JP7547732B2 - Gas barrier laminate - Google Patents

Description

The present invention relates to a gas barrier laminate using a resin substrate.

A gas barrier laminate is a laminate that has the property of not allowing oxygen, water vapor, etc. to pass through (gas barrier properties), and is widely used in a variety of fields that require blocking various gases, such as precision electronic parts, electronics materials, and packaging for food and medicine, etc.

The required gas barrier properties vary depending on the application, but generally, it is said that a high water vapor barrier property of 0.01 g/( ^m2 ·day) or less is required for sealing films for displays such as organic electroluminescence (EL) and electronic paper, and in recent years, there has been an increasing demand for even higher levels of water vapor barrier properties. In addition, these films are required to be transparent.

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

For this reason, 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 nanoscale on a resin substrate.

In addition, as a method for producing gas barrier laminates, physical film formation methods such as induction heating, resistance heating, electron beam deposition, and sputtering are being considered because they are easy to use for large-area production and roll-to-roll processing.

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.

In addition, to achieve higher transparency, it is necessary to have low reflection at the interface between the resin substrate and the inorganic compound film and high light transmittance for visible light. For this reason, it is necessary to form an inorganic compound film with a refractive index close to that of the resin substrate.

For example, the following Patent Document 1 describes a transparent resin substrate (gas barrier laminate) that is highly transparent and has high water vapor barrier performance. In this gas barrier laminate, a transparent oxide film that contains tin oxide and silicon (Si) as an additive element in a ratio of 46 atomic % to 63 atomic % relative to the total of Si and Sn, is an amorphous film, and has a refractive index of 1.75 or less at a wavelength of 633 nm, is formed as a gas barrier layer on at least one surface of a resin substrate by a direct current (DC) pulse sputtering method.

However, it is stated that the water vapor transmission rate of the gas barrier laminate is less than 0.01 g/( ^m2 ·day) as measured by the Mocon method in accordance with JIS K7129, and this gas barrier laminate certainly has high water vapor gas barrier properties. However, in order to meet the higher standards of water vapor barrier properties that have been demanded in recent years, further improvement is required.

On the other hand, chemical film formation methods such as PECVD (Plasma Enhanced CVD), Cat-CVD, and ALD (Atomic Layer Deposition) are also being considered as manufacturing methods for other gas barrier laminates, as they are easy to scale up and can be expanded to roll-to-roll.

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 manufactured by the ALD method. In the example described in Patent Document 2, an organic light-emitting polymer (OLED) is formed on a polyester substrate having flexibility and transparency, and a gas barrier layer covering the entire surface and side surface of the light-emitting polymer is formed by the ALD method. Patent Document 2 describes a light-transmitting gas barrier film that can reduce the effects of the above-mentioned defects and defects by such a gas barrier layer, and that can reduce gas permeation by an order of magnitude compared to conventional gas barrier films with a thickness of several tens of nanometers. However, it is known that such atomic layer deposition films are easily scratched on the surface, and the scratches may reach the substrate, easily impairing the gas barrier properties.

In addition, by providing an undercoat layer between the transparent resin substrate and the gas barrier layer made of an inorganic compound, further improvement in gas barrier properties can be achieved. In the example described in Patent Document 3, it is presumed that the surface free energy of the undercoat layer can be kept relatively low by using a specific acrylic resin, so that in the initial growth process when forming the inorganic layer, atoms and particles that become the growth nuclei of the film are more likely to move and diffuse on the surface, and the film quality near the undercoat layer becomes denser, resulting in dramatically improved gas barrier properties. However, in the case of inorganic layer formation by the winding method, problems may occur due to contact with the roller during transport of the laminate after inorganic layer formation, or contact between the plastic substrate and the inorganic layer when winding up the laminate after inorganic layer formation. Furthermore, problems may occur due to external mechanical stress on the laminate as described above when wound on a roll, that is, when transporting or storing the laminate on a roll, or when processing it into a gas barrier film, and the risk of deterioration of gas barrier properties cannot be eliminated.

Patent No. 4788463 JP 2007-090803 A Patent No. 6070194

Therefore, the present invention aims to provide a transparent gas barrier laminate using a resin substrate that has good water vapor barrier properties and whose water vapor barrier properties are not significantly impaired even by external mechanical stress.

One aspect of the present invention for solving the above problems is a gas barrier laminate comprising a resin substrate, an undercoat layer laminated on at least one side of the resin substrate, and a transparent oxide film layer laminated on the undercoat layer, the undercoat layer being made of a cured film of a compound containing at least acryloyl groups and urethane bonds, with the ratio of the number of acryloyl groups to the number of urethane bonds being 1.5 to 5.0, and the undercoat layer being characterized in that the Martens hardness of the undercoat layer is 200 N/ ^mm2 or more, the transparent oxide film layer being a physical vapor deposition film characterized in containing at least silicon (Si) and any one of tin (Sn) and tungsten (W) , the gas barrier laminate being characterized in that the water vapor transmission rate under measurement conditions of 40°C and 90% R.H. is 0.01 g/( ^m2 ·day) or less, and the helium transmission rate under measurement conditions of 40°C and 0% R.H. is 4 cc/( ^m2 ·day·atm) or less.

In the gas barrier laminate according to the present invention, the undercoat layer may have more acryloyl groups than urethane bonds.

In the gas barrier laminate of the present invention, the thickness of the undercoat layer may be 0.05 μm or more and 10 μm or less.

In the gas barrier laminate of the present invention, the transparent oxide film layer may contain at least silicon (Si) and tin (Sn).

In the gas barrier laminate of the present invention, the transparent oxide film layer may contain at least silicon (Si) and tungsten (W).

In the gas barrier laminate according to the present invention, the water vapor transmission rate after an abrasion test (using steel wool #0000, a load of 75 g, one round trip) under measurement conditions of 40° C. and 90% R.H. may be 0.05 g/( ^m2 ·day) or less.

The gas barrier laminate according to the present invention may further have an overcoat layer on the outside of the transparent oxide film layer, and the overcoat layer may be formed from at least one of a thermosetting resin, a thermoplastic resin, an ultraviolet-curable resin, and an electron beam-curable resin.

In addition, the gas barrier laminate according to the present invention may be formed such that the overcoat layer contains at least one selected from the group consisting of a water-soluble polymer having a hydroxyl group, and an alkoxysilane and its hydrolysate.

The present invention provides a transparent gas barrier laminate using a resin substrate that has good water vapor barrier properties and whose water vapor barrier properties are not significantly impaired even by external mechanical stress.

1 is a cross-sectional view of a gas barrier laminate according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view of a gas barrier laminate according to a second embodiment of the present invention.

First Embodiment
A first embodiment of the present invention will be described below with reference to the drawings. As shown in Fig. 1, the gas barrier laminate according to this embodiment comprises a resin substrate 11, an undercoat layer 12 formed on one side of the resin substrate 11, and a transparent oxide film layer 13 formed on one side of the undercoat layer 12. In practice, the undercoat layer 12 and the transparent oxide film layer 13 may be laminated on both sides of the resin substrate 11.

(Resin substrate)
The material of the resin substrate 11 is not particularly limited, and known materials can be used. For example, 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, polyethersulfone, acrylic, celluloses (triacetyl cellulose, diacetyl cellulose, etc.), etc. can be mentioned, but are not particularly limited to these. In practice, it is desirable to select appropriately depending on the application and required physical properties, and for packaging that protects contents that are extremely averse 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, and polyethersulfone, but is not limited to these examples.

The thickness of the resin substrate 11 is not limited, but a thickness of about 12 μm to 300 μm is suitable 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.

The resin substrate 11 may be in the form of a long material or a sheet material, but a long resin substrate 11 is preferably used. The longitudinal length of the long resin substrate 11 is not particularly limited, but a long film of, for example, 10 m or more is preferably used. There is no upper limit to the length, and it may be, for example, about 10 km.

The surface of the resin substrate 11 may contain additives such as antistatic agents, UV absorbers, plasticizers, and slip agents, if necessary. Furthermore, in order to improve adhesion, the surface of the resin substrate 11 may be subjected to physical treatments such as corona treatment, frame treatment, plasma treatment, and adhesion-improving treatment, or chemical treatments such as chemical treatments with acids or alkalis. The surface of the resin substrate 11 contributes to the denseness in the initial growth stage of vacuum film formation, and is desirably smooth.

The undercoat layer 12 is provided on the resin substrate 11 to increase the 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 of the undercoat layer 12 is not particularly limited, but may be a thermosetting resin, a thermoplastic resin, an ultraviolet-curable resin, an electron beam-curable resin, or the like.

The thermosetting resin that forms the undercoat layer 12 can be a thermosetting urethane resin made of an acrylic polyol resin and an isocyanate prepolymer. By forming the undercoat layer 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, the adhesion between the resin substrate 11 and the transparent oxide film layer 13 can be improved.

An acrylic polyol resin is a polymer compound obtained by polymerizing a (meth)acrylic acid derivative monomer, or a polymer compound obtained by copolymerizing a (meth)acrylic acid derivative monomer with another monomer, which has hydroxy groups at the end and side chains and reacts with the NCO group of an isocyanate compound. A (meth)acrylic acid derivative monomer has hydroxy groups at the end and side chains. Examples of (meth)acrylic acid derivative monomers include hydroxyethyl (meth)acrylate and hydroxybutyl (meth)acrylate.

The above other monomers can be copolymerized with (meth)acrylic acid derivative monomers having hydroxy groups at the end and in the side chain. Examples of the above other monomers include (meth)acrylic acid derivative monomers having an alkyl group in 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 in the side chain, such as (meth)acrylic acid, and (meth)acrylic acid derivative monomers having an aromatic ring or cyclic structure in the side chain, such as benzyl (meth)acrylate and cyclohexyl (meth)acrylate.

The acrylic polyol resin is preferably a polymeric compound obtained by polymerizing a (meth)acrylic acid derivative monomer having a carboxy group on the side chain, such as (meth)acrylic acid. When forming the undercoat layer 12, a gas barrier laminate film having higher water vapor barrier properties can be obtained by forming the undercoat layer 12 using a composite of an acrylic polyol resin obtained by polymerizing a monomer having a carboxy group and an isocyanate compound.

There are no particular limitations on the hydroxyl group-containing acrylic polyol resin that can be used in the undercoat layer 12, but it is desirable for the hydroxyl group value to 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. In addition, there are no particular limitations on the weight average molecular weight of the acrylic polyol resin, but specifically, it is preferably 3,000 or more and 200,000 or less. In particular, it is preferably 5,000 or more and 100,000 or less. Furthermore, it is more preferably 5,000 or more and 40,000 or less.

An isocyanate compound 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, there are trimer nurate types, adduct types reacted with 1,1,1-trimethylolpropane, and biuret types reacted with biuret.

The isocyanate compound may be selected from the above-mentioned isocyanate compounds or their polymers and derivatives, and one or a combination of two or more types may be used.

An example of the undercoat layer 12 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 resin substrate 11 and reacting and curing it. The equivalent ratio (NCO/OH) of the NCO group of the isocyanate compound to the hydroxy group 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 the solvent include methyl acetate, ethyl acetate, butyl acetate, cyclohexanone, acetone, methyl ethyl ketone, dioxolane, tetrahydrofuran, etc. In practice, these solvents can be used alone or in combination of two or more.

The thermoplastic resin forming the undercoat layer 12 may be, for example, a mixture of acrylic polyol and polyurethane resin in any ratio. The hydroxyl value of the acrylic polyol is not particularly limited, but is preferably 10 mgKOH/g or more and 250 mgKOH/g or less.

As the ultraviolet-curable resin or electron beam-curable resin forming the undercoat layer 12, it is desirable to include at least a resin having a hydroxyl value in the range of 10 to 100 mgKOH/g as an organic polymer resin, although it is not particularly limited thereto. In addition, it is desirable to include at least a resin having an acid value in the range of 10 to 100 mgKOH/g as an organic polymer resin, although it is not particularly limited thereto. Here, the acid value (mgKOH/g) indicates the number of mg of potassium hydroxide required to neutralize the free fatty acid, resin acid, etc. contained in 1 g of sample. It is also desirable to include at least a thermoplastic resin as an organic polymer 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 becomes weak, and the adhesion to the transparent oxide film layer 13 tends to be low. If the hydroxyl 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 a moist heat resistance test tend to inhibit adhesion between the undercoat layer 12 and the transparent oxide film layer 13.

Monomers that can be used in the ultraviolet-curable resin or electron beam-curable resin that forms the undercoat layer 12 include monofunctional monomers such as ethyl (meth)acrylate and ethylhexyl (meth)acrylate, 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. Examples of oligomers that can be used in this ultraviolet-curable resin or electron beam-curable resin include urethane acrylate.

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 12, the mixing ratio is not particularly limited.

The organic polymer resin forming the undercoat layer 12 contains at least acryloyl groups and urethane bonds. By containing acryloyl groups and urethane bonds, the film quality of the transparent oxide film layer 13 near the undercoat layer becomes dense, and the gas barrier properties become good. Furthermore, it is preferable that there are more acryloyl groups than urethane bonds. With more acryloyl groups, the film becomes harder, and even after the transparent oxide film layer 13 is laminated, it becomes less susceptible to scratches due to external mechanical stress, and therefore the water vapor barrier properties are not significantly impaired.

The undercoat layer 12 has a Martens hardness of 200 N/mm2 or ^more . This is because the hardness of the film is increased for the above-mentioned reasons. Therefore, even after laminating the transparent oxide film layer 13, it is difficult to be scratched by external mechanical stress, and therefore the water vapor barrier property is not significantly impaired. Martens hardness is one of the ways to indicate the hardness of a substance, and can be measured by the nanoindentation method. Martens hardness is a type of scratch hardness, and is expressed as the load when a pyramidal diamond with a facing angle of 90 degrees is used to create a scratch width of 0.01 millimeters on the surface of the sample.

The undercoat layer 12 may further contain additives other than the organic polymer resin as necessary. Examples of additives include antioxidants, weathering agents, heat stabilizers, lubricants, crystal nucleating agents, UV absorbers, plasticizers, antistatic agents, colorants, fillers, surfactants, and silane coupling agents.

The thickness of the undercoat layer 12 is preferably 0.05 μm or more and 10.0 μm or less. In particular, it is preferably 0.05 μm or more and 5.0 μm or less. If it is thinner than 0.05 μm, the adhesion between the resin substrate 11 and the transparent oxide film layer 13 will be insufficient. If it is thicker than 10.0 μm, the effect of internal stress will be large, the transparent oxide film layer 13 will not be laminated neatly, the barrier properties will not be expressed sufficiently, and further, the transparency and coating accuracy will be insufficient.

The undercoat layer 12 can be formed by a conventional coating method. For example, well-known methods such as dipping, roll coating, gravure coating, reverse coating, air knife coating, comma coating, die coating, screen printing, spray coating, gravure offset, and organic deposition can be used. As a drying method, one or more methods of applying heat such as hot air drying, heat roll drying, high frequency irradiation, infrared irradiation, UV irradiation, and electron beam irradiation can be used in combination. In addition, a film that has been coated in advance on another resin substrate by the above forming method can be transferred to the resin substrate 11 by a transfer method such as adhesive transfer, heat transfer, and UV transfer.

(Transparent oxide film layer)
The transparent oxide film layer 13 is a transparent oxide film containing silicon (Si) that is provided to impart gas barrier properties to the entire gas barrier laminate. In addition to silicon (Si), tin (Sn) or tungsten (W) may be contained. It is presumed that the inclusion of an element with a different size from silicon (Si) forms a dense film and improves the water vapor barrier properties, but the details are unclear.

The transparent oxide film layer 13 may further contain at least one element selected from Mg, Al, Ca, Sc, Ti, V, Zn, Ga, Ge, Sr, Y, Zr, Nb, In, Ba, Hf, and Ta in addition to silicon (Si) and tin (Sn) or tungsten (W). By containing at least one element selected from Mg, Al, Ca, Sc, Ti, V, Zn, Ga, Ge, Sr, Y, Zr, Nb, In, Ba, Hf, and Ta in addition to silicon (Si), tin (Sn) or tungsten (W), the gas barrier properties, adhesion to the resin substrate 11, temperature and humidity durability, and refractive index n can be improved. The transparent oxide film layer 13 may further contain nitrogen in addition to the metal element group, and may be a transparent oxynitride film layer.

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 cannot cover the entire resin substrate 11, and sufficient gas barrier properties cannot be obtained. If it exceeds 500 nm, cracks are likely to occur and the gas barrier properties may be reduced. Furthermore, costs increase due to an increase in the amount of material used and a longer film formation time, which is not preferable from an economic point of view. It is preferable that the optical thickness nd, which is expressed by the product of the thickness d and the refractive index n, is 7 nm or more and 1000 nm or less.

The transparent oxide film layer 13 may be a physical vapor deposition film formed by a physical vapor deposition (PVD) method, or may be a chemical vapor deposition film formed by a chemical vapor deposition (CVD) method. In one embodiment, the transparent oxide film layer 13 is preferably a physical vapor deposition film formed by a sputtering method.

The physical vapor deposition film serving as the transparent oxide film layer 13 is formed by deposition using a physical vapor deposition (PVD) method. The PVD method is a method for depositing a thin film of a target substance, such as an inorganic substance, on the surface of a substance in the gas phase using a physical method, such as sputtering (DC sputtering, RF sputtering, ion beam sputtering, magnetron sputtering, etc.), vacuum deposition, and ion plating.

In the sputtering method, a target is placed in a vacuum chamber, and high voltage is applied to cause ionized rare gas elements (usually argon) to collide with the target, dislodging atoms from the target surface and depositing them on the substrate. A reactive sputtering method may also be used in this process, in which nitrogen gas or oxygen gas is passed through the chamber to react the elements dislodged from the target by the argon gas with the nitrogen or oxygen to form an inorganic layer.

(About the sputtering method)
As a means for forming the transparent oxide film layer 13, various sputtering methods can be used. Preferably, a sputtering method using a magnetron sputtering device capable of periodically applying a voltage to an electrode is used. According to this sputtering method, since a voltage is periodically applied, an off time of the voltage application is provided, and the charging of the target surface is eliminated. Therefore, damage to the film caused by arcing can be suppressed, and a high-quality film can be stably formed. Furthermore, preferably, a sputtering method using a magnetron sputtering device capable of periodically applying a voltage to an electrode and applying a pulse of a different polarity from that of the voltage application during the off time of the voltage application is used. According to this sputtering method, an off time of the voltage application is provided, and further, the voltage during the off time is inverted in polarity from that during the application, so that the charging of the target surface is more easily eliminated. Therefore, damage to the film caused by arcing can be more suppressed, and a high-quality film can be stably formed. Also, preferably, a sputtering method using a magnetron sputtering device is used, in which two electrodes are positioned in parallel, and a positive and negative voltages can be applied alternately to each electrode, and each electrode alternately plays the role of a cathode and an anode. In this sputtering method, a target of material is placed on two electrodes installed in a vacuum chamber, and a high voltage is applied to cause an ionized rare gas element (usually argon) to collide with the target, ejecting atoms from the target surface, and the target element is attached to the undercoat layer 12, thereby forming a transparent oxide film layer 13. In this sputtering method, the anode and cathode are alternately switched between the two targets, so that while one target is discharging and forming a film, the other target is weakly charged in the opposite direction, thereby eliminating the charge on the target surface. Therefore, damage to the film caused by arcing can be suppressed, and a high-quality film can be stably formed. At this time, a predetermined amount of oxygen gas is flowed into the chamber, and the element ejected from the target reacts with oxygen to form the transparent oxide film layer 13. Furthermore, at this time, a transparent oxynitride film layer may be formed by flowing nitrogen gas simultaneously with the oxygen gas. The target is made of silicon (Si) and tin (Sn) or tungsten (W). The target may further contain at least one element selected from Mg, Al, Ca, Sc, Ti, V, Zn, Ga, Ge, Sr, Y, Zr, Nb, In, Sn, Ba, Hf, and Ta in addition to silicon (Si), tin (Sn), or tungsten (W).

Even when using a magnetron sputtering device capable of applying a voltage periodically to an electrode, or when using a magnetron sputtering device in which two electrodes are positioned in parallel, and positive and negative voltages can be applied alternately to each electrode, with each electrode alternately serving as a cathode and an anode, the power source for applying the voltage to the electrodes is not particularly specified and may be either alternating current (AC) or DC, but it is preferable to use a DC pulse power source. This is because a pulse wave for the applied voltage waveform is more effective in mitigating charge-up at the anode during off-times of voltage application. The frequency of the DC pulse power source is not particularly limited and can be set as appropriate. It is preferably 1 kHz or more and 100 kHz or less, and more preferably 10 kHz or more and 50 kHz or less.

The chemical vapor deposition film as the transparent oxide film layer 13 is formed by film formation by the chemical vapor deposition (CVD) method. The CVD method is a method in which a raw material gas containing the components of the target thin film is supplied onto a substrate, and a film is deposited by a chemical reaction on the substrate surface or in the gas phase. In addition, there are methods in which plasma is generated for the purpose of activating the chemical reaction, and examples of such methods include known CVD methods such as thermal CVD, catalytic chemical vapor deposition, photo CVD, vacuum plasma CVD, atmospheric pressure plasma CVD, and ALD. Although not particularly limited, it is preferable to apply the plasma CVD method from the viewpoint of film formation speed and processing area. The gas barrier layer obtained by the vacuum plasma CVD method and the plasma CVD method under atmospheric pressure or near atmospheric pressure is preferable because the target compound can be produced by selecting conditions such as the metal compound, which is the raw material (also called raw material), the decomposition gas, the decomposition temperature, and the input power. In addition, the atomic layer deposition film formed by the atomic layer deposition (ALD) method is also preferable because it can form a dense film.

The gas barrier laminate according to this embodiment is constructed by sequentially laminating the above-mentioned undercoat layer 12 and the above-mentioned transparent oxide film layer 13 on a resin substrate 11. This allows the water vapor transmission rate to be 0.01 g/( ^m2 ·day) or less under measurement conditions of 40° C. and 90% R.H. Also, the helium transmission rate to be 4 cc/( ^m2 ·day·atm) or less under measurement conditions of 40° C. and 0% R.H. Therefore, according to this embodiment, a gas barrier laminate having good gas barrier properties can be realized.

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

The gas barrier laminate according to this embodiment is similar to the gas barrier laminate shown in FIG. 2 in that an overcoat layer 14 is further provided on the transparent oxide film layer 13 of the gas barrier laminate shown in FIG. 1.

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 the occurrence of cracks due to rubbing or bending.

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 curing resins, and electron beam curing resins can be used. The proportion of the organic polymer resin in the overcoat layer 14 is not particularly limited and can be set appropriately.

Thermosetting resins that 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, silicone resins, and the like. In particular, 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 the adhesion between the overcoat layer 14 and the transparent oxide film layer 13.

An acrylic polyol resin is a polymer compound obtained by polymerizing a (meth)acrylic acid derivative monomer, or a polymer compound obtained by copolymerizing a (meth)acrylic acid derivative monomer with another monomer, which has hydroxy groups at the end and side chains and reacts with the NCO group of an isocyanate compound. A (meth)acrylic acid derivative monomer has hydroxy groups at the end and side chains. Examples of (meth)acrylic acid derivative monomers include hydroxyethyl (meth)acrylate and hydroxybutyl (meth)acrylate.

The above other monomers can be copolymerized with (meth)acrylic acid derivative monomers having hydroxy groups at the end and at the side chain. Examples of the above 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 a cyclic structure at the side chain, such as benzyl (meth)acrylate and cyclohexyl (meth)acrylate. Other than (meth)acrylic acid derivative monomers, styrene monomers, cyclohexylmaleimide monomers, and phenylmaleimide monomers are possible. The above other monomers may themselves have hydroxy groups at the end and at the side chain.

The acrylic polyol resin is preferably a polymeric compound obtained by polymerizing a (meth)acrylic acid derivative monomer having a carboxy group on the side chain, such as (meth)acrylic acid. When forming the undercoat layer 12, a gas barrier laminate film having higher water vapor barrier properties can be obtained by forming the undercoat layer 12 using a composite of an acrylic polyol resin obtained by polymerizing a monomer having a carboxy group and an isocyanate compound.

The hydroxyl group-containing acrylic polyol resin of the overcoat layer 14 is not particularly limited, but it is desirable that the hydroxyl group value is 50 mgKOH/g or more and 250 mgKOH/g or less. In addition, 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. In particular, it is preferably 5,000 or more and 100,000 or less. Furthermore, it is more preferably 5,000 or more and 40,000 or less.

An isocyanate compound 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, there are trimer nurate types, adduct types reacted with 1,1,1-trimethylolpropane, and biuret types reacted with biuret.

The isocyanate compound may be selected from the above-mentioned isocyanate compounds or their polymers and derivatives, and one or a combination of two or more types may be used.

The overcoat layer 14 is formed, for example, 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 resin substrate 11 and reacting and curing it. The equivalent ratio (NCO/OH) of the NCO group of the isocyanate compound to the hydroxy group 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 the solvent include methyl acetate, ethyl acetate, butyl acetate, cyclohexanone, acetone, methyl ethyl ketone, dioxolane, tetrahydrofuran, etc. In practice, these solvents can be used alone or in combination of two or more.

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, an alkoxysilane, and a hydrolyzate thereof.

Preferred water-soluble polymers having hydroxyl groups are polyvinyl alcohol, polycarboxylic acid, starch, and cellulose. In particular, when polyvinyl alcohol (hereinafter referred to as PVA) is used in the coating agent of the present invention, the gas barrier properties are excellent. Since PVA is the polymer that contains the most hydroxyl groups in the monomer unit, it forms very strong hydrogen bonds with the hydroxyl groups of the organosilicon compound 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 the acetate groups remain, and fully saponified PVA in which only a few percent of the acetate groups remain. There are many types of molecular weight PVA, with a degree of polymerization ranging from 300 to several thousand, but there is no problem with the effect regardless of the molecular weight. However, in general, PVA with a high degree of saponification and a high molecular weight with a high degree of polymerization is preferred because it has high water resistance.

As the alkoxysilane, tetraethoxysilane, tetramethoxysilane, tetrapropoxysilane, methyltriethoxysilane, methyltrimethoxysilane, etc. can be used. As the hydrolysis product of the alkoxysilane, there can be mentioned one prepared by dissolving the alkoxysilane in an alcohol such as methanol, adding an aqueous solution of an acid such as hydrochloric acid to the solution, and carrying out a hydrolysis reaction. Through the hydrolysis reaction, the alkoxy group bonded to the silicon atom becomes a hydroxyl group, and the hydroxyl group is dehydrated and condensed to form a siloxane bond, forming a dense and strong network polymerized coating. As a result, an overcoat layer 14 having excellent heat resistance, water resistance, moisture resistance, bending resistance, stretch resistance, etc. can be obtained.

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-isocyanatopropyltriethoxysilane. These silane coupling agents can be used alone or in combination of two or more.

The thermoplastic resin forming the overcoat layer 14 is appropriately selected from polyols having two or more hydroxyl groups, such as acrylic polyol, polyester polyol, polycarbonate polyol, polyether polyol, polycaprolactone polyol, and epoxy polyol, polyvinyl resins such as polyvinyl acetate and polyvinyl chloride, polyvinylidene chloride resin, polystyrene resin, polyethylene resin, polypropylene resin, and polyurethane resin. Furthermore, these may 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.

As the ultraviolet-curable resin or electron beam-curable resin forming the overcoat layer 14, it is desirable to include at least a resin having a hydroxyl value in the range of 10 to 100 mgKOH/g as an organic polymer resin, although it is not particularly limited. Also, it is desirable to include at least a resin having an acid value in the range of 10 to 100 mgKOH/g as an organic polymer resin, although it is not particularly limited. Also, it is desirable to include at least a thermoplastic resin as an organic polymer 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 becomes weak, and the adhesion with the transparent oxide film layer 13 tends to be low. If the hydroxyl value or acid value exceeds 100 mgKOH/g, the precipitate containing the hydroxyl group generated by the decomposition of the overcoat layer 14 in a durability test such as a moist heat resistance test tends to hinder the adhesion between the overcoat layer 14 and the transparent oxide film layer 13.

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 this UV-curable resin or electron beam-curable resin include urethane acrylate, epoxy acrylate, and polyester acrylate.

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 overcoat layer 14, the blending ratio is not particularly limited.

The overcoat layer 14 may further contain additives other than the organic polymer resin as necessary. Examples of additives include antioxidants, weathering agents, heat stabilizers, lubricants, crystal nucleating agents, UV absorbers, plasticizers, antistatic agents, colorants, fillers, surfactants, and silane coupling agents.

The thickness of the overcoat layer 14 is not particularly limited and can be set as appropriate. It is preferably 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 effect of internal stress will be large, causing cracks.

As a method for forming the overcoat layer 14, a normal coating method can be used, as with the undercoat layer 12. For example, well-known methods such as dipping, roll coating, gravure coating, reverse coating, air knife coating, comma coating, die coating, screen printing, spray coating, gravure offset, and organic deposition can be used. As a drying method, one or more heat application methods such as hot air drying, heat roll drying, high frequency irradiation, infrared irradiation, UV irradiation, and electron beam irradiation can be used in combination. In addition, a film previously coated on another resin substrate by the above-mentioned formation method may be transferred to the transparent oxide film layer 13 using a transfer method such as adhesive transfer, heat transfer, and UV transfer.

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.

In Examples 1, 2, 3, 5, 6, 7, 9, 10, 11, and Comparative Examples 1, 2, 3, and 4, an undercoat layer 12 and a transparent oxide film layer 13 are provided in this order on one side of a resin substrate 11. In Examples 4, 8, and 12, an overcoat layer 14 is further provided on the transparent oxide film layer 13. That is, Examples 1, 2, 3, 5, 6, 7, 9, 10, 11, and Comparative Examples 1, 2, 3, and 4 correspond to the gas barrier laminate shown in FIG. 1. Examples 4, 8, and 12 correspond to the gas barrier laminate shown in FIG. 2.

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

[Preparation and application process of solution for undercoat layer]
As a solution for the undercoat layer 12, a multifunctional urethane acrylate, which is an ultraviolet curable resin, was diluted with ethyl acetate so that the solid content was 5% by mass. Furthermore, IRGACURE184 (manufactured by BASF) was added as an initiator at 2% of the mass of the ultraviolet curable resin and stirred to prepare a composition for forming an undercoat layer. Thereafter, the above-prepared solution was applied onto the resin substrate 11, which was dried in an oven at 80°C for 4 minutes, and then irradiated with 800 mJ/ ^cm2 ultraviolet light to form an undercoat layer having a thickness of 300 nm. In this way, a laminated film having an undercoat layer with an acryloyl group/urethane bond ratio of 5.0 and a Martens hardness of 500 N/ ^mm2 was obtained.

[Transparent oxide film layer lamination process]
A transparent oxide film layer 13 was formed on one side of the undercoat layer 12 by a sputtering method (referred to as method A) using a magnetron sputtering device in which two electrodes are positioned in parallel, and a positive and negative voltage can be applied alternately to each electrode, and each electrode alternately plays the role of a cathode and an anode. The film formation conditions were a film formation pressure of 0.30 Pa, a power density of 3.3 W/ ^cm2 , and a target of an alloy target of Si and W (atomic composition ratio Si:W=90:10). An MF power source was used as a means for applying power to the two electrodes. At that time, a rectangular voltage with a frequency of 40 kHz was applied to the two electrodes positioned in parallel. Argon gas and oxygen gas were used as gases. At this time, the flow rate of oxygen gas was controlled by detecting the emission intensity of plasma and the voltage value of discharge so that the state of the target surface was in a transition state in the middle of transition from metal mode to oxide mode. A gas barrier laminate was obtained by forming a transparent oxide film layer 13 with a thickness of 100 nm.

Example 2
A gas barrier laminate was obtained in the same manner as in Example 1, except that a bifunctional urethane acrylate, which is an ultraviolet-curable resin, was used as the solution for the undercoat layer 12, and a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 3.0 and a Martens hardness of 300 N/ ^mm2 was obtained.

Example 3
As a solution for the undercoat layer 12, a 5% ethyl acetate solution was prepared by using acrylic polyol (weight average molecular weight 10×10 ³ ) obtained by copolymerizing hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) as monomers as the main agent, and mixing 1 equivalent of an XDI adduct type isocyanate-based curing agent with respect to the amount of hydroxyl groups in the main agent. Then, the above-prepared solution was applied onto the resin substrate 11, and dried in an oven at 120° C. for 4 minutes to form an undercoat layer 12 with a thickness of 300 nm. In this way, a gas barrier laminate was obtained in the same manner as in Example 1, except that a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 1.5 and a Martens hardness of 210 N/mm ² was obtained.

Example 4
A transparent oxide film layer 13 was obtained in the same manner as in Example 1, except that an alloy target of Si and Sn (atomic composition ratio Si:Sn=50:50) was used.

[Preparation and application process of solution for overcoat layer]
A solution with a solid content of 5 mass % was prepared by mixing a hydrolysis solution of tetraethoxysilane (TEOS) and an aqueous solution of polyvinyl alcohol (PVA) so that the solid content ratio after drying would be 70:30, as a solution for the overcoat layer 14. Thereafter, the above-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.

Example 5
As a method for forming the transparent oxide film layer 13, a sputtering method (referred to as method B) using a magnetron sputtering device in which a voltage can be applied periodically to the electrode and a pulse having a different positive and negative polarity from the voltage application is applied during the off time of the voltage application was used, and a gas barrier laminate was obtained in the same manner as in Example 1, except that an alloy target of Si and Sn (atomic composition ratio Si:Sn=50:50) was used. At this time, a DC power source was used as a means for applying power to the electrode. At that time, a pulse voltage with a frequency of 10 kHz (on time: 95%, off time: 5%, negative voltage is applied during the on time and positive voltage is applied during the off time) was applied to the electrode. As film formation conditions, the film formation pressure was 0.30 Pa and the power density was 3.3 W/cm ^2. As gases, argon gas and oxygen gas were used, and the flow rate of the oxygen gas was adjusted so that an oxide film was obtained.

Example 6
A gas barrier laminate was obtained in the same manner as in Example 5, except that a bifunctional urethane acrylate, which is an ultraviolet-curable resin, was used as the solution for the undercoat layer 12, and a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 3.0 and a Martens hardness of 300 N/ ^mm2 was obtained.

Example 7
As a solution for the undercoat layer 12, a 5% ethyl acetate solution was prepared by using acrylic polyol (weight average molecular weight 10×10 ³ ) obtained by copolymerizing hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) as monomers as the main agent, and mixing 1 equivalent of an XDI adduct type isocyanate-based curing agent with respect to the amount of hydroxyl groups in the main agent. Then, the above-prepared solution was applied onto the resin substrate 11, and dried in an oven at 120° C. for 4 minutes to form an undercoat layer 12 with a thickness of 300 nm. In this way, a gas barrier laminate was obtained in the same manner as in Example 5, except that a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 1.5 and a Martens hardness of 210 N/mm ² was obtained.

Example 8
A transparent oxide film layer 13 was obtained in the same manner as in Example 5, except that an alloy target of Si and W (atomic composition ratio Si:W=90:10) was used.

[Preparation and application process of solution for overcoat layer]
The preparation and application process of the solution for the overcoat layer was the same as in Example 4, and an overcoat layer 14 having a thickness of 300 nm after drying was laminated on the transparent oxide film layer 13 to obtain a gas barrier laminate.

<Example 9>
As a method for forming the transparent oxide film layer 13, an atomic layer deposition method (referred to as method C) was used to form a film of SiAlOx as an atomic layer deposition film to a thickness of 25 nm. At this time, trisdimethylaminosilane (3DMAS) and trimethylaluminum (TMA) were used as the raw material gas (first precursor), O ₂ and N ₂ were used as the process gas, O ₂ and N ₂ were used as the purge gas, and O ₂ was used as the reactive gas (second precursor) and plasma discharge gas, and were supplied to the vacuum chamber. A 13.56 MHz power supply was used as the plasma excitation power supply, and plasma discharge (250 W) was performed in ICP (Inductively Coupled Plasma) mode to produce a laminate (first laminate) having an atomic layer deposition film. A gas barrier laminate was obtained in the same manner as in Example 1.

Example 10
A gas barrier laminate was obtained in the same manner as in Example 9, except that a bifunctional urethane acrylate, which is an ultraviolet-curable resin, was used as the solution for the undercoat layer 12, and a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 3.0 and a Martens hardness of 300 N/ ^mm2 was obtained.

Example 11
As a solution for the undercoat layer 12, a 5% ethyl acetate solution was prepared by using acrylic polyol (weight average molecular weight 10×10 ³ ) obtained by copolymerizing hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) as monomers as the main agent, and mixing 1 equivalent of an XDI adduct type isocyanate-based curing agent with respect to the amount of hydroxyl groups in the main agent. Then, the above-prepared solution was applied onto the resin substrate 11, and dried in an oven at 120° C. for 4 minutes to form an undercoat layer 12 with a thickness of 300 nm. In this way, a gas barrier laminate was obtained in the same manner as in Example 9, except that a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 1.5 and a Martens hardness of 210 N/mm ² was obtained.

Example 12
A transparent oxide film layer 13 was obtained in the same manner as in Example 9, except that trisdimethylaminosilane (3DMAS) and titanium tetrachloride (TiCl ₄ ) were used as raw material gases (first precursors) and a SiTiOx film was formed as an atomic layer deposition film to a thickness of 25 nm by atomic layer deposition.

[Preparation and application process of solution for overcoat layer]
The preparation and application process of the solution for the overcoat layer was the same as in Example 4, and an overcoat layer 14 having a thickness of 300 nm after drying was laminated on the transparent oxide film layer 13 to obtain a gas barrier laminate.

<Comparative Example 1>
To prepare a solution for the undercoat layer 12, urethane resin (weight average molecular weight 10×10 ³ ) was diluted with ethyl acetate to a solid content of 5% by mass. The solution prepared above was then applied onto the resin substrate 11, and dried in an oven at 120° C. for 4 minutes to form an undercoat layer 12 having a thickness of 300 nm. In this manner, a gas barrier laminate was obtained in the same manner as in Example 1, except that a laminate film having an undercoat layer with a Martens hardness of 100 N/mm ² was obtained.

<Comparative Example 2>
As a solution for the undercoat layer 12, a 5% ethyl acetate solution was prepared by using acrylic polyol (weight average molecular weight 10 x 103) obtained by copolymerizing hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) as monomers as the main agent, and mixing 2 equivalents of an XDI adduct type isocyanate-based curing agent relative to the amount of hydroxyl groups in the main agent. Then, the above-prepared solution was applied onto the resin substrate 11, and dried in an oven at 120 ° C. for 4 minutes to form an undercoat layer 12 with a thickness of 300 nm. In this way, a gas barrier laminate was obtained in the same manner as in Example 5, except that a laminate film having an undercoat layer with an acryloyl group/urethane bond ratio of 0.5 and a Martens hardness of 150 N/mm ² was obtained.

<Comparative Example 3>
A gas barrier laminate was obtained in the same manner as in Example ¹ , except that a solution for the undercoat layer 12 in which _SiO2 particles were dispersed in a multifunctional acrylate, which is an ultraviolet-curable resin, was used, and a laminate film having an undercoat layer with a Martens hardness of 400 N/mm2 was obtained.

<Comparative Example 4>
A gas barrier laminate was obtained in the same manner as in Example 7, except that a W target was used.

<Evaluation and Method>
[Martens hardness of undercoat layer]
The Martens hardness of the undercoat layer 12 was measured in accordance with ISO 14577 (-1, -2, -3). Specifically, it was measured using a nanoindentation system (product name: FischerScope HM2000Xyp) manufactured by Fisher Instruments Co., Ltd. A pyramidal diamond with an angle of 90 degrees was used, and the Martens hardness was expressed as the load at which a scratch width of 0.01 mm was created on the surface of the sample.

[Measurement of gas barrier properties of gas barrier laminate]
For the gas barrier laminates produced in Examples 1 to 12 and Comparative Examples 1 to 4, the water vapor permeability (g/m2·day) was measured under an environment of 40°C and 90% RH (temperature 40°C, relative humidity 90%) using a water vapor permeability meter ( ^AQUATRAN -Model II) manufactured by MOCON Corporation in the United States, using a method conforming to JIS-K7129. The helium permeability was measured using a pressure sensor type gas measuring device (Deltaperm DP-2MST) manufactured by Technolox, using a differential pressure method conforming to JIS K 7126A at 40°C and 0RH%.

[Abrasion test of gas barrier laminate and measurement of gas barrier property after abrasion test]
For Example 1, Example 2, Example 3, Example 5, Example 6, Example 7, Example 9, Example 10, Example 11, and Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4, which have a configuration in which an undercoat layer 12 and a transparent oxide film layer 13 are provided in this order on one side of a resin substrate 11, a steel wool #0000 was fixed to an abrasion tester, and a load of 75 g was applied, and a one-way abrasion test was performed on the transparent oxide film layer 13 of each sample. For the gas barrier laminate after the abrasion test, the water vapor permeability (g/m2·day) was measured in an environment of 40°C 90% RH (temperature 40°C, relative humidity 90%) using a water vapor permeability meter (AQUATRAN-Model II) manufactured by MOCON Corporation in the United States, using a method conforming to JIS- ^K7129 .

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

Comparing Examples 1, 2, 3, 5, 6, 7, 9, 10, and 11 corresponding to the first embodiment with Comparative Examples 1 and 3, Examples 1, 2, 3, 5, 6, 7, 9, 10, and 11, which use an acrylic urethane resin for the undercoat layer 12 and contain both an acryloyl group and a urethane bond, showed better results in both water vapor permeability and helium permeability than Comparative Example 1, which uses a urethane resin for the undercoat layer 12 and contains only urethane bonds, and Comparative Example 3, which uses an acrylic resin and _SiO2 particles for the undercoat layer 12 and contains only acryloyl groups. In addition, good results were also obtained in terms of water vapor permeability after the scratch test.

Comparing Examples 1, 2, 3, 5, 6, 7, 9, 10, and 11 corresponding to the first embodiment with Comparative Example 2, Examples 1, 2, 3, 5, 6, 7, 9, 10, and 11, which use an acrylic urethane resin for the undercoat layer 12, contain both acryloyl groups and urethane bonds, and have more acryloyl groups than urethane bonds, showed better results in both water vapor permeability and helium permeability than Comparative Example 2, which uses an acrylic urethane resin for the undercoat layer 12, contains both acryloyl groups and urethane bonds, but has fewer acryloyl groups than urethane bonds. In addition, the water vapor permeability after the scratch test was also good.

Comparing Example 7 and Comparative Example 4, which correspond to the first embodiment and use Method B for the film formation method, Example 7, in which the target and transparent oxide film layer 13 contain Si and Sn as metal elements, gave better results in both water vapor permeability and helium permeability than Comparative Example 4, in which the target and transparent oxide film layer 13 contain only W. In addition, the water vapor permeability after the scratch test also gave better results.

In Example 5, the film formation method was Method B, and in Example 9, the film formation method was Method C. However, similar to Example 1, in which the film formation method was Method A, good results were obtained for water vapor permeability and helium permeability, and in addition, good results were obtained for water vapor permeability after the scratch resistance test.

Examples 4, 8, and 12, which correspond to the second embodiment, have an overcoat layer 14 laminated thereon, but similar to Examples 1, 2, 3, 5, 6, 7, 9, 10, and 11, which correspond to the first embodiment and do not have an overcoat layer 14 laminated thereon, good water vapor permeability and helium permeability results were obtained.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and even if the modifications do not deviate from the gist of the present invention, they are included in the present invention.

The gas barrier laminate of the present invention is expected to be particularly suitable for use in fields such as electronic device-related materials, where high gas barrier properties are required.

11: Resin substrate 12: Undercoat layer 13: Transparent oxide film layer 14: Overcoat layer

Claims (5)

A gas barrier laminate comprising a resin substrate, an undercoat layer laminated on at least one side of the resin substrate, and a transparent oxide film layer laminated on the undercoat layer,
the undercoat layer is made of a cured film of a compound having at least an acryloyl group and a urethane bond, and the ratio of the number of acryloyl groups to the number of urethane bonds is 1.5 to 5.0;
The undercoat layer has a Martens hardness of 200 N/mm2 or ^more .
The transparent oxide film layer is a physical vapor deposition film containing at least silicon (Si) and any one of tin (Sn) and tungsten (W) ,
A gas barrier laminate characterized in that the water vapor transmission rate measured under conditions of 40° C. and 90% R.H. is 0.01 g/( ^m2 ·day) or less, and the helium transmission rate measured under conditions of 40° C. and 0% R.H. is 4 cc/( ^m2 ·day·atm) or less. The gas barrier laminate according to claim 1, wherein the thickness of the undercoat layer is 0.05 μm or more and 10 μm or less. 3. The gas barrier laminate according to claim 1 or 2 , which has a water vapor permeability of 0.050 g/( ^m2 ·day) or less after an abrasion test (using steel wool #0000, a load of 75 g, one round trip) under measurement conditions of 40° C. and 90% R.H. The gas barrier laminate according to any one of claims 1 to 3, further comprising an overcoat layer on the outer side of the transparent oxide film layer, the overcoat layer being formed from at least one of a thermosetting resin, a thermoplastic resin, an ultraviolet curing resin, and an electron beam curing resin. 5. The gas barrier laminate according to claim 4 , wherein the overcoat layer is formed containing a water-soluble polymer having a hydroxyl group, and at least one selected from the group consisting of alkoxysilanes and hydrolysates thereof.