heating the crucible so that a film could be deposited at a rate ranging from 10 Å / s to 500 Å / s. Oxygen was introduced as the process gas, and a ZnO film (20 nm thick) was formed on an OPP film, with a total light transmittance of 90% or higher as the target. Next, aluminum was placed as a target in the crucible, and an AlOx film (40 nm thick) was formed on the previously prepared ZnO deposition film in the same manner, yielding the film of Comparative Example 4.

[0092] (Preparation of Evaluation Films) The evaluation films used were Film 1, which was the film of the Examples and Comparative Examples used as is, and Laminated Film 2, which was the film of the Examples and Comparative Examples bonded to a non-oriented polypropylene film (hereinafter abbreviated as CPP film) using an adhesive.

[0093] (Method for manufacturing laminate film 2) The films of the Examples and Comparative Examples were coated on the vapor-deposited layer (B) to a dry film thickness of 2.5 μm using a reactive adhesive prepared by blending Dikdry LX-830 and KW-75 (both manufactured by DIC) in a blending ratio of 10 / 1.5 and adding ethyl acetate so that the nonvolatile content was 25%. The diluted solvent was evaporated using a dryer set at 50° C., and the film was then laminated with a CPP film (P1128, manufactured by Toyobo Co., Ltd.). Aging was carried out at 40° C. for 3 days, and laminate film 2 was obtained.

[0094] (Method for producing laminate film 3) The laminate film 2 was adjusted to a size of 30 cm x 20 cm, and a bending test was carried out in accordance with ASTM F392 using a Gelbo Flex Tester (manufactured by Tester Sangyo Co., Ltd.) under the conditions of 440° / 90 mm linear motion 65 mm, 23°C, and 30 bending cycles, to obtain a laminate film 3.

[0095] (Evaluation Method) <X-ray fluorescence> The X-ray fluorescence intensity was measured for Film 1. Measurement was performed using a handheld X-ray fluorescence measurement device (device name: X-MET8000, manufactured by Horiba, Ltd.), and the ratio of metal in the vapor-deposited layer (A) and the vapor-deposited layer (B) on the film surface (metal in vapor-deposited layer (B) / metal in vapor-deposited layer (A)) was calculated from the intensity obtained by the measurement.

[0096] <Total Light Transmittance> The total light transmittance was measured for Film 1. Based on JIS K7361 (1997), it was measured using a haze meter NDH7000 (manufactured by Nippon Denshoku Industries Co., Ltd.). The measurement was performed on three gas barrier films cut into a size of 10 cm length x 10 cm width. The measurement was performed five times for each film, and the average value of a total of 15 measurements was taken as the total light transmittance.

[0097] <Loop Stiffness Test> The loop stiffness value a (g / cm) was measured for film 1. A loop stiffness tester (manufactured by Toyo Seiki Seisakusho, Ltd.) was used. The sample width for measurement was 25 mm, the loop length was 80 mm, and the crushing distance was 10 mm, and the force was read 2 minutes after crushing. The loop stiffness value a1 of a film having only the vapor-deposited layer (A) and the loop stiffness value a2 of a film in which the vapor-deposited layer (B) was vapor-deposited on the vapor-deposited layer (A) were measured, and the loop stiffness was evaluated as the rate of change (%) calculated by the following formula (1): Formula (1) (a2-a1) / (a1)×100 (%)

[0098] <Evaluation of gas barrier properties: oxygen permeability> Oxygen permeability (OTR) was measured for films 1, 2, and 3. In accordance with JIS-K7126 (constant pressure method), an oxygen permeability measuring device OX-TRAN2 / 22 manufactured by Mocon was used, and measurements were carried out in an atmosphere of temperature 23°C and humidity 0% RH, and in an atmosphere of temperature 23°C and humidity 90% RH. RH represents relative humidity. The unit of oxygen permeability is cc / day·atm·m2.

[0099] <Evaluation of Gas Barrier Property: Water Vapor Transmission Rate> Water vapor transmission rate (MVTR) was measured for Films 1, 2, and 3. In accordance with JIS-K7129, measurements were made using a Water Vapor Transmission Rate Measuring Device 7001 manufactured by Illinois Corporation under an atmosphere of a temperature of 40°C and a humidity of 90% RH. The unit of oxygen transmission rate is g / m2·day.

[0100] <Evaluation of Hydrogen Sulfide Adsorption Capacity> The hydrogen sulfide adsorption capacity was evaluated for laminate film 2. The film was cut to a size of 5 cm x 5 cm, placed in a scent bag, and heat-sealed. 3 L of air was sealed inside, and hydrogen sulfide gas was added to a concentration of 20 ppm. This was left to stand, and after a certain period of time (10 minutes, 1 hour, 3 hours, 6 hours, and 24 hours), the gas concentration inside the bag was measured using a gas detector tube. An undeposited film was used as a control, and films that showed a decrease in hydrogen sulfide gas concentration were judged to have hydrogen sulfide adsorption capacity.

[0101] The film configurations and evaluation results of the examples are shown in Table 1, and the film configurations and evaluation results of the comparative examples are shown in Table 2.

[0102]

[0103]

Claims

1. A gas barrier film characterized in that a vapor-deposited layer of aluminum oxide and / or silicon oxide (A) and a vapor-deposited layer of zinc oxide (B) are laminated in this order on a plastic film.

2. The gas barrier film according to claim 1, wherein the thickness of the vapor-deposited layer (B) is in the range of 1 to 200 nm.

3. The gas barrier film according to claim 1, wherein the ratio of metal in the deposited layer (B) to metal in the deposited layer (A), as determined by X-ray fluorescence intensity, is in the range of 0.5:100 to 90:

100.

4. A packaging containing the gas barrier film described in any one of claims 1 to 3.