WO2015083681A1 - Gas barrier film and production method therefor - Google Patents

Abstract

The present invention addresses the problem of providing a gas barrier film that makes it possible to suppress the occurrence of heat damage to a substrate and has excellent gas barrier performance and flexibility. This gas barrier film is characterized by having a gas barrier layer on at least one surface of a flexible substrate, wherein the gas barrier layer is deposited using a plasma chemical vapor deposition method that uses a plasma generated by applying a voltage between opposing roller electrodes that have at least a magnetic field generation member that generates a magnetic field, and the gas barrier layer satisfies all the requirements (1)-(3) below. (1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements. (2) The ratio (C/O) of the carbon amount in relation to the oxygen amount in the gas barrier layer changes continuously, being inclined in relation to the layer thickness direction. (3) The number of peaks in the ratio (C/O) of the carbon amount in relation to the oxygen amount in the layer thickness direction for one deposition process is 2.

Description

Gas barrier film and method for producing the same

The present invention relates to a gas barrier film and a method for producing the same, and more particularly relates to a gas barrier film that suppresses the occurrence of thermal damage to a substrate and has excellent gas barrier performance and flexibility and a method for producing the same.

Conventionally, a gas barrier film in which a thin film (gas barrier layer) containing a metal oxide such as aluminum oxide, magnesium oxide, or silicon oxide is formed on the surface of a plastic substrate or film prevents deterioration due to various gases such as water vapor and oxygen. Therefore, it is used in applications for packaging articles that require shutoff of various gases. In addition to the packaging applications described above, in order to prevent alteration due to various gases, it is used for sealing electronic devices such as solar cells, liquid crystal display elements, organic electroluminescence elements (hereinafter also referred to as organic EL elements). Has also been used.

As a method for manufacturing such a gas barrier film, a gas barrier layer is formed on a substrate such as a film by a plasma chemical vapor deposition method (hereinafter also referred to as a plasma CVD method (CVD: Chemical Vapor Deposition)). There are known a method, a method of forming a gas barrier layer by applying a modification treatment after applying a coating liquid containing polysilazane as a main component on a substrate, or a method using them together (for example, Patent Document 1). ~ See 3).

In addition, it is known that a gas barrier layer capable of achieving both gas barrier performance and flexibility can be formed by forming a composition film in which the ratio of carbon amount and oxygen amount is continuously changed as the gas barrier layer ( For example, see Patent Document 4.) The apparatus used in the plasma CVD method disclosed in the patent document can converge the plasma near the counter roller electrode by using a magnetic field, and as a result, a dense gas barrier layer can be formed. It is.

While a dense film can be formed by converging plasma with a magnetic field in this way, a base material having low heat resistance, a thin film base material, or a wide base material due to heat of the plasma is wrinkled or deformed due to thermal damage. It has been found that the composition of the gas barrier layer formed on the base material is changed accordingly, and the desired gas barrier performance and flexibility cannot be obtained.

JP 2009-255040 A Japanese Patent No. 3511325 JP 2012-106421 A International Publication No. 2012/046767

The present invention has been made in view of the above problems and situations, and its solution is to suppress the occurrence of thermal damage to the base material and to provide a gas barrier film excellent in gas barrier performance and flexibility and a method for producing the same. Is to provide.

In order to solve the above problems, the present inventor, in the process of examining the cause of the above problems, the gas barrier layer of the gas barrier film has been formed by a specific plasma chemical vapor deposition method, and It has been found that when the gas barrier layer satisfies all the specific requirements, the occurrence of thermal damage to the substrate is suppressed, and a gas barrier film excellent in gas barrier performance and flexibility can be obtained.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. A gas barrier film having a gas barrier layer on at least one surface of a flexible substrate,
The gas barrier layer is formed by a plasma chemical vapor deposition method using plasma generated by applying a voltage between opposing roller electrodes having at least a magnetic field generating member for generating a magnetic field, and the gas barrier A gas barrier film, wherein the layer satisfies all of the following requirements (1) to (3):
(1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
(2) The ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer continuously changes with a gradient in the layer thickness direction.
(3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.

2. The difference between the maximum value of the ratio (C / O) of the carbon amount to the oxygen amount and any one of the minimum values on both sides thereof is 0.05 or more. Gas barrier film.

3. A method for producing a gas barrier film in which a gas barrier layer satisfying all of the following requirements (1) to (3) is formed on at least one surface of a flexible substrate,
Step (i): A step of feeding the belt-shaped flexible substrate from the feed roller and transporting it with the transport roller,
Step (ii): The flexible base material is conveyed while being brought into contact with each of the counter roller electrodes having a magnetic field generating member for generating a magnetic field, and a film forming gas is applied between the electrodes while applying a voltage to the counter roller electrode. And performing a plasma discharge to change the plasma discharge intensity in the vicinity of the surface of the counter roller electrode and forming a gas barrier layer by a plasma chemical vapor deposition method on the flexible substrate. ,
Step (iii): a step of winding a gas barrier film having the gas barrier layer formed on the flexible substrate with a winding roller while being transported by a transport roller, Method.
(1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
(2) The ratio (C / O) of the carbon amount to the oxygen amount contained in the gas barrier layer continuously changes with a gradient with respect to the layer thickness direction.
(3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.

By the above means of the present invention, it is possible to provide a gas barrier film excellent in gas barrier performance and flexibility, and a method for producing the same, by suppressing the occurrence of thermal damage to the substrate.

The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

The apparatus used in the plasma chemical vapor deposition method disclosed in International Publication No. 2012/046767 can focus the plasma near the counter roller electrode by using a magnetic field, and as a result, a dense gas barrier. Layers can be formed.

Since the apparatus has a structure having a magnetic field generating member having an N pole and an S pole in each of a pair of opposed roller electrodes, a region having a strong and weak plasma discharge intensity exists between the pair of opposed roller electrodes by the magnetic field. And the composition of the gas barrier layer can be continuously changed depending on the region. However, if the plasma discharge intensity is strong or weak, it is presumed that at the same time, a temperature distribution tends to occur on the surface of the base material, and the temperature distribution tends to cause wrinkles and deformations on the base material. In particular, in the case of a base material with low heat resistance, a thin film base material, or a wide base material, wrinkles and deformation are likely to occur due to thermal damage.

The present inventor has examined the above problem in detail, and in the case of a gas barrier layer produced in a conventional example using the apparatus, the ratio of the carbon amount to the oxygen amount in the layer thickness direction (C / C) in the gas barrier layer. O), more than two peaks were observed in one film forming process, and in such a case, it was found that thermal damage to the substrate occurred due to the influence of the intensity of the plasma discharge intensity. .

In the present invention, the number of peaks of the carbon amount ratio (C / O) to the oxygen amount in the layer thickness direction can be reduced to two, thereby reducing the influence of the intensity of the plasma discharge intensity. It is assumed that the occurrence of thermal damage can be suppressed.

Example of configuration of gas barrier film of the present invention An example of another constitution of the gas barrier film of the present invention Schematic showing an example of gas barrier film manufacturing equipment Enlarged view of film formation space of gas barrier film manufacturing equipment Schematic showing the definition of peaks in the carbon / oxygen ratio distribution curve An example of the carbon / oxygen ratio distribution curve in the thickness direction of the layer according to the XPS depth profile of the gas barrier layer of the embodiment according to the present invention Example of carbon / oxygen ratio distribution curve in the layer thickness direction by XPS depth profile of gas barrier layer of comparative example

The gas barrier film of the present invention is a gas barrier film having a gas barrier layer on at least one surface of a flexible substrate, wherein the gas barrier layer has a magnetic field generating member that generates at least a magnetic field. A film is formed by a plasma chemical vapor deposition method using plasma generated by applying a voltage therebetween, and the gas barrier layer satisfies all the requirements (1) to (3). And This feature is a technical feature common to the inventions according to claims 1 to 3.

Furthermore, the difference between the maximum value of the ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer and the minimum value of any one of the adjacent minimum values is 0.05 or more. Since a gas barrier film having better performance and flexibility is obtained, it is preferable.

In the method for producing a gas barrier film for producing a gas barrier film of the present invention, a gas barrier layer satisfying all the requirements (1) to (3) is formed on at least one surface of a flexible substrate. A method for producing a gas barrier film, comprising:
Step (i): A step of feeding the belt-shaped flexible substrate from the feed roller and transporting it with the transport roller,
Step (ii): The flexible base material is conveyed while being brought into contact with each of the counter roller electrodes having a magnetic field generating member for generating a magnetic field, and a film forming gas is applied between the electrodes while applying a voltage to the counter roller electrode. And performing a plasma discharge to change the plasma discharge intensity in the vicinity of the surface of the counter roller electrode and forming a gas barrier layer by a plasma chemical vapor deposition method on the flexible substrate. ,
Step (iii): a step of winding the gas barrier film having the gas barrier layer formed on the flexible substrate with a take-up roller while being carried by a take-up roller, and gas barrier performance and bending Gas barrier film excellent in productivity can be produced with high productivity.

Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In the present application, “˜” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

<< Outline of Gas Barrier Film of the Present Invention >>
The gas barrier film of the present invention is a gas barrier film having a gas barrier layer on at least one surface of a flexible substrate, wherein the gas barrier layer has a magnetic field generating member that generates at least a magnetic field. The film is formed by a plasma chemical vapor deposition method using plasma generated by applying a voltage therebetween, and the gas barrier layer satisfies all of the following requirements (1) to (3) And
(1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
(2) The ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer continuously changes with a gradient in the layer thickness direction.
(3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.

The “plasma chemical vapor deposition method using plasma generated by applying a voltage between opposed roller electrodes having a magnetic field generating member for generating a magnetic field” is simply referred to as “plasma CVD method between roller electrodes” in the present application. Or, more simply, “plasma CVD method”.

Here, the ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer is specifically profiled by a carbon / oxygen ratio distribution curve. The carbon / oxygen distribution ratio curve is a continuous plot in which the distance (L) from the gas barrier layer surface according to the present invention is plotted on the horizontal axis and the ratio of carbon content to the oxygen content (C / O) is plotted on the vertical axis. A distribution curve. Thus, a “mountain” (or “valley”) occurs when the curve changes continuously with a slope.

Measurement of the silicon content, oxygen content, and carbon content with respect to the distance (L) from the gas barrier layer surface is performed by the element distribution measurement in the depth direction (hereinafter also referred to as XPS depth profile) by the following X-ray photoelectron spectroscopy. Can do.

≪X-ray photoelectron spectroscopy: XPS depth profile≫
The amount of silicon, the amount of oxygen, and the amount of carbon of the gas barrier layer according to the present invention can be measured by combining X-ray photoelectron spectroscopy (XPS) measurement with rare gas ion sputtering such as argon. It can be obtained by so-called XPS depth profile measurement in which surface composition analysis is sequentially performed while being exposed. The distribution curve of each element and the carbon / oxygen ratio distribution curve obtained by such XPS depth profile measurement, for example, the vertical axis is the atomic ratio (at%) of each element, or the ratio of the carbon amount to the oxygen amount (C / O), and the horizontal axis can be created as the etching time (sputtering time). In the element distribution curve with the horizontal axis as the etching time, the etching time is generally correlated with the distance (L) in the layer thickness direction from the surface of the gas barrier layer according to the present invention. As the distance (L) in the layer thickness direction from the gas barrier layer surface ”, the distance from the gas barrier layer surface calculated from the relationship between the etching rate and the etching time employed in the XPS depth profile measurement (ie, SiO ₂ Equivalent layer thickness (nm) = (etching time (sec) × etching rate (nm / sec)) In the present invention, the SiO ₂ equivalent layer thickness (nm) is the sputter depth (nm). Also called.

In the present invention, a distribution curve representing the atomic ratio (at%) of each element and a carbon / oxygen ratio distribution curve representing the ratio of the carbon amount to the oxygen amount (C / O) represent the silicon amount, oxygen under the following measurement conditions: It was created by measuring the amount and carbon amount.

[Measurement condition]
Etching ion species: Argon (Ar ⁺ )
Etching rate (SiO ₂ thermal oxide equivalent value): 0.05 nm / sec
Etching interval (SiO ₂ equivalent) (data plot interval): SiO ₂ equivalent layer thickness of gas barrier layer ÷ 10 ÷ TR number (number of counter roller electrodes) (nm)
X-ray photoelectron spectrometer: Model “VG Theta Probe”, manufactured by Thermo Fisher Scientific
Irradiation X-ray: Single crystal spectroscopy AlKα
X-ray spot and size: 800 × 400 μm oval.

The atomic ratio (at%) of each element is the ratio of the amount of carbon to the total amount of silicon, oxygen and carbon (100 at%), the “carbon atomic ratio (at%)”, the total amount of silicon, oxygen and carbon. The ratio of the oxygen content to the oxygen ratio is expressed as “oxygen atomic ratio (at%)”, and the ratio of the silicon content relative to the total amount of silicon, oxygen and carbon is expressed as “silicon atomic ratio (at%)”. (at%) are plotted with respect to the distance (L) from the surface of the gas barrier layer to be a silicon distribution curve, an oxygen distribution curve, and a carbon distribution curve, respectively.

<< Configuration of Gas Barrier Film of the Present Invention >>
Although the structure of the gas barrier film of this invention is not specifically limited, FIG. 1A shows an example. The gas barrier film 10 a is a gas barrier film in which the gas barrier layer 3 is laminated on the flexible substrate 1. In that case, providing the clear hard coat layer 2 functioning as a smooth layer between the flexible substrate 1 and the gas barrier layer 3 improves the adhesion between the substrate and the gas barrier layer, This is a preferred mode in order to make the unevenness of the interface difficult to affect the gas barrier layer which is a thin layer.

Moreover, the gas barrier film 10b of this invention which is another aspect is equipped with the clear hard-coat layer 2 which is a smooth layer on the flexible base material 1, as shown to FIG. 1B, for example, The clear hard coat It is also preferable that the gas barrier layer 3 is laminated on the layer 2 and the bleed-out preventing layer 4 is provided on the surface of the flexible substrate 1 opposite to the surface having the gas barrier layer 3. Furthermore, a second gas barrier layer 5 containing a metal oxide may be laminated on the gas barrier layer 3. An overcoat layer 6 may be laminated on the second gas barrier layer 5.

The “gas barrier property” as used in the present invention is, for example, a water vapor transmission rate measured by a method according to JIS K 7129-1992, or an oxygen transmission rate measured by a method according to JIS K 7126-1987. Indicated. In general, if the water vapor transmission rate is 1 g / m ² / day or less or the oxygen transmission rate is 1 ml / m ² / day / atm or less, it is said to have gas barrier properties. Furthermore, if the water vapor transmission rate is 1 × 10 ⁻² g / m ² / day or less, it is said to have a high gas barrier property and can be used for electronic devices such as organic EL, electronic paper, solar cells, and LCDs.

≪Gas barrier layer≫
The gas barrier layer according to the present invention is a flexible base material by performing a film forming process by a plasma CVD method while supplying a film forming gas between a pair of opposed roller electrodes having at least a magnetic field generating member for generating a magnetic field. The gas barrier layer is characterized in that it satisfies all the following requirements (1) to (3).
(1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
(2) The ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer continuously changes with a gradient in the layer thickness direction.
(3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.

The thickness of the gas barrier layer according to the present invention is not particularly limited, but it is usually preferably in the range of 20 to 1000 nm in order to improve the gas barrier performance and make it difficult to cause defects. The gas barrier layer according to the present invention may be a single layer or a laminated structure composed of a plurality of sublayers. In this case, the number of sublayers is preferably 2 to 30. Moreover, each sublayer may have the same composition or a different composition. In that case, the layer thickness per gas barrier layer according to the present invention is more preferably in the range of 20 to 500 nm, and more preferably in the range of 30 to 300 nm from the viewpoint of improving flexibility. .

The following explains each requirement.

(A) Constituent elements: requirements (1)
The gas barrier layer according to the present invention is characterized by containing silicon, oxygen, and carbon as constituent elements as the requirement (1).

In the gas barrier layer according to the present invention, carbon is present in addition to silicon and oxygen. Among these, the presence of silicon and oxygen can impart gas barrier properties, and the presence of carbon can impart flexibility to the gas barrier layer.

The gas barrier layer according to the present invention comprises a silicon distribution curve indicating the relationship between the distance (L) from the surface of the gas barrier layer according to the present invention in the layer thickness direction of the gas barrier layer according to the present invention and the silicon atomic ratio, L In the oxygen distribution curve showing the relationship between the oxygen atom ratio and the carbon distribution curve showing the relationship between the L and carbon atom ratio, 80% or more (upper limit: 100%) of the thickness of the gas barrier layer according to the present invention. It is preferable that the region has an order magnitude relationship represented by the following formula (A) or the following formula (B).

Formula (A) (carbon atom ratio) <(silicon atom ratio) <(oxygen atom ratio)
Formula (B) (oxygen atom ratio) <(silicon atom ratio) <(carbon atom ratio)
Here, at least 80% or more of the layer thickness of the gas barrier layer according to the present invention does not have to be continuous in the gas barrier layer, and only needs to satisfy the above-described relationship at a portion of 80% or more. .

In the above distribution curve, the relationship between the oxygen atom ratio, the silicon atom ratio, and the carbon atom ratio is more preferably satisfied in a region of at least 90% or more (upper limit: 100%) of the film thickness of the gas barrier layer, and at least 93 More preferably, it is satisfied in an area of at least% (upper limit: 100%). Further, in the region of 80% or more (upper limit: 100%) of the thickness of the gas barrier layer according to the present invention, the atomic ratio satisfies C <Si <O, and the order magnitude relationship represented by the formula (A) is satisfied. Is preferred. By satisfying such conditions, the gas barrier property and bending resistance of the obtained gas barrier film are sufficient.

The silicon atom ratio in the gas barrier layer is preferably in the range of 25 to 45 at%, and more preferably in the range of 30 to 40 at%. The oxygen atom ratio in the gas barrier layer according to the present invention is preferably in the range of 20 to 67 at%, more preferably in the range of 25 to 67 at%. Furthermore, the carbon atom ratio in the layer is preferably in the range of 3 to 50 at%, more preferably in the range of 3 to 40 at%.

As a material of the gas barrier layer according to the present invention, it is a material having a function of suppressing the ingress of gas such as water and oxygen causing deterioration of the performance of the electronic device in which the gas barrier film is used. Inorganic silicon compounds such as silicon oxide, silicon oxynitride, silicon dioxide, and silicon nitride, organic silicon compounds, and the like can be used.

In particular, the gas barrier layer is preferably formed by oxidizing or nitriding a gas in which an organosilicon compound is vaporized.

Examples of organosilicon compounds include hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propyl Examples thereof include silane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane. Of these, hexamethyldisiloxane and 1,1,3,3-tetramethyldisiloxane are preferred from the viewpoint of easy handling and excellent gas barrier properties.

These organosilicon compounds can be used singly or in combination of two or more.

(B) Film forming apparatus: requirement (2)
As described above, since the oxygen distribution state in the gas barrier layer affects the gas barrier property and the carbon distribution state affects the flexibility, the gas barrier layer includes the gas barrier layer as the requirement (2). The ratio of the carbon amount to the oxygen amount (C / O) must be continuously changed with a gradient in the layer thickness direction from the viewpoint of achieving both gas barrier properties and flexibility.

“C / O changes continuously with a gradient” means that when carbon / oxygen ratio distribution curve is obtained by plotting C / O against distance (L) from the gas barrier layer surface, Means having two extreme values. The existence of such an extreme value indicates that the presence of carbon in the layer is not uniform, and the presence of a part having a large amount of carbon partially makes the entire layer a flexible structure, and has flexibility. improves.

In the gas barrier layer according to the present invention, C / O preferably has at least three extreme values, and more preferably has at least five extreme values.

Here, the extreme value means the maximum or minimum value of C / O with respect to the distance from the surface of the gas barrier layer in the layer thickness direction of the gas barrier layer (L).

In the present invention, the maximum value is a point in C / O where the C / O value changes from increasing to decreasing with a continuous change in the distance from the surface of the gas barrier layer, and the ratio of that point is The value of the ratio of the position where the distance from the surface of the gas barrier layer in the layer thickness direction of the gas barrier layer is further changed by 5 nm from the point is reduced by 0.01 or more.

The minimum value is a point in C / O where the value of C / O changes from decreasing to increasing with a continuous change in the distance from the surface of the gas barrier layer, and more than the ratio value at that point. This means that the value of the ratio of the position where the distance from the surface of the gas barrier layer in the layer thickness direction of the gas barrier layer is further changed by 5 nm from this point increases by 0.01 or more.

“C / O continuously changes” means that the carbon / oxygen ratio distribution curve does not include a portion that changes discontinuously, specifically, a layer thickness calculated from an etching rate and an etching time. In the relationship between the distance from the surface in the direction (x, unit: nm) and C / O, the condition expressed by the following formula (1) is satisfied.

Formula (1) (d (C / O) / dx) ≦ 0.005
In order for the gas barrier layer according to the present invention to satisfy the requirement (2), it is preferable to use a film forming apparatus capable of performing the plasma CVD method described below.

A film forming apparatus for forming a gas barrier layer according to the present invention includes a pair of opposed roller electrodes for opposingly arranging a flexible substrate in a vacuum chamber, and forming a thin film layer on the flexible substrate. It is preferable that the film forming apparatus has at least one set of the following means (1) to (5).

Means (1): Supply port for supplying a film forming gas to the opposing space between the flexible substrates to be opposed to each other Means (2): Magnetic field generator for forming an endless tunnel-like magnetic field swelled in the opposing space (3): Power source for generating plasma in the opposed space Means (4): A pair of opposed roller electrodes for forming a thin film layer on the flexible substrate Means (5): Exhaust port for exhausting the film forming gas in the opposed space More specifically, as the film forming apparatus, a counter roller type film forming apparatus using a plasma CVD method is used.

Incidentally, the conventional CVD method using plasma discharge using a flat electrode (horizontal transport) type does not cause a continuous change in the concentration gradient of the carbon atom component in the gas barrier layer, so the gas barrier that is the subject of the present application. Compatibility and flexibility are difficult. The effect of the present invention is that carbon atoms are formed in a gas barrier layer formed by a plasma chemical vapor deposition method using a plasma generated by applying a voltage between opposed roller electrodes having a magnetic field generating member that generates a magnetic field. By continuously changing the concentration gradient of the components, gas barrier properties and adhesion are compatible.

As shown in FIG. 2, the film forming apparatus A includes a pair of opposed roller electrodes 21 and 22 (means (4)) in the vacuum chamber 11 and magnetic field generation provided inside the pair of opposed roller electrodes 21 and 22. At least one set of film-forming region 20 provided with apparatuses 23 and 24 (means (2)), power source 25 (means (3)), supply port 26 (means (1)) and exhaust port 27 (means (5)). Have.

The original winding roller 41 is rotatably disposed on the upstream side in the transport direction X in the vacuum chamber 11, and the winding roller 42 is rotatably disposed on the downstream side in the transport direction X. A transport roller is appropriately disposed between the members (transport rollers 43 to 46).

The film forming apparatus A conveys the long flexible substrate 1 by the opposed roller electrodes 21 and 22 and the conveying rollers 43 to 46 under reduced pressure, and the opposed roller is placed on the conveyed flexible substrate 1. A gas barrier layer is continuously formed by the electrodes 21 and 22.

The long flexible substrate 1 is preferably a film substrate, and one or more functional layers such as a smooth layer may already be formed.

The internal pressure of the vacuum chamber 11 is adjusted to a reduced pressure by the vacuum pump 50 when the gas barrier layer is formed. The term “under reduced pressure” means that the pressure in the vacuum chamber 11 is in the range of 0.01 to 20 Pa.

The pair of opposed roller electrodes 21 and 22 form a gas barrier layer as a thin film on the flexible substrate 1 by a plasma CVD method between the roller electrodes.

The surface temperature of the pair of opposed roller electrodes 21 and 22 is preferably 50 ° C. or less, and more preferably 30 ° C. or less, from the viewpoint of alleviating thermal damage to the flexible substrate 1. The electrode surface temperature is controlled by circulating a temperature-controlled heat medium (for example, water, oil, or ethylene glycol) inside the electrode, or by using a temperature sensor such as a thermocouple that incorporates a heater inside the electrode. A method using an infrared heater can be used.

Connected between a pair of opposed roller electrodes 21 and 22 arranged to face each other, a supply port 26 for supplying a film forming gas, an exhaust port 27 for evacuating the film forming gas, and a pair of opposed roller electrodes 21 and 22 The power source 25 is disposed.

Each opposing roller electrode 21 and 22 is a roller which conveys the flexible base material 1, and functions also as a pair of electrodes.

Each counter roller electrode 21 and 22 has a built-in magnetic field generator 23 and 24, respectively.

FIG. 3 is an enlarged view of the opposed roller electrodes 21 and 22.

The magnetic field generators 23 and 24 are fixed in the opposing roller electrodes 21 and 22 so as not to rotate due to the rotation of the opposing roller electrodes 21 and 22.

As the magnetic field generators 23 and 24, normal permanent magnets can be used.

The magnetic field generators 23 and 24 are devices that form an endless tunnel-like magnetic field that swells in the facing space. Since the apparatus has a structure having a magnetic field generating member having an N pole and an S pole in each of a pair of opposed roller electrodes, a region having a strong and weak plasma discharge intensity exists between the pair of opposed roller electrodes by the magnetic field. Can do. The ratio of the amount of carbon and the amount of oxygen contained in the gas barrier layer which can continuously change the carbon content of the gas barrier layer depending on the region and which is listed as the requirement (2) according to the present invention. (C / O) can be continuously changed with a gradient in the layer thickness direction.

That is, a racetrack-shaped magnetic field is formed in the vicinity of the roller surface facing the opposing space (discharge region) along the length direction of the roller axis of the opposing roller electrodes 21 and 22, and the plasma can be converged by the magnetic field.

In the generation of plasma, when a voltage is applied to the pair of opposed roller electrodes 21 and 22 by the power source 25, a discharge space is formed between the electrodes, and a film forming gas (raw material gas and When the reaction gas is supplied, plasma of the source gas is generated, and the source component is deposited on the flexible substrate 1 facing the discharge space. Since the pair of opposed roller electrodes 21 and 22 form a magnetic field by the built-in magnetic field generators 23 and 24, respectively, plasma is generated along the magnetic field lines of the magnetic field.

Further, the opposing roller electrodes 21 and 22 are arranged to face each other so that the rotation axes are parallel to each other on the same plane, and convey the flexible substrate 1 so that the surfaces on which the gas barrier layer is formed face each other. Therefore, after forming a gas barrier layer on the flexible substrate 1 by the counter roller electrode 21 upstream in the transport direction X, the gas barrier layer is formed on the flexible substrate 1 by the counter roller electrode 22 downstream in the transport direction X. Furthermore, a gas barrier layer can be formed, and the film formation rate can be further improved.

The counter roller electrodes 21 and 22 preferably have the same diameter from the viewpoint of efficiently forming a thin film.

The diameters of the counter roller electrodes 21 and 22 are preferably in the range of 50 to 1000 mm in diameter from the viewpoint of optimizing the discharge conditions and reducing the space in the vacuum chamber 11.

If the diameter φ is 100 mm or more, a sufficiently large discharge space can be formed, and a reduction in productivity can be prevented. In addition, a sufficient layer thickness can be obtained by short-time discharge, and the amount of heat applied to the flexible substrate 1 at the time of discharge can be suppressed to suppress residual stress. If the diameter φ is 1000 mm or less, the uniformity of the discharge space can be maintained, which is practical in device design.

The power source 25 supplies power to the pair of opposed roller electrodes 21 and 22.

As the power source 25, a conventionally known power source can be used for plasma generation. However, an AC power source capable of alternately inverting the polarities of the opposing roller electrodes 21 and 22 improves the film formation rate. Therefore, it is preferable.

The amount of power that the power supply 25 supplies to the pair of opposed roller electrodes 21 and 22 is preferably in the range of 1 to 200 W / cm per unit width, and more preferably in the range of 10 to 100 W / cm from the viewpoint of film quality and substrate damage. preferable. In the case of an AC power supply, the AC frequency is preferably in the range of 50 Hz to 1 MHz.

The supply port 26 supplies a film-forming gas for the gas barrier layer to the discharge space formed between the opposed roller electrodes 21 and 22.

The supply port 26 is equidistant from the opposing roller electrodes 21 and 22 and is disposed above the discharge space, and the exhaust port 27 is equidistant from the opposing roller electrodes 21 and 22 and the bottom surface of the vacuum chamber 11. Of these, it is disposed in the lower region of the discharge space. Thereby, the film forming gas supplied from the supply port 26 passes through the discharge space between the opposed roller electrodes 21 and 22 and is discharged from the exhaust port 27.

The original winding roller 41 is also called an unwinder and unwinds the roll body of the flexible substrate 1.

The transport rollers 43 to 46 are also called guide rollers, and take up the unrolled flexible base material 1 from the original winding roller 41 to the pair of counter roller electrodes 21 and 22 and from the pair of counter roller electrodes 21 and 22. Convey continuously to the roller 42.

The take-up roller 42 is also called a winder, and takes up the flexible substrate 1 formed into a film.

As each roller, a conventionally known roller can be used, and for example, a metal or alloy roller can be used. A coat layer may be provided on each roller surface.

After forming the gas barrier layer, the film forming apparatus A having the above configuration reverses the rotation direction of each roller so that the conveyance direction X of the flexible substrate 1 is reversed, and further forms a plurality of gas barrier layers. You can also

(C) Film formation method: requirement (3)
In the gas barrier layer according to the present invention, as a requirement (3), the number of peaks in the layer thickness direction of C / O (carbon / oxygen ratio distribution curve) per film deposition process by the plasma CVD method is two. It is a feature.

The “mountain” means that, in C / O (carbon / oxygen ratio distribution curve), the difference in C / O between the maximum value and one of the minimum values adjacent to both is 0.01 or more. At some point, the maximum value (peak) is defined as the “mountain” of the carbon / oxygen ratio distribution curve. Therefore, “the number of peaks is two” means that the number of local maximum values (peaks) is two per one film forming process.

The difference in C / O between the maximum value and any one of the minimum values adjacent to the maximum value is preferably 0.02 or more, more preferably 0.05 or more, and still more preferably 0.1 or more. is there. By having such a C / O difference, sufficient flexibility can be imparted to the gas barrier layer.

FIG. 4 is a schematic diagram showing “mountains” in C / O (carbon / oxygen ratio distribution curve).

“Per film forming process” means that in the film forming apparatus that performs plasma CVD including the counter roller electrode, a flexible substrate passes through each of the pair of counter roller electrodes, and a gas barrier layer is formed. The process is referred to as “one film formation process”.

That is, referring to FIG. 2, it refers to a process in which the flexible substrate 1 passes through a pair of opposed roller electrodes 21 and 22 and a gas barrier layer is formed by plasma CVD.

Accordingly, when a plurality of gas barrier layers having a desired thickness are stacked by performing a plurality of film forming processes, for example, a plurality of film forming apparatuses are connected to form a plurality of films (tandem film forming apparatus). It is also preferable to carry out the film formation process again by conveying the film-formed gas barrier film wound up by the winder in the reverse direction, or to repeat the film formation process a plurality of times.

The method for producing a gas barrier layer according to the present invention preferably basically includes the following steps (i) to (iii).

Step (i): A step of feeding the belt-shaped flexible substrate from the feed roller and transporting it with the transport roller,
Step (ii): The flexible base material is conveyed while being brought into contact with each of the counter roller electrodes having a magnetic field generating member for generating a magnetic field, and a film forming gas is applied between the electrodes while applying a voltage to the counter roller electrode. And performing a plasma discharge to change the plasma discharge intensity in the vicinity of the surface of the counter roller electrode and forming a gas barrier layer by a plasma chemical vapor deposition method on the flexible substrate. ,
Step (iii): a step of winding the gas barrier film having the gas barrier layer formed on the flexible substrate with a winding roller while transporting the gas barrier layer with a transport roller. Among them, the method for producing a gas barrier layer according to the present invention includes: A film forming method for forming a thin film layer on a flexible base material by disposing a flexible base material in a vacuum chamber, and having at least one set of the following steps (1) to (5) It is preferable.

Step (1): Step of supplying a film forming gas to the facing space between the flexible substrates to be opposed to each other Step (2): Step of forming an endless tunnel-like magnetic field swelled in the facing space Step (3) Step for generating plasma in the facing space Step (4): Step for forming a thin film layer on the flexible substrate by facing the flexible substrate Step (5): Film forming gas in the facing space Step of Exhausting Hereinafter, a film forming method including a step of heating before the step of forming the thin film layer will be described as a preferable aspect of the film forming method according to the present embodiment.
(A) Step of supplying a film forming gas (step (1))
In the step of supplying the film forming gas, the film forming gas for the gas barrier layer is supplied to the facing space between the flexible substrates to be opposed to each other. For example, when a gas barrier layer made of silicon oxide is formed by oxidizing a silicon compound, a silicon compound gas (raw material gas) and an oxygen gas (reaction gas) are supplied as film forming gases. As the film forming gas to be supplied, a carrier gas can be used as necessary, and a plasma generating gas can be supplied to promote the generation of plasma. Examples of the carrier gas include noble gases such as helium, argon, neon, xenon, and krypton, nitrogen gas, and the like, and examples of the plasma generating gas include hydrogen.

In the present invention, the “opposite space” refers to a space between the pair of opposed roller electrodes 21 and 22 described above (see FIG. 2). In addition, “opposing arrangement” in the flexible substrate means arranging the flexible substrate surfaces on which the thin film layers are formed so as to face each other.
(B) Step of forming a magnetic field (step (2))
In the step of forming the magnetic field, a magnetic field in which magnetic lines of force swell is generated in the vicinity of the region facing the facing space, of the peripheral surfaces of the facing roller electrodes 21 and 22. Thereby, since the plasma is easily converged, the deposition efficiency of the gas barrier layer can be improved.
(C) Step of generating plasma (step (3))
In the step of generating plasma, it is generated by supplying power to the counter roller electrodes 21 and 22 using a conventionally known power source. The plasma is generated along the magnetic field lines of the magnetic field generated in step (2). Therefore, electrons are confined in the discharge space by the electric field and magnetic field in the discharge space (opposing space), high-density plasma is generated, and the film formation rate is improved.
(D) Step of forming a thin film layer (step (4))
In the step of forming the thin film layer on the flexible base material, the plasma of the supplied source gas is generated by the plasma formed in the opposing space of the pair of opposing roller electrodes 21 and 22, and on the flexible base material. A raw material component is deposited on the thin film to form a gas barrier layer thin film.
(E) Step of exhausting the film forming gas (Step (5))
In the step of evacuating the deposition gas, residual gas that has not been used to form the gas barrier layer thin film on the flexible substrate is evacuated from the vacuum chamber.

Next, a film forming method using the film forming apparatus A will be described.

First, the roll body of the flexible substrate 1 is set on the original winding roller 41. A part of the flexible substrate 1 is unwound from the original winding roller 41, is laid over the transport rollers 43 to 46, the counter roller electrodes 21 and 22, and is taken up by the take-up roller 42.

Thereafter, the vacuum pump 50 is evacuated to reduce the pressure in the vacuum chamber 11.

After sufficiently depressurizing the inside of the vacuum chamber 11, the conveyance of the flexible base material 1 is started by each of the conveyance rollers 43 to 46 and the counter roller electrodes 21 and 22.

The conveyance speed (also referred to as line speed) of the flexible substrate 1 can be appropriately adjusted according to the type of film forming gas, the pressure in the vacuum chamber 11, and the like.

In the gas barrier layer according to the present invention, as a requirement (3), the number of peaks in the layer thickness direction of C / O (carbon / oxygen ratio distribution curve) per film deposition process by the plasma CVD method is two. As a method for controlling the number of peaks, it is preferable to control the conveyance speed of the flexible substrate 1. The conveyance speed of the flexible substrate 1 is preferably in the range of 3 to 100 m / min, and preferably in the range of 3 to 50 m / min. If it is 3 / min or more, the number of the peaks can be set to two in one film formation process, and wrinkles can be prevented from occurring in the flexible substrate 1 due to heat. If it is 100 m / min or less, it becomes easy to make the thickness of the gas barrier layer to form in a desired range.

From the viewpoint of avoiding thermal damage to the substrate and improving productivity, the conveyance speed of the flexible substrate 1 is preferably 5 m / min or more, and more preferably 10 m / min or more.

Further, as another means of setting the number of peaks to two, it is preferable to control the diameter of the counter roller electrode, and it is preferable that the diameter of the counter roller electrode is within a preferable range of φ50 to 1000 mm. Can be appropriately adjusted and controlled. In order to reduce the number of peaks to a desired number or less, the diameter φ is more preferably 50 to 700 mm, still more preferably 50 to 500 mm, and more preferably 50 to 300 mm. Particularly preferred for forming a barrier layer.

As a method for controlling the number of peaks, it is also preferable to combine the above two examples, and it is also preferable to combine the supply amount of the deposition gas, the applied power, the frequency of the AC power source, and the like as adjustment factors.

FIG. 5 is a diagram showing an example of a carbon / oxygen ratio distribution curve in the layer thickness direction according to the XPS depth profile of the gas barrier layer of the example satisfying the requirement (3). The starting point of the sputter depth (nm) represents the surface of the gas barrier layer.

The gas barrier layer having a total film thickness of about 180 nm was formed by carrying out the film forming process 6 times with the conveyance speed of the flexible substrate 1 being 3 m / min. The number of peaks per one film forming process is confirmed from FIG. 5 (one film forming process is a range of a layer thickness of about 30 nm each surrounded by a frame, and peaks a and b are Observed.)

FIG. 6 is a diagram showing an example of a carbon / oxygen ratio distribution curve in the layer thickness direction according to the XPS depth profile of the gas barrier layer of the comparative example.

The gas barrier layer having a total film thickness of about 180 nm was formed by performing the film forming process twice with the conveyance speed of the flexible substrate 1 being 1 m / min. The number of peaks per one film formation process is confirmed from FIG. 6 (one film formation process is a range of a layer thickness of about 90 nm each surrounded by a frame, and peaks a, b, c, d are observed).

As the flexible substrate 1 starts to be conveyed, a film-forming gas for the gas barrier layer is supplied from the supply port 26 between the opposed roller electrodes 21 and 22, and a voltage is applied to generate plasma. The film forming gas can be supplied together with a carrier gas for transporting the film forming gas, a plasma discharge gas, or the like, as necessary.

Next, the flexible base material 1 is conveyed to the counter roller electrode 21, and the raw material component of the gas barrier layer is deposited on the surface of the flexible base material 1. The flexible substrate 1 is sequentially transported to the transport rollers 44 and 45, and the raw material components of the gas barrier layer are further deposited by the counter roller electrode 22 to form the gas barrier layer as a thin film.

The flexible base material 1 on which the gas barrier layer is formed is conveyed by the conveying roller 46 and wound by the winding roller 42.

As described above, when a gas barrier layer is further formed on the flexible substrate 1 on which the gas barrier layer has already been provided, the film forming region 20 is further provided after the transport roller 46, and the gas is processed in the same procedure. A barrier layer can be formed.

When the gas barrier layer is further formed by reversing the conveyance direction of the flexible base material 1, the conveyance order by the conveyance rollers 43 to 46 and the counter roller electrodes 21 and 22 is reversed. A similar procedure can be followed except that the components are deposited and then further deposited by the counter roller electrode 21.

As the functional film that can be produced by the film forming apparatus A, in addition to the gas barrier film of the present invention in which a gas barrier layer is formed, an insulating film in which an insulating layer is formed, and a refractive index with respect to the substrate Examples include a reflective film in which thin films having a difference are laminated.

≪Flexible substrate≫
The flexible substrate 1 is a flexible substrate. The term “flexibility” as used herein refers to a base material that is wound around a φ (diameter) 50 mm roll and is not cracked before and after being wound with a constant tension. More preferably, it is possible to provide a more flexible gas barrier film when the base material can be wound around a φ30 mm roll.

The flexible substrate 1 is preferably a highly transparent resin. When the transparency of the resin is high and the transparency of the flexible substrate 1 is high, a gas barrier film with high transparency can be obtained, and it can be preferably used for an electronic device such as an organic EL element.

Examples of the resin include methacrylic acid ester, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC), polyarylate, and polystyrene (PS). ), Aromatic polyamide, polyetheretherketone, polysulfone, polyethersulfone, polyimide (PI), polyetherimide, and the like. Among these, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP), cycloolefin copolymer (COC) and the like are preferable from the viewpoint of cost and availability.

The flexible substrate 1 may have a configuration in which two or more of the above resins are laminated.

The flexible substrate 1 preferably has a thickness in the range of 5 to 500 μm, more preferably in the range of 10 to 250 μm, still more preferably in the range of 15 to 150 μm, and 20 A thickness in the range of ˜75 μm is particularly preferable from the viewpoint of thinning.

The width of the flexible substrate 1 is not particularly limited, but is preferably 100 mm width or more, more preferably 500 mm width or more, and even more preferably 1000 mm width or more from the viewpoint of enhancing productivity. If it is the structure of this invention, even if it uses a 1000-mm-wide flexible base material, the deformation | transformation and wrinkle generation | occurrence | production by a heat damage can be suppressed.

<Smooth layer: Clear hard coat layer>
In order for the flexible base material 1 to improve adhesiveness with the gas barrier layer formed on the flexible base material 1, the clear hard-coat layer may be formed as a smooth layer on the surface.

As the clear hard coat layer, a curable resin such as a thermosetting resin or an active energy ray curable resin curable resin can be used. Of these, active energy ray-curable resins are preferred because they are easy to mold.

The thermosetting resin is not particularly limited, and examples thereof include various thermosetting resins such as epoxy resins, cyanate ester resins, phenol resins, bismaleimide-triazine resins, polyimide resins, acrylic resins, and vinylbenzyl resins. .

The active energy ray-curable resin is a resin that is cured through a crosslinking reaction or the like by irradiation with active rays such as ultraviolet rays and electron beams.

Typical examples of the active energy ray curable resin include an ultraviolet curable resin and an electron beam curable resin, and an ultraviolet curable resin is particularly preferable.

Examples of the ultraviolet curable resin include an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, an ultraviolet curable polyol acrylate resin, and an ultraviolet curable epoxy resin. Can do.

In order for the clear hard coat layer to improve the adhesion to the flexible substrate 1, the surface of the flexible substrate 1 is irradiated with vacuum ultraviolet rays or subjected to surface treatment by corona discharge, and then the clear hard coat layer is applied. It can be formed by applying and curing a liquid.

As a coating method, a wet process such as a coating method using a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, or the like, or an inkjet method can be used.

The clear hard coat layer coating solution is suitably applied within a range of 0.1 to 40.0 μm as a wet film thickness, and preferably within a range of 0.5 to 30.0 μm. The layer thickness after drying is preferably in the range of 0.1 to 30.0 μm, more preferably in the range of 1 to 10 μm.

<Second gas barrier layer>
In the present invention, it is preferable to provide a second gas barrier layer on the gas barrier layer according to the present invention from the viewpoint of improving the gas barrier property. The second gas barrier layer is not particularly limited as long as it has gas barrier properties, but a coating film of a polysilazane-containing liquid is provided by a coating method, and vacuum ultraviolet light (VUV light) having a wavelength of 200 nm or less is applied. It is preferable to provide a second gas barrier layer formed by irradiation and modification treatment. By providing the second gas barrier layer on the gas barrier layer provided by the CVD method, minute defects remaining in the gas barrier layer can be filled with the gas barrier component of polysilazane from above, and further It is preferable because gas barrier properties and flexibility can be improved.

The thickness of the second gas barrier layer is preferably in the range of 1 to 500 nm, more preferably in the range of 10 to 300 nm. If the thickness is greater than 1 nm, gas barrier performance can be exhibited, and if it is within 500 nm, cracks are unlikely to occur in the dense silicon oxynitride film.

Polysilazane is commercially available in the form of a solution dissolved in an organic solvent, and the commercially available product can be used as a polysilazane-containing coating solution as it is. Examples of commercially available polysilazane solutions include NN120-20, NAX120-20, and NL120-20 manufactured by AZ Electronic Materials. Further, a metal alkoxide compound, a metal chelate compound, or a low molecular silazane / siloxane may be added to the polysilazane solution.

≪Electronic device≫
As described above, the gas barrier film of the present invention has excellent gas barrier properties, transparency, and bending resistance. For this reason, the gas barrier film of the present invention is a gas barrier film used for electronic devices such as packages such as electronic devices, photoelectric conversion elements (solar cell elements), organic electroluminescence (EL) elements, liquid crystal display elements, and the like. Can be used for various purposes.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
<< Preparation of flexible substrate >>
As a flexible base material (support), a roll-like polyester film with a thickness of 125 μm and a width of 1000 mm that is easily bonded on both sides (manufactured by Teijin DuPont Films Ltd., polyethylene terephthalate film, KDL86WA, Table 1 shows PET and (Abbreviated) was used as the flexible substrate 1.

<< Preparation of flexible substrate with clear hard coat layer >>
[Production of flexible substrate 1 with clear hard coat layer]
The following clear hard coat layer forming coating solution 1 is applied to the gas barrier layer installation side of the flexible substrate 1 with a wire bar so that the layer thickness after drying is 4 μm, and the clear hard coat layer (CHC And then dried at 80 ° C. for 3 minutes, and then cured under a condition of 0.5 J / cm ² air using a high-pressure mercury lamp as a curing condition to provide flexibility with a clear hard coat layer. A substrate 1 (abbreviated as CHC-PET in Table 1) was produced.

(Preparation of clear hard coat layer forming coating solution 1)
DIC Corporation UV curable resin Unidic V-4025 and AGC Seimi Chemical Co., Ltd. fluorine oligomer: Surflon S-651 in solid content (mass ratio) UV curable resin / S-651 = 99. Furthermore, Irgacure 184 (manufactured by BASF Japan) is added as a photopolymerization initiator, and UV curable resin / photopolymerization initiator = 95/5 as a solid content ratio (mass ratio). And further diluted with MEK as a solvent to prepare clear hard coat layer forming coating solution 1 (NV 30% by mass).

<Production of gas barrier film>
[Preparation of gas barrier film 1]
Clearing the flexible base material 1 with a clear hard coat layer using a plasma CVD apparatus using a plasma generated by applying a voltage between opposed roller electrodes having a magnetic field generating member for generating the magnetic field shown in FIG. A gas barrier layer was formed on the surface on which the hard coat layer was formed to produce a gas barrier film 1.

Specifically, it is attached to the apparatus so that the surface opposite to the clear hard coat layer formed on the above-prepared flexible base material 1 with the clear hard coat layer is a surface in contact with the counter roller electrode, The film formation process was performed 6 times under the following film formation conditions (plasma CVD conditions), and the gas barrier layer was formed under the condition of a thickness of about 180 nm, whereby the gas barrier film 1 was produced.

(Deposition conditions)
Feed rate of raw material gas (hexamethyldisiloxane, HMDSO): 1.5 sccm (Standard Cubic Centimeter per Minute) / cm
Supply amount of oxygen gas (O ₂ ): 10 sccm / cm
Degree of vacuum in the vacuum chamber: 2Pa
Applied power from the power source for plasma generation: 27 W / cm
Frequency of power source for plasma generation: 80 kHz
Conveying speed of flexible substrate with clear hard coat layer: 3m / min
Opposite roller electrode temperature: 30 ° C
Electrode diameter φ: Indicated in Table 1 as A.

[Production of gas barrier films 2 to 9]
In the production of the gas barrier film 1, as changes, ZEONOR (thickness 100 μm, width 1000 mm: expressed as COP in Table 1) and thickness, which are cycloolefin polymer films as a flexible substrate, are used. Polyester film with a clear hard coat layer with a thickness of 50 μm and a width of 1000 mm (manufactured by Teijin DuPont Films, Ltd., polyethylene terephthalate film, indicated as CHC-PET in Table 1), number of film formation treatments, film formation gas concentration , Applied power, flexible substrate conveyance speed, and counter roller electrode diameter φ (the electrode diameter is changed to 2/5 times the electrode diameter A, and is represented as the electrode diameter B in Table 1. The gas barrier films 2 to 9 shown in Table 1 were produced by appropriately changing the arrangement angle A = B.

The gas barrier film produced above was evaluated as follows.

<Measurement and evaluation of characteristic values of gas barrier film>
[Atom distribution profile (XPS data) measurement]
Under the following conditions, the XPS depth profile measurement of each gas barrier film produced was performed, and the measured values of the silicon atom weight, oxygen atom weight, and carbon atom weight were obtained.

Etching ion species: Argon (Ar ⁺ )
Etching rate (SiO ₂ thermal oxide equivalent value): 0.05 nm / sec
Etching interval (SiO ₂ equivalent value): 10 nm
X-ray photoelectron spectrometer: Model name “VG Theta Probe” manufactured by Thermo Fisher Scientific, Inc. Irradiation X-ray: Single crystal spectroscopy AlKα
X-ray spot and size: 800 × 400 μm oval.

Based on the data measured under the above conditions, the distance from the surface of the gas barrier layer (sputter depth (nm)) on the horizontal axis and the ratio of carbon amount to oxygen amount (C / O) on the vertical axis, A carbon / oxygen ratio distribution curve was created, and the number of peaks per film forming process was measured.

The gas barrier layer in which the number of peaks was two was a profile approximated to FIG. 5, and the gas barrier layer in which the number of peaks was four was a profile approximated to FIG.

Similarly, the silicon atomic ratio (at%), the oxygen atomic ratio (at%), and the carbon atomic ratio (at%) are obtained, and the silicon with respect to the distance (sputter depth (nm)) from the surface of the gas barrier layer is determined. When a distribution curve, an oxygen distribution curve, and a carbon distribution curve were prepared, the silicon atom ratio was distributed in the range of 30 to 40 at% and the oxygen atom ratio was distributed in the range of 20 to 67 at%. The carbon atom ratio was found to be distributed in the range of 3 to 50 at%.

[Substrate damage]
The flexible substrate during film formation was visually observed, the occurrence of thermal damage was observed, and the following criteria were evaluated.

○: Deformation of the base material is not observed by visual observation (the film can be formed without any problem).
Δ: Substrate deformation is slightly observed (film formation can be performed without any problem)
×: Deformation of the base material makes it impossible to continue film formation [Measurement of water vapor transmission rate (WVTR)]
The water vapor transmission rate (WVTR (g / m ² / day)) of the gas barrier film was measured using the equipment shown below.

MOCON water vapor transmission rate measuring device PERMATRAN W3 / 33
Measurement of water vapor transmission rate at 40 ° C. and 90% RH Lower detection limit: 0.01 (g / m ² / day)
In Table 1, the notation “impossible to measure” indicates that the flexible substrate was damaged by heat and WVTR could not be measured.

[Flexibility test]
The water vapor transmission rate (WVTR) was measured for a gas barrier film that had been repeatedly bent 100 times at an angle of 180 degrees in advance so as to have a radius of curvature of 10 mm.

A: No change is observed in the measured value of the water vapor transmission rate (WVTR) B: A change of 10% or less is observed in the measured value of the water vapor transmission rate (WVTR) X: A measured value of the water vapor transmission rate (WVTR) is 10 Table 1 shows the evaluation results obtained as described above.

As is clear from the results shown in Table 1, the gas barrier film having the structure defined in the present invention is less affected by the thermal damage to the flexible substrate than the comparative example, and has a gas barrier property (water vapor) It can be seen that the barrier properties are excellent.

In addition, when the above flexibility test was performed, the gas barrier film of the comparative example was inferior in flexibility due to substrate damage, but the gas barrier film of the present invention was measured by the water vapor transmission rate (WVTR) before and after the flexibility test. No change was observed, and it was confirmed that the gas barrier layer according to the present invention was formed on the flexible base material, so that it was excellent in flexibility.

The gas barrier film of the present invention is a gas barrier film that suppresses the occurrence of thermal damage to the substrate and has excellent gas barrier performance and flexibility, and is an electronic device such as an organic electroluminescence element, a solar cell, and a liquid crystal display device. It can be suitably used as a gas barrier film for use.

DESCRIPTION OF SYMBOLS 1 Flexible base material 2 Clear hard-coat layer 3 Gas barrier layer 4 Bleed-out prevention layer 5 2nd gas barrier layer 6 Overcoat layer 10a, 10b Gas barrier film 11 Vacuum chamber 20 Film-forming area | region 21, 22 Opposite roller electrode 23, 24 Magnetic field generator 25 Power supply 26 Supply port 27 Exhaust port 31 Heating device 41 Original winding roller 42 Winding roller 43 to 46 Transport roller 50 Vacuum pump A Film deposition device X Transport direction

Claims (3)

1. A gas barrier film having a gas barrier layer on at least one surface of a flexible substrate,
   The gas barrier layer is formed by a plasma chemical vapor deposition method using plasma generated by applying a voltage between opposing roller electrodes having at least a magnetic field generating member for generating a magnetic field, and the gas barrier A gas barrier film, wherein the layer satisfies all of the following requirements (1) to (3):
   (1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
   (2) The ratio (C / O) of the carbon amount to the oxygen amount of the gas barrier layer continuously changes with a gradient in the layer thickness direction.
   (3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.
2. The difference between the maximum value of the ratio (C / O) of the carbon amount to the oxygen amount and any one of the minimum values on both sides thereof is 0.05 or more. Gas barrier film.
3. A method for producing a gas barrier film in which a gas barrier layer satisfying all of the following requirements (1) to (3) is formed on at least one surface of a flexible substrate,
   Step (i): A step of feeding the belt-shaped flexible substrate from the feed roller and transporting it with the transport roller,
   Step (ii): The flexible base material is conveyed while being brought into contact with each of the counter roller electrodes having a magnetic field generating device for generating a magnetic field, and a film forming gas is applied between the electrodes while applying a voltage to the counter roller electrode. And performing a plasma discharge to change the plasma discharge intensity in the vicinity of the surface of the counter roller electrode and forming a gas barrier layer by a plasma chemical vapor deposition method on the flexible substrate. ,
   Step (iii): a step of winding a gas barrier film having the gas barrier layer formed on the flexible substrate with a winding roller while being transported by a transport roller, Method.
   (1) The gas barrier layer contains silicon, oxygen, and carbon as constituent elements.
   (2) The ratio (C / O) of the carbon amount to the oxygen amount contained in the gas barrier layer continuously changes with a gradient with respect to the layer thickness direction.
   (3) The number of peaks of the ratio (C / O) of the carbon amount to the oxygen amount in the layer thickness direction per film forming process is two.

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