JP2023050695A - Gas barrier film and method for producing the same, and polarizing plate with gas barrier layer and image display device - Google Patents

Abstract

To provide a gas barrier film which has excellent transparency and can secure gas barrier properties even when exposed to a high-temperature and high-humidity environment while suppressing the generation of ammonia and a method for producing the same, and to provide a polarizing plate with a gas barrier layer using the gas barrier film and an image display device.SOLUTION: There is provided a gas barrier film 10 which has a transparent film base material 11 and a gas barrier layer 12. The gas barrier layer 12 has a silicon oxynitride layer 13. A composition of a silicon oxynitride contained in the silicon oxynitride layer 13 is expressed by the general formula SiOxNy. The x and y of the general formula SiOxNy satisfy a relation of 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30. In a Si2p spectrum of the silicon oxynitride layer 13, when the area of a region between a Si2p spectral curve and a baseline is defined as S1 and the area of a peak derived from Si-Si bonding is defined as S2, a relation 0.05≤S2/S1≤0.30 is satisfied.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a gas barrier film, a method for producing the same, a polarizing plate with a gas barrier layer, and an image display device.

2. Description of the Related Art As image display devices become lighter, thinner, and more flexible, resin film substrates have come to be used instead of glass substrates. Since resin films have higher permeability to gases such as water vapor and oxygen than glass, it has been proposed to use a gas barrier film having a gas barrier layer for the purpose of suppressing deterioration of display elements caused by these gases. there is

An organic EL element may have defects called "dark spots" due to the intrusion of even a small amount of moisture, and high gas barrier properties (water vapor blocking properties) are required. Silicon nitride (SiN) and silicon oxynitride (SiON) are known as materials having excellent gas barrier properties.

For example, Patent Document 1 proposes a gas barrier film including a silicon nitride layer and a silicon oxide layer as a gas barrier film having excellent transparency and flexibility.

WO2019/187978

In a gas barrier film using a nitrogen-containing layer (more specifically, a silicon nitride layer, a silicon oxynitride layer, etc.) as a gas barrier layer, ammonia (ammonia gas) can be generated from the nitrogen-containing layer in a humidified environment. This has been clarified by the studies of the inventors. Ammonia generated from the nitrogen-containing layer reacts with, for example, moisture in the air to produce ammonium ions and hydroxide ions, which may corrode the device.

With only the technique disclosed in Patent Document 1, it is difficult to obtain a gas barrier film that can suppress the generation of ammonia, can ensure gas barrier properties even when exposed to a high-temperature and high-humidity environment, and has excellent transparency.

The present invention has been made in view of the above problems, and its object is to suppress the generation of ammonia while ensuring gas barrier properties even when exposed to a high-temperature and high-humidity environment, and to provide a gas barrier with excellent transparency. An object of the present invention is to provide a film, a method for producing the same, and a polarizing plate with a gas barrier layer and an image display device using the gas barrier film.

A gas barrier film according to the present invention has a transparent film substrate and a gas barrier layer directly or indirectly arranged on at least one main surface of the transparent film substrate. The gas barrier layer has a silicon oxynitride layer containing oxygen, nitrogen and silicon as constituent elements. The composition of silicon oxynitride contained in the silicon oxynitride layer is represented by the general formula SiO _x N _y . x and y in the general formula SiO _x N _y satisfy the relationships of 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30. In the Si2p spectrum of the silicon oxynitride layer obtained by X-ray photoelectron spectroscopy, the area of the region between the Si2p spectrum curve and the baseline in the range of binding energy 95 eV or more and 110 eV or less is defined as S1, and the waveform is obtained from the Si2p spectrum When the area of the peak derived from the Si—Si bond separated by the analysis is defined as S2, the relationship 0.05≦S2/S1≦0.30 is satisfied.

In one embodiment of the gas barrier film according to the present invention, S2/S1 is 0.15 or more and 0.30 or less.

In one embodiment of the gas barrier film according to the present invention, x/y is 2.00 or less.

In one embodiment of the gas barrier film according to the present invention, the silicon oxynitride layer has a thickness of 10 nm or more and 200 nm or less.

The gas barrier film according to one embodiment of the present invention further has a hard coat layer arranged between the transparent film substrate and the gas barrier layer.

The gas barrier film according to one embodiment of the present invention further has an adhesive layer disposed on the side of the gas barrier layer opposite to the transparent film substrate side.

The method for producing a gas barrier film according to the present invention is a suitable method for producing the above-described gas barrier film according to the present invention. A method for producing a gas barrier film according to the present invention comprises a step of introducing trisilylamine, a nitrogen source and an oxygen source into a chamber of a film forming apparatus to form the silicon oxynitride layer by chemical vapor deposition. .

A polarizing plate with a gas barrier layer according to the present invention includes the gas barrier film according to the present invention and a polarizer.

An image display device according to the present invention includes the gas barrier film according to the present invention or the gas barrier layer-attached polarizing plate according to the present invention, and an image display cell.

In one embodiment of the image display device according to the present invention, the image display cell includes an organic EL element.

According to the present invention, a gas barrier film that suppresses the generation of ammonia, can ensure gas barrier properties even when exposed to a high temperature and high humidity environment, and has excellent transparency, a method for producing the same, and a gas barrier film using the gas barrier film. A polarizing plate with a gas barrier layer and an image display device can be provided.

1 is a cross-sectional view showing an example of a gas barrier film according to the present invention; FIG. FIG. 2 is a diagram showing an example of the result of analyzing the silicon oxynitride layer of the gas barrier film according to the present invention by X-ray photoelectron spectroscopy. FIG. 4 is a cross-sectional view showing another example of the gas barrier film according to the present invention; FIG. 4 is a cross-sectional view showing another example of the gas barrier film according to the present invention; FIG. 4 is a cross-sectional view showing another example of the gas barrier film according to the present invention; FIG. 4 is a cross-sectional view showing another example of the gas barrier film according to the present invention; BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows an example of the polarizing plate with a gas barrier layer which concerns on this invention. It is a sectional view showing an example of an image display device concerning the present invention.

Preferred embodiments of the present invention are described below. First, the terms used in this specification will be explained. The number average primary particle diameter of the particles is the circle of 100 primary particles measured using a scanning electron microscope and image processing software (e.g., "ImageJ" manufactured by the National Institutes of Health), unless otherwise specified. It is a number average value of equivalent diameters (Heywood diameter: diameter of a circle having the same area as the projected area of primary particles).

The "principal surface" of a layered product (more specifically, a transparent film substrate, a gas barrier layer, a silicon oxynitride layer, a hard coat layer, an adhesive layer, a polarizer, etc.) point to the face The thickness of the layered material is obtained by observing a cross-section of the layer cut in the thickness direction with an electron microscope, randomly selecting 10 measurement points from the cross-sectional image, and measuring the thickness of the selected 10 measurement points. is the arithmetic mean of 10 measurements.

"Refractive index" refers to the refractive index for light with a wavelength of 550 nm in an atmosphere at a temperature of 23°C.

The flow rate unit "sccm (Standard Cubic Centimeter per Minute)" is the flow rate unit "mL/min" under standard conditions (temperature: 0°C, pressure: 101.3 kPa).

Hereinafter, X-ray photoelectron spectroscopy may be referred to as "XPS". A spectrum obtained by XPS is sometimes referred to as an "XPS spectrum". Hereinafter, unless otherwise specified, "XPS spectrum" is an XPS spectrum from which the background has been removed by the Shirley method. “Si2p spectrum” refers to the XPS spectrum of the 2p orbital of Si (silicon). "Baseline" refers to an extrapolated XPS spectral line (or XPS spectral curve) in the XPS spectrum assuming no photoelectron emission originating from the 2p orbital of silicon. That is, the baseline is the XPS spectral line (or XPS spectral curve) assuming no photoelectron emission originating from the 2p orbital of silicon. A "peak" in an XPS spectrum refers to a portion from when the curve departs from the low-energy side baseline to when it returns to the same baseline again. "Peak area" in an XPS spectrum refers to the area of the region between the curve that constitutes the peak and the baseline.

Hereinafter, compounds and derivatives thereof may be collectively referred to by adding "system" to the name of the compound. When the polymer name is expressed by adding "system" after the compound name, it means that the repeating unit of the polymer is derived from the compound or its derivative. Acryl and methacryl may be collectively referred to as "(meth)acryl".

The drawings referred to in the following description mainly show each component schematically for the sake of easy understanding. It may be different from the actual from above. Also, for convenience of description, in the drawings described later, the same components as those in the drawings described earlier may be denoted by the same reference numerals, and the description thereof may be omitted.

<First Embodiment: Gas Barrier Film>
A gas barrier film according to a first embodiment of the present invention has a transparent film substrate and a gas barrier layer directly or indirectly arranged on at least one main surface of the transparent film substrate. The gas barrier layer has a silicon oxynitride layer containing oxygen, nitrogen and silicon as constituent elements. The composition of silicon oxynitride contained in the silicon oxynitride layer is represented by the general formula SiO _x N _y . x and y in the general formula SiO _x N _y satisfy the relationships of 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30. In the Si2p spectrum of the silicon oxynitride layer obtained by XPS, the area of the region between the Si2p spectrum curve and the baseline in the range of binding energy 95 eV or more and 110 eV or less is defined as S1, and Si- separated from the Si2p spectrum by waveform analysis. The relationship 0.05≦S2/S1≦0.30 is satisfied, where S2 is the area of the peak derived from the Si bond.

Hereinafter, x in the general formula SiO _x N _y may be simply referred to as "x". y in the general formula SiO _x N _y may be simply described as "y". In the Si2p spectrum of the silicon oxynitride layer obtained by XPS, the area of the region between the Si2p spectrum curve and the baseline in the range of binding energy 95 eV or more and 110 eV or less is described as "area S1" or "S1". There is The area of the peak derived from the Si—Si bond separated from the Si2p spectrum by waveform analysis is sometimes referred to as “area S2” or “S2”. The methods for measuring x, y, and the area ratio (S2/S1) between S1 and S2 are the same as or similar to those used in Examples described later.

Since the gas barrier film according to the first embodiment has the above configuration, it suppresses the generation of ammonia (in particular, the generation of ammonia in a humidified environment) and has gas barrier properties even when exposed to a high-temperature and high-humidity environment. can be ensured, and it has excellent transparency. Hereinafter, the gas barrier properties after being exposed to a high temperature and high humidity environment may be referred to as "post-high temperature and high humidity gas barrier properties".

In the first embodiment, the smaller the ratio of x and y, i.e., x/y (that is, the higher the ratio of nitrogen), the higher the gas barrier properties tend to be. The higher the ratio, the less visible light is absorbed, and the transparency tends to improve.

In the first embodiment, the silicon oxynitride contained in the silicon oxynitride layer may have a stoichiometric composition or may be a non-stoichiometric composition lacking oxygen or nitrogen. Stoichiometric silicon oxynitride has x/2+3y/4=1. The value of (x/2+3y/4) is preferably 0.70 or more and 1.10 or less. Theoretically, the upper limit of (x/2+3y/4) is 1, but it may show a value greater than 1 due to excessive intake of oxygen or nitrogen. If (x/2+3y/4) is 0.70 or more, transparency and gas barrier properties tend to be enhanced.

In the first embodiment, S2/S1, which is the area ratio of S1 and S2, tends to increase as the number of Si—Si bonds in the silicon oxynitride layer increases. Further, in the first embodiment, as S2/S1 increases, gas barrier properties after high temperature and high humidity tend to increase, and the generation of ammonia (in particular, the generation of ammonia in a humidified environment) tends to be suppressed. This is because as S2/S1 increases (the number of Si—Si bonds in the silicon oxynitride layer increases), hydrolytic cleavage of Si—O bonds in the silicon oxynitride layer is suppressed, and as a result, It is presumed that this is because deterioration of the silicon oxynitride layer due to humidification is suppressed.

In the first embodiment, in order to obtain a gas barrier film with more excellent transparency, x is preferably 0.33 or more, more preferably 0.35 or more, and preferably 0.38 or more. More preferred. In the first embodiment, x is preferably 1.18 or less, more preferably 1.15 or less, and 1.12 or less in order to obtain a gas barrier film having excellent gas barrier properties after high temperature and high humidity. is more preferable.

In the first embodiment, in order to obtain a gas barrier film having excellent gas barrier properties after high temperature and high humidity, y is preferably 0.43 or more, more preferably 0.45 or more, and 0.48 or more. is more preferable. In the first embodiment, y is preferably 0.78 or less, more preferably 0.77 or less, in order to obtain a gas barrier film having excellent transparency while further suppressing the generation of ammonia. , 0.76 or less.

In the first embodiment, x/y is preferably 0.52 or more, more preferably 0.53 or more, in order to obtain a gas barrier film having excellent transparency while further suppressing the generation of ammonia. More preferably, it is still more preferably 0.54 or more. In the first embodiment, x/y is preferably 2.25 or less, more preferably 2.20 or less, in order to obtain a gas barrier film having excellent gas barrier properties after high temperature and high humidity. It is more preferably 10 or less, particularly preferably 2.00 or less, and may be 1.90 or less, 1.80 or less, or 1.70 or less.

In the first embodiment, S2/S1 is preferably 0.06 or more, more preferably 0.08 or more, in order to obtain a gas barrier film having excellent gas barrier properties after high temperature and high humidity while further suppressing the generation of ammonia. is more preferably 0.10 or more, and particularly preferably 0.15 or more. In the first embodiment, S2/S1 is preferably 0.29 or less, more preferably 0.28 or less, in order to obtain a gas barrier film with more excellent transparency. In the first embodiment, in order to obtain a gas barrier film that is more excellent in gas barrier properties and transparency after high temperature and high humidity while further suppressing the generation of ammonia, S2/S1 should be 0.06 or more and 0.30 or less. is preferably 0.08 or more and 0.30 or less, more preferably 0.10 or more and 0.30 or less, and particularly preferably 0.15 or more and 0.30 or less. It may be 15 or more and 0.29 or less, or 0.15 or more and 0.28 or less.

In the first embodiment, in order to obtain a gas barrier film that further suppresses the generation of ammonia and has further excellent gas barrier properties and transparency after high temperature and high humidity, it is preferable to satisfy the following condition 1, and the following condition 2 is satisfied. is more preferable, and it is even more preferable to satisfy the following condition 3.
Condition 1: x is 0.38 or more and 1.12 or less, and y is 0.48 or more and 0.76 or less.
Condition 2: Condition 1 above is satisfied, and x/y is 0.54 or more and 2.00 or less.
Condition 3: Condition 2 above is satisfied, and S2/S1 is 0.15 or more and 0.30 or less.

The first embodiment will be described in detail below with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of the gas barrier film according to the first embodiment. A gas barrier film 10 shown in FIG. 1 is a laminate having a transparent film substrate 11 and a gas barrier layer 12 directly disposed on one main surface 11 a of the transparent film substrate 11 . The gas barrier layer 12 has a single layer structure consisting of a silicon oxynitride layer 13 containing oxygen, nitrogen and silicon as constituent elements. The composition of the silicon oxynitride contained in the silicon oxynitride layer 13 is represented by the general formula SiO _x N _y . x and y in the general formula SiO _x N _y satisfy the relationships of 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30. In the Si2p spectrum of the silicon oxynitride layer 13 obtained by XPS, the area of the region between the Si2p spectrum curve and the baseline in the range of 95 eV or more and 110 eV or less of binding energy is defined as S1, and Si separated from the Si2p spectrum by waveform analysis The relationship 0.05≦S2/S1≦0.30 is satisfied, where S2 is the area of the peak derived from the −Si bond.

FIG. 2 is a diagram showing an example of the result of XPS analysis of the silicon oxynitride layer 13 (that is, XPS spectrum). The XPS spectrum in FIG. 2 has the background removed by the Shirley method. In FIG. 2, the vertical axis indicates intensity (counts per second, abbreviated as c/s in FIG. 2), and the horizontal axis indicates binding energy. In addition, in FIG. 2, the Si2p spectrum curve SP is drawn with a solid line, the curve P1 forming the peak derived from the Si—Si bond is drawn with a broken line, and the baseline BL is drawn with a dashed line. The peak derived from the Si—Si bond is a peak separated from the Si2p spectrum by waveform analysis. As a method of separating from the Si2p spectrum by waveform analysis, for example, there is a method of processing with a composite function (Gauss-Lorentz function) of a Gaussian function and a Lorentzian function. Specifically, using waveform analysis software (for example, “PHI MultiPak” manufactured by ULVAC-PHI), the Si2p spectrum is processed with a Gauss-Lorentz function, and a peak derived from a Si—Si bond (bond A peak having a maximum in the energy range of 99 eV or more and 101 eV or less) can be separated. In FIG. 2, the area S1 is the area between the Si2p spectrum curve SP and the baseline BL in the range of binding energy 95 eV or more and 110 eV or less. In FIG. 2, the area S2 is the area of the region between the curve P1 and the baseline BL, which constitutes the peak derived from the separated Si—Si bond. Although not shown, the XPS spectrum in FIG. 2 also includes peaks derived from Si—O bonds and Si—N bonds.

The configuration of the gas barrier film according to the first embodiment is not limited to the configuration of the gas barrier film 10 shown in FIG. For example, the gas barrier film according to the first embodiment may have a laminated structure in which the gas barrier layer is composed of a plurality of thin films, like the gas barrier film 20 shown in FIG. In the gas barrier film 20, the gas barrier layer 21 has the silicon oxynitride layer 13 and the low refractive index layer 22 disposed on the main surface 13a of the silicon oxynitride layer 13 opposite to the transparent film substrate 11 side. The low refractive index layer 22 is a layer having a lower refractive index than the silicon oxynitride layer 13 . The low refractive index layer 22 enhances gas barrier properties together with the silicon oxynitride layer 13, functions as an optical interference layer, and has the effect of reducing light reflection by the gas barrier layer 21 and increasing light transmittance. The gas barrier film according to the first embodiment may have low refractive index layers on both main surfaces of the silicon oxynitride layer.

Further, in the gas barrier film according to the first embodiment, the gas barrier layer may include two or more silicon oxynitride layers, for example, two silicon oxynitride layers and three low refractive index layers. Alternating laminates may also be used. The gas barrier layer may have a laminate structure of four layers or a laminate structure of six or more layers. For example, the gas barrier layer having a four-layer structure may be an alternate laminate in which silicon oxynitride layer/low refractive index layer/silicon oxynitride layer/low refractive index layer are arranged in this order from the transparent film substrate side. Even in an alternate laminate having an even number of layers in total, the outermost layer is preferably a low refractive index layer. The gas barrier layer, which consists of a total of four or more layers, is interposed between the silicon oxynitride layer and the low refractive index layer. A refractive index layer may be included. The gas barrier layer may be an alternately laminated body composed of a total of seven layers, that is, three silicon oxynitride layers and four low refractive index layers, or may be an alternately laminated body composed of eight or more layers.

Further, in the gas barrier film according to the first embodiment, the gas barrier layer may be indirectly arranged on the main surface of the transparent film substrate. For example, the gas barrier film 30 shown in FIG. 4 has a hard coat layer 31 arranged between the transparent film substrate 11 and the gas barrier layer 12 (silicon oxynitride layer 13). In the gas barrier film 30 , the gas barrier layer 12 is indirectly arranged on the main surface of the transparent film substrate 11 . The hard coat layer 31 is a layer that enhances mechanical properties such as hardness and elastic modulus of the gas barrier film 30 . If the main surface of the hard coat layer 31 on the side of the gas barrier layer 12 is smooth, the gas barrier property of the gas barrier layer 12 formed thereon is enhanced, and the water vapor transmission rate tends to decrease. The arithmetic mean height Sa of the main surface of the hard coat layer 31 on the side of the gas barrier layer 12 may be 1.5 nm or less or 1.0 nm or less. The arithmetic mean height Sa is calculated according to ISO 25178 from the three-dimensional surface profile of 1 μm×1 μm measured by an atomic force microscope (AFM).

The hard coat layer 31 may contain particles having a number average primary particle diameter of less than 1.0 μm (hereinafter sometimes referred to as “nanoparticles”). For example, when the hard coat layer 31 contains nanoparticles, fine irregularities are formed on the surface of the hard coat layer 31, and the adhesion between the hard coat layer 31 and the gas barrier layer 12 tends to improve.

In addition, the gas barrier film according to the first embodiment may be provided with gas barrier layers on both main surfaces of the transparent film substrate in order to further improve gas barrier properties. For example, the gas barrier film 40 shown in FIG. and a gas barrier layer 41 disposed on the . In the gas barrier film according to the first embodiment, a gas barrier layer having a laminated structure may be provided on each of both main surfaces of the transparent film substrate.

The configuration of the gas barrier layer 41 may be the same as or different from that of the gas barrier layer 12 . That is, the gas barrier layer 41 may or may not have a silicon oxynitride layer in which x, y, x/y and S2/S1 are within the above specific ranges. In order to obtain a gas barrier film having excellent transparency while further improving the gas barrier property, the gas barrier layer 41 has a silicon oxynitride layer, and the silicon oxynitride layer of the gas barrier layer 41 satisfies 0.30<x<1. .20, 0.40<y<0.80, 0.50<x/y<2.30, and 0.05≦S2/S1≦0.30.

Moreover, the gas barrier film according to the first embodiment may further have an adhesive layer. For example, a gas barrier film 50 shown in FIG. 6 has an adhesive layer 51 in addition to the structure of the gas barrier film 40 . In the gas barrier film 50, an adhesive layer 51 is arranged on the main surface 13a of the gas barrier layer 12 (silicon oxynitride layer 13) on the side opposite to the transparent film substrate 11 side.

A release liner (not shown) may be temporarily adhered to the main surface of the pressure-sensitive adhesive layer 51 opposite to the silicon oxynitride layer 13 side. The release liner protects the surface of the pressure-sensitive adhesive layer 51, for example, until the gas barrier film 50 is attached to the polarizing plate 101 (see FIG. 7), which will be described later. Plastic films made of acrylic, polyolefin, cyclic polyolefin, polyester or the like are preferably used as the constituent material of the release liner. The thickness of the release liner is, for example, 5 μm or more and 200 μm or less. The surface of the release liner is preferably subjected to release treatment. Examples of release agent materials used in release treatment include silicone-based materials, fluorine-based materials, long-chain alkyl-based materials, fatty acid amide-based materials, and the like.

The configuration of the gas barrier film according to the first embodiment has been described above with reference to the drawings. Next, elements of the gas barrier film according to the first embodiment will be described.

[Transparent film substrate 11]
The transparent film substrate 11 is a layer that serves as a base for forming the gas barrier layer. The transparent film substrate 11 may have flexibility. By using a flexible film as the base material, the gas barrier layer can be formed by a roll-to-roll method, so the productivity of the gas barrier layer can be improved. A gas barrier film in which a gas barrier layer is provided on a flexible film also has the advantage of being applicable to flexible devices and foldable devices.

The visible light transmittance of the transparent film substrate 11 is preferably 80% or higher, more preferably 90% or higher. The thickness of the transparent film substrate 11 is not particularly limited, but from the viewpoint of strength, handleability, etc., it is preferably 5 μm or more and 200 μm or less, more preferably 10 μm or more and 150 μm or less, and 30 μm or more and 100 μm or less. is more preferred.

As the resin material forming the transparent film substrate 11, a resin material excellent in transparency, mechanical strength and thermal stability is preferable. Specific examples of resin materials include cellulose resins such as triacetyl cellulose, polyester resins, polyethersulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth) Examples include acrylic resins, cyclic polyolefin resins (more specifically, norbornene resins, etc.), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures thereof.

Corona treatment, plasma treatment, flame treatment, ozone treatment, glow treatment, saponification treatment, and coupling agent are applied to the main surface of the transparent film substrate 11 on which the gas barrier layer is formed, for the purpose of improving adhesion with the gas barrier layer. Surface modification treatment such as treatment with may be applied.

The surface layer of the transparent film substrate 11 on which the gas barrier layer is formed may be a primer layer (not shown). When the surface layer on which the gas barrier layer is formed is the primer layer, the adhesion between the transparent film substrate 11 and the gas barrier layer tends to be high. Examples of materials constituting the primer layer include metals (or semi-metals) such as silicon, nickel, chromium, tin, gold, silver, platinum, zinc, indium, titanium, tungsten, aluminum, zirconium, and palladium; alloys (or metalloids); oxides, fluorides, sulfides or nitrides of these metals (or metalloids); The thickness of the primer layer is, for example, 1 nm or more and 20 nm or less, preferably 1 nm or more and 15 nm or less, and more preferably 1 nm or more and 10 nm or less.

[Silicon oxynitride layer 13]
The silicon oxynitride layer 13 is a layer mainly having a gas barrier function in the gas barrier layer, and is a layer made of a material containing silicon, oxygen and nitrogen as main constituent elements. The silicon oxynitride layer 13 may contain a small amount of elements such as hydrogen, carbon, etc. taken in from the raw material at the time of film formation, the transparent film substrate 11 and the external environment.

In the silicon oxynitride layer 13, the content of elements other than silicon, oxygen, and nitrogen is preferably 5 atomic % or less, more preferably 3 atomic % or less, and 1 atomic % or less. is more preferred. Among the elements constituting the silicon oxynitride layer 13, the total of silicon, oxygen and nitrogen is preferably 90 atomic % or more, more preferably 95 atomic % or more, and preferably 97 atomic % or more. More preferably, it may be 99 atomic % or more, 99.5 atomic % or more, or 99.9 atomic % or more.

The refractive index of the silicon oxynitride layer 13 is generally 1.50 or more and 2.20 or less, preferably 1.55 or more and 2.00 or less, and may be 1.60 or more and 1.90 or less. It may be 1.85 or less, 1.80 or less, 1.75 or less, or 1.70 or less. The silicon oxynitride layer 13 having a refractive index within this range can achieve both excellent gas barrier properties and transparency. Further, when the refractive index is 2.00 or less, there is a tendency for the light transmittance to be improved. The silicon oxynitride layer 13 tends to have a higher refractive index as the nitrogen ratio increases.

The density of the silicon oxynitride layer 13 is preferably 2.10 g/cm ³ or more. The higher the density of the silicon oxynitride layer 13, the higher the gas barrier properties tend to be. The silicon oxynitride layer 13 tends to have a higher density as the nitrogen ratio increases.

In order to obtain a gas barrier film with better gas barrier properties, the thickness of the silicon oxynitride layer 13 is preferably 5 nm or more, more preferably 10 nm or more. In order to obtain a gas barrier film with superior transparency, the thickness of the silicon oxynitride layer 13 is preferably 200 nm or less, more preferably 150 nm or less, and even more preferably 100 nm or less. In order to obtain a gas barrier film with more excellent gas barrier properties and transparency, the thickness of the silicon oxynitride layer 13 is preferably 5 nm or more and 200 nm or less, more preferably 10 nm or more and 200 nm or less, and 10 nm or more and 100 nm or less. It is even more preferable to have

A method for forming the silicon oxynitride layer 13 is not particularly limited, and may be a dry coating method or a wet coating method. A dry process such as a sputtering method, an ion plating method, a vacuum deposition method, or a chemical vapor deposition method (CVD method) is preferable because a film having a high film density and a high gas barrier property can be easily formed. A CVD method is preferable, and a plasma CVD method is more preferable, because a film having small film stress and excellent bending resistance can be easily formed.

When a flexible film is used as the transparent film substrate 11 and a gas barrier layer (for example, the silicon oxynitride layer 13) is formed (film-formed) on the flexible film, CVD film formation is performed by a roll-to-roll method. productivity can be improved. In a roll-to-roll type CVD film forming apparatus, a film forming roll constitutes one or both electrodes of a pair of opposed electrodes, and a thin film is formed on the film when the film runs on the film forming roll. be. When two film-forming rolls constitute a pair of opposing electrodes, a thin film is formed on each of the film-forming rolls, so the film-forming speed can be doubled. In addition, the expression "above" when explaining the film forming method by the CVD method has no relation to the direction in the CVD film forming apparatus, and has the same meaning as "in contact with".

Examples of the silicon source (silicon source) for forming the silicon oxynitride layer 13 by the CVD method include silicon hydride (more specifically, silane, disilane, etc.) and silicon halide (more specifically, hexamethyldisilazane, hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, tetramethylsilane, vinyltrimethoxysilane, vinyltrimethylsilane, dimethyl Silicon such as dimethoxysilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, tetraethoxysilane, diethyldiethoxysilane, methyldimethoxysilane, methyldiethoxysiloxane, monosilylamine, disilylamine, trisilylamine, etc. compound. Among these, trisilylamine is preferable because it has low toxicity, a low boiling point, and can form a highly transparent and high-density film. Also, when trisilylamine is used as the silicon source, the number of Si—Si bonds in the silicon oxynitride layer 13 tends to increase. Therefore, the use of trisilylamine as the silicon source facilitates the adjustment of S2/S1.

In order to form the silicon oxynitride layer 13, normally, in addition to the silicon source, a nitrogen source gas and an oxygen source gas are introduced. Nitrogen sources include nitrogen and ammonia. Oxygen sources include oxygen, carbon monoxide, carbon dioxide, and the like. Nitrogen (nitrogen gas) is preferable as the nitrogen source, and oxygen (oxygen gas) is preferable as the oxygen source, from the viewpoint of reducing hydrogen and carbon taken into the film.

In general, a silicon nitride film formed by a CVD method by introducing a nitrogen source together with trisilylamine as a silicon source has a _large amount of hydrogen in the film, and a wave number of 2140 cm ^{− 1} (range of 2120 cm ⁻¹ to 2150 cm ⁻¹ ). In addition, in general, a silicon oxynitride film formed by a CVD method by introducing nitrogen and oxygen together with trisilylamine as a silicon source shifts the infrared absorption peak to the high wave number side, and is 2160 cm ⁻¹ to 2280 cm It exhibits an infrared absorption peak in the range of ^-1 or less, and exhibits transparency superior to that of silicon nitride films. Oxygen has a strong bonding force with silicon, so it is presumed that the introduction of oxygen suppresses the uptake of hydrogen into the film, which is one of the reasons for the improvement in transparency.

By changing the introduction amount of at least one of the nitrogen source and the oxygen source with respect to the silicon source, the composition of the silicon oxynitride layer 13 can be appropriately adjusted. When nitrogen is used as the nitrogen source and oxygen is used as the oxygen source, from the viewpoint of achieving both transparency and gas barrier properties, the amount of oxygen to be introduced is set to 0.05 by volume with respect to the amount of nitrogen to be introduced. It is preferably 0.1 times or more and 5 times or less, more preferably 0.03 times or more and 2 times or less, further preferably 0.04 times or more and 1.5 times or less, and 0.04 times or more and 1 0 times or less, or 0.04 times or more and 0.5 times or less. If the amount of oxygen introduced is excessively small, the amount of oxygen introduced into the film tends to be small and the light transmittance of the film tends to decrease. If the amount of oxygen introduced is excessively large, the amount of nitrogen incorporated into the film tends to be small, resulting in insufficient gas barrier properties.

S2/S1 can be adjusted, for example, by changing at least one of the introduction amount of the nitrogen source (preferably nitrogen) relative to the silicon source and the type of silicon source. In order to easily adjust S2/S1, the silicon source is preferably a silicon compound having two or more silicon atoms in one molecule and having a Si—N bond, more preferably trisilylamine. .

Gases other than the silicon source, the nitrogen source, and the oxygen source may be used as the introduction gas for film formation by the CVD method. For example, when using a liquid such as trisilylamine, a carrier gas may be used to vaporize the liquid and introduce it into the chamber (vacuum chamber). Also, a nitrogen source or an oxygen source may be mixed with a carrier gas and introduced into the vacuum chamber, or a discharge gas may be used to stabilize the plasma discharge. Carrier gas and discharge gas include rare gases such as helium, argon, neon, and xenon, and hydrogen. A rare gas is preferable from the viewpoint of reducing the amount of hydrogen taken into the film and increasing the transparency.

Various conditions in the plasma CVD method may be appropriately set. The substrate temperature (temperature of the surface of the film-forming roll) is set, for example, within the range of -20°C or higher and 500°C or lower. The substrate temperature (film substrate temperature) when forming a gas barrier layer (for example, silicon oxynitride layer 13) on a film substrate is preferably 150° C. or less from the viewpoint of the heat resistance of the film substrate. The temperature is preferably 100° C. or lower, and more preferably 100° C. or lower. The pressure in the film forming chamber (inside the vacuum chamber) is, for example, 0.001 Pa or more and 50 Pa or less. An AC power supply, for example, is used as the power supply for plasma generation. The frequency of the power supply in roll-to-roll CVD film formation is generally in the range of 50 Hz to 500 kHz. The applied power in roll-to-roll CVD film formation is generally 0.1 kW or more and 10 kW or less.

The density of the silicon oxynitride layer 13 formed by the CVD method is, for example, 2.10 g/cm ³ or more and 2.50 g/cm ³ or less, and 2.15 g/cm ³ or more and 2.45 g/cm ³ or less. It may be 20 g/cm ³ or more and 2.40 g/cm ³ or less, or 2.25 g/cm ³ or more and 2.35 g/cm ³ or less.

[Low refractive index layer 22]
The material of the low refractive index layer 22 is not particularly limited as long as it has a lower refractive index than the silicon oxynitride layer 13, and may be an organic layer or an inorganic layer. Examples of the inorganic material forming the low refractive index layer 22 include silicon oxide and magnesium fluoride. The refractive index difference between the silicon oxynitride layer 13 and the low refractive index layer 22 is preferably 0.10 or more, and may be 0.13 or more or 0.15 or more. The refractive index difference is generally 1.0 or less, and may be 0.5 or less, 0.4 or less, or 0.3 or less. The refractive index of the low refractive index layer 22 may be 1.30 or more and 1.55 or less, or 1.40 or more and 1.52 or less.

Low refractive index layer 22 is preferably a silicon oxide layer. The silicon oxide layer may contain a small amount of elements such as hydrogen, carbon, nitrogen, etc. taken in from raw materials during film formation, the transparent film substrate 11 and the external environment. If the silicon oxide layer contains nitrogen, the nitrogen content is preferably lower than that of the silicon oxynitride layer 13 . In the silicon oxide layer, the content of elements other than silicon and oxygen is preferably 5 atomic % or less.

A method for forming the low refractive index layer 22 is not particularly limited, and may be a dry coating method or a wet coating method. When the silicon oxynitride layer 13 is formed by the CVD method, the low refractive index layer 22 is also preferably formed by the CVD method from the viewpoint of productivity.

As the silicon source and oxygen source for forming the silicon oxide layer (more specifically, the silicon oxide layer as the low refractive index layer 22) by the CVD method, those exemplified above regarding the formation of the silicon oxynitride layer 13 are used. mentioned. As the silicon source, organosilicon compounds are preferable because they have low toxicity and can suppress the incorporation of nitrogen into the film. They can suppress the incorporation of impurities into the film, and can form films with high transparency and gas barrier properties. Hexamethyldisiloxane is more preferable because When an organosilicon compound such as hexamethyldisiloxane is used as the silicon source, carbon may be incorporated into the film. good. From the viewpoint of reducing the amount of carbon in the film, oxygen gas is preferable as the oxygen source.

As the amount of oxygen source introduced relative to the silicon source increases, the amount of carbon in the film tends to decrease and the film density tends to increase. When forming a silicon oxide layer by a CVD method using hexamethyldisiloxane and oxygen, the amount of oxygen introduced is preferably at least 10 times the amount of hexamethyldisiloxane (gas) introduced in volume ratio. It may be 15 times or more or 20 times or more. From the viewpoint of appropriately maintaining the film formation rate, the amount of oxygen introduced is preferably 200 times or less, and preferably 100 times or less or 50 times or less, the volume ratio of the amount of hexamethyldisiloxane (gas) introduced. good too.

A carrier gas or a discharge gas may be introduced in the CVD film formation of the silicon oxide layer. Various conditions such as substrate temperature, pressure, power supply frequency, and applied power may be appropriately adjusted in the same manner as in the deposition of the silicon oxynitride layer 13 .

From the viewpoint of making the silicon oxide layer as the low refractive index layer 22 contribute to improving gas barrier properties, the density of the silicon oxide layer is preferably 1.80 g/cm ³ or more, and more preferably 1.90 g/cm ³ or more. is more preferably 2.00 g/cm ³ or more and 2.40 g/cm ³ or less, 2.05 g/cm ³ or more and 2.35 g/cm ³ or less, or 2.10 g/cm ³ or more and 2.30 g/cm ³ or less There may be.

From the viewpoint of allowing the low refractive index layer 22 to function properly as an optical interference layer, the thickness of the low refractive index layer 22 is preferably 3 nm or more and 250 nm or less, and may be 5 nm or more and 200 nm or less, or 10 nm or more and 150 nm or less. . It is preferable to set the thickness of the low refractive index layer 22 so that the light reflectance of the gas barrier layer is small and the coloring of the reflected light is suppressed. The properties (spectrum) of reflected light can be accurately evaluated by optical model calculations. As a method of obtaining the reflection spectrum of a multi-layer optical thin film by optical calculation, the method of repeatedly applying the thin film interference formula to each interface of the thin film and summing all the multiple reflected waves, and the boundary conditions of Maxwell's equations There is known a method of calculating a reflection spectrum by a transfer matrix in consideration of .

The gas barrier layer may include layers (other layers) other than the silicon oxynitride layer 13 and the low refractive index layer 22 . Examples of "other layers" include inorganic thin films made of ceramic materials such as metal or semi-metal oxides, nitrides or oxynitrides. Oxides, nitrides or oxynitrides of Si, Al, In, Sn, Zn, Ti, Nb, Ce or Zr are preferred because they have both low moisture permeability and transparency.

From the viewpoint of achieving both high gas barrier properties and transparency, the total thickness of the gas barrier layer is preferably 30 nm or more and 1000 nm or less, more preferably 40 nm or more and 500 nm or less.

[Hard coat layer 31]
The hard coat layer 31 contains, for example, a binder resin and nanoparticles. As the binder resin, curable resins such as thermosetting resins, photocurable resins and electron beam curable resins are preferably used. Types of curable resins include polyester resins, acrylic resins, urethane resins, acrylic urethane resins, amide resins, silicone resins, silicate resins, epoxy resins, melamine resins, oxetane resins, and acrylic resins. Urethane-based resins and the like are included. One or more curable resins can be used. Among these, one or more selected from the group consisting of acrylic resins, acrylic urethane resins, and epoxy resins are preferable because they have high hardness and can be photocured, and acrylic resins and acrylic urethane resins. More preferably, one or more selected from the group consisting of

The number average primary particle diameter of the nanoparticles contained in the hard coat layer 31 is preferably 15 nm or more, more preferably 20 nm or more, from the viewpoint of enhancing dispersibility in the binder resin. From the viewpoint of forming fine irregularities that contribute to improved adhesion, the number average primary particle diameter of the nanoparticles contained in the hard coat layer 31 is preferably 90 nm or less, more preferably 70 nm or less. It is more preferably 50 nm or less.

Inorganic oxides are preferred as the material for the nanoparticles. Examples of inorganic oxides include metal (or metalloid) oxides such as silica, titanium oxide, aluminum oxide, zirconium oxide, niobium oxide, zinc oxide, tin oxide, cerium oxide, and magnesium oxide. The inorganic oxide may be a composite oxide of multiple (semi)metals. Among the exemplified inorganic oxides, silica is preferable because it has a high adhesion improving effect. That is, silica particles (nanosilica particles) are preferable as the nanoparticles. A functional group such as an acrylic group or an epoxy group may be introduced into the surface of the inorganic oxide particles as nanoparticles for the purpose of enhancing adhesion and affinity with the resin.

The amount of the nanoparticles in the hard coat layer 31 is preferably 5 parts by weight or more, 10 parts by weight or more, 20 parts by weight or more, or 30 parts by weight or more with respect to 100 parts by weight of the total amount of the binder resin and the nanoparticles. may be If the amount of the nanoparticles is 5 parts by weight or more, the adhesion to the gas barrier layer formed on the hard coat layer 31 can be improved. The upper limit of the amount of nanoparticles in the hard coat layer 31 is, for example, 90 parts by weight, preferably 80 parts by weight, and preferably 70 parts by weight with respect to 100 parts by weight of the total amount of the binder resin and the nanoparticles. good too.

The thickness of the hard coat layer 31 is not particularly limited, but is preferably 0.5 μm or more, more preferably 1.0 μm or more, in order to improve the adhesion to the gas barrier layer while achieving high hardness. It is more preferably 2.0 μm or more, and even more preferably 3.0 μm or more. On the other hand, the thickness of the hard coat layer 31 is preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 12 μm or less, in order to suppress a decrease in strength due to cohesive failure.

(Method for Forming Hard Coat Layer 31)
The hard coat layer 31 is formed by applying the hard coat composition onto the transparent film substrate 11, and optionally removing the solvent and curing the resin. The hard coat composition contains, for example, the above binder resin and nanoparticles, and optionally contains a solvent capable of dissolving or dispersing these components. When the resin component in the hard coat composition is a curable resin, the hard coat composition preferably contains an appropriate polymerization initiator. For example, when the resin component in the hard coat composition is a photocurable resin, the hard coat composition preferably contains a photopolymerization initiator.

In addition to the above components, the hard coat composition includes particles (microparticles) having a number average primary particle diameter of 1.0 μm or more, leveling agents, viscosity modifiers (thixotropic agents, thickeners, etc.), antistatic agents, blocking agents, Additives such as inhibitors, dispersants, dispersion stabilizers, antioxidants, UV absorbers, antifoaming agents, surfactants and lubricants may be included.

As a method for applying the hard coat composition, any suitable method such as bar coating, roll coating, gravure coating, rod coating, slot orifice coating, curtain coating, fountain coating, comma coating, etc. can be used. can be adopted.

[Adhesive layer 51]
As a constituent material of the adhesive layer 51, an adhesive having a high visible light transmittance is preferably used. Examples of adhesives constituting the adhesive layer 51 include acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyvinyl ethers, vinyl acetate-vinyl chloride copolymers, modified polyolefins, epoxy resins, and fluorine resins. , natural rubber, synthetic rubber or the like as a base polymer can be appropriately selected and used. The thickness of the adhesive layer 51 is, for example, 5 μm or more and 100 μm or less. The refractive index of the adhesive layer 51 is, for example, 1.4 or more and 1.5 or less.

[Characteristics of gas barrier film]
The water vapor transmission rate of the gas barrier film is preferably 3.0×10 ⁻² g/m ² ·day or less, more preferably 2.0×10 ⁻² g/m ² ·day or less. It is more preferably 0×10 ⁻² g/m ² ·day or less. From the viewpoint of suppressing deterioration of the protection object such as the organic EL element, the lower the water vapor transmission rate, the better. Although the lower limit of the water vapor transmission rate of the gas barrier film is not particularly limited, it is generally 1.0×10 ⁻⁵ g/m ² ·day. Water vapor transmission rate (WVTR) is measured according to the differential pressure method (Pressure Sensor Method) described in ISO 15106-5 under conditions of a temperature of 40° C. and a relative humidity of 90%.

The light transmittance of the gas barrier film is preferably 75% or more, more preferably 80% or more. Light transmittance is the Y value of the CIE tristimulus values specified in JlS Z8781-3:2016.

The amount of ammonium ions extracted from 1 cm ² of the gas barrier film is preferably 0.30 μg or less. The method for measuring the extracted amount of ammonium ions is the same method as in Examples described later or a method based thereon.

<Second Embodiment: Method for Producing Gas Barrier Film>
Next, a method for manufacturing a gas barrier film according to the second embodiment of the present invention will be described. The method for manufacturing the gas barrier film according to the second embodiment is a suitable method for manufacturing the gas barrier film according to the first embodiment described above. Therefore, descriptions of components that overlap with those of the above-described first embodiment may be omitted. In the method for producing a gas barrier film according to the second embodiment, trisilylamine, a nitrogen source (eg, nitrogen), and an oxygen source (eg, oxygen) are introduced into a chamber (vacuum chamber) of a film forming apparatus. and forming a silicon oxynitride layer by a CVD method.

In the second embodiment, for example, by using a CVD film forming apparatus (not shown) and adopting the conditions of the plasma CVD method illustrated in the explanation of the gas barrier film according to the first embodiment, Such a gas barrier film can be easily produced. For example, when producing the gas barrier film according to the first embodiment using a CVD film forming apparatus (not shown) in which a pair of film forming rolls constitutes a pair of counter electrodes, a film forming gas (more specifically trisilylamine, an oxygen source, a nitrogen source, etc.) is supplied into the vacuum chamber, and plasma discharge is generated between a pair of film-forming rolls, so that the film-forming gas is decomposed by the plasma. A silicon oxynitride layer 13 is formed on the film substrate 11 . Each value of x, y and x/y can be adjusted, for example, by changing the introduction amount of at least one of the nitrogen source and the oxygen source to trisilylamine. Also, S2/S1 can be adjusted, for example, by changing the introduction amount of a nitrogen source (preferably nitrogen) to trisilylamine.

<Third Embodiment: Polarizing Plate with Gas Barrier Layer>
Next, a polarizing plate with a gas barrier layer according to a third embodiment of the present invention will be described. A polarizing plate with a gas barrier layer according to the third embodiment includes the gas barrier film according to the first embodiment and a polarizer. FIG. 7 is a cross-sectional view showing an example of a polarizing plate with a gas barrier layer according to the third embodiment. A polarizing plate 100 with a gas barrier layer shown in FIG. 7 has the above-described gas barrier film 50 and a polarizing plate 101 . In the polarizing plate 100 with a gas barrier layer, the polarizing plate 101 is arranged on the main surface 51a of the pressure-sensitive adhesive layer 51 opposite to the silicon oxynitride layer 13 side. That is, the polarizing plate 101 and the silicon oxynitride layer 13 are bonded together with the adhesive layer 51 interposed therebetween. Although the polarizing plate 100 with a gas barrier layer shown in FIG. 7 has a gas barrier film 50 (gas barrier film 40), the gas barrier film of the polarizing plate with a gas barrier layer according to the third embodiment is not limited to the gas barrier film 50. For example, it may be the gas barrier film 10, the gas barrier film 20, or the gas barrier film 30.

The polarizing plate 101 includes a polarizer (not shown), and generally transparent protective films (not shown) are laminated as polarizer protective films on both main surfaces of the polarizer. A transparent protective film may not be provided on one principal surface or both principal surfaces of the polarizer. As a polarizer, for example, a hydrophilic polymer film such as a polyvinyl alcohol film is uniaxially stretched after adsorbing a dichroic substance such as iodine or a dichroic dye.

As the transparent protective film, a transparent resin film composed of a cellulose-based resin, a cyclic polyolefin-based resin, an acrylic-based resin, a phenylmaleimide-based resin, a polycarbonate-based resin, or the like is preferably used. A gas barrier film may be used as the transparent protective film.

The polarizing plate 101 may include an optical functional film laminated on one or both main surfaces of a polarizer via an appropriate adhesive layer or adhesive layer as necessary. Examples of the optical functional film include retardation plates, viewing angle widening films, viewing angle limiting (peep prevention) films, brightness improving films, and the like.

Since the polarizing plate with a gas barrier layer according to the third embodiment includes the gas barrier film according to the first embodiment, it is possible to suppress the generation of ammonia and ensure gas barrier properties even when exposed to a high-temperature and high-humidity environment. , excellent transparency.

<Fourth Embodiment: Image Display Device>
Next, an image display device according to a fourth embodiment of the invention will be described. An image display device according to the fourth embodiment includes the gas barrier film according to the first embodiment or the polarizing plate with a gas barrier layer according to the third embodiment, and an image display cell.

FIG. 8 is a cross-sectional view showing an example of an image display device according to the fourth embodiment. An image display device 200 shown in FIG. 8 includes a gas barrier layer-attached polarizing plate 100 having a gas barrier film 50 and an image display cell 202 . The image display cell 202 includes a substrate 203 and display elements 204 provided on the substrate 203 . In the image display device 200 , the gas barrier layer 41 and the display element 204 are bonded together with the adhesive layer 201 interposed therebetween. Although the image display device 200 shown in FIG. 8 has the gas barrier film 50 (gas barrier film 40), the gas barrier film of the image display device according to the fourth embodiment is not limited to the gas barrier film 50. For example, the gas barrier film 10, it may be the gas barrier film 20 or the gas barrier film 30;

As the adhesive constituting the adhesive layer 201, for example, the same adhesive as those exemplified as the adhesive constituting the adhesive layer 51 described above can be used. The adhesive that forms the adhesive layer 201 and the adhesive that forms the adhesive layer 51 may be of the same type or of different types.

A preferable range of the thickness of the adhesive layer 201 is, for example, the same as the preferable range of the thickness of the adhesive layer 51 described above. The thickness of the adhesive layer 201 and the thickness of the adhesive layer 51 may be the same or different.

A glass substrate or a plastic substrate is used as the substrate 203 . When the image display cell 202 is of the top emission type, the substrate 203 does not have to be transparent, and a highly heat-resistant film such as a polyimide film may be used as the substrate 203 .

Examples of the display element 204 include an organic EL element, a liquid crystal element, an electrophoretic display element (electronic paper), and the like. A touch panel sensor (not shown) may be arranged on the viewing side of the image display cell 202 .

When the display element 204 is an organic EL element, the image display cell 202 is, for example, a top emission type. The organic EL element includes, for example, a metal electrode (not shown), an organic light emitting layer (not shown), and a transparent electrode (not shown) in this order from the substrate 203 side.

The organic light emitting layer may include an electron transport layer, a hole transport layer, etc., in addition to the organic layer that itself functions as a light emitting layer. The transparent electrode is a metal oxide layer or a metal thin film and transmits light from the organic light emitting layer. A back sheet (not shown) may be provided on the back side of the substrate 203 for the purpose of protecting and reinforcing the substrate 203 .

The metal electrodes of the organic EL element are light reflective. Therefore, when external light enters the inside of the image display cell 202, the light is reflected by the metal electrodes, and the reflected light is visually recognized as a mirror surface from the outside. By arranging a circularly polarizing plate as the polarizing plate 101 on the viewing side of the image display cell 202, the re-emission of light reflected by the metal electrode to the outside is prevented, and the visibility and design of the screen of the image display device 200 are improved. can improve sexuality.

The circularly polarizing plate includes, for example, a retardation film on the main surface of the polarizer on the image display cell 202 side. The transparent protective film arranged adjacent to the polarizer may be a retardation film. Further, the transparent film substrate 11 of the gas barrier film 50 may be a retardation film. Lamination of the polarizer and the retardation film when the retardation film has a retardation of λ / 4 and the angle formed by the slow axis direction of the retardation film and the absorption axis direction of the polarizer is 45 ° The body functions as a circular polarizer for suppressing re-emission of reflected light from the metal electrode. The retardation film that constitutes the circularly polarizing plate may be a laminate of two or more layers of films. For example, by laminating a polarizer, a λ/2 plate and a λ/4 plate so that their optical axes form a predetermined angle, a broadband circularly polarizing plate that functions as a circularly polarizing plate over a wide band of visible light is obtained. can get.

The image display cell 202 may be of a bottom emission type in which a transparent electrode, an organic light emitting layer and a metal electrode are laminated in this order on a substrate. In the bottom emission type image display cell 202, a transparent substrate is used, and the transparent substrate is arranged on the viewing side. A gas barrier film may be used as the transparent substrate.

Since the image display device according to the fourth embodiment includes the gas barrier film according to the first embodiment, deterioration of the display element caused by gas (for example, water vapor) can be suppressed.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.

<Production of gas barrier film>
The methods for producing the gas barrier films of Examples 1 to 3 and Comparative Examples 1 to 7 are described below. In the preparation of the gas barrier films of Examples 1 to 3 and Comparative Examples 1 to 5 and 7, the gas barrier layer (silicon oxynitride layer or silicon oxide layer) was formed by roll-to-roll CVD. A membrane device was used. In addition, in the production of the gas barrier film of Comparative Example 6, a roll-to-roll type sputtering deposition apparatus was used for the deposition of the silicon oxynitride layer.

[Example 1]
A 40 μm-thick cyclic polyolefin film (“Zeonor (registered trademark) film ZF-14” manufactured by Nippon Zeon Co., Ltd.) as a transparent film substrate was set in a film forming apparatus, and the pressure in the vacuum chamber was reduced to 1×10 ⁻³ Pa. . Next, while the film was running, a silicon oxynitride layer (gas barrier layer) having a thickness of 60 nm was formed by CVD at a substrate temperature of 12° C. to obtain a gas barrier film of Example 1. In the CVD film formation for obtaining the gas barrier film of Example 1, the frequency of the power supply for plasma generation was set to 80 Hz, and plasma was generated by discharging under the conditions of an applied power of 1.0 kW, and trisilylamine ( TSA) (flow condition: 30 sccm), nitrogen (flow condition: 575 sccm) and oxygen (flow condition: 25 sccm) are used, and the film-forming gas is introduced between the film-forming rolls (between the electrodes) in the vacuum chamber, and the pressure is A film was formed at 1.0 Pa. Note that TSA was vaporized by heating and introduced into the vacuum chamber.

[Example 2]
A gas barrier film of Example 2 was produced in the same manner as in Example 1, except that the nitrogen flow conditions were set to 550 sccm and the oxygen flow conditions were set to 50 sccm.

[Example 3]
A gas barrier film of Example 3 was produced in the same manner as in Example 1, except that the nitrogen flow conditions were set to 525 sccm and the oxygen flow conditions were set to 75 sccm.

[Comparative Example 1]
A gas barrier film of Comparative Example 1 was produced in the same manner as in Example 1, except that the nitrogen flow rate was set to 600 sccm and oxygen was not introduced.

[Comparative Example 2]
A gas barrier film of Comparative Example 2 was produced in the same manner as in Example 1, except that the nitrogen flow conditions were set to 300 sccm and the oxygen flow conditions were set to 300 sccm.

[Comparative Example 3]
A gas barrier film of Comparative Example 3 was produced in the same manner as in Example 1, except that the oxygen flow rate was set to 600 sccm and nitrogen was not introduced.

[Comparative Example 4]
A gas barrier film of Comparative Example 4 was produced in the same manner as in Example 1, except for the following changes.

(change point)
In Comparative Example 4, hexamethyldisiloxane (HMDSO) (flow rate: 20 sccm), nitrogen (flow rate: 300 sccm), and oxygen (flow rate: 400 sccm) were used as deposition gases, and a silicon oxynitride layer having a thickness of 150 nm was formed. (gas barrier layer) was deposited by CVD. Note that HMDSO was vaporized by heating and introduced into the vacuum chamber.

[Comparative Example 5]
A gas barrier film of Comparative Example 5 was produced in the same manner as in Example 1 except for the following changes.

(change point)
In Comparative Example 5, HMDSO (flow rate: 25 sccm) and oxygen (flow rate: 700 sccm) were used as deposition gases, and a silicon oxide layer (gas barrier layer) with a thickness of 180 nm was deposited by CVD. Note that HMDSO was vaporized by heating and introduced into the vacuum chamber.

[Comparative Example 6]
A cyclic polyolefin film (“Zeonor (registered trademark) film ZF-14” manufactured by Nippon Zeon Co., Ltd.) with a thickness of 40 μm as a transparent film substrate was set in a film forming apparatus, and the pressure in the vacuum chamber was reduced to 1×10 ⁻⁴ Pa. . Next, while the film was running, the substrate temperature was set to −8° C., and a silicon oxynitride layer (gas barrier layer) with a thickness of 220 nm was formed by DC magnetron sputtering to obtain a gas barrier film of Comparative Example 6. In the sputtering film formation for obtaining the gas barrier film of Comparative Example 6, a pure Si target was used as the target, and Ar/O ₂ /N ₂ was introduced as the sputtering gas at a volume ratio of 23.5/1.0/23.5. Then, sputtering was performed under the conditions of a power density of 2.23 W/cm ² and a pressure of 0.15 Pa.

[Comparative Example 7]
A gas barrier film of Comparative Example 7 was produced in the same manner as in Example 1, except that the nitrogen flow conditions were set to 400 sccm and the oxygen flow conditions were set to 200 sccm.

<Composition analysis of gas barrier layer>
Using an X-ray photoelectron spectrometer equipped with an Ar ion gun (“Quantera SXM” manufactured by ULVAC-Phi, Inc.), the main surface of the gas barrier layer (silicon oxynitride layer or silicon oxide layer) opposite to the transparent film substrate side Composition analysis in the thickness direction of the gas barrier layer was performed by XPS while the gas barrier layer was etched under the following conditions. Then, the content of each element (Si, O, N, and C) in the central portion of the gas barrier layer in the thickness direction (when 1/2 of the total etching time has elapsed) is calculated, and the general formula showing the composition of the gas barrier layer is The values of x and y in SiO _x N _y were obtained. In addition, "total etching time" means the time from the start to the end of etching. Peaks corresponding to the binding energies of 2p of Si, 1s of O, 1s of N, and 1s of C obtained from the wide scan spectrum were used to calculate the content of each element. Detailed measurement conditions are shown below. In the gas barrier layers of Examples 1 to 3, the content of C with respect to the total 100 atomic % of Si, O, N and C was 0 atomic %.

[Measurement condition]
X-ray source: monochrome AlKα
X-ray focal size: 100 μmφ (15 kV, 25 W)
Photoelectron extraction angle: 45° with respect to the sample surface
Bond energy correction: CC bond derived peak corrected to 285.0 eV (top surface only)
Charge neutralization conditions: combined use of electron neutralization gun and Ar ion gun (neutralization mode) Acceleration voltage of Ar ion gun: 1 kV
Ar ion gun raster size: 1mm x 1mm
Etching rate of Ar ion gun: 5 nm/min (in terms of _SiO2 )

<Measurement of S2/S1 of gas barrier layer>
An XPS analysis was performed under the same conditions as <Composition analysis of the gas barrier layer> to obtain a Si2p spectrum of the central portion in the thickness direction of the gas barrier layer (when 1/2 of the total etching time has elapsed). The obtained Si2p spectrum was subjected to waveform analysis using waveform analysis software (“PHI MultiPak” manufactured by ULVAC-Phi, Inc.) to obtain S2/S1 of the gas barrier layer. Specifically, using the waveform analysis software, after removing the background of the Si2p spectrum by the Shirley method, the spectrum is processed with a Gauss-Lorentz function to obtain a peak derived from the Si—Si bond from the spectrum ( A peak having a maximum in the range of binding energy 99 eV or more and 101 eV or less) was separated. Next, using the waveform analysis software, the area S1 (the area of the region between the Si2p spectrum curve and the baseline in the range of binding energy 95 eV or more and 110 eV or less) and the area S2 (derived from the separated Si—Si bond The area of the peak to be measured) was measured, and the area ratio (S2/S1) was calculated.

<Infrared spectroscopic measurement of gas barrier layer>
Using an FT-IR device (“Frontier” manufactured by PerkinElmer), the infrared absorption spectrum of the gas barrier layer in the wave number range of 2160 cm ⁻¹ to 2280 cm ⁻¹ is measured by the reflection method (ATR method), and the absorption peak is obtained. confirmed the wavenumber of

<Method for evaluating gas barrier film>
[Light transmittance]
The light transmittance (Y value) of the gas barrier film was measured with a spectrophotometer ("U4100" manufactured by Hitachi High-Tech Science). When the light transmittance was 75% or more, it was evaluated as "excellent in transparency". On the other hand, when the light transmittance was less than 75%, it was evaluated as "not excellent in transparency".

[Water vapor transmission rate]
According to the differential pressure method (Pressure Sensor Method) described in ISO 15106-5, using a water vapor transmission rate measuring device "Deltaperm (registered trademark)" manufactured by Technolox, under the conditions of a temperature of 40 ° C. and a relative humidity of 90%, The water vapor transmission rate (WVTR) of the gas barrier film was measured. The WVTR obtained here is hereinafter referred to as "initial WVTR". The initial WVTR values of Comparative Examples 4 to 6 were normalized based on a gas barrier layer having a thickness of 60 nm. For example, the initial WVTR of Comparative Example 4 is a value calculated by multiplying the measured value obtained by the above measuring method by 150/60.

A gas barrier film (sample) prepared separately from the gas barrier film for which the initial WVTR was measured was used to measure the WVTR after being exposed to a high-temperature and high-humidity environment. Specifically, first, the sample was placed in an oven set at a temperature of 85° C. and a relative humidity of 85% for 240 hours. Next, the sample was taken out from the oven, and the WVTR of the sample after exposure to the high temperature and high humidity environment was measured by the same method as the initial WVTR measurement method. The WVTR obtained here is hereinafter referred to as "high temperature and high humidity WVTR". For the high-temperature, high-humidity WVTR of Comparative Examples 4 to 6, the values were normalized based on the gas barrier layer having a thickness of 60 nm. For example, the high-temperature, high-humidity WVTR of Comparative Example 4 is a value calculated by multiplying the measured value obtained by the above measuring method by 150/60. When the high-temperature, high-humidity WVTR was 0.10 g/m ² ·day or less, it was evaluated as "the gas barrier property can be secured even when exposed to a high-temperature, high-humidity environment". On the other hand, when the high-temperature, high-humidity WVTR exceeded 0.10 g/m ² ·day, it was evaluated as "the gas barrier property cannot be ensured after being exposed to the high-temperature, high-humidity environment".

[Extraction amount of ammonium ions]
First, the gas barrier film was cut into a size of 60 mm×60 mm to obtain a sample for measurement. Next, after putting the obtained sample into a container made of polypropylene, 100 mL of ultrapure water was put into the container. Next, the container containing the sample and ultrapure water was placed in a dryer set at a temperature of 120° C. for 1 hour, and then the liquid (extract) in the container was filtered through a membrane filter with a pore size of 0.2 μm. Then, using ion chromatography (IC method), the amount of ammonium ions (extracted amount) in the resulting filtrate was quantified under the following conditions. A commercially available ammonium ion standard solution (manufactured by Kanto Kagaku Co., Ltd.) was used for quantification. When the amount of extracted ammonium ions per 1 cm ² of the sample was 0.30 µg or less, it was evaluated as "ammonia generation can be suppressed." On the other hand, when the amount of extracted ammonium ions per 1 cm ² of the sample exceeded 0.30 µg, it was evaluated as "the generation of ammonia cannot be suppressed."

(Measurement conditions for the IC method)
Analyzer: Thermo Fisher Scientific "Dionex (registered trademark) ICS-6000"
Separation column: Thermo Fisher Scientific "Dionex (registered trademark) IonPac CS16 (3 mm × 250 mm)"
Guard column: Thermo Fisher Scientific "Dionex (registered trademark) IonPac CG16 (3 mm × 50 mm)"
Suppressor: Thermo Fisher Scientific "Dionex (registered trademark) CDRS 600 (external mode)"
Detector: Conductivity detector Eluent: Methanesulfonic acid aqueous solution (concentration of methanesulfonic acid: 25 mmol/L)
Eluent flow rate: 0.36 mL/min Injection volume of sample (filtrate): 5 μL

<Analysis results and evaluation results>
For Examples 1 to 3 and Comparative Examples 1 to 7, the value of x, the value of y and the value of x/y in SiO _x N _y , S2/S1, and the redness in the wavenumber range of 2160 cm ⁻¹ to 2280 cm ⁻¹ Table 1 shows the wave number of the absorption peak of the external absorption spectrum. Table 2 shows the light transmittance, the initial WVTR, the high-temperature and high-humidity WVTR, and the amount of extracted ammonium ions per 1 cm ² of the sample for Examples 1 to 3 and Comparative Examples 1 to 7.

The “absorption peak wavenumber” in Table 1 is the wavenumber of the absorption peak of the infrared absorption spectrum in the wavenumber range of 2160 cm ⁻¹ to 2280 cm ⁻¹ . In the column of "absorption peak wavenumber" in Table 1, "-" means that there was no absorption peak in the wavenumber range of 2160 cm ^-1 or more and 2280 cm ^-1 or less. In addition, "NH ₄ ⁺ extraction amount" in Table 2 is the extraction amount of ammonium ions per 1 cm ² of the sample. In the column of "NH ₄ ⁺ extraction amount" in Table 2, "-" means that the extraction amount of ammonium ions was not measured.

As shown in Table 1, in Examples 1 to 3, x and y are 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30. fulfilled the relationship. In Examples 1 to 3, S2/S1 was 0.05 or more and 0.30 or less.

As shown in Table 2, in Examples 1 to 3, the light transmittance was 75% or more. Therefore, the gas barrier films of Examples 1 to 3 were excellent in transparency. In Examples 1 to 3, the high-temperature, high-humidity WVTR was 0.10 g/m ² ·day or less. Therefore, the gas barrier films of Examples 1 to 3 were able to secure gas barrier properties even when exposed to a high-temperature and high-humidity environment. In Examples 1 to 3, the amount of ammonium ions extracted per 1 cm ² of the sample was 0.30 μg or less. Therefore, the gas barrier films of Examples 1 to 3 were able to suppress the generation of ammonia.

As shown in Table 1, in Comparative Example 1, x was 0.30 or less. In Comparative Examples 2 to 5 and 7, x was 1.20 or more. In Comparative Examples 2 to 5 and 7, y was 0.40 or less. In Comparative Example 1, x/y was 0.50 or less. In Comparative Examples 2 to 4 and 7, x/y was 2.30 or more. In Comparative Example 1, S2/S1 exceeded 0.30. In Comparative Examples 2 to 7, S2/S1 was less than 0.05.

As shown in Table 2, in Comparative Example 1, the light transmittance was less than 75%. Therefore, the gas barrier film of Comparative Example 1 was not excellent in transparency. In Comparative Examples 2 to 7, the high-temperature, high-humidity WVTR exceeded 0.10 g/m ² ·day. Therefore, the gas barrier films of Comparative Examples 2 to 7 could not ensure gas barrier properties after being exposed to a high-temperature and high-humidity environment. In Comparative Examples 1 and 2, the amount of extracted ammonium ions per 1 cm ² of the sample exceeded 0.30 μg. Therefore, the gas barrier films of Comparative Examples 1 and 2 could not suppress the generation of ammonia.

From the above results, it was shown that, according to the present invention, it is possible to provide a gas barrier film that suppresses the generation of ammonia, ensures gas barrier properties even when exposed to a high-temperature, high-humidity environment, and has excellent transparency. .

10, 20, 30, 40, 50 gas barrier film 11 transparent film substrate 12, 21, 41 gas barrier layer 13 silicon oxynitride layer 31 hard coat layer 51 adhesive layer 100 polarizing plate with gas barrier layer 101 polarizing plate 200 image display device 202 Image display cell BL Baseline SP Si2p spectrum curve

Claims (11)

A gas barrier film comprising a transparent film substrate and a gas barrier layer disposed directly or indirectly on at least one main surface of the transparent film substrate,
The gas barrier layer has a silicon oxynitride layer containing oxygen, nitrogen and silicon as constituent elements,
The composition of the silicon oxynitride contained in the silicon oxynitride layer is represented by the general formula SiO _x N _y ,
x and y in the general formula SiO _x N _y satisfy the relationships of 0.30<x<1.20, 0.40<y<0.80 and 0.50<x/y<2.30,
In the Si2p spectrum of the silicon oxynitride layer obtained by X-ray photoelectron spectroscopy, the area of the region between the Si2p spectrum curve and the baseline in the range of binding energy 95 eV or more and 110 eV or less is defined as S1, and the waveform is obtained from the Si2p spectrum A gas barrier film that satisfies the relationship of 0.05≦S2/S1≦0.30, where S2 is the area of a peak derived from a Si—Si bond separated by analysis. The gas barrier film according to claim 1, wherein said S2/S1 is 0.15 or more and 0.30 or less. The gas barrier film according to claim 1 or 2, wherein said x/y is 2.00 or less. The gas barrier film according to any one of claims 1 to 3, wherein the silicon oxynitride layer has a thickness of 10 nm or more and 200 nm or less. The gas barrier film according to any one of claims 1 to 4, further comprising a hard coat layer arranged between the transparent film substrate and the gas barrier layer. The gas barrier film according to any one of claims 1 to 5, further comprising a pressure-sensitive adhesive layer disposed on the side of the gas barrier layer opposite to the transparent film substrate. A method for producing a gas barrier film according to any one of claims 1 to 6,
A method for producing a gas barrier film, comprising the step of introducing trisilylamine, a nitrogen source and an oxygen source into a chamber of a film forming apparatus and forming the silicon oxynitride layer by a chemical vapor deposition method. A polarizing plate with a gas barrier layer, comprising the gas barrier film according to any one of claims 1 to 6 and a polarizer. An image display device comprising the gas barrier film according to any one of claims 1 to 6 and an image display cell. An image display device comprising the gas barrier layer-attached polarizing plate according to claim 8 and an image display cell. 11. The image display device according to claim 9, wherein said image display cell includes an organic EL element.

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