Gas Barrier Film

Abstract

A gas barrier film that combines good gas barrier properties with good optical properties is provided. The gas barrier film 1 comprises a substrate layer 10 and a silicon dioxide film on one or both sides of the substrate layer. x Sn y O (1-x-y) The gas barrier layer 20 is a vapor-deposited film deposited as a film. The surface of the gas barrier layer, as measured by X-ray photoelectron spectroscopy, has a ratio of oxygen to the sum of silicon and tin (O / (Si+Sn)) greater than 1.00 and less than 1.70, a ratio of tin to silicon (Sn / Si) greater than 0.15 and less than 5.00, and a ratio (metallic Sn / Sn) of the area of the Sn3d5 / 2 peak among the metallic Sn peaks representing metallic bonds to the area of the metallic Sn peak in the Sn3d5 / 2 peak is 0.05 or more and 0.70 or less.

Description

[Technical Field]

[0001] The present invention relates to a gas barrier film, and more particularly to a gas barrier film suitable for packaging foods, medicines, precision electronic parts, and the like. [Background technology]

[0002] Packaging materials used for foods and pharmaceuticals are often required to have gas barrier properties that block oxygen, water vapor, and other gases that can cause deterioration of the contents and permeate the packaging material, in order to prevent deterioration of the contents and maintain their functions and properties. Gas barrier films, which use a metal foil such as aluminum as a gas barrier layer that is less affected by temperature, humidity, and the like, are known as packaging materials with gas barrier properties.

[0003] Another known gas barrier film configuration is one in which an inorganic oxide film such as silicon oxide, aluminum oxide, magnesium oxide, or tin oxide is formed on a base film made of a polymer material by vacuum deposition, sputtering, or the like (see, for example, Patent Documents 1 and 2). These gas barrier films are transparent and have the ability to block gases such as oxygen and water vapor.

[0004] These gas barrier films are considered suitable as packaging materials, possessing both transparency and gas barrier properties that cannot be obtained with metal foils, etc., and films deposited with silicon oxide are particularly widely used as food packaging films. Furthermore, when silicon oxide is used as a deposition material and deposited by a heating method, the film formation rate is extremely fast, and productivity can be improved.

[0005] Gas barrier films containing other metal oxides are known to have a higher gas barrier property than gas barrier films containing vapor-deposited silicon oxide. For example, Patent Document 3 proposes a vapor-deposited film containing a small amount of tin oxide added to a silicon oxide film, which can suppress the occurrence of the splash phenomenon that causes pinholes in the vapor-deposited film and maintain high gas barrier properties. In this vapor-deposited film, the ratio of the number of tin (Sn) to silicon (Si) atoms (Sn / Si) is set to 0.03 to 0.15. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-296036 [Patent Document 2] Japanese Patent Application Publication No. 6-016848 [Patent Document 3] Patent No. 6163776 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the gas barrier film using the vapor-deposited film disclosed in Patent Document 3 has a refractive index of about 1.45 to 1.49 at a wavelength of 550 nm, which is lower than the refractive index of 1.50 to 1.60 of the general resin used as the base. Therefore, depending on the film thickness, light reflection occurs at specific wavelengths, resulting in poor appearance, and there is room for improvement, mainly in terms of optical properties.

[0008] In view of the above circumstances, an object of the present invention is to provide a gas barrier film that has both good gas barrier properties and good optical properties. [Means for solving the problem]

[0009] The present invention is a substrate layer and a Si substrate on one or both sides of the substrate layer. x Sn y O (1-x-y)and a gas barrier layer which is a vapor-deposited film formed by vapor deposition as a film. In this gas barrier film, the surface of the gas barrier layer measured by X-ray photoelectron spectroscopy has a ratio of oxygen to the sum of silicon and tin (O / (Si+Sn)) greater than 1.00 and less than 1.70, a ratio of tin to silicon (Sn / Si) greater than 0.15 and less than 5.00, and a ratio (metallic Sn / Sn) of the area of the Sn3d5 / 2 peak among the metallic Sn peaks representing metallic bonds to the area of the metallic Sn peak in the Sn3d5 / 2 peak, which is 0.05 or more and 0.70 or less. [Effects of the Invention]

[0010] According to the present invention, a gas barrier film that combines good gas barrier properties with good optical properties can be provided. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view of a gas barrier film according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing an example of a manufacturing apparatus for the gas barrier film. [Figure 3] FIG. 2 is a schematic cross-sectional view of a gas barrier film according to a second embodiment of the present invention. [Figure 4] FIG. 2 is a schematic cross-sectional view showing a modified example of the gas barrier film. DETAILED DESCRIPTION OF THE INVENTION

[0012] A first embodiment of the present invention will be described below with reference to FIGS. 1 is a schematic cross-sectional view of a gas barrier film 1 according to this embodiment. The gas barrier film 1 includes a base layer 10 and a gas barrier layer 20 provided on one surface of the base layer 10.

[0013] The base layer 10 is formed of a synthetic resin. There are no particular limitations on the material of the base layer 10, and various known materials can be used. Specific examples include polyolefins (polyethylene, polypropylene, etc.), polyesters (polyethylene terephthalate, polyethylene naphthalate, etc.), polyimides, polyamides (nylon-6, nylon-66, etc.), polystyrene, ethylene vinyl alcohol, polyvinyl chloride, polyimide, polyvinyl alcohol, polycarbonate, polyether sulfone, acrylic, and celluloses (triacetyl cellulose, diacetyl cellulose, etc.). In practice, it is preferable to select an appropriate material depending on the application and required physical properties. For packaging to protect contents that are extremely sensitive to moisture, such as electronic components and optical components, it is preferable to use materials that themselves have high gas barrier properties, such as polyethylene naphthalate, polyimides, and polyether sulfone.

[0014] There are no particular limitations on the thickness of the base layer 10, and it can be about 9 μm to 300 μm, taking into consideration the application, etc. A base layer 10 with a thickness within this range has appropriate flexibility and can be wound into a roll, making it easy to handle.

[0015] The base material layer 10 may be in the form of a continuous material or a sheet material, but a continuous material is preferably used. The longitudinal length of the continuous base material layer 10 is not particularly limited, but a resin film of, for example, 10 m or more is preferably used. The upper limit of the length is not limited, and it may be, for example, about 10 km.

[0016] The surface of the substrate layer 10 may contain additives such as antistatic agents, ultraviolet absorbers, plasticizers, and slip agents as needed. Furthermore, to improve adhesion, the surface of the substrate layer 10 may be subjected to physical treatments such as corona treatment, flame treatment, plasma treatment, and adhesion-enhancing treatment, or chemical treatment / modification treatments such as treatment with an acid or alkali chemical solution. The surface of the substrate layer 10 contributes to the density in the initial growth stage of vacuum film deposition when forming a gas barrier layer, and from this perspective, it is preferable that the surface be as smooth as possible.

[0017] The gas barrier layer 20 plays a major role in the gas barrier properties exhibited by the gas barrier film 1, and is a film made of an inorganic oxide containing at least silicon (Si), tin (Sn), and oxygen (O).

[0018] When the gas barrier layer 20 according to this embodiment does not contain any metal elements other than silicon (Si) and tin (Sn), the ratio (O / (Si+Sn)) of the total amount of silicon (Si) and tin (Sn) to oxygen (O) on the surface of the gas barrier layer 20 measured by X-ray photoelectron spectroscopy (XPS) is: The range of 1.00<(O / (Si+Sn))<1.70 is preferred, 1.20<(O / (Si+Sn))<1.70 is more preferable, It is particularly preferred that 1.40<(O / (Si+Sn))<1.70. If the element composition ratio (O / (Si+Sn)) is less than 1.00, the transparency of the gas barrier layer decreases, and if it is 1.7 or more, sufficient gas barrier properties cannot be obtained.

[0019] The ratio (Sn / Si) of tin (Sn) to silicon (Si) on the surface of the gas barrier layer 20 measured by XPS was: The range of 0.15<(Sn / Si)<5.00 is preferred, 0.15<(Sn / Si)<3.00 is more preferable, It is particularly preferable that 0.15<(Sn / Si)<1.00. By setting the element composition ratio (Sn / Si) within the above range, the refractive index of the gas barrier layer 20 can be made similar to the refractive index of 1.50 to 1.60 of the general resin used as the base, thereby achieving both good gas barrier properties and good optical characteristics.

[0020] When the surface of the gas barrier layer 20 according to this embodiment is measured by XPS, a metallic Sn peak representing a metallic bond containing tin is present. The ratio of the area of the Sn3d5 / 2 peak detected on the surface of the gas barrier layer 20 to the area of the metallic Sn peak in the Sn3d5 / 2 peak (metallic Sn / Sn) is: The range of 0.05≦(metal Sn / Sn)≦0.70 is preferred, 0.05≦(metal Sn / Sn)≦0.60 is more preferable, It is particularly preferable that 0.05≦(metallic Sn / Sn)≦0.50. If the peak area ratio (metallic Sn / Sn) of the Sn3d5 / 2 peak is less than 0.05, the effect of improving the barrier properties due to the inclusion of metallic Sn cannot be obtained, and if it exceeds 1.00, the transparency of the gas barrier layer decreases. In general X-ray photoelectron spectroscopy (XPS), sputter etching using argon (Ar) ions is sometimes used for analysis of the interior of the film, but this can damage the bonds between metal elements and oxygen, making it difficult to accurately obtain the element composition ratio and peak area ratio. For this reason, in the present invention, the values are defined using measurements taken on the surface of the gas barrier layer 20.

[0021] There are no limitations on the method for forming the gas barrier layer 20, and known film-forming methods such as vacuum deposition, ion plating, sputtering, and plasma-enhanced chemical vapor deposition (PECVD) can be used. However, vacuum deposition is particularly preferred due to its superior productivity. Materials heating methods for vacuum deposition include resistance heating, high-frequency induction heating, and electron beam heating. Furthermore, combining a plasma-assisted method or an ion-beam-assisted method can result in a dense gas barrier layer 20, improving its barrier properties. The gas barrier layer 20 formed by the vacuum deposition method has the advantage of easily achieving both gas barrier properties and stretchability. In particular, in packaging applications, external factors such as bending and pulling during processing into packaging materials and impacts during transportation can cause cracks in the gas barrier layer 20, significantly reducing the gas barrier properties, so stretchability is required. Because films formed by the vacuum deposition method are formed via relatively large island structures during the film growth process, they are slightly less dense than those formed by other formation methods such as sputtering, but they have excellent stretchability. In particular, when forming a film made of an inorganic oxide containing tin (Sn), a denser continuous film is more likely to be formed than a film made of an inorganic oxide containing only silicon (Si) and oxygen (O), but on the other hand, the gas barrier properties are more likely to deteriorate due to insufficient elasticity. By forming the inorganic oxide film containing tin by vacuum deposition, the balance between density and elasticity can be controlled. In other words, from the viewpoint of achieving both gas barrier properties and stability, it is preferable to use vacuum deposition as the method for forming the gas barrier layer 20 according to this embodiment.

[0022] The gas barrier layer 20 may contain at least one metal element (A) in addition to silicon (Si) and tin (Sn). The metal element (A) is not particularly limited, and examples thereof include aluminum (Al), silicon (Si), calcium (Ca), scandium (Sc), titanium (Ti), vanadium (V), zinc (Zn), gallium (Ga), germanium (Ge), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), indium (In), tin (Sn), barium (Ba), hafnium (Hf), tungsten (W), tantalum (Ta), and bismuth (Bi). Among these, magnesium (Mg), aluminum (Al), gallium (Ga), tungsten (W), molybdenum (Mo), indium (In), and bismuth (Bi) are preferred because they provide good gas barrier properties and transparency when an oxide film is formed. More preferably, the metal element (A) is magnesium (Mg), aluminum (Al), or tungsten (W). The metal element (A) may be a single element or a combination of multiple elements. The gas barrier layer 20 may contain one or more metal elements (A) in addition to silicon (Si) and tin (Sn), thereby improving the gas barrier properties with the substrate layer 10, improving temperature and humidity durability, and adjusting the refractive index.

[0023] The thickness of the gas barrier layer 20 varies depending on the configuration and film-forming method used, but can generally be set appropriately within the range of 1 to 200 nm. If the thickness of the gas barrier layer 20 is less than 1 nm, a uniform film may not be obtained or the film thickness may be insufficient, and the gas barrier layer may not fully function. If the thickness of the gas barrier layer 20 exceeds 200 nm, external factors such as bending or pulling may cause cracks after film formation, resulting in a loss of barrier properties. The thickness is preferably within the range of 5 to 150 nm, and more preferably within the range of 10 to 120 nm.

[0024] 2 is a schematic diagram showing an example of a gas barrier film manufacturing apparatus according to an embodiment of the present invention. For manufacturing, a film-forming apparatus 100 is used, which includes a vacuum film-forming chamber 40 and an unwinding / winding chamber 50 in which an unwinding roll 42 is disposed. A plastic film 41 that will become the base layer 10 is set on a winding roll 42. The plastic film 41 pulled out from the winding roll 42 passes through a film-forming roll 43 exposed inside the film-forming chamber 40, and is then taken up by a take-up roll 44. A vapor deposition material 45 for forming the gas barrier layer 20 is set inside the film-forming chamber 40, and an electron beam gun 46 is installed as a vapor deposition means. The vapor deposition material 45 is heated by the electron beam and becomes vapor deposition particles 47, which are vapor-deposited on the plastic film. In this way, the gas barrier layer 20 is formed on the plastic film 41.

[0025] 2, electron beam evaporation using an electron beam gun 46 is shown as a method for heating the evaporation material 45, but resistance heating or high-frequency induction heating may also be used to heat and evaporate the evaporation material 45. The resistance heating may be a method in which a crucible filled with the material is directly resistance heated, or another method may also be used.

[0026] The manufacturing apparatus for the gas barrier layer vapor-deposited film is not limited to this form, and if necessary, a plasma pretreatment device may be installed in the unwinding / winding chamber, or a reactive gas introduction device may be installed in the film-forming chamber. There are also no particular limitations on the arrangement of the rolls.

[0027] In this embodiment, the following modifications are also possible. Gas barrier layers are provided on both sides of the base layer 10. In this case, the two gas barrier layers may be the same or different. Plasma treatment is performed on the substrate layer 10, and the gas barrier layer 20 is then laminated on the plasma-treated surface, thereby improving the adhesion and gas barrier properties between the substrate layer 10 and the gas barrier layer 20. The plasma treatment of the substrate layer 10 can be performed by various known plasma treatments such as RIE (Reactive Ion Etching), corona treatment, hollow anode plasma treatment, and planar plasma treatment, as well as various known surface treatments such as ozone treatment and ion beam treatment, which have the same effect as plasma treatment. Known discharge gases such as argon, oxygen, nitrogen, and helium can be used for the plasma treatment.

[0028] A second embodiment of the present invention will be described with reference to Fig. 3. In the following description, components common to those already described will be assigned the same reference numerals and redundant description will be omitted.

[0029] 3 is a schematic cross-sectional view of a gas barrier film 2 according to this embodiment. The gas barrier film 2 further includes an overcoat layer 30 provided on the gas barrier layer 20.

[0030] The overcoat layer 30 is a layer containing an organic polymer resin, and has the function of protecting the gas barrier layer 20 and preventing cracks from occurring due to friction or bending.

[0031] Various known gas barrier films can also be used as the overcoat layer 30. In this case, the barrier properties of the gas barrier film as a whole can be further improved. The overcoat layer 30 is obtained, for example, by forming a coating film made of a coating agent on the gas barrier layer 20 by a wet coating method and drying the coating film. In this specification, the term "coating film" refers to a wet film, and the term "film" refers to a dry film.

[0032] The overcoat layer 30 may be a film containing at least one of a metal alkoxide, its hydrolysate, or its reaction product, and a water-soluble polymer (hereinafter, this may be referred to as an "organic-inorganic composite film.") It is preferable that the overcoat layer 30 further contains at least one of a silane coupling agent and its hydrolysate.

[0033] Examples of metal alkoxides and their hydrolysates contained in the organic-inorganic composite film include those represented by the general formula M(OR)n, such as tetraethoxysilane [Si(OC2H5)4] and triisopropoxyaluminum [Al(OC3H7)3], and their hydrolysates. One of these may be contained alone, or two or more may be contained in combination.

[0034] The total content of at least one of a metal alkoxide and its hydrolysate, or its reaction product in the organic-inorganic composite film can be, for example, 40 to 70 mass%. From the viewpoint of further improving gas barrier properties, the lower limit of the total content of at least one of a metal alkoxide and its hydrolysate, or its reaction product in the organic-inorganic composite film can be 50 mass%. From the same viewpoint, the upper limit of the total content of at least one of a metal alkoxide and its hydrolysate, or its reaction product in the organic-inorganic composite film can be 65 mass%.

[0035] The water-soluble polymer contained in the organic-inorganic composite film is not particularly limited, and examples thereof include polyvinyl alcohol-based polymers, acrylic polyol-based polymers, and polysaccharides such as starch, methyl cellulose, and carboxymethyl cellulose. From the viewpoint of further improving gas barrier properties, it is preferable to include a polyvinyl alcohol-based polymer. The number-average molecular weight of the water-soluble polymer can be, for example, 40,000 to 180,000.

[0036] A water-soluble polymer such as polyvinyl alcohol can be obtained by, for example, saponifying (including partial saponification) polyvinyl acetate. This water-soluble polymer may have several tens of percent or only a few percent of acetate groups remaining.

[0037] The content of the water-soluble polymer in the organic-inorganic composite film can be, for example, 15 to 50 mass %. If the content of the water-soluble polymer is 20 to 45 mass %, the gas barrier properties of the organic-inorganic composite film can be further improved, which is preferable.

[0038] Silane coupling agents and their hydrolysates contained in the organic-inorganic composite film include silane coupling agents having organic functional groups. Examples of such silane coupling agents and their hydrolysates include ethyltrimethoxysilane, vinyltrimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, and their hydrolysates. One of these may be contained alone, or two or more may be contained in combination.

[0039] At least one of the silane coupling agent and its hydrolysate preferably has an epoxy group as an organic functional group. Examples of silane coupling agents having an epoxy group include γ-glycidoxypropyltrimethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. The silane coupling agent having an epoxy group and its hydrolysate may have an organic functional group other than the epoxy group, such as a vinyl group, an amino group, a methacryl group, or a ureyl group.

[0040] A silane coupling agent having an organic functional group and its hydrolysate can further improve the gas barrier properties of the overcoat layer 30 and the adhesion to the gas barrier layer 20 through interaction between the organic functional group and the hydroxyl group of the water-soluble polymer. In particular, the adhesion between the overcoat layer 30 and the gas barrier layer 20 can be improved through interaction between the epoxy group of the silane coupling agent and its hydrolysate and the hydroxyl group of the polyvinyl alcohol.

[0041] The total content of the silane coupling agent and its hydrolysate or at least one of its reaction products in the organic-inorganic composite film can be, for example, 1 to 15 mass %. If the total content of the silane coupling agent and its hydrolysate or at least one of its reaction products is 2 to 12 mass %, the gas barrier properties of the organic-inorganic composite film can be further improved, which is preferable.

[0042] The thickness of the overcoat layer 30 can be set according to the required gas barrier properties, and can be, for example, 0.05 to 5 μm. The thickness of the overcoat layer 30 is preferably 0.05 to 1 μm, and more preferably 0.1 to 0.5 μm. If the thickness of the overcoat layer 30 is 0.05 μm or more, sufficient oxygen barrier properties are likely to be obtained. If the thickness of the overcoat layer 30 is 1 μm or less, it is easy to form a uniform coated surface, and drying load and production costs can be reduced.

[0043] The gas barrier film having the above-described organic-inorganic composite coating as the overcoat layer 30 maintains excellent gas barrier properties even after undergoing boiling treatment or retort sterilization treatment.

[0044] In the gas barrier films according to the above-described embodiments, an undercoat layer 15 may be further provided between the base layer 10 and the gas barrier layer 20, as in the modified example shown in Fig. 4. That is, Fig. 4 shows a modified gas barrier film 2A according to the second embodiment, but the same modifications may be made to the first embodiment shown in Fig. 1. Furthermore, a pair of an undercoat layer 15 and a gas barrier layer 20 may be provided on both sides of the base layer 10.

[0045] The undercoat layer 15 is provided on the base material layer 10 to increase adhesion between the base material layer 10 and the gas barrier layer 20, prevent peeling of the gas barrier layer 20, and protect the gas barrier layer 20 from mechanical damage such as scratches and abrasions. The material for the undercoat layer 15 is not particularly limited, but examples thereof include thermosetting resins, thermoplastic resins, ultraviolet-curable resins, and electron beam-curable resins.

[0046] Examples of thermosetting resins that form the undercoat layer 15 include thermosetting urethane resins made of acrylic polyol resins and isocyanate prepolymers, phenolic resins, urea melamine resins, epoxy resins, unsaturated polyester resins, silicone resins, etc. Among these, by forming the undercoat layer 15 using a composite of an acrylic polyol resin containing a hydroxy group and an isocyanate compound having at least two NCO groups in the molecule, the adhesion between the base material layer 10 and the gas barrier layer 20 can be improved.

[0047] Acrylic polyol resins are polymeric compounds obtained by polymerizing (meth)acrylic acid derivative monomers or polymeric compounds obtained by copolymerizing (meth)acrylic acid derivative monomers with other monomers, and have hydroxy groups at the terminals and side chains, and react with the NCO groups of isocyanate compounds. (Meth)acrylic acid derivative monomers have hydroxy groups at the terminals and side chains. Examples of (meth)acrylic acid derivative monomers include hydroxyethyl (meth)acrylate and hydroxybutyl (meth)acrylate.

[0048] The above-mentioned other monomers can be copolymerized with (meth)acrylic acid derivative monomers having hydroxy groups at their terminals and side chains. Examples of the above-mentioned other monomers include (meth)acrylic acid derivative monomers having an alkyl group at their side chains, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and t-butyl (meth)acrylate; (meth)acrylic acid derivative monomers having a carboxy group at their side chains, such as (meth)acrylic acid; and (meth)acrylic acid derivative monomers having an aromatic ring or cyclic structure at their side chains, such as benzyl (meth)acrylate and cyclohexyl (meth)acrylate. Other than the (meth)acrylic acid derivative monomers, styrene monomers, cyclohexyl maleimide monomers, and phenyl maleimide monomers are also possible. The above-mentioned other monomers may themselves have hydroxy groups at their terminals and side chains.

[0049] The acrylic polyol resin is preferably a polymer compound obtained by polymerizing a (meth)acrylic acid derivative monomer having a carboxy group in the side chain, such as (meth)acrylic acid. When forming the undercoat layer 15, a gas barrier laminate film with higher water vapor barrier properties can be obtained by forming it using a composite of an acrylic polyol resin obtained by polymerizing a monomer having a carboxy group and an isocyanate compound.

[0050] The hydroxyl group-containing acrylic polyol resin that can be used for the undercoat layer 15 is not particularly limited, but preferably has a hydroxyl group value of 50 mg KOH / g or more and 250 mg KOH / g or less. Here, the hydroxyl group value (mg KOH / g) is an index of the amount of hydroxyl groups in the acrylic polyol resin, and indicates the number of mg of potassium hydroxide required to acetylate the hydroxyl groups per gram of acrylic polyol resin. The weight-average molecular weight of the acrylic polyol resin is not particularly limited, but is preferably 3,000 or more and 200,000 or less. It is particularly preferably 5,000 or more and 100,000 or less. It is even more preferably 5,000 or more and 40,000 or less.

[0051] The isocyanate compound used has two or more NCO groups in its molecule. Examples of monomeric isocyanates include aromatic isocyanates such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylene diisocyanate (XDI), and tetramethylxylylene diisocyanate (TMXDI), and aliphatic isocyanates such as hexamethylene diisocyanate (HDI), bisisocyanate methylcyclohexane (H6XDI), isophorone diisocyanate (IPDI), and dicyclohexylmethane diisocyanate (H12MDI). Polymers or derivatives of these monomeric isocyanates can also be used. Examples include trimer nurate types, adduct types reacted with 1,1,1-trimethylolpropane, and biuret types reacted with biuret.

[0052] The isocyanate compound can be arbitrarily selected from the above-mentioned isocyanate compounds or their polymers and derivatives, and one or more of them can be used in combination.

[0053] An example of the undercoat layer 15 is formed by applying a solution consisting of a composite of the above-mentioned acrylic polyol resin and the above-mentioned isocyanate compound and a solvent onto the substrate layer 10, followed by reactive curing. The equivalent ratio (NCO / OH) of the NCO groups of the isocyanate compound to the hydroxy groups of the acrylic polyol resin is preferably 0.3 or more and 2.5 or less. The solvent used here may be any solvent that dissolves the above-mentioned acrylic polyol resin and the isocyanate compound. Examples of solvents include methyl acetate, ethyl acetate, butyl acetate, cyclohexanone, acetone, methyl ethyl ketone, dioxolane, and tetrahydrofuran. In practice, these solvents may be used alone or in combination of two or more.

[0054] The thermoplastic resin forming the undercoat layer 15 may be appropriately selected from polyols having two or more hydroxy groups, such as acrylic polyols, polyester polyols, polycarbonate polyols, polyether polyols, polycaprolactone polyols, and epoxy polyols; polyvinyl resins such as polyvinyl acetate and polyvinyl chloride; polyvinylidene chloride resins; polystyrene resins; polyethylene resins; polypropylene resins; and polyurethane resins. These may also be mixed in any ratio. The hydroxyl value of the polyol is not particularly limited, but is preferably 10 mgKOH / g or more and 250 mgKOH / g or less.

[0055] The UV-curable or electron beam-curable resin forming the undercoat layer 15 preferably contains, but is not limited to, an organic polymer resin having a hydroxyl value in the range of 10 to 100 mgKOH / g. The organic polymer resin preferably contains, but is not limited to, an acid value in the range of 10 to 100 mgKOH / g. Here, the acid value (mgKOH / g) refers to the number of milligrams of potassium hydroxide required to neutralize the free fatty acids, resin acids, etc. contained in 1 g of sample. The organic polymer resin preferably contains at least a thermoplastic resin. If the hydroxyl value or acid value is less than 10 mgKOH / g, the chemical bonding strength between the functional groups and the surface of the gas barrier layer 20 is weakened, tending to reduce adhesion to the gas barrier layer 20. If the hydroxyl value or acid value exceeds 100 mgKOH / g, precipitates containing hydroxyl groups produced by decomposition of the undercoat layer 15 during durability tests such as a moist heat resistance test tend to inhibit adhesion between the undercoat layer 15 and the gas barrier layer 20.

[0056] Monomers that can be used in the ultraviolet-curable resin or electron beam-curable resin that forms the undercoat layer 15 include monofunctional monomers such as ethyl(meth)acrylate, ethylhexyl(meth)acrylate, styrene, methylstyrene, and N-vinylpyrrolidone, as well as polyfunctional monomers such as trimethylolpropane(meth)acrylate, hexanediol(meth)acrylate, tripropylene glycol di(meth)acrylate, diethylene glycol (meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and neopentyl glycol (meth)acrylate. Oligomers that can be used in these ultraviolet-curable resins or electron beam-curable resins include urethane acrylate, epoxy acrylate, and polyester acrylate.

[0057] When two or more types of organic polymer resins selected from thermosetting resins, thermoplastic resins, ultraviolet curable resins, and electron beam curable resins are used in combination as the organic polymer resins forming the undercoat layer 15, the blending ratio thereof is not particularly limited.

[0058] The undercoat layer 15 may further contain additives other than the organic polymer resin, as needed, such as antioxidants, weathering agents, heat stabilizers, lubricants, nucleating agents, ultraviolet absorbers, plasticizers, antistatic agents, colorants, fillers, surfactants, and silane coupling agents.

[0059] The thickness of the undercoat layer 15 is preferably 0.05 μm or more and 10.0 μm or less. It is particularly preferably 0.05 μm or more and 5.0 μm or less. If the thickness is thinner than 0.05 μm, the adhesion between the base layer 10 and the gas barrier layer 20 will be insufficient. If the thickness is thicker than 10.0 μm, the influence of internal stress will be greater, the gas barrier layer 20 will not be laminated neatly, the barrier properties will be insufficient, and the transparency and coating accuracy will also be insufficient.

[0060] The undercoat layer 15 can be formed by a conventional coating method. Examples of well-known methods that can be used include dipping, roll coating, gravure coating, reverse coating, air knife coating, comma coating, die coating, screen printing, spray coating, gravure offset, and organic vapor deposition. The drying method can be one or a combination of two or more heat application methods, such as hot air drying, heat roll drying, high frequency irradiation, infrared irradiation, UV irradiation, and electron beam irradiation. Alternatively, a film previously coated on another resin substrate by the above-mentioned formation method can be transferred to the substrate layer 10 by a transfer method such as adhesive transfer, thermal transfer, or UV transfer.

[0061] The gas barrier film according to each embodiment of the present invention will be further described using examples and comparative examples. The technical scope of the present invention is not limited solely by the specific content of the examples and comparative examples.

[0062] Example 1 A PET film with a thickness of 12 μm was used as the base layer. In a film-forming chamber, a mixture of SiO and SnO was evaporated by adjusting the ratio so that the element composition ratio (Sn / Si) of the evaporation material was 0.20, and Si was deposited on the first surface 10a of the base layer 10 by electron beam evaporation. x Sn y O (1-x-y) A gas barrier layer 20 (thickness: 40 nm) made of a film was formed. Si x Sn y O (1-x-y) The surface of the gas barrier layer 20 made of a film was measured by X-ray photoelectron spectroscopy (XPS) using an AlKα X-ray source and an analyzer transmission energy of 10 eV, and the results showed that (O / (Si+Sn)) was 1.50, (Sn / Si) was 0.20, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.22. In this manner, a gas barrier film according to Example 1 was produced.

[0063] Example 2 The gas barrier film of Example 2 was produced in the same manner as in Example 1, except that a mixed material of Si, SiO2, and Sn was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.16. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.05, (Sn / Si) was 0.16, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.50.

[0064] Example 3 A gas barrier film according to Example 3 was produced in the same manner as in Example 1, except that a mixed material of SiO and SnO was used, the ratio of which was adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.30, and the film thickness was 20 nm. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.40, (Sn / Si) was 0.30, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.15.

[0065] Example 4 The gas barrier film of Example 4 was produced in the same manner as in Example 1, except that a mixed material of Si, SiO2, and SnO2 was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.35, and the film thickness was 30 nm. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.30, (Sn / Si) was 0.35, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.30.

[0066] Example 5 A gas barrier film according to Example 5 was produced in the same manner as in Example 1, except that a mixed material of SiO and SnO was used, the ratio of which was adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.45, and the film thickness was 50 nm. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.42, (Sn / Si) was 0.45, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.11.

[0067] Example 6 A gas barrier film according to Example 6 was produced in the same manner as in Example 1, except that a mixed material of SiO and SnO was used, the ratio of which was adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.50, and the film thickness was 60 nm. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.55, (Sn / Si) was 0.50, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.18.

[0068] Example 7 The gas barrier film of Example 7 was produced using the same procedure as in Example 1, except that a mixed material of Si, SiO2, and SnO2 was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 1.00. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.51, (Sn / Si) was 1.00, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.25.

[0069] Example 8 The gas barrier film of Example 8 was produced using the same procedure as in Example 1, except that a mixed material of Si, SiO2, and SnO2 was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.40. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.65, (Sn / Si) was 0.40, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.05.

[0070] Example 9 A 12 μm-thick PET film was used as the substrate layer, and a mixed solution of acrylic polyol and isocyanate was applied onto the substrate layer by gravure coating and dried to form an undercoat layer with a thickness of 0.2 μm. A gas barrier layer 20 was formed on the undercoat layer in the same manner as in Example 1, thereby producing a gas barrier film according to Example 9. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results showed that (O / (Si+Sn)) was 1.50, (Sn / Si) was 0.20, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.20.

[0071] Example 10 A coating agent prepared by mixing the following (1) liquid and (2) liquid in a weight ratio of 6:4 was applied onto the gas barrier layer 20 of the gas barrier film of Example 1 by gravure coating and dried to form an overcoat layer with a thickness of 0.4 μm. (1) Solution: 10.4 g of tetraethoxysilane was mixed with 89.6 g of hydrochloric acid (0.1 N), and the mixture was stirred for 30 minutes to hydrolyze the solution, resulting in a solid content of 3 wt% (SiO2 equivalent). (2) Liquid: 3 wt% polyvinyl alcohol solution in water / isopropyl alcohol (water:isopropyl alcohol weight ratio 90:10) In this manner, a gas barrier film according to Example 10 was produced.

[0072] Example 11 Onto the gas barrier layer 20 of the gas barrier film of Example 8, a coating agent with a solid content of 5 wt % was applied by gravure coating, which was a mixture of an aqueous solution of polyvinyl alcohol, a hydrolyzed solution of tetraethoxysilane, and a hydrolyzed solution of 1,3,5-tris(3-trimethoxysilylpropyl)isocyanurate silane coupling agent, so that the solid content weight ratio after drying was 30:60:10, and then dried to form an overcoat layer with a thickness of 0.4 μm. In this manner, a gas barrier film according to Example 11 was produced.

[0073] (Comparative Example 1) A gas barrier film according to Comparative Example 1 was produced using the same procedure as in Example 1, except that a mixed material of Si, SiO2, and Sn was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.07. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film had an (O / (Si+Sn)) of 1.90, an (Sn / Si) of 0.07, and a peak area ratio (metallic Sn / Sn) of 0.50 in the Sn3d5 / 2 peak.

[0074] (Comparative Example 2) A gas barrier film according to Comparative Example 2 was produced using the same procedure as in Example 1, except that a mixed material of Si, SiO2, and Sn was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.06. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.50, (Sn / Si) was 0.06, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.80.

[0075] (Comparative Example 3) A gas barrier film according to Comparative Example 3 was produced in the same manner as in Example 1, except that a mixed material of Si, SiO2, and Sn was used, with the ratio adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.18. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.90, (Sn / Si) was 0.18, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.70.

[0076] Comparative Example 4 Oxygen is supplied into the deposition chamber, and the pressure (total pressure) in the deposition chamber is 10 -2 The gas barrier film of Comparative Example 4 was produced in the same manner as Comparative Example 1, except that the gas barrier layer was formed using a mixed material of Si, SiO2, and SnO2, the ratio of which was adjusted so that the elemental composition ratio (Sn / Si) of the vapor deposition material was 0.20, in an oxygen atmosphere with the flow rate adjusted to be in the Pa range. Si x Sn y O (1-x-y) The gas barrier layer 20 made of the film was measured by X-ray photoelectron spectroscopy (XPS) as described in Example 1, and the results were that (O / (Si+Sn)) was 1.60, (Sn / Si) was 0.20, and the peak area ratio (metallic Sn / Sn) at the Sn3d5 / 2 peak was 0.03.

[0077] (Comparative Example 5) A gas barrier film according to Comparative Example 5 was produced in the same manner as in Example 1, except that a SiO material containing no tin was used. Comparative Example 5 did not contain tin, so XPS analysis was omitted.

[0078] The laminates according to the examples and comparative examples were evaluated as follows. (XPS analysis of gas barrier layer) For each example of gas barrier film, the film composition of the gas barrier layer 20 was measured using X-ray photoelectron spectroscopy (JPS-9010MX manufactured by JEOL Ltd.). AlKα was used as the X-ray source, and the analyzer transmission energy was set to 10 eV. To avoid the influence of noise, each narrow spectrum was repeatedly scanned and integrated 30 or more times. (Refractive index measurement of gas barrier layer) For the gas barrier film according to each example, the refractive index of the gas barrier layer 20 was measured using an ellipsometer (VUV-VASE) manufactured by J.A. Woollam Corporation. (Water vapor barrier performance evaluation) The gas barrier films of each example were measured using a water vapor transmission rate measuring device manufactured by Mocon (product name: PERMATRAN3 / 34G, measurement conditions: 40°C-90% RH, unit: g / (m 2 The water vapor transmission rate (WVTR) was evaluated using the FTIR (TfL) method. The results are shown in Table 1.

[0079] [Table 1]

[0080] In all of the gas barrier films according to the examples, the (O / (Si+Sn)) on the surface of the gas barrier layer 20 measured by X-ray photoelectron spectroscopy (XPS) was 1.0<(O / (Si+Sn))<1.7, (Sn / Si) was 0.15<(Sn / Si)<10.00, and the peak area ratio (metal Sn / Sn) at the Sn3d5 / 2 peak was 0.05≦(metal Sn / Sn)≦1.00, which was within the range of claim 1. The gas barrier films according to the examples all have a WVTR of 2.0 g / (m 2 ·day) and the refractive index at a wavelength of 550 nm was in the range of 1.50 to 1.60, achieving both good gas barrier properties and good optical properties.

[0081] On the other hand, the gas barrier films according to Comparative Examples 1 and 2 had a (Sn / Si) ratio of 0.15 or less on the surface of the gas barrier layer 20 measured by X-ray photoelectron spectroscopy (XPS). The barrier films according to these comparative examples had good gas barrier properties, but had a refractive index of less than 1.50 at a wavelength of 550 nm. In the gas barrier film according to Comparative Example 3, the (O / (Si+Sn)) of the surface of the gas barrier layer 20 measured by X-ray photoelectron spectroscopy (XPS) exceeded 1.70. The gas barrier film according to this comparative example had inferior gas barrier properties compared to the gas barrier films according to the examples. In the gas barrier film according to Comparative Example 4, the peak area ratio (metallic Sn / Sn) of the Sn3d5 / 2 peak on the surface of the gas barrier layer 20 measured by X-ray photoelectron spectroscopy (XPS) was less than 0.05. The gas barrier film according to this comparative example had inferior gas barrier properties compared to the gas barrier films according to the examples. The barrier film according to Comparative Example 5 has a gas barrier layer 20 of SiO x The gas barrier layer 20 is a Si film. x Sn y O (1-x-y) The gas barrier properties and optical properties were both inferior to those of the gas barrier films of the Examples, which were films. As described above, none of the gas barrier films according to the comparative examples achieved both gas barrier properties and optical properties. In addition, in the gas barrier films according to the Examples and Comparative Examples, no cracks were observed in the gas barrier layer after 5% stretching, and the gas barrier layer had good stretchability.

[0082] The above describes each embodiment and example of the present invention, but the specific configuration is not limited to these embodiments, and includes modifications and combinations of configurations within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0083] 1, 2, 2A gas barrier film 10 Base material layer 15 Undercoat layer 20 Gas barrier layer 30 Overcoat layer 40 Deposition chamber 41 Plastic Film 42 Unwinding roll 43 Coating roll 44 Winding roll 45 Evaporation materials 46 Electron Beam Gun 47 Vapor deposition particles 50 Unwinding and winding room 100 Film deposition equipment

Claims

1. a substrate layer; The substrate layer has one or both sides formed of Si ｘ Sn ｙ O （１－ｘ－ｙ） a gas barrier layer that is a vapor-deposited film; Equipped with The surface of the gas barrier layer measured by X-ray photoelectron spectroscopy is the ratio of the sum of silicon and tin to oxygen (O / (Si+Sn)) is greater than 1.00 and less than 1.70; a tin to silicon ratio (Sn / Si) greater than 0.15 and less than 5.00; Among the metal Sn peaks representing metallic bonds, the ratio of the area of the Sn3d5 / 2 peak to the area of the metal Sn peak in the Sn3d5 / 2 peak (metal Sn / Sn) is 0.05 or more and 0.70 or less; Gas barrier film.

2. the refractive index of the gas barrier layer at a wavelength of 550 nm is 1.50 or more and 1.80 or less; The gas barrier film according to claim 1 .

3. The thickness of the gas barrier layer is 1 nm or more and 200 nm or less. The gas barrier film according to claim 1 .

4. Further comprising an overcoat layer formed on the gas barrier layer. The gas barrier film according to claim 1 .

5. the overcoat layer contains at least one of a metal alkoxide, a hydrolyzate of a metal alkoxide, a reaction product of a metal alkoxide, and a reaction product of a hydrolyzate of a metal alkoxide, and a water-soluble polymer; The gas barrier film according to claim 4.

6. the overcoat layer contains at least one of a silane coupling agent, a hydrolysate of a silane coupling agent, a reaction product of a silane coupling agent, and a reaction product of a hydrolysate of a silane coupling agent; The gas barrier film according to claim 4.

7. an undercoat layer provided between the substrate layer and the gas barrier layer; The undercoat layer contains at least one of a thermosetting resin, a thermoplastic resin, an ultraviolet curable resin, and an electron beam curable resin. The gas barrier film according to claim 1 .

8. an undercoat layer provided between the substrate layer and the gas barrier layer; the undercoat layer is made of a cured product of a composition containing an acrylic polyol resin and an isocyanate compound; The gas barrier film according to claim 1 .

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