JP5857797B2 - Gas barrier film - Google Patents

Description

  The present invention relates to a transparent gas barrier film that is excellent in high gas barrier properties and transparency, and has excellent flex resistance that does not deteriorate the gas barrier properties even when the substrate is bent or deformed.

  Physical vapor deposition methods such as vacuum deposition, sputtering, and ion plating using inorganic materials (including inorganic oxides) such as aluminum oxide, silicon oxide, and magnesium oxide on the surface of the polymer film substrate ( PVD method) or chemical vapor deposition method (CVD method) such as plasma chemical vapor deposition method, thermal chemical vapor deposition method, photochemical vapor deposition method, etc. The transparent gas barrier film thus formed is used as a packaging material for foods, pharmaceuticals, and the like that require blocking of various gases such as water vapor and oxygen, and as an electronic device member such as a flat-screen TV and a solar battery.

  As a gas barrier property improving technique, for example, at least one kind of carbon, hydrogen, silicon, and oxygen is mainly formed on a base material by a plasma CVD method using a gas containing an organic silicon compound vapor and oxygen. A method of improving gas barrier properties while maintaining transparency by using a compound that has been contained is used (Patent Document 1). Further, as a gas barrier property improving technique other than the plasma CVD method, a catalytic CVD method is used in which a silicon nitride film is formed on the surface of a film by catalytically decomposing silane gas, ammonia gas, and hydrogen gas to a tungsten wire heated at a high temperature ( Patent Document 2).

JP-A-8-142252 (Claims) JP 2006-57121 A (Claims)

  However, in the method of forming a gas barrier layer mainly composed of silicon oxide by the plasma CVD method, the formed gas barrier layer is a very dense and high hardness layer. There was a problem that it was impossible to follow the deformation of the substrate with respect to the environment and bending, cracks were generated in the silicon oxide layer, and gas barrier properties were lowered. Furthermore, the silicon oxide layer formed by the plasma CVD method has a problem that the film is colored yellow because the color tone is yellow due to light absorption in the vicinity of a wavelength of 400 nm.

  On the other hand, the method of forming a silicon nitride film by the catalytic CVD method is a process in which the catalyst body such as tungsten or platinum wire is heated to 1000 ° C. or higher, so that the substrate is greatly damaged by the radiant heat of the catalyst body, and the polymer film There was a problem that the base material was warped due to heat loss, and workability was deteriorated in the post-processing. Further, in terms of optical characteristics, since the refractive index of the silicon nitride film is as high as 1.9 or more at a wavelength of 550 nm, there are problems such as a decrease in average light transmittance and interference fringes accompanying an increase in optical reflectance.

  In view of the background of such prior art, the present invention is to provide a gas barrier film having a high transparency and a high gas barrier property that does not deteriorate the gas barrier property even in a high temperature environment and bending.

The present invention employs the following means in order to solve such problems. That is,
(1) A gas barrier film in which a composite layer including the following [A] layer and [B] layer is disposed on at least one surface of a transparent substrate.
[A] layer: a layer comprising a coexisting phase of zinc oxide-silicon dioxide-aluminum oxide [B] layer: a layer comprising a coexisting phase of zinc sulfide and silicon dioxide (2) The [A] layer is an ICP emission spectroscopic analysis method. The zinc (Zn) atom concentration measured by the above is 20.0 to 40.0 atom%, the silicon (Si) atom concentration is 5.0 to 20.0 atom%, and the aluminum (Al) atom concentration is 0.5 to 5.0 atom. %, And the oxygen (O) atom concentration is 35.0 to 70.0 atom%. (3) The [B] layer has a mole fraction of zinc sulfide of 0.7 to 0 with respect to the total of zinc sulfide and silicon dioxide. (4) The refractive index of the [A] layer is in the range of 1.5 to 1.8 at a wavelength of 550 nm, and the refractive index of the [B] layer is at a wavelength of 550 nm. It is in the range of 0 to 2.4 (5) The composite layer is the [A] layer and / or Or a layer having the following [C] layer in contact with the [B] layer [C] layer: silicon oxide layer (6) The thickness of the [C] layer is the [A] layer, 5 to 40% of the total thickness of the [B] layer and the [C] layer (7) The thickness of the [C] layer is 5 to 300 nm (8) Refraction of the [C] layer The rate is in the range of 1.43 to 1.50 at a wavelength of 550 nm. (9) The transparent substrate has a resin layer on at least the side having the composite layer. (10) The composite layer A transparent conductive layer containing any one of indium tin oxide (ITO), zinc oxide (ZnO), and aluminum-containing zinc oxide (Al / ZnO) is formed on the surface not in contact with the transparent substrate. Is a preferred embodiment.

  According to the present invention, it is possible to provide a transparent gas barrier film that does not deteriorate high gas barrier properties against oxygen gas, water vapor, and the like even in a high temperature environment and bending.

It is sectional drawing which showed an example of the gas barrier film of this invention. It is an example of sectional drawing which showed the structure of the gas barrier film of this invention. It is an example of sectional drawing which showed the structure of the gas barrier film of this invention. It is an example of sectional drawing which showed the structure of the gas barrier film of this invention. It is an example of sectional drawing which showed the structure of the gas barrier film of this invention. It is the schematic of a bending resistance test. It is the schematic which shows typically the winding-type sputtering apparatus for manufacturing the gas barrier film of this invention.

The inventors of the present invention have made extensive studies for the purpose of obtaining a gas barrier film having high transparency and water vapor barrier properties and good bending resistance, and zinc oxide (hereinafter sometimes abbreviated as ZnO) and dioxide dioxide. [A] layer comprising a zinc oxide-silicon dioxide-aluminum oxide coexisting phase containing silicon (hereinafter sometimes abbreviated as SiO ₂ ) and aluminum oxide (hereinafter also abbreviated as Al ₂ O ₃ ), and sulfide A gas barrier comprising a composite layer in which a zinc sulfide (hereinafter sometimes abbreviated as ZnS) and silicon dioxide (hereinafter also abbreviated as SiO ₂ ) and a [B] layer composed of a zinc sulfide-silicon dioxide coexisting phase is laminated. When used as a layer, it has been found that the above problems can be solved at once. In the present invention, the bending resistance means not only that it is not easily broken at the time of bending, but also that the water barrier property does not decrease even after bending.

FIG. 1 is a cross-sectional view showing an example of the gas barrier film of the present invention. As shown in FIG. 1, the gas barrier film of the present invention has a layer composed of a zinc oxide-silicon dioxide-aluminum oxide coexisting phase as [A] layer 2 and [B] layer 3 on the surface of transparent substrate 1. A composite layer including a layer composed of a coexisting phase of zinc sulfide and silicon dioxide is disposed. In FIG. 1, the [A] layer 2 is formed on the transparent substrate 1 side, but the [B] layer 3 may be provided on the transparent substrate 1 side (FIG. 2).
[Gas barrier film]
The gas barrier film of the present invention is a gas barrier film in which a composite layer including an [A] layer and a [B] layer is disposed as a gas barrier layer on at least one surface of a transparent substrate. The gas barrier film of the present invention is preferably a composite layer having a silicon oxide layer ([C] layer) so that the gas barrier layer is in contact with the [A] layer and / or the [B] layer.

  Although the details of each layer will be described later, the [A] layer and the [B] layer are gas barrier layers having a relatively high water vapor barrier property and a relatively high flexibility, and these layers are combined. As a result, a gas barrier property having an unprecedented high flexibility has been achieved. Furthermore, when they were arranged so as to contact each other, a gas barrier film having high water vapor barrier properties and flexibility that could not be achieved by a single layer configuration of the [A] layer or the [B] layer could be obtained. The reason why such a remarkable effect can be obtained is estimated as follows. Both have a common composition and good affinity due to the inclusion of silicon oxide. By adopting a laminated structure in which they are placed in contact with each other, they are strongly bonded and block oxygen and water vapor while maintaining high flexibility. I think that it improved the nature. As described above, the laminated structure in which the [A] layer and the [B] layer are arranged in contact with each other is preferable, and a multilayer laminate in which the [A] layer and the [B] layer are repeatedly laminated as long as flexibility is ensured. It does not matter as a configuration. Further, from the viewpoint of further improving gas barrier properties, it is preferable to laminate the [C] layer so as to be in contact with the [A] layer and / or the [B] layer. The reason for this is estimated as follows. That is, the [C] layer contains silicon oxide as a common composition with the [A] layer and [B] layer described above, and the silicon oxide particles constituting the [C] layer are fine. Therefore, by laminating the [A] layer and / or the [B] layer so as to be in contact with each other, a defect portion existing in the surface layer of the [A] layer and the [B] layer constitutes the [C] layer. This is thought to be due to the effect of the silicon oxide particles filling the holes. For this reason, it is considered that by laminating the [C] layer, the gas barrier property can be further improved without deteriorating the flexibility. As an aspect of laminating the [C] layer so as to be in contact with the [A] layer and / or the [B] layer, for example, as shown in FIG. [B] layer 3 and [C] layer 4 may be arranged on top of each other (in this case, [C] layer is in contact with [B] layer). As shown in FIG. [B] layer 3 is laminated on the surface of 1 and [C] layer 4 is laminated, and further [A] layer 2 is arranged (in this case, [C] layer is in contact with [A] layer and [B] layer). Can also). Further, as shown in FIG. 5, the [C] layer may be laminated on each of the [B] layer 3 and the [A] layer 2 or these may be further repeated.

  The gas barrier layer may be disposed on one side of the transparent substrate 1, or the stress balance is adjusted when the stress balance on the opposite side of the gas barrier layer is lost on one side and the gas barrier film is warped or deformed. For the purpose, gas barrier layers may be provided on both sides of the transparent substrate.

  In addition, the [A] layer used in the present invention is a layer having a lower refractive index at a wavelength of 550 nm than the [B] layer (hereinafter simply referred to as a refractive index, it indicates a refractive index at a wavelength of 550 nm). Therefore, by adjusting and laminating the film thickness of the [A] layer and the [B] layer, it is possible to reduce the light reflection and improve the light transmittance, and the gas barrier having high transparency and water vapor blocking property. Can be obtained. For example, in the case of a composite layer configuration formed of an [A] layer and a [B] layer, the outermost layer of the composite layer uses the [A] layer close to the refractive index of the outside air to reflect light from outside light. Is preferable because the light transmission can be improved. When the composite layer is composed of the [A] layer, the [B] layer, and the [C] layer, it is more light for the outermost layer to use the [C] layer closer to the refractive index of the outside air than the [A] layer as the outer layer. It is preferable from the viewpoint of permeability. The stacking order of the layers stacked on the substrate side from the outermost layer is not particularly limited, and the light transmittance can be improved by adjusting the film thickness of each layer.

  Further, when the gas barrier layer is disposed on one side of the transparent substrate 1 and the gas barrier film is warped or deformed, the gas barrier layer cannot follow the warping or deformation of the transparent substrate, cracks are generated, and the gas barrier property is increased. In such a case, a resin layer may be laminated between each layer of the composite layer including the [A] layer and the [B] layer. By laminating the resin layer, the stress of the gas barrier layer can be relaxed, and the flexibility of the transparent substrate against warping and deformation can be improved.

  In the product of the present invention, a resin layer may be formed on the outermost layer from the viewpoint of protecting the surface of the gas barrier layer.

In addition, the product of the present invention has indium tin oxide (ITO), zinc oxide (on the [A] layer or [B] layer disposed on the outermost layer side of the gas barrier layer as long as transparency and flexibility do not deteriorate. A transparent conductive layer containing either ZnO) or aluminum-containing zinc oxide (Al / ZnO) may be formed.
[Transparent substrate]
The transparent substrate used in the present invention is not particularly limited as long as it is a film made of an organic polymer compound. For example, polyolefin such as polyethylene or polypropylene, polyester such as polyethylene terephthalate or polyethylene naphthalate, polyamide, polycarbonate, polystyrene Films made of various polymers such as polyvinyl alcohol, saponified ethylene vinyl acetate copolymer, polyacrylonitrile, polyacetal, and the like can be used. Among these, a film made of polyethylene terephthalate is preferable. The polymer constituting the transparent substrate may be either a homopolymer or a copolymer, or may be a single polymer or a blend of a plurality of polymers.

  Further, as the transparent substrate, a single layer film, a film having two or more layers, for example, a film formed by a coextrusion method, a film stretched in a uniaxial direction or a biaxial direction, or the like may be used. In order to improve adhesion, the base material surface on the side on which the gas barrier layer is formed has an anchor composed of corona treatment, ion bombardment treatment, solvent treatment, roughening treatment, and organic or inorganic matter or a mixture thereof. A pretreatment such as a coating layer forming treatment may be performed. Also, on the surface opposite to the side on which the gas barrier layer is formed, the purpose is to improve the slipping property when winding the film and to reduce the friction with the gas barrier layer when winding the film after forming the gas barrier layer. Further, a coating layer of an organic material, an inorganic material, or a mixture thereof may be provided.

The thickness of the transparent substrate used in the present invention is not particularly limited, but is preferably 500 μm or less from the viewpoint of ensuring flexibility, and preferably 5 μm or more from the viewpoint of ensuring strength against tension or impact. Furthermore, the lower limit is more preferably 10 μm or more, and the upper limit is more preferably 200 μm or less because of the ease of film processing and handling.
[Layer consisting of a coexisting phase of zinc oxide-silicon dioxide-aluminum oxide]
Next, details of a layer composed of a zinc oxide-silicon dioxide-aluminum oxide coexisting phase (hereinafter abbreviated as [A] layer) will be described. The “coexisting phase of zinc oxide-silicon dioxide-aluminum oxide” may be abbreviated as “ZnO—SiO ₂ —Al ₂ O ₃ ”. Also, silicon (SiO ₂₎ dioxide, the generation time of the condition, those slightly deviated from the composition ratio of silicon and oxygen on the left formula (SiO~SiO ₂₎ although it is possible to produce, in this specification It will be expressed as silicon dioxide or SiO ₂ . Regarding the deviation of the composition ratio from the chemical formula, the same applies to zinc oxide and aluminum oxide. In this specification, zinc oxide or ZnO is used regardless of the deviation of the composition ratio depending on the conditions at the time of production. In this case, it is expressed as aluminum oxide or Al ₂ O ₃ .

  As a result of investigations by the inventors, it has been found that when the [A] layer is used, a gas barrier film having good gas barrier properties and excellent flexibility against mechanical bending caused by external stress can be obtained.

The thickness of the [A] layer used in the present invention is preferably 10 nm or more and 500 nm or less as the thickness of the layer that exhibits the gas barrier property of the [A] layer. When the thickness of the layer is less than 10 nm, there may be a portion where the gas barrier property cannot be sufficiently secured, and there may be a problem that the gas barrier property varies within the substrate surface. When the thickness of the layer is greater than 500 nm, the stress remaining in the layer of the [A] layer increases, so that a crack occurs in the [A] layer in a high-temperature and high-humidity environment, resulting in a problem that the gas barrier property decreases. There is. From the viewpoint of ensuring flexibility, the lower limit is more preferably 20 nm or more, and the upper limit is more preferably 300 nm or less. The thickness of the [A] layer can be usually measured by cross-sectional observation with a transmission electron microscope (TEM). (Note that in the boundary region between the [A] layer and the [B] layer or the [C] layer, the boundary of the layer and the thickness of the layer when the composition changes in a gradient and a clear interface cannot be visually recognized) The definition and confirmation method will be described later.)
The reason why the gas barrier property is improved by applying the [A] layer in the gas barrier film of the present invention is that, in the zinc oxide-silicon dioxide-aluminum oxide coexisting phase, the crystalline component contained in the zinc oxide and the glass of silicon dioxide It is presumed that the coexistence of the fine component suppresses the crystal growth of zinc oxide, which is likely to generate microcrystals, and the particle size is reduced, so that the layer is densified and the permeation of oxygen and water vapor is suppressed.

  In addition, the reason why the bending resistance is good is that, by making aluminum oxide coexist, crystal growth can be suppressed more than in the case of coexisting zinc oxide and silicon dioxide, and therefore it is caused by generation of cracks. It is considered that the gas barrier property decrease was suppressed.

  The composition of the [A] layer can be measured by ICP emission spectroscopy as described later. Zn atom concentration measured by ICP emission spectroscopy is 20.0-40.0 atom%, Si atom concentration is 5.0-20.0 atom%, Al atom concentration is 0.5-5.0 atom%, O atom The concentration is preferably 35.0 to 70.0 atom%. If the Zn atom concentration is higher than 40.0 atom% or the Si atom concentration is lower than 5.0 atom%, there will be insufficient oxide to suppress the crystal growth of zinc oxide. Gas barrier properties may not be obtained. When the Zn atom concentration is less than 20.0 atom%, or the Si atom concentration is more than 20.0 atom%, the glassy component of silicon dioxide inside the layer may increase and the flexibility of the layer may decrease. Further, when the Al atom concentration is higher than 5.0 atom%, the affinity between zinc oxide and silicon dioxide becomes excessively high, so that the film hardness increases, and cracks are likely to occur due to heat and external stress. is there. When the Al atom concentration is less than 0.5 atom%, the affinity between zinc oxide and silicon dioxide becomes insufficient, and the bonding force between the particles forming the layer cannot be improved, so that the flexibility may be lowered. Further, when the O atom concentration is higher than 70.0 atom%, the amount of defects in the [A] layer increases, so that a predetermined gas barrier property may not be obtained. When the O atom concentration is less than 35.0 atom%, the oxidation state of zinc, silicon, and aluminum becomes insufficient, and light absorption occurs in the visible light region with a wavelength of 380 to 780 nm, resulting in reduction in coloring and light transmittance. There is a case. From this point of view, the Zn atom concentration is 25.0-35.0 atom%, the Si atom concentration is 10.0-15.0 atom%, the Al atom concentration is 1.0-3.0 atom%, and the O atom concentration is 50.0. More preferably, it is ˜65.0 atom%.

  The component contained in the [A] layer is not particularly limited as long as zinc oxide, silicon dioxide, and aluminum oxide are in the above composition and are main components. For example, Al, Ti, Zr, Sn, In, Nb, Mo, A metal oxide formed of Ta, Pd, or the like may be included. Here, the main component usually means 60% by mass or more of the composition of the [A] layer, and preferably 80% by mass or more.

  In addition, by setting the refractive index of the [A] layer in the range of 1.5 to 1.8 at a wavelength of 550 nm, the light transmittance of the gas barrier film is improved while maintaining further excellent gas barrier properties and bending resistance. It is preferable because it can be used. When the refractive index at a wavelength of 550 nm is smaller than 1.5, the gap between the particles of the component constituting the [A] layer becomes large, so that the gas and water vapor are easily transmitted, and the gas barrier property is lowered. Problems may occur. On the other hand, when the refractive index is higher than 1.8, the light reflection of the [A] layer increases, and the light transmittance of the gas barrier film may be lowered. More preferably, it is the range of 1.6-1.7.

  Since the composition of the [A] layer is formed with the same composition as the mixed sintered material used when forming the layer, the composition of the [A] layer can be changed by using a mixed sintered material having a composition suitable for the purpose. It is possible to adjust.

[A] The composition analysis of the layer uses ICP emission spectroscopic analysis to quantitatively analyze each element of zinc, silicon, and aluminum, and determine the composition ratio of zinc oxide, silicon dioxide, aluminum oxide, and the contained inorganic oxide. I can know. The oxygen atoms are calculated on the assumption that zinc atoms, silicon atoms, and aluminum atoms exist as zinc oxide (ZnO), silicon dioxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ), respectively. The ICP emission spectroscopic analysis is an analysis method capable of simultaneously measuring multiple elements from an emission spectrum generated when a sample is introduced into a plasma light source unit together with argon gas, and can be applied to composition analysis. When an inorganic layer or a resin layer is laminated on the [A] layer, ICP emission spectroscopic analysis can be performed after removing the layer by ion etching or chemical treatment as necessary.

The method for forming the [A] layer on the transparent substrate is not particularly limited. By using a mixed sintered material of zinc oxide, silicon dioxide and aluminum oxide, a vacuum deposition method, a sputtering method, an ion plating method, etc. Can be formed. When using a single material of zinc oxide, silicon dioxide, and aluminum oxide, form a film of zinc oxide, silicon dioxide, and aluminum oxide simultaneously from separate vapor deposition sources or sputter electrodes, and mix them to the desired composition. Can be formed. Among these methods, the [A] layer forming method used in the present invention is more preferably a sputtering method using a mixed sintered material from the viewpoint of gas barrier properties and composition reproducibility of the formed layer.
[Layer consisting of a coexisting phase of zinc sulfide and silicon dioxide]
Next, details of a layer composed of a coexisting phase of zinc sulfide and silicon dioxide (hereinafter abbreviated as [B] layer) will be described. In the [B] layer, the molar fraction of zinc sulfide relative to the total of zinc sulfide and silicon dioxide is preferably 0.7 to 0.9. The “zinc sulfide-silicon dioxide coexisting phase” is sometimes abbreviated as “ZnS—SiO ₂ ”. Further, silicon dioxide (SiO _2), depending on the conditions at the time of generation, those slightly deviated from the composition ratio of silicon and oxygen on the left formula (SiO~SiO ₂₎ although it is possible to produce, in the present specification Is expressed as silicon dioxide or SiO ₂ .

The thickness of the [B] layer used in the present invention is preferably 10 nm or more and 500 nm or less as the thickness of the layer that exhibits the gas barrier property of the [B] layer. When the thickness of the layer is less than 10 nm, there may be a portion where the gas barrier property cannot be sufficiently secured, and the gas barrier property may vary within the substrate surface. If the thickness of the layer is greater than 500 nm, the stress remaining in the layer of the [B] layer increases, so that a crack may occur in the [B] layer in a high-temperature and high-humidity environment, and gas barrier properties may be reduced. From the viewpoint of ensuring flexibility, the lower limit is more preferably 20 nm or more, and the upper limit is more preferably 300 nm or less. [B] The thickness of the layer can usually be measured by cross-sectional observation with a transmission electron microscope (TEM). (Note that, in the boundary region between the [B] layer and the [A] layer or the [C] layer, the composition changes in a gradient and a clear interface cannot be visually recognized. The definition and confirmation method will be described later.)
The reason why the gas barrier property is improved by applying the [B] layer in the transparent conductive laminate of the present invention is that the crystalline component contained in zinc sulfide and the glassy component of silicon dioxide in the zinc sulfide-silicon dioxide coexisting phase It is presumed that the crystal growth of zinc sulfide, which tends to generate microcrystals, is suppressed and the particle size is reduced, so that the layer is densified and the permeation of oxygen and water vapor is suppressed. In addition, the zinc sulfide-silicon dioxide coexisting phase containing zinc sulfide with suppressed crystal growth is more flexible than a layer formed only of inorganic oxides or metal oxides. Therefore, it is considered that the deterioration of the gas barrier property due to the generation of cracks could be suppressed by applying such a [B] layer.

  The composition of the [B] layer is preferably such that the molar fraction of zinc sulfide relative to the total of zinc sulfide and silicon dioxide is 0.7 to 0.9. If the molar fraction of zinc sulfide with respect to the total of zinc sulfide and silicon dioxide is greater than 0.9, there will be insufficient oxide that suppresses crystal growth of zinc sulfide, resulting in an increase in voids and defects, resulting in a predetermined gas barrier property. May not be obtained. In addition, when the mole fraction of zinc sulfide with respect to the total of zinc sulfide and silicon dioxide is less than 0.7, the glassy component of silicon dioxide in the [B] layer increases and the flexibility of the layer decreases. The flexibility of the gas barrier film against general bending may be reduced. More preferably, it is the range of 0.75-0.85.

  The component contained in the [B] layer is not particularly limited as long as zinc sulfide and silicon dioxide are in the above composition and are the main components. For example, Al, Ti, Zr, Sn, In, Nb, Mo, Ta, Pd A metal oxide formed from the above may be included. Here, the main component usually means 60% by mass or more of the composition of the [B] layer, and preferably 80% by mass or more.

  In addition, it is preferable to set the refractive index of the [B] layer in the range of 2.0 to 2.4 at a wavelength of 550 nm because further excellent gas barrier properties and bending resistance can be obtained. When the refractive index at a wavelength of 550 nm is smaller than 2.0, the film quality is large in the gaps between the particles of the component constituting the [B] layer, so that gas and water vapor are easily transmitted, and the gas barrier property may be lowered. is there. Moreover, when a refractive index becomes larger than 2.4, the light reflection of a [B] layer will become large and the light transmittance of a gas barrier film may fall. More preferably, it is the range of 2.2-2.3.

  Since the composition of the [B] layer is formed with the same composition as the mixed sintered material used at the time of forming the layer, the composition of the [B] layer can be changed by using a mixed sintered material having a composition suitable for the purpose. It is possible to adjust.

  In the composition analysis of the layer [B], first, the composition ratio of zinc and silicon is obtained by ICP emission spectroscopic analysis. Based on this value, each element is quantitatively analyzed by using Rutherford backscattering method, and zinc sulfide and silicon dioxide and The composition ratio of other inorganic oxides contained can be known. The ICP emission spectroscopic analysis is an analysis method capable of simultaneously measuring multiple elements from an emission spectrum generated when a sample is introduced into a plasma light source unit together with argon gas, and can be applied to composition analysis. In Rutherford backscattering method, a charged particle accelerated by a high voltage is irradiated on a sample, and the number of charged particles bounced from the sample and the element are identified and quantified from the energy, and the composition ratio of each element can be known. In addition, since the [B] layer is a composite layer of sulfide and oxide, analysis by Rutherford back scattering method capable of analyzing the composition ratio of sulfur and oxygen is performed. [B] When an inorganic layer or a resin layer is laminated on the layer, the layer may be removed by ion etching or chemical treatment as necessary, and then analyzed by ICP emission spectroscopic analysis or Rutherford backscattering method. it can.

The method for forming the [B] layer on the transparent substrate is not particularly limited, and it is formed by a vacuum deposition method, a sputtering method, an ion plating method or the like using a mixed sintered material of zinc sulfide and silicon dioxide. Can do. When a single material of zinc sulfide and silicon dioxide is used, it can be formed by simultaneously forming films of zinc sulfide and silicon dioxide from different vapor deposition sources or sputtering electrodes, and mixing them to obtain a desired composition. Among these methods, the [B] layer forming method used in the present invention is more preferably a sputtering method using a mixed sintered material from the viewpoint of gas barrier properties and composition reproducibility of the formed layer.
[Silicon oxide layer]
Next, the details of the silicon oxide layer (hereinafter abbreviated as [C] layer) will be described. By laminating the [C] layer so as to be in contact with the [A] layer and / or the [B] layer, the gas barrier property can be dramatically improved while ensuring the flexibility of the composite layer. The reason why the gas barrier property is improved is not clear. However, when the [C] layer is formed, a silicon compound is probably present in a defect portion existing in the [A] layer or the [B] layer under the [C] layer. Since it is filled, the surface layer portion of the [A] layer or the [B] layer under the [C] layer is densified, and as a result, the gas barrier property is considered to be improved.

  In the composition of the [C] layer, the atomic ratio of oxygen atoms to silicon atoms is preferably 1.5 to 2.0. When the ratio of the number of oxygen atoms to silicon atoms is larger than 2.0, the amount of oxygen atoms contained increases, so that void portions and defect portions increase, and a predetermined gas barrier property may not be obtained. On the other hand, when the atomic ratio of oxygen atoms to silicon atoms is smaller than 1.5, oxygen atoms are reduced to obtain a dense film quality, but flexibility may be lowered. More preferably, it is the range of 1.4-1.8.

  The composition analysis of the [C] layer can be performed by quantitatively analyzing the atomic weight of each element using X-ray photoelectron spectroscopy (XPS method) and knowing the composition ratio of the atomic ratio of oxygen atoms to silicon atoms.

When the [C] layer is larger than 40% of the total thickness of the [A] layer, the [B] layer, and the [C] layer, the flexibility of the entire gas barrier layer is lowered. Flexibility may be reduced. Further, when the [C] layer is smaller than 5% of the total thickness of the [A] layer, the [B] layer, and the [C] layer, a sufficient gas barrier property improvement effect may not be obtained. Accordingly, the [C] layer is preferably in the range of 5 to 40% of the total thickness of the [A] layer, [B] layer, and [C] layer, and more preferably in the range of 15 to 30%. . In addition, the [C] layer has a yellow color due to light absorption in the vicinity of a wavelength of 400 nm, which is a characteristic of silicon oxide, and the film may be colored yellow, so the film thickness is preferably 300 nm or less. Moreover, since the effect which improves gas-barrier property may become inadequate when a film thickness becomes smaller than 5 nm, 5 nm or more is preferable. Therefore, the film thickness of the [C] layer is preferably in the range of 5 to 300 nm, more preferably in the range of 50 to 200 nm. The thickness of the [C] layer can usually be measured by cross-sectional observation with a transmission electron microscope (TEM). (Note that, in the boundary region between the [C] layer and the [A] layer or the [B] layer, the composition changes in a gradient and a clear interface cannot be visually recognized. The definition and confirmation method will be described later.)
The refractive index of the [C] layer used in the present invention varies depending on the formation method and conditions. From the viewpoint of reducing light reflection and improving the light transmittance of the entire gas barrier film, the [A] layer and [B] A lower refractive index than the layer is preferred. The refractive index at a wavelength of 550 nm is preferably 1.43 to 1.50, more preferably 1.45 to 1.47. When the refractive index is smaller than 1.43, the grain boundary of the particles of the component [C] layer becomes a film quality, so that gas and water vapor are easily transmitted, and the gas barrier property may be lowered. On the other hand, if the refractive index is greater than 1.50, light absorption near a wavelength of 400 nm increases, and the color tone of the gas barrier film may deteriorate.

The method for forming the [C] layer is not particularly limited, and can be formed by, for example, a CVD method, a vacuum deposition method, a sputtering method, an ion plating method, or the like. Among these methods, as a method for forming a silicon compound layer used in the present invention, a CVD method in which a monomer gas of a silane compound is activated by plasma and a [C] layer is formed by a polymerization reaction is applied. Alternatively, it is preferable because defects on the surface of the [B] layer can be efficiently filled to dramatically improve the gas barrier property. Examples of silane compounds that can be applied to such a CVD method include silane, methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, ethylsilane, diethylsilane, triethylsilane, tetraethylsilane, propoxysilane, dipropoxysilane, and tripropoxy. Silane, tetrapropoxysilane, dimethyldisiloxane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetramethyldisiloxane, hexamethyldisiloxane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, hexamethylcyclotrisiloxane, Octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, undecamethylcyclohexasiloxane, dimethyldisilazane, Trimethyl disilazane, tetramethyl disilazane, hexamethyl disilazane, hexamethylcyclotrisilazane, octamethylcyclotetrasilazane, decamethylcyclopentasiloxane silazane, such undecapeptide methyl cyclohexasilane La disilazane and the like. Of these, hexamethyldisiloxane and tetraethoxysilane are preferable in terms of safety in handling.
[Confirmation method of layer structure when boundaries of layers A to C cannot be visually recognized only by TEM]
In the composite layer of the gas barrier film of the present invention, there is a clear interface on the TEM because the composition of the boundary region of each layer of the [A] layer, [B] layer, and [C] layer changes in a slanting manner. In the case where it cannot be visually recognized, first, the composition analysis in the thickness direction is performed to obtain the concentration distribution of the element in the thickness direction, and then the layer boundary and the layer thickness are obtained based on the concentration distribution information. The procedure of composition analysis in the thickness direction and the definition of the layer boundary and layer thickness of each layer are described below.

(1) Composition analysis in the thickness direction First, the cross section of the gas barrier film is observed with a transmission electron microscope, and the total thickness of the composite layer is measured. Next, the following measurement capable of elemental composition analysis in the depth direction is applied to obtain an element concentration distribution (concentration profile in the thickness direction) corresponding to the thickness position of the composite layer. Composition analysis methods applied at this time include electron energy loss spectroscopy (hereinafter referred to as EELS analysis), energy dispersive X-ray spectroscopy (hereinafter referred to as EDX analysis), and secondary ion mass spectrometry (hereinafter referred to as SIMS analysis). ), X-ray photoelectron spectroscopy (referred to as XPS analysis), and Auger electron spectroscopy (hereinafter referred to as AES analysis analysis), but EELS analysis is most preferable from the viewpoint of sensitivity and accuracy. Therefore, the EELS analysis is performed first, and the subsequent analysis (EELS analysis → SIMS analysis → AES analysis → XPS analysis → EDX analysis) is performed. To apply the data.

(2) Boundary between layers (2-1) Boundary between [A] layer and [B] layer Concentration of Al atom contained as a component of [A] layer and concentration of S atom contained as a component of [B] layer From the concentration profiles of the respective concentrations in the thickness direction, the position at which the Al atom concentration and the S atom concentration are equal is defined as the layer boundary.
(2-2) Boundary between [A] layer or [B] layer and [C] layer In the concentration profile in the thickness direction of Zn atoms contained as a component of the [A] layer or [B] layer, in the [A] layer Alternatively, a position where the concentration is 10% or less with respect to the maximum concentration of Zn atoms in the [B] layer is defined as a layer boundary.

  In addition, when a layer other than the [B] layer or the [C] layer and not containing Zn is adjacent to the [A] layer (2-2 ′), the [A] layer or the [[ In the case where a layer other than the C] layer and not containing Zn is adjacent (2-2 ″), the boundary of the layer is defined in the same manner.

(3) Definition of thickness of each layer (2) The distance between the boundaries of each layer determined at the boundary of each layer is defined as the thickness.

Hereinafter, the present invention will be specifically described based on examples. However, the present invention is not limited to the following examples.
[Evaluation method]
First, an evaluation method in each example and comparative example will be described. The number of evaluation n was n = 5 and the average value was obtained unless otherwise specified.

(1) Layer thickness Samples for cross-sectional observation were obtained by the FIB method using a microsampling system (Hitachi FB-2000A) (specifically, “Polymer Surface Processing” (by Satoshi Iwamori) p. 118-119). (Based on the method described in 1). Using a transmission electron microscope (H-9000UHRII, manufactured by Hitachi), the cross section of the observation sample was observed at an acceleration voltage of 300 kV, and the thicknesses of the [A] layer, [B] layer, and [C] layer of the casbarrier layer were measured.

(2) Average light transmittance Using a spectrophotometer UV-3150 (manufactured by Shimadzu Corporation), the light transmittance is measured every 5 nm in the wavelength range of 380 to 780 nm, and the average value of the obtained values is calculated. The average light transmittance was taken.

(3) Color tone Based on the CIE standard (1976), the b * value of the reflected color was measured using a spectrocolorimeter CM-2600d (manufactured by Konica Minolta Sensing Co., Ltd.). The light source was D65, and the measurement was performed at an angle of 2 °.

(4) Refractive index at a wavelength of 550 nm For a coating layer formed on a silicon wafer or quartz glass with a coater, using a high-speed spectrophotometer M-2000 (manufactured by JA Woollam), polarization of the reflected light of the coating layer The change in state was measured at an incident angle of 60 degrees, 65 degrees, and 70 degrees, and the refractive index at a wavelength of 550 nm was calculated by the analysis software WVASE32.

(5) Water vapor transmission rate Water vapor transmission rate measurement device (model name: DELTAPERRM (registered trademark)) manufactured by Technolox, UK, under conditions of a temperature of 40 ° C., a humidity of 90% RH, and a measurement area of 50 cm ² Was measured using. The number of samples was 2 samples per level, the number of measurements was 10 times for the same sample, and the average value was the water vapor transmission rate.

(6) Composition of [A] layer The composition analysis of the [A] layer was performed by ICP emission spectroscopic analysis (manufactured by SII Nanotechnology Inc., SPS4000). The contents of zinc atom, silicon atom, and aluminum atom in the sample were measured and converted to the atomic ratio. The oxygen atoms were calculated values based on the assumption that zinc atoms, silicon atoms, and aluminum atoms exist as zinc oxide (ZnO), silicon dioxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ), respectively.

(7) Composition of [B] layer The composition analysis of the [B] layer was performed by ICP emission spectroscopic analysis (manufactured by Seiko Denshi Kogyo Co., Ltd., SPS4000), and further based on this value, Rutherford backscattering method (Nisshin High Each element was quantitatively analyzed by using AN-2500 (Voltage Co., Ltd.) to determine the composition ratio of zinc sulfide and silicon dioxide. (8) Composition of [C] layer and aluminum oxide layer X-ray photoelectron spectroscopy ( By using the XPS method, the [C] layer has an atomic ratio of oxygen atoms to silicon atoms (O / Si ratio), and the aluminum oxide layer (comparative example) has an atomic ratio of oxygen atoms to aluminum atoms (O / Al). Ratio).

  The measurement conditions were as follows.

・ Device: Quantera SXM (manufactured by PHI)
Excitation X-ray: monochromic AlKα1,2
・ X-ray diameter 100 μm ・ Photoemission angle: 10 °
(9) Bending resistance See FIG. The gas barrier film was sampled to 100 mm × 140 mm, and a metal cylinder 5 having a diameter of 30 mm was fixed to the central portion on the surface of the gas barrier film 6 on which the gas barrier layer was formed, and the holding angle of the cylinder was 0 ° ( The sample was bent 100 times in a range in which the holding angle to the cylinder was 180 ° (in a state where the sample was folded back by the cylinder) from the state where the sample was flat. Bending resistance was determined using the water vapor transmission rate before and after the bending operation as an index. The water vapor transmission rate was evaluated by the method shown in (5) before and after the bending operation.
[Formation of [A] to [C] Layer]
([A] layer)
The surface of the polyethylene terephthalate film 7 (the surface on which the polyethylene terephthalate is exposed or the surface on which the [B] layer or the [C] layer is formed) is obtained using a winding type sputtering apparatus having the structure shown in FIG. On top, sputtering with argon gas and oxygen gas was performed using a sputtering target which is a mixed sintered material formed of zinc oxide, silicon dioxide and aluminum oxide, and the [A] layer shown in Table 1 was provided.

The specific operation is as follows. First, the composition mass ratio of zinc oxide / silicon dioxide / aluminum oxide is 77.0 / 20.0 / 3.0 (A (a) in Table 1) or 62.0 / 35.0 / 3. The polyethylene terephthalate film 7 is set on the unwinding roll 10 in the winding chamber 9 of the winding-type sputtering apparatus 8 in which the sputtering target sintered at 0 (Table 1 A (b)) is installed. And passed through the cooling drum 14 through the guide rolls 11, 12, and 13. Argon gas and oxygen gas are introduced with a partial pressure of oxygen gas of 10% so that the degree of vacuum is 2 × 10 ⁻¹ Pa, and an argon / oxygen gas plasma is generated by applying an input power of 4000 W from a DC power source, and sputtering is performed. Thus, an [A] layer was formed on the surface of the polyethylene terephthalate film 7. The thickness was adjusted by the film transport speed. Then, it wound up on the winding roll 19 through the guide rolls 16, 17, and 18.

([B] layer)
The surface of the polyethylene terephthalate film 7 (the surface on which the polyethylene terephthalate is exposed, or the surface on which the [A] layer or the [C] layer is formed) is obtained using a winding type sputtering apparatus having the structure shown in FIG. On top, sputtering by argon gas plasma was performed using a sputtering target which is a mixed sintered material formed of zinc sulfide and silicon dioxide, and a [B] layer shown in Table 2 was provided.

The specific operation is as follows. First, a sputtering target sintered with a zinc sulfide / silicon dioxide molar composition ratio of 85/15 (B (a) in Table 2) or 75/25 (B (b) in Table 2) is installed on the plasma electrode 15. In the take-up chamber 9 of the take-up type sputtering device 8, the polyethylene terephthalate film 7 was set on the take-up roll 10, unwound, and passed through the cooling drum 14 through the guide rolls 11, 12, 13. . Argon gas was introduced so that the degree of vacuum was 2 × 10 ⁻¹ Pa, and an argon gas plasma was generated by applying an input power of 500 W from a high-frequency power source. On the surface of the polyethylene terephthalate film 7 by sputtering, [B ] Layer was formed. The thickness was adjusted by the film transport speed. Then, it wound up on the winding roll 19 through the guide rolls 16, 17, and 18.

([C] layer)
Using a roll-up type chemical vapor deposition (hereinafter abbreviated as CVD) apparatus having the same structure as shown in FIG. 7, the surface of the polyethylene terephthalate film 7 (the [A] layer or the [B] layer was formed. On the surface), chemical vapor deposition using hexamethyldisiloxane as a raw material was performed to provide a [C] layer shown in Table 3. (Hereinafter, the apparatus in FIG. 7 will be described as a CVD apparatus. However, no sputter target is installed.)
The specific operation is as follows. In the take-up chamber 9 of the take-up type CVD apparatus 8, the polyethylene terephthalate film 7 was set on the take-up roll 10, unwound, and passed through the cooling drum 14 through the guide rolls 11, 12, and 13. Argon gas 0.5 L / min and hexamethyldisiloxane 70 cc / min were introduced so that the degree of vacuum was 2 × 10 ⁻¹ Pa, and plasma was generated by applying an input power of 500 W with a high frequency power source, and by CVD A [C] layer was formed on the surface of the polyethylene terephthalate film 7. The thickness was adjusted by the film transport speed. Then, it wound up on the winding roll 19 through the guide rolls 16, 17, and 18.

Example 1
As a transparent substrate, a polyethylene terephthalate film 7 having a thickness of 188 μm (“Lumirror (registered trademark)” U35 manufactured by Toray Industries, Inc .: an easy-adhesion layer is formed on one surface, and polyethylene terephthalate is exposed on the other surface. ), A B (a) layer having a zinc sulfide molar fraction of 0.85 was provided on the surface of the transparent substrate on which polyethylene terephthalate was exposed (B (a) layer thickness: 200 nm) did).

  Next, one A (a) layer was laminated on the B (a) layer (the thickness of the A (a) layer was 270 nm) to obtain a gas barrier film. The composition of the A (a) layer was such that the Zn atom concentration was 27.5 atom%, the Si atom concentration was 13.1 atom%, the Al atom concentration was 2.3 atom%, and the O atom concentration was 57.1 atom%.

  Next, a test piece having a length of 100 mm and a width of 140 mm was cut out from the obtained gas barrier film, and the average light transmittance, color tone, and bending resistance were evaluated. The results are shown in Table 4.

(Example 2)
A gas barrier film was obtained in the same manner as in Example 1 except that the B (b) layer was formed instead of the B (a) layer.

  As for the composition of the B (b) layer, the molar fraction of zinc sulfide was 0.75.

(Example 3)
An A (b) layer is formed instead of the B (a) layer (A (b) layer thickness: 240 nm), and B (a) is formed instead of the A (a) layer (B (a) layer The gas barrier film was obtained in the same manner as in Example 1 except that the thickness was 120 nm.

  The composition of the A (b) layer was such that the Zn atom concentration was 21.8 atom%, the Si atom concentration was 17.1 atom%, the Al atom concentration was 2.1 atom%, and the O atom concentration was 59.0 atom%.

Example 4
A gas barrier film was obtained in the same manner as in Example 1 except that the A (b) layer was formed instead of the A (a) layer (the thickness of the A (b) layer was 270 nm).

(Example 5)
A gas barrier film was obtained in the same manner as in Example 2 except that the A (b) layer was formed instead of the A (a) layer (the thickness of the A (b) layer was 280 nm).

(Example 6)
Except for changing the thickness of the A (a) layer from 270 nm to 120 nm, and then laminating one C layer on the A (a) layer (C layer thickness: 40 nm), the same as in Example 1. Thus, a gas barrier film was obtained. The composition (O / Si ratio) of the SiO ₂ layer was 1.6.

(Example 7)
The thickness of the B (a) layer was changed from 200 nm to 135 nm, and then the C layer was laminated on the A (a) layer (the thickness of the C layer was 45 nm), and further the A (b) layer was One layer is stacked on the second C layer (A (b) layer: 120 nm), and then the fourth layer is a C layer stacked on the A (b) layer (C layer thickness: 30 nm). The gas barrier film was obtained in the same manner as in Example 1.
(Comparative Example 1)
A gas barrier film was obtained in the same manner as in Example 1 except that the thickness of the B (a) layer was changed from 200 nm to 680 nm and the A (a) layer was not formed.
(Comparative Example 2)
A gas barrier film was formed in the same manner as in Example 1 except that the A (a) layer was formed instead of the B (a) layer (the thickness of the A (a) layer was 690 nm), and the A (a) layer was not formed. Got.
(Comparative Example 3)
A gas barrier film was obtained in the same manner as in Example 1 except that the C layer was formed in place of the B (a) layer (the thickness of the C layer was 750 nm) and the A (a) layer was not formed.
(Comparative Example 4)
Instead of a sputter target sintered with a zinc oxide / silicon dioxide / aluminum oxide composition mass ratio of 77.0 / 20.0 / 3.0 (A in Table 1), zinc oxide / aluminum oxide Gas barrier film in the same manner as in Example 1 except that the thickness of the layer formed using a sputter target sintered at a composition mass ratio of 97.0 / 3.0 (A (a) in Table 1) was 640 nm. Got. The composition (atomic concentration) of the film obtained by sputtering was such that the Zn atom concentration was 46.5 atom%, the Al atom concentration was 2.8 atom%, and the O atom concentration was 50.7 atom%.
(Comparative Example 5)
A gas barrier film was obtained in the same manner as in Example 1 except that the C layer was formed instead of the A (a) layer (the thickness of the C layer was 350 nm).
(Comparative Example 6)
An A (a) layer is formed instead of the B (a) layer (A (a) layer thickness: 200 nm), and a C layer is formed instead of the A (a) layer (C layer thickness: 150 nm). Except for the above, a gas barrier film was obtained in the same manner as in Example 1.
(Comparative Example 7)
Instead of a sputter target sintered at a zinc sulfide / silicon dioxide molar composition ratio of 85/15 (B (a) in Table 2), an aluminum oxide (Al ₂ O ₃ ) sputter target having a purity of 99.99% by mass A gas barrier film was obtained in the same manner as in Example 1 except that the thickness of the layer formed using was changed to 200 nm. The composition (O / Al ratio) of the aluminum oxide layer was 1.45.
(Comparative Example 8)
Instead of a sputter target sintered at a zinc sulfide / silicon dioxide molar composition ratio of 85/15 (B (a) in Table 2), an aluminum oxide (Al ₂ O ₃ ) sputter target having a purity of 99.99% by mass A gas barrier film was obtained in the same manner as in Example 3 except that the thickness of the layer formed using was changed to 200 nm. The composition (O / Al ratio) of the aluminum oxide layer was 1.45.

  Since the gas barrier film of the present invention has high gas barrier properties against oxygen gas, water vapor, etc., transparency, and heat resistance, for example, as a packaging material for foods, pharmaceuticals, etc., and as an electronic device member for thin TVs, solar cells, etc. Although it can be usefully used, the application is not limited to these.

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 [A] layer 3 [B] layer 4 [C] layer 5 Metal cylinder 6 Gas barrier film 8 Winding-type sputtering apparatus 9 Winding chamber 10 Unwinding roll 11 12, 13 Unwinding side guide roll 14 Cooling drum 15 Sputtering electrodes 16, 17, 18 Winding side guide roll 19 Winding roll

Claims (10)

A gas barrier film in which a composite layer including the following [A] layer and [B] layer is disposed on at least one surface of a transparent substrate.
[A] layer: a layer composed of a coexisting phase of zinc oxide-silicon dioxide-aluminum oxide [B] layer: a layer composed of a coexisting phase of zinc sulfide and silicon dioxide The [A] layer has a zinc (Zn) atom concentration of 20.0 to 40.0 atom%, a silicon (Si) atom concentration of 5.0 to 20.0 atom%, and aluminum (as measured by ICP emission spectroscopy). 2. The gas barrier film according to claim 1, wherein the Al) atomic concentration is 0.5 to 5.0 atom% and the oxygen (O) atomic concentration is 35.0 to 70.0 atom%. 3. The gas barrier film according to claim 1, wherein the [B] layer has a zinc sulfide mole fraction of 0.7 to 0.9 with respect to the total of zinc sulfide and silicon dioxide. The refractive index of the [A] layer is in the range of 1.5 to 1.8 at a wavelength of 550 nm, and the refractive index of the [B] layer is in the range of 2.0 to 2.4 at a wavelength of 550 nm. The gas barrier film according to any one of claims 1 to 3. The gas barrier film according to any one of claims 1 to 4, wherein the composite layer is a layer having the following [C] layer so as to be in contact with the [A] layer and / or the [B] layer.
[C] layer: silicon oxide layer The gas barrier film according to claim 5, wherein the thickness of the [C] layer is 5 to 40% of the total thickness of the [A] layer, the [B] layer, and the [C] layer. The gas barrier film according to claim 5 or 6, wherein the [C] layer has a thickness of 5 to 300 nm. The gas barrier film according to any one of claims 5 to 7, wherein a refractive index of the [C] layer is in a range of 1.43 to 1.50 at a wavelength of 550 nm. The gas barrier film according to claim 1, wherein the transparent substrate has a resin layer on at least the side having the composite layer. The composite layer has a transparent conductive layer containing any one of indium tin oxide (ITO), zinc oxide (ZnO), and aluminum-containing zinc oxide (Al / ZnO) on the surface not in contact with the transparent substrate. The gas barrier film according to any one of claims 1 to 9.

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