Gas barrier laminate and method for producing the same

Abstract

To provide a transparent gas barrier laminate which has good water vapor barrier properties and uses a resin substrate, and a method for manufacturing the gas barrier laminate.SOLUTION: The gas barrier laminate includes a resin substrate and a transparent oxide film layer containing tungsten (W) formed on one surface or both surfaces of the resin substrate and further includes an undercoat layer between the resin substrate and the transparent oxide film layer. The undercoat layer is a layer comprising a cured product of a composition containing an acrylic resin having an organic acid group. The composition further contains a polyisocyanate. The acrylic resin is an acrylic polyol resin. The gas barrier laminate has a water vapor permeability of 0.05 g / (m2 day) or less in measurement conditions of 40°C and 90% R.H.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gas barrier laminate using a resin substrate and a method for producing the same. [Background technology]

[0002] Gas barrier laminates are laminates that have the property of preventing the penetration of oxygen, water vapor, etc. (gas barrier properties), and are widely used in a variety of fields that require the blocking of various gases, such as packaging for precision electronic components, electronics materials, food, pharmaceuticals, etc.

[0003] The required gas barrier properties vary depending on the application, but generally, sealing films for displays such as organic electroluminescence (EL) elements and electronic paper require a gas barrier property of 0.05 g / (m 2 In recent years, there has been an increasing demand for even higher levels of water vapor barrier properties. These films also require transparency.

[0004] In recent years, in fields such as organic electroluminescence (EL) and electronic paper, there has been a trend toward using resins instead of glass as substrates for reasons such as flexibility, breakage prevention, and weight reduction. However, resin substrates have poor gas barrier properties against oxygen and water vapor, which can lead to problems with deterioration of the elements and electronic components to be sealed.

[0005] Therefore, various products have been developed to achieve high gas barrier properties and transparency using resin substrates, and in recent years, many gas barrier laminates have been proposed in which metal oxide films such as silicon oxide and aluminum oxide, and oxynitride films of various metals are provided on a resin substrate at a nanoscale.

[0006] Furthermore, physical film formation methods such as induction heating, resistance heating, electron beam evaporation, and sputtering are being investigated as methods for producing gas barrier laminates, as they are easy to apply to large areas and roll-to-roll processes.

[0007] In order to achieve higher gas barrier properties, it is necessary to form a dense gas barrier layer made of an inorganic compound, and dense inorganic compound films can generally be easily produced by sputtering.

[0008] For example, Patent Document 1 below describes a gas barrier film with high water vapor barrier performance and good transparency. In the gas barrier film described in Patent Document 1, a silicon (Si) oxide film serving as a barrier layer is formed on one surface of a resin substrate by RF magnetron sputtering.

[0009] However, in order to meet the higher standards of water vapor barrier properties that have been demanded in recent years, further improvements are required. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Patent No. 3971638 Summary of the Invention [Problem to be solved by the invention]

[0011] Therefore, the present invention provides a transparent gas barrier film using a resin substrate that has good water vapor barrier properties. The object of the present invention is to provide an adhesive laminate and a method for producing the same. [Means for solving the problem]

[0012] The gas barrier laminate according to the present invention comprises a resin substrate and a transparent oxide film layer containing tungsten (W) formed on one or both sides of the resin substrate, and further comprises an undercoat layer between the resin substrate and the transparent oxide film layer, the undercoat layer being a layer made of a cured product of a composition containing an acrylic resin having an organic acid group, the composition further containing polyisocyanate, the acrylic resin being an acrylic polyol resin, and having a water vapor transmission rate of 0.05 g / (m) at measurement conditions of 40°C and 90% RH.2 ·day) or less.

[0013] The method for producing a gas barrier laminate according to the present invention includes a step of forming a transparent oxide film layer using a magnetron sputtering device. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a transparent gas barrier laminate using a resin substrate and having good water vapor barrier properties, and a method for producing the same. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view of a gas barrier laminate according to a first embodiment of the present invention. [Figure 2] FIG. 3 is a cross-sectional view of a gas barrier laminate according to a second embodiment of the present invention. [Figure 3] FIG. 3 is a cross-sectional view of a gas barrier laminate according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] First Embodiment A first embodiment of the present invention will be described below with reference to the drawings.

[0017] As shown in Fig. 1, the gas barrier laminate according to this embodiment comprises a resin substrate 11 and a transparent oxide film layer 13 formed on one side of the resin substrate 11. In practice, the transparent oxide film layer 13 may be laminated on both sides of the resin substrate 11. In the following description, the transparent oxide film layer formed (laminated) on the resin substrate 11 and the transparent oxide film layer 13 are synonymous.

[0018] (Resin substrate) The material of the resin substrate 11 is not particularly limited, and known materials can be used. Examples include, but are not limited to, 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 desirable to select an appropriate material depending on the application and required physical properties. For packaging that protects contents that are extremely sensitive to moisture, such as electronic components and optical components, it is desirable to use a resin substrate 11 that itself has high gas barrier properties, such as polyethylene naphthalate, polyimides, or polyether sulfone, but this is not a limitation.

[0019] Furthermore, the thickness of the resin substrate 11 is not limited, but a thickness of about 12 μm to 300 μm is easily used depending on the application. A resin substrate 11 having a thickness within this range is preferred because it is flexible and can be wound into a roll.

[0020] The resin substrate 11 may be in the form of a continuous material or a sheet material, but a continuous resin substrate 11 is preferably used. The longitudinal length of the continuous resin substrate 11 is not particularly limited, but a continuous 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.

[0021] The surface of the resin substrate 11 may contain additives such as antistatic agents, ultraviolet absorbers, plasticizers, and slip agents as needed. Furthermore, to improve adhesion, the surface of the resin substrate 11 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 resin substrate 11 contributes to the density in the initial growth stage of vacuum film formation, and is therefore desirably smooth.

[0022] (Transparent oxide film layer) The transparent oxide film layer 13 is a transparent oxide film containing tungsten (W) that is provided to impart gas barrier properties to the entire gas barrier laminate.

[0023] The transparent oxide film layer 13 is formed so that the ratio of the number of oxygen (O) atoms to the number of tungsten (W) atoms (O / W) is 2.0 or more and 3.0 or less, at least on the surface of the transparent oxide film layer. Considering transparency and gas barrier properties, the ratio of the number of oxygen (O) atoms to the number of tungsten (W) atoms (O / W) is more preferably 2.5 or more and 3.0 or less. A conventionally known method can be used to determine whether the transparent oxide film layer 13 is within the above composition range, and evaluation can be performed using results obtained with an analytical device such as an XPS (X-ray photoelectron spectrometer). Analytical devices such as an XPS (X-ray photoelectron spectrometer) sometimes use sputter etching with argon (Ar) ions to analyze the interior of the film. However, transparent oxide film layers containing tungsten (W) are reduced, making it impossible to obtain the correct ratio of the number of tungsten (W) atoms to the number of oxygen (O) atoms (O / W). Therefore, it is preferable to analyze the surface.

[0024] The transparent oxide film layer 13 is formed to be amorphous. By forming an amorphous film, the film does not have grain boundaries that occur in polycrystalline films, and therefore the permeation paths of gas molecules can be reduced. Whether the transparent oxide film layer 13 is amorphous can be determined by a conventionally known method. For example, it can be evaluated by whether or not a crystalline diffraction peak is present in an X-ray diffraction pattern obtained by an analytical device such as an XRD (X-ray diffractometer).

[0025] Furthermore, the transparent oxide film layer 13 may contain one or more metal elements (A) in addition to tungsten (W). The metal element (A) is not particularly limited, and examples thereof include magnesium (Mg), 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), and tantalum (Ta). Among these, aluminum (Al), silicon (Si), zinc (Zn), molybdenum (Mo), tin (Sn), and hafnium (Hf) are preferred because they provide good gas barrier properties and transparency when an oxide film is formed. The metal element (A) may be a single element or a combination of multiple elements. When the transparent oxide film layer 13 contains one or more metal elements (A) in addition to tungsten (W), it is possible to improve adhesion to the resin substrate 11, improve durability against temperature and humidity, and adjust the refractive index n.

[0026] When the transparent oxide film layer 13 contains one or more metal elements (A) in addition to tungsten (W), it is formed so that the ratio of the number of tungsten (W) atoms to the total number of tungsten (W) atoms and the metal element (A) atoms (W / (W+A)) is 0.5 or more and less than 1.0, and the ratio of the number of oxygen (O) atoms to the total number of tungsten (W) atoms and the metal element (A) atoms (O / (W+A)) is 1.50 or more and less than 3.00. In particular, when the metal element (A) is silicon (Si), it is preferable to form the transparent oxide film layer 13 so that the ratio of the number of tungsten (W) atoms to the total number of metal element (A) atoms (W / (W+A)) is 0.9 or more and less than 1.0. Setting the film composition of the transparent oxide film layer 13 within the above ranges can impart high transparency and high gas barrier properties. A conventionally known method can be used to determine whether the transparent oxide film layer 13 is within the above composition range, and for example, evaluation can be performed using the results obtained with an analytical device such as an XPS (X-ray photoelectron spectrometer).

[0027] Furthermore, by setting the film composition of the transparent oxide film layer 13 within the above range, the refractive index n becomes 1.5 or more and 2.3 or less, and a refractive index n close to that of the resin substrate 11 to a refractive index n higher than that of the resin substrate 11 can be obtained. Alternatively, the necessary refractive index n can be selected depending on the application of the gas barrier laminate. The refractive index of the transparent oxide film layer 13 can be measured and evaluated by measuring the refractive index of a film having the same composition as the transparent oxide film layer 13 using a refractometer (ellipsometer).

[0028] The thickness of the transparent oxide film layer 13 is preferably 5 nm or more and 500 nm or less. If it is less than 5 nm, the transparent oxide film layer 13 will not be able to cover the entire resin substrate 11, and sufficient gas barrier properties will not be obtained. If it is more than 500 nm, cracks will be more likely to occur, and gas barrier properties may be reduced. Furthermore, costs will increase due to an increase in the amount of material used and a longer film formation time, which is not preferable from an economic standpoint. It is preferable that the optical film thickness nd, which is the product of the film thickness d and the refractive index n, is 7 nm or more and 1000 nm or less.

[0029] (Method for forming a transparent oxide film layer) The transparent oxide film layer 13 can be formed using any conventional film-forming method capable of forming a metal oxide film. Examples of film-forming methods include physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, and ion plating, and chemical vapor deposition (CVD) methods such as thermal chemical vapor deposition, plasma-enhanced chemical vapor deposition, and atomic layer deposition. However, various sputtering methods are preferred because they can easily form dense films with high gas barrier properties. Among sputtering methods, magnetron sputtering is preferred because it can achieve a high film-forming rate and minimize damage to the resin substrate during film formation. As for the power supply method for generating plasma, sputtering is preferred because it can periodically apply voltage to electrodes. Furthermore, it is preferable to use a sputtering method using a magnetron sputtering device in which a voltage can be applied periodically to an electrode and, during off-times, pulses of opposite polarity (pulse voltage) are applied to the applied voltage, or a magnetron sputtering device in which two electrodes are positioned in parallel, and a voltage of alternating positive and negative polarity can be applied to each electrode, with each electrode alternately serving as a cathode and an anode. Alternatively, a sputtering method using a magnetron sputtering device equipped with a cylindrical electrode having a rotating mechanism may be used. Furthermore, when forming a transparent oxide layer using these sputtering methods, it is preferable to set the film formation pressure in the range of 0.05 Pa to 1.00 Pa. By using the above-mentioned sputtering method and setting the film formation pressure, an amorphous film with high density and few defects can be obtained.

[0030] When forming the transparent oxide film layer 13 using various sputtering methods, a target made of metallic tungsten is used, and the transparent oxide film layer 13 is formed by a reactive sputtering method using oxygen gas. Alternatively, a target made of tungsten oxide (WO3) may be used. Furthermore, the target described above may further contain one or more metal elements (A) in addition to tungsten (W).

[0031] The gas barrier laminate according to this embodiment is constructed by laminating the above-described transparent oxide film layer 13 on a resin substrate 11. This allows the gas barrier laminate to have a water vapor transmission rate of 0.05 g / (m) under measurement conditions of 40°C and 90% RH. 2 ·day) or less. In addition, by forming the transparent oxide film layer 13 into a dense film, the helium permeability under the measurement conditions of 40°C and 0% RH can be reduced to 300 cc / (m 2 ·day·atm) or less. Furthermore, by using the sputtering method using the magnetron sputtering device described above, it is possible to manufacture a gas barrier laminate having a dense transparent oxide film layer 13. Therefore, according to this embodiment, a gas barrier laminate having good gas barrier properties and a method for manufacturing the same can be realized.

[0032] Second Embodiment A second embodiment of the present invention will now be described.

[0033] The gas barrier laminate according to this embodiment, like the gas barrier laminate shown in Fig. 2, further comprises an undercoat layer 12 provided between the resin substrate 11 and the transparent oxide film layer 13 of the gas barrier laminate shown in Fig. 1. Alternatively, the gas barrier laminate may have a configuration in which the undercoat layer 12 and the transparent oxide film layer 13 are sequentially laminated on both sides of the resin substrate 11.

[0034] The undercoat layer 12 is provided on the resin substrate 11 to improve adhesion between the resin substrate 11 and the transparent oxide film layer 13, prevent peeling of the transparent oxide film layer 13, and protect the transparent oxide film layer 13 from mechanical damage such as scratches and abrasions. The material for the undercoat layer 12 is not particularly limited, but examples thereof include thermosetting resins, thermoplastic resins, ultraviolet-curable resins, and electron beam-curable resins.

[0035] Examples of the thermosetting resin that forms the undercoat layer 12 include a thermosetting urethane resin made of an acrylic polyol resin and an isocyanate prepolymer, a phenol resin, a urea melamine resin, an epoxy resin, an unsaturated polyester resin, a silicone resin, etc. Among these, by forming the undercoat layer 12 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 resin substrate 11 and the transparent oxide film layer 13 can be improved.

[0036] 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.

[0037] The above-mentioned other monomers can be copolymerized with (meth)acrylic acid derivative monomers having hydroxy groups at the terminals and side chains. Examples of the above-mentioned other monomers include (meth)acrylic acid derivative monomers having an alkyl group at the side chain, 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 the side chain, such as (meth)acrylic acid; and (meth)acrylic acid derivative monomers having an aromatic ring or cyclic structure at the side chain, 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.

[0038] 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 12, a composite of an acrylic polyol resin obtained by polymerizing a monomer having a carboxy group and an isocyanate compound can be used to obtain a gas barrier laminate film with higher water vapor barrier properties.

[0039] There are no particular limitations on the hydroxyl group-containing acrylic polyol resin that can be used for the undercoat layer 12, but it is desirable that the hydroxyl group value be 50 mgKOH / g or more and 250 mgKOH / g or less. Here, the hydroxyl group value (mgKOH / 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 in 1 g of the acrylic polyol resin. The weight average molecular weight of the acrylic polyol resin is not particularly limited, but specifically, it is preferably 3,000 or more and 200,000 or less, particularly preferably 5,000 or more and 100,000 or less, and even more preferably 5,000 or more and 40,000 or less.

[0040] 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.

[0041] The isocyanate compound may be selected from the above-mentioned isocyanate compounds or their polymers and derivatives, and one or more of them may be used in combination.

[0042] One example of the undercoat layer 12 is formed by applying a solution consisting of a composite of the acrylic polyol resin and the isocyanate compound and a solvent onto the resin substrate 11, 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 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.

[0043] The thermoplastic resin forming the undercoat layer 12 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.

[0044] The UV-curable resin or electron beam-curable resin forming the undercoat layer 12 is preferably an organic polymer resin having a hydroxyl value in the range of 10 to 100 mgKOH / g, but is not particularly limited thereto. The organic polymer resin is preferably an organic polymer resin having an acid value in the range of 10 to 100 mgKOH / g, but is not particularly limited thereto. 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 transparent oxide film layer 13 is weakened, and adhesion to the transparent oxide film layer 13 tends to be reduced. If the hydroxyl group value or acid value exceeds 100 mgKOH / g, precipitates containing hydroxyl groups produced by decomposition of the undercoat layer 12 during durability tests such as moist heat resistance tests tend to inhibit adhesion between the undercoat layer 12 and the transparent oxide film layer 13.

[0045] Monomers that can be used in the UV-curable resin or electron beam-curable resin that forms the undercoat layer 12 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 UV-curable resins or electron beam-curable resins include urethane acrylate, epoxy acrylate, and polyester acrylate.

[0046] When two or more 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 12, the compounding ratio is not particularly limited.

[0047] The undercoat layer 12 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.

[0048] The thickness of the undercoat layer 12 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 resin substrate 11 and the transparent oxide film layer 13 becomes insufficient. If the thickness is thicker than 10.0 μm, the influence of internal stress becomes greater, the transparent oxide film layer 13 is not laminated neatly, the barrier properties are not fully exhibited, and further, the transparency and coating accuracy become insufficient.

[0049] The undercoat layer 12 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 resin substrate 11 using a transfer method such as adhesive transfer, thermal transfer, or UV transfer.

[0050] <Third embodiment> A third embodiment of the present invention will now be described.

[0051] The gas barrier laminate according to this embodiment, like the gas barrier laminate shown in Fig. 3, further comprises an overcoat layer 14 provided on the transparent oxide film layer 13 of the gas barrier laminate shown in Fig. 2. The same effect can also be obtained by providing an overcoat layer 14 on the transparent oxide film layer 13 of the gas barrier laminate shown in Fig. 1.

[0052] The overcoat layer 14 is a layer containing an organic polymer resin, and is provided to protect the transparent oxide film layer 13 and prevent cracks from occurring due to friction or bending.

[0053] The organic polymer resin contained in the overcoat layer 14 can be appropriately selected, and for example, one or more types selected from thermosetting resins, thermoplastic resins, ultraviolet curable resins, and electron beam curable resins can be used. The ratio is not particularly limited and can be set appropriately.

[0054] Examples of thermosetting resins that can form the overcoat layer 14 include thermosetting urethane resins made of acrylic polyol resins and isocyanate prepolymers, phenolic resins, urea melamine resins, epoxy resins, unsaturated polyester resins, and silicone resins. Among these, the overcoat layer 14 can be formed using a composite of an acrylic polyol resin containing a hydroxyl group and an isocyanate compound having at least two NCO groups in the molecule, thereby improving adhesion between the overcoat layer 14 and the transparent oxide film layer 13.

[0055] 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.

[0056] 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.

[0057] 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 12, a composite of an acrylic polyol resin obtained by polymerizing a monomer having a carboxy group and an isocyanate compound can be used to obtain a gas barrier laminate film with higher water vapor barrier properties.

[0058] The hydroxyl group-containing acrylic polyol resin of the overcoat layer 14 is not particularly limited, but preferably has a hydroxyl group value of 50 mgKOH / g or more and 250 mgKOH / g or less. 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.

[0059] An isocyanate compound is one that 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. For example, trimerized N-isocyanates are also usable. There are various types, such as the ester type, the adduct type reacted with 1,1,1-trimethylolpropane, and the biuret type reacted with biuret.

[0060] The isocyanate compound may be selected arbitrarily from the above-mentioned isocyanate compounds or their polymers and derivatives, and one or more kinds may be used in combination.

[0061] The overcoat layer 14 is formed, for example, by applying a solution composed of a composite of the acrylic polyol resin and the isocyanate compound and a solvent onto the resin substrate 11, 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 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.

[0062] In addition to the above, the thermosetting resin forming the overcoat layer 14 preferably contains at least one selected from the group consisting of a water-soluble polymer having a hydroxyl group, and an alkoxysilane and its hydrolysate.

[0063] Preferred water-soluble polymers containing hydroxyl groups are polyvinyl alcohol, polycarboxylic acid, starch, and celluloses. In particular, polyvinyl alcohol (hereinafter referred to as PVA) exhibits excellent gas barrier properties when used in the coating agent of the present invention. Because PVA is the polymer with the highest number of hydroxyl groups in its monomer unit, it forms very strong hydrogen bonds with the hydroxyl groups of organosilicon compounds after hydrolysis. The PVA referred to here is generally obtained by saponifying polyvinyl acetate, and includes so-called partially saponified PVA, in which several tens of percent of acetate groups remain, and fully saponified PVA, in which only a few percent of acetate groups remain. PVA molecular weights vary widely, ranging from 300 to several thousand degrees of polymerization, and the use of any molecular weight will not affect its effectiveness. However, high-molecular-weight PVA with a high degree of saponification and polymerization is generally preferred due to its high water resistance.

[0064] Examples of alkoxysilanes that can be used include tetraethoxysilane, tetramethoxysilane, tetrapropoxysilane, methyltriethoxysilane, and methyltrimethoxysilane. Examples of hydrolysis products of alkoxysilanes include those prepared by dissolving an alkoxysilane in an alcohol such as methanol, adding an aqueous solution of an acid such as hydrochloric acid to the resulting solution, and then subjecting the solution to a hydrolysis reaction. Through the hydrolysis reaction, the alkoxy groups bonded to silicon atoms become hydroxy groups, and the hydroxy groups undergo dehydration condensation to form siloxane bonds, resulting in the formation of a dense and strong network polymerized coating. This allows for the production of an overcoat layer 14 that is excellent in heat resistance, water resistance, humidity resistance, flex resistance, and stretch resistance.

[0065] A silane coupling agent may be added to improve adhesion to the transparent oxide film layer 13. Examples of silane coupling agents include those having an epoxy group such as 3-glycidoxypropyltrimethoxysilane, those having an amino group such as 3-aminopropyltrimethoxysilane, those having a mercapto group such as 3-mercaptopropyltrimethoxysilane, and those having an NCO group such as 3-isocyanatepropyltriethoxysilane, and these silane coupling agents can be used alone or in combination of two or more.

[0066] The thermoplastic resin forming the overcoat layer 14 is, for example, acrylic polyol. The polyol may be selected from polyols having two or more hydroxy groups, such as 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. In particular, a polyol having a glass transition temperature of 20°C to 100°C and two or more hydroxy groups is preferably included. By maintaining the glass transition temperature within the above range, adhesion to the transparent oxide film layer 13 can be improved when the overcoat layer 14 is formed by thermal transfer. Furthermore, defects in the transparent oxide film layer 13 due to thermal transfer can be prevented, improving thermal transferability. The hydroxyl value of the polyol is not particularly limited, but is preferably 10 mgKOH / g to 250 mgKOH / g from the viewpoints of adhesion and water resistance.

[0067] The UV-curable resin or electron beam-curable resin forming the overcoat layer 14 is preferably an organic polymer resin having, but not limited to, a hydroxyl value in the range of 10 to 100 mgKOH / g. The organic polymer resin is preferably an organic polymer resin having, but not limited to, a resin having, at least an acid value in the range of 10 to 100 mgKOH / g. 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 group and the surface of the transparent oxide film layer 13 weakens, tending to reduce adhesion to the transparent oxide film layer 13. If the hydroxyl value or acid value is greater than 100 mgKOH / g, precipitates containing hydroxyl groups produced by decomposition of the overcoat layer 14 during durability tests such as a moist heat resistance test tend to inhibit adhesion between the overcoat layer 14 and the transparent oxide film layer 13.

[0068] Monomers that can be used in the UV-curable resin or electron beam-curable resin that forms the overcoat layer 14 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 the UV-curable resin or electron beam-curable resin include urethane acrylate, epoxy acrylate, and polyester acrylate.

[0069] When two or more 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 overcoat layer 14, the compounding ratio thereof is not particularly limited.

[0070] The overcoat layer 14 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.

[0071] The thickness of the overcoat layer 14 is not particularly limited and can be set as appropriate. Preferably, it is 0.05 μm or more and 10.0 μm or less. If it is thinner than 0.05 μm, the protection of the transparent oxide film layer 13 will be insufficient, and if it is thicker than 10.0 μm, the influence of internal stress will be greater, causing cracks.

[0072] As with the undercoat layer 12, the overcoat layer 14 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. Drying methods can include 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 a separate resin substrate by the above-described formation method can be transferred to the transparent oxide film layer 13 by a transfer method such as adhesive transfer, thermal transfer, or UV transfer. [Example]

[0073] EXAMPLES The gas barrier laminate according to the present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0074] In Example 1, Comparative Examples 1 and 2, a transparent oxide film layer 13 is provided on one side of a resin substrate 11. In Examples 2, 3, 4, 5, 6, 7, 8, 9, and Comparative Examples 3 and 4, an undercoat layer 12 is further provided between the resin substrate 11 and the transparent oxide film layer 13. In Example 3, an overcoat layer 14 is further provided on the transparent oxide film layer 13. That is, Example 1, Comparative Examples 1 and 2 correspond to the gas barrier laminate shown in FIG. 1. Examples 2, 4, 5, 6, 7, 8, 9, and Comparative Examples 3 and 4 correspond to the gas barrier laminate shown in FIG. 2. Example 3 corresponds to the gas barrier laminate shown in FIG. 3.

[0075] Example 1 [Resin substrate placement process] As the resin substrate 11, a biaxially stretched PET film (manufactured by Toray Industries, Inc., product name "Lumirror T60") having a thickness of 50 μm was used.

[0076] [Transparent oxide film layer stacking process] A transparent oxide film layer 13 was formed on one surface of the resin substrate 11 by a sputtering method (referred to as Method A) using a magnetron sputtering device that can periodically apply a voltage to the electrodes and applies a pulse with a different positive or negative polarity from the applied voltage during the off time of the applied voltage. The film formation conditions were a film formation pressure of 0.35 Pa and a power density of 3.3 W / cm. 2 A metal tungsten (W) target was used. A DC power supply was used as a means for applying power to the electrode. A pulse voltage with a frequency of 10 kHz (on time: 95%, off time: 5%, negative voltage applied during on time and positive voltage applied during off time) was applied to the electrode. Argon gas and oxygen gas were used as gases. The target surface was in oxide mode, and the flow rate of the oxygen gas was adjusted so that a transparent oxide film was obtained. A transparent oxide film layer 13 with a thickness of 100 nm was formed, thereby obtaining a gas barrier laminate.

[0077] <Example 2> [Resin substrate placement process] As in Example 1, a biaxially stretched PET film (manufactured by Toray Industries, Inc., product name "Lumirror T60") having a thickness of 50 μm was used as the resin substrate 11.

[0078] [Undercoat layer solution preparation and coating process] The solution for the undercoat layer 12 was an acrylic polyol (weight average molecular weight 10 × 10) obtained by copolymerizing hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) as monomers. 3 ) as the main component, and a 5% methyl ethyl ketone solution was prepared by blending 1 equivalent of an HDI nurate type isocyanate curing agent relative to the amount of hydroxyl groups in the main component. Then, the solution prepared above was applied onto the resin substrate 11, and the thickness after drying was 300 mm. An undercoat layer 12 having a thickness of nm was laminated.

[0079] [Transparent oxide film layer stacking process] Under the same sputtering conditions as in Example 1, a transparent oxide film layer 13 having a thickness of 100 nm was formed on the undercoat layer 12, thereby obtaining a gas barrier laminate.

[0080] Example 3 [Resin substrate placement process] As in Examples 1 and 2, a biaxially stretched PET film having a thickness of 50 μm (manufactured by Toray Industries, Inc., product name "Lumirror T60") was used as the resin substrate 11.

[0081] [Undercoat layer solution preparation and coating process] As in Example 2, an undercoat layer 12 having a thickness of 300 nm after drying was laminated on a resin substrate 11.

[0082] [Transparent oxide film layer stacking process] A transparent oxide film layer 13 having a thickness of 100 nm was formed on the undercoat layer 12 under the same sputtering conditions as in Examples 1 and 2, except that a sintered target of tungsten oxide (WO3) was used.

[0083] [Preparation and coating process of the solution for the overcoat layer] A solution with a solid content of 5 mass % was prepared as a solution for the overcoat layer 14 by mixing a hydrolyzed solution of tetraethoxysilane (TEOS) and an aqueous solution of polyvinyl alcohol (PVA) so that the solid content ratio after drying would be 70:30. Thereafter, the prepared solution was applied onto the transparent oxide film layer 13 by spin coating, and an overcoat layer 14 with a thickness of 300 nm after drying was laminated, thereby obtaining a gas barrier laminate.

[0084] Example 4 The film-forming conditions for the transparent oxide film layer 13 were the same as those in Example 2, except that the flow rate of oxygen gas was adjusted to be lower than those in Examples 1 and 2, to obtain a gas-barrier laminate.

[0085] <Example 5> A gas barrier laminate was obtained in the same manner as in Example 2, except that the transparent oxide film layer 13 was formed by a sputtering method (referred to as Method B) using a magnetron sputtering device in which two electrodes were positioned in parallel, and alternately positive and negative voltages could be applied to each electrode, with each electrode alternately serving as a cathode and an anode. An MF power supply was used as a means for applying power to the two electrodes. A rectangular voltage with a frequency of 40 kHz was applied to the two parallel electrodes. Argon gas and oxygen gas were used as gases. The flow rate of oxygen gas was controlled by detecting the plasma emission intensity and the discharge voltage value so that the state of the target surface was in a transition state, which was a state in the middle of transitioning from the metal mode to the oxide mode. The film formation conditions were a film formation pressure of 0.50 Pa, a power density of 0.50 Pa, and a 3.3W / cm 2 Argon gas and oxygen gas were used as the gases, and the flow rate of the oxygen gas was adjusted so that an oxide film was obtained.

[0086] Example 6 A gas barrier laminate was obtained in the same manner as in Example 2, except that a sputtering method (referred to as Method C) was used to form the transparent oxide film layer 13. The method used was a magnetron sputtering device equipped with two cylindrical electrodes with a rotating mechanism arranged in parallel, capable of applying alternately positive and negative voltages to each electrode, with each electrode alternately serving as a cathode and an anode. A MF power supply was used as a means for applying power to the two electrodes. A frequency of 40 A rectangular voltage of 1000 kHz was applied to two electrodes placed in parallel. Argon gas and oxygen gas were used as gases. The flow rate of oxygen gas was controlled by detecting the plasma emission intensity and the discharge voltage value so that the state of the target surface was in a transition state, which was in the middle of transitioning from metal mode to oxide mode. The deposition conditions were a deposition pressure of 0.3 0 Pa, power density 3.3 W / cm 2 It was decided.

[0087] Example 7 A gas barrier laminate was obtained in the same manner as in Example 2, except that an alloy target of tungsten (W) and silicon (Si) (atomic composition ratio W:Si=90:10) was used.

[0088] Example 8 A gas barrier laminate was obtained in the same manner as in Example 2, except that an alloy target of tungsten (W) and aluminum (Al) (atomic composition ratio W:Al=50:50) was used.

[0089] Example 9 A gas barrier laminate was obtained in the same manner as in Example 2, except that an alloy target of tungsten (W) and tin (Sn) (atomic composition ratio W:Sn=80:20) was used.

[0090] <Comparative Example 1> A gas barrier laminate was obtained in the same manner as in Example 1, except that an alloy target of silicon (Si) and tin (Sn) was used.

[0091] <Comparative Example 2> A gas barrier laminate was obtained in the same manner as in Example 1, except that the flow rate of oxygen gas was adjusted so that the surface of the metal tungsten (W) target was in an intermediate state between the metal mode and the oxide mode.

[0092] <Comparative Example 3> A gas barrier laminate was obtained in the same manner as in Example 2, except that a silicon (Si) target was used.

[0093] <Comparative Example 4> A gas barrier laminate was obtained in the same manner as in Example 2, except that an alloy target of silicon (Si) and tungsten (W) (atomic composition ratio W:Si=25:75) was used.

[0094] <Evaluation and Method> [Measurement of film composition of transparent oxide film layer of gas barrier laminate] The film compositions of the gas barrier laminates produced in Examples 1 to 9 and Comparative Examples 1 to 4 were measured using an X-ray photoelectron spectrometer (JPS-9010MX) manufactured by JEOL Ltd. In this case, the composition of the outermost surface was analyzed to avoid the influence of reduction due to Ar ion etching.

[0095] [Measurement of refractive index of transparent oxide film layer of gas barrier laminate] The refractive index of the gas barrier laminates produced in Examples 1 to 9 and Comparative Examples 1 to 4 was measured using an ellipsometer (VUV-VASE) manufactured by J.A. Woollam.

[0096] [Measurement of gas barrier properties of gas barrier laminate] The gas barrier laminates produced in Examples 1 to 9 and Comparative Examples 1 to 4 were measured using a water vapor transmission rate meter manufactured by MOCON, USA, in accordance with a method in accordance with JIS-K7129. (AQUATRAN-Model II) measured the water vapor transmission rate (g / m) under an environment of 40℃ 90%RH (temperature 40℃, relative humidity 90%). 2 The helium permeability (cc / (m 2 The gas permeability (MPa) was measured at 40°C and 0% RH using a differential pressure method in accordance with JIS K 7126A using a pressure sensor type gas measuring device (Delta Palm DP-2MST) manufactured by Technolox.

[0097] [Measurement results] The measurement results are shown in Table 1 below. [Table 1]

[0098] Comparing Example 1 corresponding to the first embodiment with Comparative Example 1, Example 1, which contains tungsten (W) in the target and transparent oxide film layer 13, exhibited better water vapor permeability and helium permeability than Comparative Example 1, which contains only silicon (Si) and tin (Sn) in the target and transparent oxide film layer 13.

[0099] Furthermore, when Example 1 corresponding to the first embodiment is compared with Comparative Example 2, the target and the transparent oxide film layer 13 in both Example 1 and Comparative Example 2 contain tungsten (W), but Example 1, in which the ratio (O / W) of the number of oxygen (O) atoms to the number of tungsten (W) atoms on the surface of the transparent oxide film layer 13 is 2.0 or more and 3.0 or less, exhibits better values ​​for both water vapor permeability and helium permeability than Comparative Example 2, in which the O / W is less than 2.0.

[0100] Comparing Example 2 and Examples 4 to 9 corresponding to the second embodiment with Comparative Example 3, Examples 2 and Examples 4 to 9, which contain tungsten (W) in the target and transparent oxide film layer 13, exhibited better values ​​for both water vapor permeability and helium permeability than Comparative Example 3, which contains only silicon (Si) in the target and transparent oxide film layer 13.

[0101] In Example 5, the sputtering method was Method B, but similar to Example 2 in which the sputtering method was Method A, good results were obtained in terms of water vapor permeability and helium permeability.

[0102] In Example 6, the sputtering method was Method C, but similar to Example 2 in which the sputtering method was Method A, good results were obtained in terms of water vapor permeability and helium permeability.

[0103] Furthermore, when Examples 7 to 9 corresponding to the second embodiment are compared with Comparative Example 4, all of which contain tungsten (W) and the metal element (A) in the target and the transparent oxide film layer 13, Examples 7 to 9, in which the ratio (W / (W+A)) of the number of tungsten (W) atoms in the transparent oxide film layer 13 to the total number of atoms of tungsten (W) and the metal element (A) is 0.5 or more and less than 1.0, exhibit better values ​​for both water vapor permeability and helium permeability than Comparative Example 4, in which W / (W+A) is less than 0.5.

[0104] In Example 3 corresponding to the third embodiment, a sintered tungsten oxide (WO3) target was used to form the transparent oxide film layer 13, and an overcoat layer was also laminated. However, similar to Example 2 corresponding to the second embodiment, in which a metallic tungsten (W) target was used to form the transparent oxide film layer 13 and no overcoat layer was laminated, good results were obtained for water vapor permeability, helium permeability, and neon permeability.

[0105] Although the embodiments of the present invention have been described in detail above, in reality, the present invention is not limited to the above-described embodiments, and even if modifications are made within the scope of the gist of the present invention, they are included in the present invention. [Industrial Applicability]

[0106] The gas barrier laminate according to the present invention is expected to be particularly suitable for use in fields such as electronic equipment-related materials where high gas barrier properties are required. [Explanation of symbols]

[0107] 11...Resin substrate 12...Undercoat layer 13…Transparent oxide film layer 14...Overcoat layer

Claims

1. A resin substrate and a transparent oxide film layer containing tungsten (W) formed on one or both surfaces of the resin substrate, an undercoat layer is further provided between the resin substrate and the transparent oxide film layer; the undercoat layer is a layer made of a cured product of a composition containing an acrylic resin having an organic acid group, the composition further containing polyisocyanate, and the acrylic resin is an acrylic polyol resin; The water vapor transmission rate at measurement conditions of 40°C and 90% RH is 0.05 g / (m ２ ・day) or less.

2. 2. The gas barrier laminate according to claim 1, wherein the ratio (O / W) of the number of oxygen (O) atoms to the number of tungsten (W) atoms on the surface of the transparent oxide film layer is 2.0 or more and 3.0 or less.

3. 3. The gas barrier laminate according to claim 1, wherein the transparent oxide film layer is amorphous.

4. 4. The gas barrier laminate according to claim 1, wherein the transparent oxide film layer contains at least one metal element (A) other than tungsten (W), and the ratio (W / (W+A)) of the number of tungsten (W) atoms in the transparent oxide film layer to the total number of atoms of tungsten (W) and the metal element (A) is 0.5 or more and less than 1.0, and the ratio (O / (W+A)) of the number of oxygen (O) atoms to the total number of atoms of tungsten (W) and the metal element (A) is 1.5 or more and 3.0 or less.

5. Measurement conditions: Helium permeability at 40°C and 0% RH is 300 cc / (m ２ 5. The gas barrier laminate according to claim 1, wherein the gas barrier density is 1000 kJ / s or less (1000 kJ / s).

6. 6. The gas barrier laminate according to claim 1, further comprising an overcoat layer on the outside of the transparent oxide film layer, the overcoat layer being formed from at least one of a thermosetting resin, a thermoplastic resin, an ultraviolet-curable resin, and an electron beam-curable resin.

7. 7. The gas barrier laminate according to claim 6, wherein the overcoat layer is formed containing a water-soluble polymer having a hydroxy group and at least one selected from the group consisting of alkoxysilanes and hydrolysates thereof.

8. 7. The gas barrier laminate according to claim 6, wherein the overcoat layer is formed from a thermoplastic resin having a glass transition temperature of 20°C or higher and 100°C or lower and containing a polyol having two or more hydroxyl groups.

9. 9. A method for producing the gas barrier laminate according to claim 1, comprising the step of forming the transparent oxide film layer by using a magnetron sputtering device.

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