Method for manufacturing gas barrier films

Abstract

This gas barrier film is provided with an organic substrate and an inorganic transparent barrier layer provided on one side of the organic substrate, wherein the inorganic transparent barrier layer contains a barrier material as the primary component, and contains Kr and / or Xe.

Description

Technical Field

[0001] The present invention relates to a gas barrier film and a method for manufacturing the gas barrier film.

Background Art

[0002] Since the gas barrier film has high barrier properties, it is widely used for packaging of foods, industrial products, pharmaceuticals, etc., and substrates such as liquid crystal display elements, OLEDs (Organic Light Emitting Diodes), organic ELs (organic Electro-Luminescence), and solar cells.

[0003] Recently, in order to impart further functions to the gas barrier film, when laminating a functional layer such as a transparent conductive layer on the gas barrier film, it is important to laminate the functional layer with high precision. When the functional layer is laminated, if the gas barrier film is warped (curled), it becomes difficult to laminate the functional layer etc. accurately on the gas barrier film. Therefore, various studies have been made on the gas barrier film with suppressed warping.

[0004] As a gas barrier film with suppressed warping, for example, a gas barrier sheet having an anchor layer containing a polysiloxane polymer and a gas barrier layer containing silicon oxide and a conductive material on a substrate is disclosed (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the gas barrier sheet described in Patent Document 1 has the problem that, in order to prevent warping, it is necessary to have two layers, an anchor layer and a gas barrier layer, and in order to enhance the interaction between the anchor layer and the gas barrier layer, the materials constituting these layers are limited to materials containing Si.

[0007] Generally, gas barrier films utilize a gas barrier layer containing compounds such as Si-based, Zn-based, Sn-based, and Al-based compounds. It is desirable that the materials constituting the gas barrier layer be appropriately selected according to the gas barrier performance and application of the gas barrier film. Therefore, in order to promote the use of gas barrier films, there is a need for a method to suppress warping of gas barrier films without being limited by the materials constituting the gas barrier layer, such as the compounds mentioned above.

[0008] One aspect of the present invention aims to provide a gas barrier film that can suppress warping without being limited by the material constituting the gas barrier layer. [Means for solving the problem]

[0009] One embodiment of the gas barrier film according to the present invention comprises an organic substrate and an inorganic transparent barrier layer provided on one side of the organic substrate, wherein the inorganic transparent barrier layer mainly contains a barrier material and contains at least one of Kr and Xe.

[0010] Another embodiment of the method for manufacturing a gas barrier film according to the present invention is a method for manufacturing a gas barrier film as described above, wherein the inorganic transparent barrier layer is formed on an organic substrate by sputtering a barrier material containing at least one of Kr and Xe using a target containing Zn in a gas atmosphere containing at least one of Kr and Xe. [Effects of the Invention]

[0011] One embodiment of the gas barrier film according to the present invention can suppress warping without limiting the materials constituting the gas barrier layer. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic cross-sectional view showing the configuration of a gas barrier film according to an embodiment of the present invention. [Figure 2] This is an explanatory diagram for measuring the amount of warping of a gas barrier film. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described in detail below. For ease of understanding, the same reference numerals are used for identical components in each drawing, and redundant explanations are omitted. Furthermore, the scale of each component in the drawings may differ from the actual scale. In this specification, the "~" indicating a numerical range means that the values ​​before and after it are included as the lower and upper limits, respectively, unless otherwise specified.

[0014] <Gas barrier film> A gas barrier film according to an embodiment of the present invention will now be described. Figure 1 is a schematic cross-sectional view showing the configuration of the gas barrier film according to this embodiment. As shown in Figure 1, the gas barrier film 1 according to this embodiment comprises an organic substrate 10 and an inorganic transparent barrier layer 20 provided on the upper surface 10a side of the organic substrate 10, the inorganic transparent barrier layer 20 containing a barrier material as its main component and containing at least one of krypton (Kr) and xenon (Xe) as an additive component.

[0015] The gas barrier film 1 can suppress warping (curling) regardless of the main component material of the inorganic transparent barrier layer 20, by including at least one of Kr and Xe as an additive in the inorganic transparent barrier layer 20.

[0016] In this specification, the thickness direction (vertical direction) of the gas barrier film 1 is defined as the Z-axis direction, and the lateral direction (horizontal direction) orthogonal to the thickness direction is defined as the X-axis direction. The side of the inorganic transparent barrier layer 20 in the Z-axis direction is the +Z-axis direction, and the side of the organic substrate 10 is the -Z-axis direction. In the following description, for the sake of convenience, the +Z-axis direction is referred to as up or upward, and the -Z-axis direction is referred to as down or downward, but it does not represent a universal up-and-down relationship.

[0017] The main component means that the content of the barrier material is 95 atm% or more, preferably 97 atm% or more, and more preferably 99 atm% or more.

[0018] The organic substrate 10 is a plate-shaped member or film having two opposing main surfaces, and is the substrate on which the inorganic transparent barrier layer 20 is provided. The organic substrate 10 is provided such that the lower surface of the inorganic transparent barrier layer 20 contacts the upper surface (main surface) 10a thereof.

[0019] As the material for forming the organic substrate 10, a polymer can be used.

[0020] Examples of the polymer include acrylic resin, polyester resin, polyolefin resin, cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyether ether ketone, polyimide, etc. These may be used alone or in combination of two or more.

[0021] Examples of the acrylic resin include polycarbonate (PC), polymethyl methacrylate (PMMA), polyethyl methacrylate, polybutyl acrylate, etc.

[0022] Examples of the polyester resin include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, isophthalate copolymer, etc.

[0023] Examples of polyolefin resins include polyethylene (PE), polypropylene (PP), polybutylene (PB), polypentene, and cycloolefin polymers.

[0024] Among these, polyester resins and polyolefin resins are preferred from the viewpoint of transparency. More preferably, PET and cycloolefin polymer resins are mentioned.

[0025] The thickness of the organic substrate 10 is not particularly limited and can be any appropriate thickness depending on the application of the gas barrier film 1, the material of the organic substrate 10, etc. The thickness of the organic substrate 10 is preferably 10 μm to 400 μm, and more preferably 20 μm to 200 μm.

[0026] In this specification, the thickness of the organic substrate 10 refers to the length perpendicular to the main surface of the organic substrate 10. The thickness of the organic substrate 10 may be, for example, the thickness measured at any point in the cross-section of the organic substrate 10, or it may be the average of several measurements taken at any point. Hereafter, the definition of thickness will be the same for other components.

[0027] The organic substrate 10 preferably has an absorption rate of, for example, 4% or less for light with a wavelength of 380 nm. The absorption rate of the organic substrate 10 is, for example, the catalog value. Absorption of light on the short wavelength side is due to the band gap. If the band gap is close to the short wavelength component of visible light, absorption in the short wavelength range may occur. On the other hand, if the band gap is wide, the absorption edge on the short wavelength side shifts to the short wavelength side, so the absorption of visible light can be reduced. That is, the transparency of the organic substrate 10 is improved. Therefore, in this embodiment, regarding the absorption rate of the organic substrate 10, we focus on the absorption rate for light with a wavelength of 380 nm, which is located in the short wavelength region of visible light.

[0028] The organic substrate 10 may have, for example, an easy-adhesion layer (not shown) on its lower main surface.

[0029] As shown in Figure 1, the inorganic transparent barrier layer 20 is provided on the upper surface 10a of the organic substrate 10.

[0030] The inorganic transparent barrier layer 20 may include a transparent oxide film, and is preferably composed of a transparent oxide film.

[0031] The transparent oxide film preferably contains a barrier material as its main component, along with at least one of Kr and Xe as an additive component, and has transmittance (light transmission) to visible light.

[0032] Furthermore, "light transmittance" means that when visible light (light with a wavelength of 380 nm to 780 nm) is irradiated from one main surface side of the transparent oxide film, it has the ability to pass through the interior of the transparent oxide film. The visible light transmittance of the transparent oxide film is preferably 60% or more, more preferably 75% or more, and even more preferably 90% or more. The visible light transmittance can be determined as the average value of the transmittance at each wavelength when measured using a spectrophotometer at wavelengths of 380 nm to 780 nm.

[0033] The barrier material preferably contains at least one component selected from the group consisting of zinc (Zn), silicon (Si), tin (Sn), magnesium (Mg), and aluminum (Al), and at least one of oxygen and nitrogen. That is, the barrier material preferably contains an oxide containing at least one component selected from the group consisting of Zn, Si, Sn, Mg, and Al.

[0034] The barrier material is more preferably substantially composed of an oxide containing the above components, and even more preferably composed solely of an oxide containing the above components. "Substantially" means that, in addition to the oxide containing the above components and any impurities that may inevitably be present during the manufacturing process, it may also contain unavoidable impurities. The content of unavoidable impurities is, for example, 0.02 at% or less, more preferably 0.01 at% or less.

[0035] Specifically, barrier materials that can be used include oxides mainly composed of Si, composite oxides containing Zn, Al, Si, and oxygen, composite oxides containing Zn, Sn, and oxygen, and composite oxides containing Zn, Sn, Mg, and oxygen.

[0036] The barrier material is preferably at least one of a Zn-based material and a Si-based material, containing at least one of Zn and Si as essential elements, because it is highly transparent in its oxide state and easy to adjust to increase water vapor permeability by mixing with other elements.

[0037] The Zn content in the barrier material is preferably 0 at% to 90 at%, more preferably 10 at% to 80 at%, and even more preferably 20 at% to 70 at%.

[0038] The Si content is preferably 0 at% to 90 at%, more preferably 10 at% to 80 at%, and even more preferably 20 at% to 70 at%.

[0039] The Sn content is preferably 0 at% to 90 at%, more preferably 10 at% to 80 at%, and even more preferably 20 at% to 70 at%.

[0040] The Mg content is preferably 0 at% to 40 at%, more preferably 3 at% to 30 at%, and even more preferably 5 at% to 25 at%.

[0041] The Al content is preferably 0 at% to 40 at%, more preferably 3 at% to 30 at%, and even more preferably 5 at% to 25 at%.

[0042] The amount of barrier material contained in the transparent oxide film is not particularly limited and can be arbitrarily determined as appropriate, as long as the absorption rate to light (light with a wavelength of 380 nm) and the water vapor transmittance can be kept low.

[0043] The main components contained in the transparent oxide film can be identified and quantified, for example, using an X-ray fluorescence analyzer.

[0044] The content of impurities in the transparent oxide film is preferably greater than 0 at% and 0.2 at% or less, more preferably between 0.02 at% and 0.15 at%, and even more preferably between 0.04 at% and 0.10 at%. If the content of impurities is within the above preferred range, the amount that penetrates into the crystal lattice of the barrier material constituting the inorganic transparent barrier layer 20 can be suppressed, thereby suppressing film stress in the inorganic transparent barrier layer 20 and preventing warping of the inorganic transparent barrier layer 20. In addition, since the content of barrier material in the inorganic transparent barrier layer 20 can be kept high, the durability of the inorganic transparent barrier layer 20 can be increased and the adhesion to the organic substrate 10 can be improved.

[0045] The amount of impurities can be measured, for example, by Rutherford backscattering analysis (RBS) using a Pelletron 3SDH (manufactured by NEC Corporation) as the measuring instrument.

[0046] The thickness of the inorganic transparent barrier layer 20 is preferably 10 nm to 500 nm, more preferably 15 nm to 450 nm, and even more preferably 30 nm to 400 nm. If the thickness of the inorganic transparent barrier layer 20 is within the above preferred range, the inorganic transparent barrier layer 20 can perform its function. Furthermore, even if the inorganic transparent barrier layer 20 contains impurities, the occurrence of cracks and other defects in the inorganic transparent barrier layer 20 can be reduced, suppressing a decrease in barrier function, and preventing warping of the inorganic transparent barrier layer 20. The thickness of the inorganic transparent barrier layer 20 can be measured in the same way as the thickness of the organic substrate 10.

[0047] The film density of the inorganic transparent barrier layer 20 can be set as appropriate and is not particularly limited as long as it is within a range that can exhibit high gas barrier properties.

[0048] The gas barrier properties of the inorganic transparent barrier layer 20 can be evaluated by measuring its water vapor transmission rate. The water vapor transmission rate can be measured at 25±0.5℃ and 90±2%RH according to JIS K 7129-1992. For example, the water vapor transmission rate is 5.0 × 10⁻⁶. -2 (g / m 2 Preferably less than or equal to 4.0 × 10 -2 (g / m 2 / day) or less is more preferable, 3.5 × 10 -2 (g / m 2 A value of less than or equal to ( / day) is even more preferable. If the water vapor transmission rate of the gas barrier film 1 is less than or equal to the above preferred upper limit, the gas barrier film 1 has excellent barrier properties, particularly water vapor barrier properties. The lower limit of the water vapor transmission rate of the gas barrier film 1 is not particularly limited.

[0049] The transparency of the gas barrier film 1 can be evaluated by measuring its absorptivity to light at a wavelength of 380 nm. The absorptivity of the gas barrier film 1 to light at a wavelength of 380 nm is preferably 12% or less, more preferably 10% or less, and even more preferably 7% or less. If the absorptivity of the gas barrier film 1 to light at a wavelength of 380 nm is below the above preferred upper limit, the gas barrier film 1 can have excellent transparency. The lower limit of the absorptivity of the gas barrier film 1 to light at a wavelength of 380 nm is not particularly limited. Furthermore, the method for measuring the absorptivity is not particularly limited, and any measurement method can be used as appropriate.

[0050] Next, an example of a method for manufacturing the gas barrier film 1 will be described.

[0051] The atmosphere in which the organic substrate 10 is placed is a gas atmosphere containing at least one of Kr and Xe. Then, in the gas atmosphere containing at least one of Kr and Xe, the barrier material constituting the main component of the inorganic transparent barrier layer 20 is sputtered onto the upper surface 10a of the organic substrate 10, thereby forming an inorganic transparent barrier layer 20 that contains at least one of Kr and Xe as an admixture while the barrier material is the main component. By laminating the inorganic transparent barrier layer 20 onto the upper surface 10a of the organic substrate 10, a gas barrier film 1 is obtained.

[0052] Methods for forming the inorganic transparent barrier layer 20 include, for example, dry processes such as sputtering and vapor deposition, and wet processes such as plating. If a dry process is used as the method for forming the inorganic transparent barrier layer 20, a thin inorganic transparent barrier layer 20 can be easily formed. By using sputtering as a dry process for forming the inorganic transparent barrier layer 20, a high-density inorganic transparent barrier layer 20 can be formed while the barrier material is the main component and at least one of Kr and Xe is included as an admixture in the main component.

[0053] When sputtering is used to form the inorganic transparent barrier layer 20, the deposition chamber of the sputtering apparatus is kept in an inert gas atmosphere. If the inert gas contains at least one of Kr and Xe, at least one of the Kr atoms and Xe atoms will penetrate into the crystal lattice of the barrier material contained in the inorganic transparent barrier layer 20, but they will penetrate less easily than Ar atoms, which are another type of inert gas. Therefore, film stress in the inorganic transparent barrier layer 20 is suppressed, and warping of the inorganic transparent barrier layer 20 caused by film stress can be suppressed. Thus, by depositing the inorganic transparent barrier layer 20 by sputtering in a gas atmosphere containing at least one of Kr and Xe, the inorganic transparent barrier layer 20 can be deposited while suppressing warping.

[0054] The organic substrate 10 is placed on a deposition plate that will serve as the anode in the deposition chamber of the sputtering apparatus. The deposition plate may, for example, be rotatable. Once the organic substrate 10 is placed on the deposition plate, an inorganic transparent barrier layer 20 can be deposited on the organic substrate 10 in a batch manner.

[0055] Furthermore, the organic substrate 10 may be wound around a drum roll, which is a film-forming roll, instead of a film-forming plate, as an anode. By placing the drum roll in the film-forming chamber, it becomes possible to continuously deposit an inorganic transparent barrier layer 20 on the organic substrate 10 while transporting the organic substrate 10 in a roll-to-roll manner.

[0056] Furthermore, if the organic substrate 10 includes, for example, an easy-adhesion layer, the easy-adhesion layer is brought into contact with the anode.

[0057] Multiple or single targets containing the barrier material as the main component of the inorganic transparent barrier layer 20 are used as cathodes. Multiple or single targets are arranged opposite the film deposition plate with a gap between them.

[0058] When multiple targets are used as cathodes, each target contains a different type of material that constitutes the barrier material in the inorganic transparent barrier layer 20. For example, when using multiple targets, a target containing Zn, a target containing Si or Sn, and a target containing Al or Mg can be used. In addition, each target may be a metal oxide target containing oxygen. The multiple targets are preferably placed in the deposition chamber at intervals from each other. During sputtering, the power applied to each target is adjusted according to the type of barrier material contained in the inorganic transparent barrier layer 20, thereby adjusting the atomic ratio of the respective materials constituting the inorganic transparent barrier layer 20.

[0059] When a single target is used as the cathode, the single target contains the barrier material included in the inorganic transparent barrier layer 20. As an example of using a single target, an alloy target can be used in which the atomic ratios of the barrier materials included in the inorganic transparent barrier layer 20 are adjusted. For example, an alloy target containing Zn, Si or Sn, and Al or Mg can be used. The alloy target may be a metal oxide target containing the barrier material and oxygen.

[0060] At least one of Kr gas and Xe gas is supplied as the sputtering gas to the deposition chamber of the sputtering apparatus, creating a gas atmosphere in the deposition chamber that contains at least one of Kr and Xe. In addition to at least one of Kr gas and Xe gas, oxygen gas may also be supplied to the deposition chamber as the sputtering gas, creating a gas atmosphere in the deposition chamber that contains at least one of Kr and Xe and oxygen. At least one of Kr gas and Xe gas may be supplied to the deposition chamber, a mixed gas containing at least one of Kr gas and Xe gas and oxygen gas may be supplied, or at least one of Kr gas and Xe gas and oxygen gas may be supplied separately.

[0061] The vacuum level in the deposition chamber is preferably adjusted to 0.1 Pa to 2.0 Pa, more preferably to 0.15 Pa to 0.8 Pa, and even more preferably to 0.2 Pa to 0.6 Pa. If the vacuum level in the deposition chamber is within the above preferred range, the gas barrier properties of the inorganic transparent barrier layer 20 can be enhanced. In addition, the amount of Kr atoms or Xe atoms that penetrate into the crystal lattice of the barrier material contained in the inorganic transparent barrier layer 20 can be suppressed, thereby suppressing film stress and reducing warping of the resulting gas barrier film 1. At this time, the pressure in the mixed gas atmosphere during sputtering is preferably 0.10 Pa to 2.00 Pa, more preferably to 0.15 Pa to 0.80 Pa, and even more preferably to 0.20 Pa to 0.60 Pa.

[0062] In a mixed gas atmosphere containing at least one of Kr and Xe and oxygen, the ratio of the flow rate of oxygen to the total flow rate of at least one of Kr and Xe and oxygen can be appropriately selected depending on the type of gas, the oxygen content contained in the barrier material, etc. For example, it is preferably 0.1% to 20%, and more preferably 1% to 10%. If the ratio of the flow rate of oxygen to the total flow rate of at least one of Kr and Xe and oxygen is within the above preferred range, when forming an inorganic transparent barrier layer 20 by sputtering on an organic substrate 10 using one or more targets containing the barrier material, even if Kr atoms or Xe atoms penetrate into the crystal lattice of the barrier material contained in the inorganic transparent barrier layer 20, the amount of penetration can be suppressed. Therefore, it is possible to suppress the occurrence of film stress and warping in the inorganic transparent barrier layer 20.

[0063] As described above, the gas barrier film 1 according to this embodiment comprises an organic substrate 10 and an inorganic transparent barrier layer 20, the inorganic transparent barrier layer 20 mainly containing a barrier material and containing at least one of Kr and Xe as an admixture. As a result, the gas barrier film 1 can reduce the film stress of the inorganic transparent barrier layer 20. Furthermore, because the film stress generated in the inorganic transparent barrier layer 20 can be reduced, it is not necessary to separately provide an anchor layer between the organic substrate 10 and the inorganic transparent barrier layer 20 to suppress warping of the inorganic transparent barrier layer 20. Therefore, the barrier material included in the inorganic transparent barrier layer 20 does not need to be selected considering the material that forms the anchor layer. For example, when the anchor layer is siloxane-based, the inorganic transparent barrier layer 20 laminated on the anchor layer is limited to a material containing Si that readily interacts with the C contained in the anchor layer. Since the gas barrier film 1 does not require an anchor layer between the organic substrate 10 and the inorganic transparent barrier layer 20, the limitations on the types of barrier materials included in the inorganic transparent barrier layer 20 can be reduced. Therefore, the gas barrier film 1 can suppress warping without requiring an anchor layer to be provided between the organic substrate 10 and the inorganic transparent barrier layer 20 to relieve stress on the inorganic transparent barrier layer 20, thus preventing warping regardless of the barrier material contained in the inorganic transparent barrier layer 20.

[0064] Because the gas barrier film 1 can suppress warping, other functional layers can be precisely attached to the gas barrier film 1. Therefore, the gas barrier film 1 can maintain excellent barrier properties over a long period of time.

[0065] The amount of warpage of the gas barrier film 1 can be determined by calculating the average vertical height between the surface of the substrate in contact with the gas barrier film 1 and each corner of the gas barrier film 1 when the gas barrier film 1 is placed on the substrate with the convex side of the gas barrier film 1 facing downwards. For example, as shown in Figure 2, if the gas barrier film 1 is formed into a rectangle in plan view, the amount of warpage of the gas barrier film 1 is taken as the average vertical height between the surface of the gas barrier film 1 that is in contact with the substrate 2 and the four corners 1a of the gas barrier film 1.

[0066] Furthermore, since the gas barrier film 1 does not require a separate anchor layer between the organic substrate 10 and the inorganic transparent barrier layer 20 to suppress warping in the inorganic transparent barrier layer 20, it can be manufactured simply and manufacturing costs can be reduced.

[0067] The gas barrier film 1 can have the total content of Kr and Xe in the inorganic transparent barrier layer 20 be greater than 0 at% and less than or equal to 0.2 at%. This ensures that film stress in the inorganic transparent barrier layer 20 is reliably suppressed, and therefore the gas barrier film 1 can more reliably suppress warping.

[0068] The gas barrier film 1 may include an inorganic transparent barrier layer 20 containing an oxide with at least one component selected from the group consisting of Si, Zn, Sn, Al, and Mg. This allows the gas barrier film 1 to exhibit high gas barrier properties while suppressing warping.

[0069] The gas barrier film 1 allows the thickness of the inorganic transparent barrier layer 20 to be between 10 nm and 500 nm. This enables the gas barrier film 1 to be made thinner while reducing film stress and suppressing warping.

[0070] The gas barrier film 1 can achieve an arithmetic mean roughness Ra of the inorganic transparent barrier layer 20 of 0.2 nm to 2.0 nm. As a result, the gas barrier film 1 can have more stable and higher gas barrier properties.

[0071] Because the gas barrier film 1 has the above-described properties, it can be suitably used in, for example, image display devices, solar cells, and the like. Examples of image display devices include organic EL displays and liquid crystal displays. Examples of solar cells include flexible solar cells. [Examples]

[0072] The embodiments will be described in more detail below with reference to examples, but the embodiments are not limited to these examples. Examples 1-1, 2-1, 3-1, and 4-1 are examples, while the other examples are comparative examples.

[0073] <Example 1-1> [Manufacturing of gas barrier film 1] A polyethylene terephthalate (PET) film (thickness: 125 μm) was placed on a deposition plate in the deposition chamber of a sputtering apparatus as an organic substrate. Next, a target made of AlZnSiOx, in which ZnO, Al2O3, and SiO2 were adjusted to a mass ratio of 77 wt% / 3 wt% / 20 wt%, was placed in the deposition chamber of the sputtering apparatus. After evacuating the deposition chamber, Kr gas and O2 gas (Kr gas:O2 gas = 98:2) were introduced into the deposition chamber to create a mixed gas atmosphere of Kr and O2. Subsequently, 100 W of power was applied to the target from a DC power supply to deposit an inorganic transparent barrier layer with a thickness of 100 nm on one main surface of the PET film, thereby manufacturing a gas barrier film. The total thickness of the gas barrier film was 100 nm.

[0074] (Kr content in the inorganic transparent barrier layer) Furthermore, a sample of a gas barrier film was prepared under the same conditions as the gas barrier film. The Kr content, an impurity component in the gas barrier film sample, was measured using Rutherford backscattering analysis (RBS) with a Pelletron 3SDH (manufactured by NEC Corporation) based on the measurement conditions and evaluation criteria described below. A Kr content greater than 0 at% and 0.2 at% or less was considered to be a suitable Kr content. The measurement results for the Kr content are shown in Table 1. ((Measurement conditions)) • Incident ion: 4He ++ • Incident energy: 2300 keV ·Incidence angle: 0deg ·Scattering angle: 108deg • Sample current: 24nA • Beam diameter: 2mmφ • In-plane rotation: None ·Irradiation amount: 80μC

[0075] [Evaluation of characteristics] The amount of warpage and water vapor transmission rate of the gas barrier film were measured and evaluated.

[0076] (Amount of curvature) The fabricated gas barrier film was cut to a size of 10 cm square in plan view, and the cut gas barrier film was placed on a flat plate with the inorganic transparent barrier layer facing downwards. At this time, the temperature was room temperature (23°C). After 1 minute, each of the four corners of the gas barrier film curled up, and the amount of curl at each corner, i.e., the height in the vertical direction between the mounting surface of the flat plate and each corner, was measured, and the amount of curl of the gas barrier film was determined by calculating the average of these values ​​(see Figure 2). If the amount of curl was 2.5 mm or less, the curl of the gas barrier film was evaluated as good. The measurement results of the amount of curl are shown in Table 1.

[0077] (Water vapor transmission rate) Temperature 40℃, humidity 90%RH, measurement area 50cm2 Under these conditions, the water vapor transmission rate of the gas barrier film was measured using a water vapor transmission rate measuring device (DELTAPERM, manufactured by Technolocks Co., Ltd.) to evaluate its gas barrier properties. The measurement results are shown in Table 1.

[0078] <Example 1-2> In Example 1-1, the procedure was the same as in Example 1-1, except that the mixing ratio of Kr gas and O2 gas was changed to alter the Kr content of the inorganic transparent barrier layer as shown in Table 1. The Kr content was less than 0.02 at%, which is the detection limit measurable by Pelletron 3SDH (manufactured by NEC Corporation), and was evaluated as 0.

[0079] [Examples 2-1 and 2-2] In Example 1-1, the procedure was the same as in Example 1-1, except that the type of organic substrate was changed from PET film to COP film (thickness: 40 μm). The Kr content in Example 2-2 was less than the detection limit of 0.02 at%, as in Example 1-2, and was evaluated as 0.

[0080] [Examples 3-1 and 3-2] In Example 1-1, the sputtering target was changed to a sputtering target made of ZnSnOx, in which ZnO and SnO2 were adjusted to a mass ratio of 39.1 wt% / 60.9 wt%, and the type of inorganic transparent barrier layer was changed from AlZnSiOx to ZnSnOx. The procedure was otherwise the same as in Example 1-1. The Kr content in Example 3-2 was less than the detection limit of 0.02 at%, as in Example 1-2, and was evaluated as 0.

[0081] [Examples 4-1 and 4-2] In Example 1-1, the sputtering target was changed to a sputtering target made of ZnSnMgOx, in which ZnO, SnO2, and MgO were adjusted to a mass ratio of 35.5 wt% / 53.8 wt% / 10.7 wt%, and the type of inorganic transparent barrier layer was changed from AlZnSiOx to ZnSnMgOx. Otherwise, the procedure was the same as in Example 1-1. The Kr content in Example 4-2 was less than the detection limit of 0.02 at%, as in Example 1-2, and was evaluated as 0.

[0082] Table 1 shows the type of organic substrate, the type of main component of the inorganic transparent barrier layer, the measurement results of the Kr content of the inorganic transparent barrier layer, and the measurement results of the warpage and water vapor transmission rate of the gas barrier film for each example.

[0083] [Table 1]

[0084] Table 1 confirms that Examples 1-1, 2-1, 3-1, and 4-1 were able to reduce the amount of warping and water vapor transmission rate compared to Examples 1-2, 2-2, 3-2, and 4-2, respectively.

[0085] Therefore, unlike the gas barrier films in the other examples, the gas barrier films of Examples 1-1, 2-1, 3-1, and 4-1 can suppress warping regardless of the material of the gas barrier layer by setting the Kr content to a range greater than 0 at% and 0.2 at% or less. Thus, the gas barrier films can stably exhibit excellent gas barrier properties.

[0086] As described above, embodiments have been explained, but these embodiments are presented as examples only, and the present invention is not limited by these embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, and modifications are possible without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents.

[0087] This application claims priority based on Japanese Patent Application No. 2021-051537, filed with the Japan Patent Office on March 25, 2021, and the entire contents of Japanese Patent Application No. 2021-051537 are incorporated herein by reference. [Explanation of symbols]

[0088] 1. Gas barrier film 10 Organic substrate 20 Inorganic transparent barrier layer

Claims

1. Organic substrate and A method for manufacturing a gas barrier film, comprising an inorganic transparent barrier layer provided on one side of the organic substrate, In a gas atmosphere containing at least one of Kr and Xe, the inorganic transparent barrier layer is formed on an organic substrate by sputtering a barrier material containing at least one of Kr and Xe using a target containing Zn. A method for producing a gas barrier film, wherein the inorganic transparent barrier layer mainly contains a barrier material and contains at least one of Kr and Xe.

2. The method for producing a gas barrier film according to claim 1, wherein the total content of Kr and Xe in the inorganic transparent barrier layer is greater than 0 at% and less than or equal to 0.2 at%.

3. The method for producing a gas barrier film according to claim 1 or 2, wherein the inorganic transparent barrier layer comprises an oxide having at least one component selected from the group consisting of Zn, Si, Sn, Al, and Mg.

4. A method for manufacturing a gas barrier film according to any one of claims 1 to 3, wherein the thickness of the inorganic transparent barrier layer is 10 nm to 500 nm.

5. A method for producing a gas barrier film according to any one of claims 1 to 4, wherein the arithmetic mean roughness Ra of the inorganic transparent barrier layer is 0.2 nm to 2.0 nm.

6. A method for manufacturing a gas barrier film according to any one of claims 1 to 4, wherein the vacuum level is 0.1 Pa to 2.0 Pa.

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