JP2006264094A - Gas-barrier film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas-barrier film which is excellent and improved in adhesion. <P>SOLUTION: A gas-barrier layer containing an inorganic compound, a buffer layer containing a polyolefin as a main component and the inorganic compound incorporated in the gas-barrier layer, and a stress relaxation layer made of a polyolefin are laminated on a substrate film. In the gas-barrier film, the interface region A bordering the gas-barrier layer of the buffer layer and the interface region B bordering the stress relaxation layer of the buffer layer have different metal contents. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transparent gas barrier film used for packaging materials such as foods and pharmaceuticals, packages such as electronic devices, and display materials such as plastic substrates such as organic electroluminescence elements and liquid crystals.

  Conventionally, a gas barrier film in which a thin film of metal oxide such as aluminum oxide, magnesium oxide, silicon oxide or the like is formed on the surface of a plastic substrate or film is a packaging of articles that require blocking of various gases such as water vapor and oxygen, Widely used in packaging applications to prevent the deterioration of food, industrial products and pharmaceuticals. In addition to packaging applications, it is used in liquid crystal display elements, solar cells, organic electroluminescence (EL) substrates, and the like.

  Aluminum foil is widely used as a packaging material in such fields, but disposal after use has become a problem, and it is basically opaque and the contents can be confirmed from the outside. In addition, the display material is required to be transparent and cannot be applied at all.

  On the other hand, a base material made of polyvinylidene chloride resin or a copolymer resin of vinylidene chloride and other polymers, or a material provided with gas barrier properties by coating these vinylidene chloride resins on polypropylene resin, polyester resin, or polyamide resin However, it is widely used as a packaging material. However, since chlorine gas is generated during the incineration process, it is a problem from the viewpoint of environmental protection. Can not be applied to the field where is required.

  In particular, transparent substrates, which are being applied to liquid crystal display elements, organic EL elements, etc., have recently been required to be lighter and larger, have long-term reliability and a high degree of freedom in shape, and have curved surface display. High demands such as being possible have been added, and film base materials such as transparent plastics have begun to be used instead of glass substrates that are heavy and easily broken. For example, JP-A-2-251429 and JP-A-6-124785 disclose examples using a polymer film as a substrate of an organic electroluminescence element.

  However, a film substrate such as a transparent plastic has a problem that the gas barrier property is inferior to glass. For example, when used as a substrate of an organic electroluminescence element, if a base material with poor gas barrier properties is used, water vapor or air permeates and the organic film deteriorates, which becomes a factor that impairs light emission characteristics or durability. In addition, when a polymer substrate is used as a substrate for an electronic device, oxygen permeates the polymer substrate and permeates and diffuses into the electronic device, which deteriorates the device or is required in the electronic device. This causes a problem that the degree of vacuum cannot be maintained.

In order to solve such problems, it is known to form a metal oxide thin film on a film substrate to form a gas barrier film substrate. Gas barrier films used for packaging materials and liquid crystal display elements are known in which silicon oxide is vapor-deposited on a plastic film (Patent Document 1) and in which aluminum oxide is vapor-deposited (Patent Document 2). At present, it has only a water vapor barrier property of about ² g / m ² / day or an oxygen permeability of about ² ml / m ² / day. In recent years, due to the development of organic EL displays that require further gas barrier properties, large-sized liquid crystal displays, high-definition displays, etc., the gas barrier performance for film substrates is about 10 ^-3 g / m ² / day for water vapor barriers. Requests are rising.

  As a method to meet these demands for high water vapor barrier properties, a gas barrier film with a structure in which a dense ceramic layer and a flexible polymer layer that relieves impact from the outside are alternately laminated is proposed. (For example, see Patent Document 3). However, since the ceramic layer and the polymer layer generally have different compositions, the adhesion at each contact interface portion is deteriorated, which may cause quality deterioration such as film peeling. In particular, the deterioration of the adhesion appears remarkably under severe environments such as high temperature and high humidity or when irradiated with ultraviolet rays for a long period of time, and immediate improvement is required.

Furthermore, a molded body in which a silicon oxide thin film is formed on a polyolefin resin formed body containing an inorganic compound by an atmospheric pressure plasma CVD method has been proposed (see, for example, Patent Document 4). However, each of the disclosed methods is formed of a single layer, and there is no description or suggestion regarding a laminated structure. Also disclosed is a method of laminating and laminating a polyolefin resin that has been subjected to an oxidation treatment such as ozone treatment, flame treatment, corona treatment, etc. on a gas barrier substrate having an inorganic oxide film by an extrusion method (for example, patents). Reference 5). However, in the formation by the laminate method, the polyolefin resin layer becomes too thick and is not suitable for forming a dense thin film. Further, a gas barrier container is disclosed in which a plasma polymerized polyethylene or fluororesin film and a silicon oxide thin film formed by an atmospheric pressure plasma CVD method are laminated (see, for example, Patent Document 6). However, the method described in Patent Document 6 has a drawback that the adhesion is insufficient.
Japanese Patent Publication No.53-12953 JP 58-217344 A US Pat. No. 6,268,695 JP 2003-147129 A JP 2004-58436 A Japanese Patent Laid-Open No. 2001-261075

  This invention is made | formed in view of the said subject, The objective is to provide the gas barrier property film which was excellent in gas barrier property, and was improved in adhesiveness.

  The above object of the present invention is achieved by the following configurations.

(Claim 1)
A gas barrier layer containing an inorganic compound, a buffer layer containing an inorganic metal contained in the gas barrier layer, and a stress relaxation layer made of polyolefin are laminated on the base film, A gas barrier film, wherein the metal content is different between an interface region A with the gas barrier layer and an interface region B with the stress relaxation layer of the buffer layer.

(Claim 2)
When the content of the metal element contained in the gas barrier layer is 1.0, the metal content X1 (atm%) in the interface region A of the buffer layer is 0.6 or more and 1.1 or less, The gas barrier film according to claim 1, wherein the metal content X2 (atm%) in the interface region B of the buffer layer is 0 or more and 0.4 or less.

(Claim 3)
The gas barrier film according to claim 1 or 2, wherein at least one of the gas barrier layer, the buffer layer, and the stress relaxation layer is formed by an atmospheric pressure plasma CVD method.

(Claim 4)
The gas barrier film according to claim 1, wherein the gas barrier layer, the buffer layer, and the stress relaxation layer are formed by an atmospheric pressure plasma CVD method.

(Claim 5)
5. The inorganic compound contained in the gas barrier layer is at least one selected from silicon oxide, silicon nitride, and silicon oxynitride formed by an atmospheric pressure plasma CVD method. 2. The gas barrier film according to claim 1.

(Claim 6)
The gas barrier film according to any one of claims 1 to 5, wherein the polyolefin constituting the stress relaxation layer is at least one selected from polyethylene, polypropylene, and polybutadiene.

(Claim 7)
The gas barrier layer and the stress relaxation layer are each composed of at least two layers, and each has a buffer layer between each gas barrier layer and the stress relaxation layer. Gas barrier film.

  According to the present invention, it is possible to provide a gas barrier film having excellent gas barrier properties and improved adhesion.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  As a result of intensive studies in view of the above problems, the present inventor has found that on the base film, a gas barrier layer containing an inorganic compound, a polyolefin layer as a main component, a buffer layer containing an inorganic metal contained in the gas barrier layer, and A stress relaxation layer made of polyolefin is laminated, and the metal content is different between the interface region A of the buffer layer with the gas barrier layer and the interface region B of the buffer layer with the stress relaxation layer. As a result, the present inventors have found that a gas barrier film having high gas barrier properties and improved base material adhesion and adhesion between thin films can be obtained by using the gas barrier film.

  Hereinafter, each component of the gas barrier film of the present invention will be described in detail.

  The gas barrier film of the present invention comprises a gas barrier layer containing an inorganic compound on a base film, a buffer layer containing an inorganic metal contained in the gas barrier layer as a main component, and a stress relaxation layer comprising a polyolefin system. It is constituted by laminating.

<Base film>
First, the base film according to the present invention will be described.

  Although there is no restriction | limiting in particular as a base film used by the gas barrier film of this invention, It is preferable that it is a transparent resin base film, and a cellulose triacetate, a cellulose diacetate, a cellulose acetate propionate, or a cellulose acetate butyrate is used. Such as cellulose ester, polyester such as polyethylene terephthalate and polyethylene naphthalate, polyolefin such as polyethylene and polypropylene, polyvinylidene chloride, polyvinyl chloride, polyvinyl alcohol, ethylene vinyl alcohol copolymer, syndiotactic polystyrene, polycarbonate, norbornene resin, Polymethylpentene, polyetherketone, polyimide, polyethersulfone, polysulfone, polyetherimi , Polyamide, fluorine resin, polymethyl acrylate, and the like acrylates copolymer, etc. can.

  These materials can be used alone or in combination as appropriate. Among them, ZEONEX and ZEONOR (manufactured by ZEON CORPORATION), amorphous cyclopolyolefin resin film ARTON (manufactured by JSR Corporation), polycarbonate film pure ace (manufactured by Teijin Ltd.), and cellulose triacetate film Konicakat Commercial products such as KC4UX and KC8UX (manufactured by Konica Minolta Opto Co., Ltd.) can be preferably used.

  Moreover, the base film used for this invention is not limited to said description.

  As a film thickness of a base film, 10-200 micrometers is preferable, More preferably, it is 50-100 micrometers.

As the water vapor permeability of the gas barrier film of the present invention, the water vapor permeability measured according to the JIS K7129 B method when used for an application requiring high water vapor barrier properties such as an organic EL display and a high-definition color liquid crystal display, 1.0 g / m ² / day or less is preferable, and in the case of an organic EL display application, a growing dark spot may be generated even if it is extremely small, and the display life of the display may be extremely shortened. Therefore, the water vapor permeability is preferably less than 0.1 g / m ² / day.

  In the base film according to the present invention, the average surface roughness is in the range of 1 to 50 nm, preferably 10 to 50 nm.

  The method for imparting the average surface roughness defined in the present invention is not particularly limited. For example, an external particle addition method in which inert inorganic particles are added to the base material at the time of manufacturing the base material, added during the synthesis of the base material. In general, an internal particle deposition method for depositing a catalyst to be deposited, a method for applying a surfactant or the like to the surface of a substrate, and the like are generally used.

《Gas barrier layer》
Next, the gas barrier layer according to the present invention will be described.

  The gas barrier layer according to the present invention is a layer having an effect of blocking gas such as water vapor and oxygen, and is a thin film mainly composed of a ceramic component such as metal oxide, metal nitride oxide, metal nitride, The film thickness is approximately 5 to 300 nm, preferably 20 to 100 nm.

  The gas barrier layer according to the present invention contains an inorganic compound. Further, in the gas barrier layer according to the present invention, the inorganic compound contained in the gas barrier layer is SiOx, SiNy or SiOxNy (x = 1 to 2, y = 0 to 1 to 1) formed by an atmospheric pressure plasma CVD method to be described later. In particular, from the viewpoint of moisture permeability, light transmittance and suitability for atmospheric pressure plasma CVD described later, SiOx is preferred.

The inorganic compound according to the present invention can be obtained, for example, by combining an organic silicon compound described later with oxygen gas or nitrogen gas at a predetermined ratio to obtain a film containing at least one of O atoms and N atoms and Si atoms. it can. Although SiO ₂ is highly transparent, it has a slightly lower gas barrier property and allows water to pass therethrough, so it is more preferable that it contains N atoms. That is, when the ratio of the number of oxygen atoms and nitrogen atoms is x: y, x / (x + y) is more preferably 0.95 or less, and even more preferably 0.80 or less. Therefore, in the gas barrier layer according to the present invention, the light transmittance T is preferably 80% or more.

  Note that when the ratio of N atoms is large, the light transmittance is lowered, and SiN where x = 0 hardly transmits light. Therefore, a specific ratio of oxygen atoms and nitrogen atoms may be determined according to the application. For example, in an application that requires light transmission, such as when a film is formed on the light emitting surface side of a light emitting element in a display device, if x / (x + y) is 0.4 or more and 0.95, It is preferable because a balance between light transmittance and waterproofness can be achieved. In addition, x / (x + y) is preferably 0 or more and less than 0.4 for applications where it is preferable to absorb or shield light such as a reflection preventing film provided on the rear surface of the light emitting element of the display device.

  The gas barrier layer according to the present invention is formed by applying a raw material described later by sputtering, coating, ion assist, plasma CVD described later, plasma CVD under atmospheric pressure or pressure near atmospheric pressure described later, and the like. The plasma CVD method is preferably performed under a pressure close to atmospheric pressure. The details of the layer formation conditions of the atmospheric pressure plasma CVD method will be described later.

  The gas barrier layer obtained by the plasma CVD method under atmospheric pressure or near atmospheric pressure is made by selecting conditions such as organometallic compound, decomposition gas, decomposition temperature, and input power as raw materials (also referred to as raw materials). Carbides, metal nitrides, metal oxides, metal sulfides, metal halides, and mixtures thereof (such as metal oxynitrides, metal oxyhalides, and metal nitride carbides) can be formed separately, which is preferable.

  For example, when a silicon compound is used as a raw material compound and oxygen is used as a decomposition gas, silicon oxide is generated. Moreover, if a zinc compound is used as a raw material compound and carbon disulfide is used as the cracking gas, zinc sulfide is generated. This is because highly active charged particles and active radicals exist in the plasma space at a high density, so that multistage chemical reactions are accelerated at high speed in the plasma space, and the elements present in the plasma space are thermodynamic. This is because it is converted into an extremely stable compound in a very short time.

  As such an inorganic material, as long as it has a typical or transition metal element, it may be in a gas, liquid, or solid state at normal temperature and pressure. In the case of gas, it can be introduced into the discharge space as it is, but in the case of liquid or solid, it is used after being vaporized by means such as heating, bubbling, decompression or ultrasonic irradiation. Moreover, you may dilute and use with a solvent and organic solvents, such as methanol, ethanol, n-hexane, and these mixed solvents can be used for a solvent. Since these diluted solvents are decomposed into molecular and atomic forms during the plasma discharge treatment, the influence can be almost ignored.

  However, it is preferably a compound having a vapor pressure in a temperature range of 0 ° C to 250 ° C under atmospheric pressure, and more preferably a compound exhibiting a liquid state in a temperature range of 0 ° C to 250 ° C. This is because the pressure in the plasma film forming chamber is close to atmospheric pressure, and it is difficult to send a gas into the plasma film forming chamber unless it can be vaporized under atmospheric pressure. This is because the amount fed can be managed with high accuracy. In addition, when the heat resistance of the plastic film which forms a gas barrier layer is 270 degrees C or less, it is preferable that it is a compound which has a vapor pressure from the plastic film heat resistant temperature to the temperature of 20 degrees C or less.

As such an organometallic compound,
As silicon compounds, silane, tetramethoxysilane, tetraethoxysilane, tetra n-propoxysilane, tetraisopropoxysilane, tetra n-butoxysilane, tetrat-butoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, Diphenyldimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, phenyltriethoxysilane, (3,3,3-trifluoropropyl) trimethoxysilane, hexamethyldisiloxane, bis (dimethylamino) dimethylsilane, bis (dimethyl Amino) methylvinylsilane, bis (ethylamino) dimethylsilane, N, O-bis (trimethylsilyl) acetamide, bis (trimethylsilyl) carbodiimide, diethylaminoto Methylsilane, dimethylaminodimethylsilane, hexamethyldisilazane, hexamethylcyclotrisilazane, heptamethyldisilazane, nonamethyltrisilazane, octamethylcyclotetrasilazane, tetrakisdimethylaminosilane, tetraisocyanatosilane, tetramethyldisilazane, tris ( Dimethylamino) silane, triethoxyfluorosilane, allyldimethylsilane, allyltrimethylsilane, benzyltrimethylsilane, bis (trimethylsilyl) acetylene, 1,4-bistrimethylsilyl-1,3-butadiyne, di-t-butylsilane, 1,3 -Disilabutane, bis (trimethylsilyl) methane, cyclopentadienyltrimethylsilane, phenyldimethylsilane, phenyltrimethylsilane, propargyltri Tylsilane, tetramethylsilane, trimethylsilylacetylene, 1- (trimethylsilyl) -1-propyne, tris (trimethylsilyl) methane, tris (trimethylsilyl) silane, vinyltrimethylsilane, hexamethyldisilane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane , Hexamethylcyclotetrasiloxane, M silicate 51, and the like.

  Examples of the titanium compound include titanium methoxide, titanium ethoxide, titanium isopropoxide, titanium tetraisoporooxide, titanium n-butoxide, titanium diisopropoxide (bis-2,4-pentanedionate), titanium. Examples thereof include diisopropoxide (bis-2,4-ethylacetoacetate), titanium di-n-butoxide (bis-2,4-pentanedionate), titanium acetylacetonate, and butyl titanate dimer.

  Zirconium compounds include zirconium n-propoxide, zirconium n-butoxide, zirconium t-butoxide, zirconium tri-n-butoxide acetylacetonate, zirconium di-n-butoxide bisacetylacetonate, zirconium acetylacetonate, zirconium acetate, Zirconium hexafluoropentanedioate and the like can be mentioned.

  Examples of the aluminum compound include aluminum ethoxide, aluminum triisopropoxide, aluminum isopropoxide, aluminum n-butoxide, aluminum s-butoxide, aluminum t-butoxide, aluminum acetylacetonate, and triethyldialuminum tri-s-butoxide. Can be mentioned.

  The boron compounds include diborane, tetraborane, boron fluoride, boron chloride, boron bromide, borane-diethyl ether complex, borane-THF complex, borane-dimethyl sulfide complex, boron trifluoride diethyl ether complex, triethylborane, trimethoxy. Examples include borane, triethoxyborane, tri (isopropoxy) borane, borazole, trimethylborazole, triethylborazole, triisopropylborazole, and the like.

  Examples of tin compounds include tetraethyltin, tetramethyltin, di-n-butyltin diacetate, tetrabutyltin, tetraoctyltin, tetraethoxytin, methyltriethoxytin, diethyldiethoxytin, triisopropylethoxytin, diethyltin, Dimethyltin, diisopropyltin, dibutyltin, diethoxytin, dimethoxytin, diisopropoxytin, dibutoxytin, tin dibutyrate, tin diacetoacetonate, ethyltin acetoacetonate, ethoxytin acetoacetonate, dimethyltin diacetoacetonate Examples of tin halides such as tin hydrogen compounds include tin dichloride and tin tetrachloride.

  Other organometallic compounds include, for example, antimony ethoxide, arsenic triethoxide, barium 2,2,6,6-tetramethylheptanedionate, beryllium acetylacetonate, bismuth hexafluoropentanedionate, dimethylcadmium, calcium 2,2,6,6-tetramethylheptanedionate, chromium trifluoropentanedionate, cobalt acetylacetonate, copper hexafluoropentanedionate, magnesium hexafluoropentanedionate-dimethyl ether complex, gallium ethoxide, tetraethoxygermane , Tetramethoxygermane, hafnium t-butoxide, hafnium ethoxide, indium acetylacetonate, indium 2,6-dimethylaminoheptanedionate Ferrocene, lanthanum isopropoxide, lead acetate, tetraethyl lead, neodymium acetylacetonate, platinum hexafluoropentanedionate, trimethylcyclopentadienylplatinum, rhodium dicarbonylacetylacetonate, strontium 2,2,6,6-tetramethyl Examples include heptanedionate, tantalum methoxide, tantalum trifluoroethoxide, tellurium ethoxide, tungsten ethoxide, vanadium triisopropoxide oxide, magnesium hexafluoroacetylacetonate, zinc acetylacetonate, and diethylzinc.

  In addition, as a decomposition gas for decomposing a raw material gas containing these metals to obtain an inorganic compound, hydrogen gas, methane gas, acetylene gas, carbon monoxide gas, carbon dioxide gas, nitrogen gas, ammonia gas, nitrous oxide Examples include gas, nitrogen oxide gas, nitrogen dioxide gas, oxygen gas, water vapor, fluorine gas, hydrogen fluoride, trifluoroalcohol, trifluorotoluene, hydrogen sulfide, sulfur dioxide, carbon disulfide, and chlorine gas.

  Various metal carbides, metal nitrides, metal oxides, metal halides, and metal sulfides can be obtained by appropriately selecting a source gas containing a metal element and a decomposition gas.

  The refractive index of the gas barrier layer obtained using the above raw materials is, for example, 1.67 for the aluminum oxide layer, 1.46 for the silicon oxide layer, and 1 for the magnesium fluoride layer. .38 etc.

  The gas barrier layer according to the present invention preferably has high light permeability and high gas barrier performance when incorporated in the gas barrier film of the present invention, and means for forming a gas barrier layer having both high light permeability and high gas barrier performance As one of them, a layer can be formed so that at least two kinds of metal elements are included in the layer. In addition, the two metal elements are preferably metal elements derived from the organometallic compound.

  In order to obtain a gas barrier layer having a desired refractive index, a film in which an inorganic substance is mixed is prepared, a mixing ratio of mixing two or more source gases containing a metal element is changed, and a decomposition gas. It is conceivable to change the mixing ratio of mixing two or more of these, but it is advantageous to tilt the metal element because the refractive index can be greatly changed. In addition, it is not preferable to mix two or more kinds of cracked gas because a reaction may occur between the cracked gases (for example, water is generated from hydrogen gas and oxygen gas).

  A discharge gas that tends to be in a plasma state is mixed with these reactive gases, and the gas is sent to the plasma discharge generator. As the discharge gas, there is a gas that easily causes a discharge when an electric field is applied, and does not generate a reaction product and does not remain in the film by itself even when excited. preferable. As such a discharge gas, nitrogen gas and / or 18th group atom of the periodic table, specifically, helium, neon, argon, krypton, xenon, radon, etc. are used. Among these, nitrogen, helium, and argon are preferably used. Helium is preferred because of its low discharge start voltage, and argon is preferred because it is the cheapest and most abundant rare gas. Nitrogen may remain as a contamination in the film, but is preferable because it is inexpensive and has a high film forming speed.

  A film is formed by mixing the inert gas and the reactive gas and supplying the mixed gas to a plasma discharge generator (plasma generator) as a mixed gas. Although the ratio of the inert gas and the reactive gas varies depending on the properties of the film to be obtained, the reactive gas is supplied with the ratio of the inert gas being 90.0 to 99.9% with respect to the entire mixed gas.

  The film thickness of the gas barrier layer according to the present invention can be adjusted by increasing the plasma treatment time, increasing the number of treatments, or increasing the partial pressure of the raw material compound in the mixed gas.

《Buffer layer》
The buffer layer according to the present invention is disposed between the gas barrier layer and a stress relaxation layer, which will be described later, and is characterized by containing a polyolefin as a main component and an inorganic metal contained in the gas barrier layer. The thickness of the buffer layer according to the present invention is generally in the range of 5 to 500 nm.

  Examples of the polyolefin forming the buffer layer according to the present invention include polyethylene, polypropylene, and polybutadiene.

  When used in the atmospheric pressure plasma CVD method described later, the raw material organic substance capable of plasma polymerization is preferably a hydrocarbon. For example, ethylene, propylene, or butadiene is used as a raw material gas to form polyethylene, polypropylene, or polybutadiene. It is preferable.

  The buffer layer according to the present invention is characterized by containing the inorganic metal contained in the gas barrier layer. By adopting such a configuration, the content of the inorganic metal element between the gas barrier layer and the stress relaxation layer described later is increased. It is possible to relieve rapid concentration change and improve interlayer adhesion between the gas barrier layer and the stress relaxation layer.

  Examples of the inorganic metal compound used for forming the buffer layer according to the present invention include the same compounds as those described in the gas barrier layer.

  In the formation of the buffer layer according to the present invention, the content of the inorganic metal is changed in the buffer layer, and the interface region A between the buffer layer and the gas barrier layer and the interface region B between the stress relaxation layer, The metal content is different.

  Further preferably, when the content of the metal element contained in the gas barrier layer is 1.0, the metal content X1 (atm%) in the interface region A of the buffer layer is 0.6 or more and 1.1 or less. The metal content X2 (atm%) in the interface region B of the buffer layer is preferably 0 or more and 0.4 or less.

  The interface region A of the buffer layer in the present invention refers to a region up to 10% from the surface in contact with the gas barrier layer having the entire buffer layer thickness, and the average metal content in that region is X1. Similarly, the interface region B of the buffer layer referred to in the present invention means a region up to 10% from the surface in contact with the stress relaxation layer having the entire buffer layer thickness, and the average metal content in the region is X2. did.

  The buffer layer according to the present invention is formed by a dry process such as vapor deposition, sputtering, CVD method (chemical vapor deposition), plasma CVD method, plasma CVD method performed under atmospheric pressure or near atmospheric pressure. However, in the method for producing a gas barrier film of the present invention, in order to form a buffer layer having the specific metal content profile defined above, at least one buffer layer, preferably all the buffer layers, are formed. Using a plasma CVD method carried out at atmospheric pressure or near atmospheric pressure, a polyolefin film is formed, for example, a thin film forming gas containing ethylene, propylene, butadiene, etc., and a thin film forming gas containing an inorganic metal compound By changing the supply amount as appropriate, the metal content can be changed to an arbitrary concentration in the thickness direction. It was capable of forming a buffer layer.

  In the formation of the buffer layer by the atmospheric pressure plasma CVD method that can be preferably applied to the present invention, the reactive gas is mainly mixed with a discharge gas that tends to be in a plasma state, and the gas is sent to the plasma discharge generator. As the discharge gas, it is inactive so that it is easy to cause a discharge when an electric field is applied, and it only induces a chain reaction even in an excited state and does not generate a reaction product itself and does not remain in the film. Gas is preferred. As such a discharge gas (inert gas), nitrogen gas and / or 18th group atom of the periodic table, specifically, helium, neon, argon, krypton, xenon, radon, etc. are used. Among these, nitrogen, helium, and argon are preferably used. Helium is preferred because of its low discharge start voltage, and argon is preferred because it is the cheapest and most abundant rare gas. Nitrogen may remain as a contamination in the film, but is preferable because it is inexpensive and has a high film forming speed.

  The discharge gas and the reactive gas are mixed and supplied as a mixed gas to a plasma discharge generator (plasma generator) to form a buffer layer. Although the ratio of the inert gas and the reactive gas varies depending on the properties of the film to be obtained, the reactive gas is supplied with the ratio of the inert gas being 90.0 to 99.9% with respect to the entire mixed gas.

  The film thickness of the buffer layer according to the present invention can be adjusted by increasing the plasma treatment time, increasing the number of treatments, or increasing the partial pressure of the raw material compound in the mixed gas.

  In the present invention, the specific metal atom in the gas barrier layer or the buffer layer can be analyzed using an XPS (X-ray photoelectron spectroscopy) surface analyzer. In the present invention, the XPS surface analyzer used ESCALAB-200R manufactured by VG Scientific.

  Specifically, Mg was used for the X-ray anode, and measurement was performed at an output of 600 W (acceleration voltage: 15 kV, emission current: 40 mA). The energy resolution was set to be 1.5 eV to 1.7 eV when defined by the half width of a clean Ag3d5 / 2 peak.

  The measurement was performed by first analyzing the composition of the surface of the gas barrier layer or the buffer layer and then successively etching away a layer corresponding to 10% of the thickness of the polymer layer. For the removal of the gas barrier layer or the buffer layer, it is preferable to use an ion gun that can use rare gas ions. As the ion species, He, Ne, Ar, Xe, Kr, or the like can be used. In this measurement, the polymer layer was sequentially removed using Ar ion etching.

  As a measurement, first, the range of the binding energy of 0 eV to 1100 eV was measured at a data acquisition interval of 1.0 eV to determine what elements were detected.

  Next, with respect to all the detected elements except the etching ion species, the data acquisition interval was set to 0.2 eV, and the photoelectron peak giving the maximum intensity was subjected to narrow scan, and the spectrum of each element was measured.

  The obtained spectrum is COMMON DATA PROCESSING SYSTEM manufactured by VAMAS-SCA-JAPAN (preferably Ver. 2.3 or later) so as not to cause a difference in the content calculation result due to a difference in measuring apparatus or computer. After being transferred to the top, processing was performed with the same software, and the content value of each analysis target element (carbon, oxygen, silicon, titanium, etc.) was determined as an atomic concentration (at%).

  Before performing the quantitative process, a calibration of the Scale Scale was performed for each element, and a 5-point smoothing process was performed. In the quantitative process, the peak area intensity (cps * eV) from which the background was removed was used. For the background treatment, the method by Shirley was used. For the Shirley method, see D.C. A. Shirley, Phys. Rev. , B5, 4709 (1972).

《Stress relaxation layer》
Next, the stress relaxation layer according to the present invention will be described.

  The stress relaxation layer according to the present invention is composed of polyolefin as a main component, and is preferably polyethylene, polypropylene, or polybutadiene. The film thickness of the stress relaxation layer according to the present invention is approximately 5 to 500 nm, and is a layer having a low hardness relative to the gas barrier layer.

  In addition, the stress relaxation layer according to the present invention is formed by a dry process such as vapor deposition, sputtering, CVD (chemical vapor deposition), plasma CVD, or plasma CVD performed under atmospheric pressure or pressure near atmospheric pressure. Although it can be formed, it is preferable that at least one of the stress relaxation layers, and further all the stress relaxation layers be formed by an atmospheric pressure plasma CVD method.

  The stress relaxation layer according to the present invention is characterized by comprising a polyolefin as a main component, and the raw material organic substance capable of being plasma-polymerized that can be used in the atmospheric pressure plasma CVD method is preferably a hydrocarbon, for example, It is preferable to use polyethylene, polypropylene, or polybutadiene by using ethylene, propylene, or butadiene as a raw material gas.

  In the formation of the stress relaxation layer by the atmospheric pressure plasma CVD method that can be preferably applied to the present invention, the reactive gas is mainly mixed with a discharge gas that tends to be in a plasma state, and the gas is sent to the plasma discharge generator. As the discharge gas, it is inactive so that it is easy to cause a discharge when an electric field is applied, and it only induces a chain reaction even in an excited state and does not generate a reaction product itself and does not remain in the film. Gas is preferred. As such a discharge gas (inert gas), nitrogen gas and / or 18th group atom of the periodic table, specifically, helium, neon, argon, krypton, xenon, radon, etc. are used. Among these, nitrogen, helium, and argon are preferably used. Helium is preferred because of its low discharge start voltage, and argon is preferred because it is the cheapest and most abundant rare gas. Nitrogen may remain as a contamination in the film, but is preferable because it is inexpensive and has a high film forming speed.

  The discharge gas and the reactive gas are mixed, and a film is formed by supplying the mixed gas as a mixed gas to a plasma discharge generator (plasma generator). Although the ratio of the inert gas and the reactive gas varies depending on the properties of the film to be obtained, the reactive gas is supplied with the ratio of the inert gas being 90.0 to 99.9% with respect to the entire mixed gas.

  The film thickness of the stress relaxation layer according to the present invention can be adjusted by increasing the plasma treatment time, increasing the number of treatments, or increasing the partial pressure of the raw material compound in the mixed gas.

<Configuration of gas barrier film>
In the gas barrier film of the present invention, on the base film, a gas barrier layer containing an inorganic compound, a polyolefin containing a main component, a buffer layer containing an inorganic metal contained in the gas barrier layer, and a stress relaxation layer comprising polyolefin However, as long as a buffer layer is always disposed between the gas barrier layer and the stress relaxation layer, the configuration order of the gas barrier layer and the stress relaxation layer is not particularly limited.

  Further, it is preferable that each of the gas barrier layer and the stress relaxation layer is composed of at least two layers, and each has a buffer layer between the gas barrier layer and the stress relaxation layer.

<Atmospheric pressure plasma CVD method>
Next, the atmospheric pressure plasma CVD method that can be suitably used for forming the gas barrier layer, the buffer layer, and the stress relaxation layer according to the present invention in the gas barrier film of the present invention will be described in more detail.

  The plasma CVD method is also called a plasma-assisted chemical vapor deposition method or PECVD method, and various inorganic substances can be applied in a three-dimensional form with good coverage and adhesion, and without increasing the substrate temperature too much. This is a technique capable of forming a film.

  In ordinary CVD (chemical vapor deposition), volatile and sublimated organometallic compounds adhere to the surface of a high-temperature substrate, causing a decomposition reaction due to heat, producing a thermally stable inorganic thin film. That's it. Such a normal CVD method (also referred to as a thermal CVD method) normally requires a substrate temperature of 500 ° C. or higher, and cannot be used for forming a film on a plastic substrate.

  On the other hand, in the plasma CVD method, an electric field is applied to the space in the vicinity of the substrate to generate a space (plasma space) where a gas in a plasma state exists, and a volatilized / sublimated organometallic compound is introduced into the plasma space. The inorganic thin film is formed by spraying on the base material after the decomposition reaction occurs. In the plasma space, a high percentage of gas is ionized into ions and electrons, and although the temperature of the gas is kept low, the electron temperature is very high, so this high temperature electron or low temperature Is in contact with an excited state gas such as ions and radicals, so that the organometallic compound as the raw material of the inorganic film can be decomposed even at a low temperature. Therefore, it is a film forming method that can lower the temperature of a substrate on which an inorganic material is formed and can sufficiently form a film on a plastic substrate.

  However, since the plasma CVD method needs to be ionized by applying an electric field to the gas, the film is usually formed in a reduced pressure space of about 0.101 kPa to 10.1 kPa. When forming a film, the equipment is large and the operation is complicated, and this method has a problem of productivity.

  In contrast, the atmospheric pressure plasma CVD method near atmospheric pressure that can be suitably used in the present invention does not need to be reduced in pressure and has higher productivity than the plasma CVD method under vacuum, and also has a higher plasma density. The film formation speed is high due to the high density of the film, and the average free process of the gas is very short under the high pressure condition under atmospheric pressure as compared with the normal conditions of the CVD method. Such a flat film has good optical properties and gas barrier properties. From the above, in the present invention, it is more preferable to apply the atmospheric pressure plasma CVD method than the plasma CVD method under vacuum.

  Hereinafter, an apparatus for forming a stress relaxation layer or a gas barrier layer using a plasma CVD method at or near atmospheric pressure will be described in detail.

  In the method for producing a gas barrier film of the present invention, an example of a plasma film forming apparatus used for forming a stress relaxation layer or a gas barrier layer will be described with reference to FIGS. In the figure, symbol F is a long film as an example of a substrate.

  FIG. 1 is a schematic view showing an example of a jet type atmospheric pressure plasma discharge treatment apparatus useful for the present invention.

  In addition to the plasma discharge processing apparatus and the electric field application means having two power sources, the jet type atmospheric pressure plasma discharge processing apparatus is not shown in FIG. And an electrode temperature adjusting means.

The plasma discharge processing apparatus 10 has a counter electrode composed of a first electrode 11 and a second electrode 12, and the frequency ω ₁ from the first power supply 21 is output from the first electrode 11 between the counter electrodes. A first high frequency electric field having electric field strength V ₁ and current I ₁ is applied, and a second high frequency electric field having frequency ω ₂ , electric field strength V ₂ and current I ₂ from second power source 22 is applied from second electrode 12. Is applied. The first power source 21 can apply a higher frequency electric field strength (V ₁ > V ₂ ) than the second power source 22, and the first frequency ω ₁ of the first power source 21 is higher than the second frequency ω ₂ of the second power source 22. A low frequency can be applied.

  A first filter 23 is installed between the first electrode 11 and the first power source 21 to facilitate passage of current from the first power source 21 to the first electrode 11, and current from the second power source 22. Is designed so that the current from the second power source 22 to the first power source 21 is less likely to pass through.

  In addition, a second filter 24 is installed between the second electrode 12 and the second power source 22 to facilitate passage of current from the second power source 22 to the second electrode, and from the first power source 21. It is designed to ground the current and make it difficult to pass the current from the first power source 21 to the second power source.

  A gas G is introduced into the gap (discharge space) 13 between the first electrode 11 and the second electrode 12 from a gas supply means as shown in FIG. 2 to be described later, and the first electrode 11 and the second electrode A processing space created between the lower surface of the counter electrode and the base material F by generating a discharge by applying a high-frequency electric field from 12 and blowing the gas G in a plasma state to the lower side of the counter electrode (the lower side of the paper). Is filled with plasma gas G ° and unwound from a base roll (unwinder) (not shown) to be transported, or processed onto the base material F transported from the previous process. A thin film is formed near position 14. During the thin film formation, the medium heats or cools the electrode through the pipe from the electrode temperature adjusting means as shown in FIG. Depending on the temperature of the base material during the plasma discharge treatment, the properties, composition, etc. of the thin film obtained may change, and it is desirable to appropriately control this. As the temperature control medium, an insulating material such as distilled water or oil is preferably used. During the plasma discharge treatment, it is desirable to uniformly adjust the temperature inside the electrode so that the temperature unevenness of the base material in the width direction or the longitudinal direction does not occur as much as possible.

  Since a plurality of jet-type atmospheric pressure plasma discharge treatment apparatuses can be connected in series and discharged in the same plasma state at the same time, it can be processed many times and processed at high speed. In addition, if each apparatus jets gas in a different plasma state, a laminated thin film having different layers can be formed.

  FIG. 2 is a schematic view showing an example of an atmospheric pressure plasma discharge treatment apparatus that treats a substrate between counter electrodes useful for the present invention.

  The atmospheric pressure plasma discharge processing apparatus according to the present invention is an apparatus having at least a plasma discharge processing apparatus 30, an electric field applying means 40 having two power supplies, a gas supply means 50, and an electrode temperature adjusting means 60.

  FIG. 2 shows a thin film formed by subjecting the substrate F to plasma discharge treatment between the opposing electrodes (discharge space) 32 between the roll rotating electrode (first electrode) 35 and the square tube type fixed electrode group (second electrode) 36. To do.

In the discharge space (between the counter electrodes) 32 between the roll rotating electrode (first electrode) 35 and the square tube type fixed electrode group (second electrode) 36, the roll rotating electrode (first electrode) 35 has a first power source. The first high-frequency electric field having frequency ω ₁ , electric field strength V ₁ and current I ₁ from 41, and the frequency ω ₂ and electric field strength V ₂ from the second power source 42 to the square tube fixed electrode group (second electrode) 36. A second high-frequency electric field of current I ₂ is applied.

  A first filter 43 is installed between the roll rotation electrode (first electrode) 35 and the first power supply 41, and the first filter 43 easily passes a current from the first power supply 41 to the first electrode. The current from the second power supply 42 is grounded so that the current from the second power supply 42 to the first power supply is difficult to pass. Further, a second filter 44 is provided between the square tube type fixed electrode group (second electrode) 36 and the second power source 42, and the second filter 44 is connected from the second power source 42 to the second electrode. It is designed so that the current from the first power supply 41 is grounded and the current from the first power supply 41 to the second power supply is difficult to pass.

In the present invention, the roll rotation electrode 35 may be the second electrode, and the rectangular tube-shaped fixed electrode group 36 may be the first electrode. In any case, the first power source is connected to the first electrode, and the second power source is connected to the second electrode. The first power supply preferably applies a higher frequency electric field strength (V ₁ > V ₂ ) than the second power supply. Further, the frequency has the ability to satisfy ω ₁ <ω ₂ .

The current is preferably I ₁ <I ₂ . Current I ₁ of the first high-frequency electric field is preferably ^{0.3mA / cm 2 ~20mA / cm 2} , more preferably at ^{1.0mA / cm 2 ~20mA / cm 2} . The current I ₂ of the second high-frequency electric field is preferably ^{10mA / cm 2 ~100mA / cm 2} , more preferably ^{20mA / cm 2 ~100mA / cm 2} .

  The gas G generated by the gas generator 51 of the gas supply means 50 is introduced into the plasma discharge processing vessel 31 from the air supply port 52 while controlling the flow rate.

  The base material F is unwound from the original winding (not shown) and is transported or is transported from the previous process, and the air and the like that is entrained by the base material by the nip roll 65 through the guide roll 64 is blocked. Then, while being wound while being in contact with the roll rotating electrode 35, it is transferred between the square tube fixed electrode group 36 and the roll rotating electrode (first electrode) 35 and the square tube fixed electrode group (second electrode) 36. An electric field is applied from both of them to generate discharge plasma between the counter electrodes (discharge space) 32. The base material F forms a thin film with a gas in a plasma state while being wound while being in contact with the roll rotating electrode 35. The base material F passes through the nip roll 66 and the guide roll 67 and is wound up by a winder (not shown) or transferred to the next process.

  Discharged treated exhaust gas G ′ is discharged from the exhaust port 53.

  In order to heat or cool the roll rotating electrode (first electrode) 35 and the rectangular tube type fixed electrode group (second electrode) 36 during the formation of the thin film, a medium whose temperature is adjusted by the electrode temperature adjusting means 60 is used as a liquid feed pump. P is sent to both electrodes through the pipe 61, and the temperature is adjusted from the inside of the electrode. Reference numerals 68 and 69 denote partition plates that partition the plasma discharge processing vessel 31 from the outside.

  FIG. 3 is a perspective view showing an example of the structure of the conductive metal base material of the roll rotating electrode shown in FIG. 2 and the dielectric material coated thereon.

  In FIG. 3, a roll electrode 35a is formed by covering a conductive metallic base material 35A and a dielectric 35B thereon. In order to control the electrode surface temperature during the plasma discharge treatment, a temperature adjusting medium (water, silicon oil or the like) can be circulated.

  FIG. 4 is a perspective view showing an example of the structure of the conductive metallic base material of the rectangular tube electrode and the dielectric material coated thereon.

  In FIG. 4, a rectangular tube electrode 36a has a coating of a dielectric 36B similar to that of FIG. 3 on a conductive metallic base material 36A, and the structure of the electrode is a metallic pipe. , It becomes a jacket so that the temperature can be adjusted during discharge.

  In addition, the number of the rectangular tube-shaped fixed electrodes is set in plural along the circumference larger than the circumference of the roll electrode, and the discharge area of the electrodes is a full square tube type facing the roll rotating electrode 35. It is represented by the sum of the area of the fixed electrode surface.

  The rectangular tube electrode 36a shown in FIG. 4 may be a cylindrical electrode, but the rectangular tube electrode has an effect of expanding the discharge range (discharge area) as compared with the cylindrical electrode, and thus is preferably used in the present invention. .

  3 and 4, the roll electrode 35a and the rectangular tube electrode 36a are formed by spraying ceramics as dielectrics 35B and 36B on conductive metallic base materials 35A and 36A, respectively, and then sealing the inorganic compound. Is subjected to a sealing treatment. The ceramic dielectric may be covered by about 1 mm with a single wall. As the ceramic material used for thermal spraying, alumina, silicon nitride, or the like is preferably used. Among these, alumina is particularly preferable because it is easily processed. The dielectric layer may be a lining-processed dielectric provided with an inorganic material by lining.

  Examples of the conductive metal base materials 35A and 36A include titanium metal or titanium alloy, metal such as silver, platinum, stainless steel, aluminum, and iron, a composite material of iron and ceramics, or a composite material of aluminum and ceramics. Although titanium metal or a titanium alloy is particularly preferable for the reasons described later.

  When the dielectric is provided on one of the electrodes, the distance between the opposing first electrode and second electrode is the shortest distance between the surface of the dielectric and the surface of the conductive metal base material of the other electrode. Say that. When a dielectric is provided on both electrodes, it means the shortest distance between the dielectric surfaces. The distance between the electrodes is determined in consideration of the thickness of the dielectric provided on the conductive metallic base material, the magnitude of the applied electric field strength, the purpose of using the plasma, etc. From the viewpoint of carrying out, 0.1 to 20 mm is preferable, and 0.5 to 2 mm is particularly preferable.

  Details of the conductive metallic base material and dielectric useful in the present invention will be described later.

  The plasma discharge treatment vessel 31 is preferably a treatment vessel made of Pyrex (registered trademark) glass or the like, but can be made of metal as long as it can be insulated from the electrodes. For example, polyimide resin or the like may be attached to the inner surface of an aluminum or stainless steel frame, and the metal frame may be thermally sprayed to obtain insulation. In FIG. 1, it is preferable to cover both side surfaces (up to the vicinity of the base material surface) of both parallel electrodes with an object made of the above material.

As the first power source (high frequency power source) installed in the atmospheric pressure plasma discharge processing apparatus of the present invention,
Applied power symbol Manufacturer Frequency Product name A1 Shinko Electric 3kHz SPG3-4500
A2 Shinko Electric 5kHz SPG5-4500
A3 Kasuga Electric 15kHz AGI-023
A4 Shinko Electric 50kHz SPG50-4500
A5 HEIDEN Research Laboratories 100kHz * PHF-6k
A6 Pearl Industry 200kHz CF-2000-200k
A7 Pearl Industry 400kHz CF-2000-400k
And the like, and any of them can be used.

As the second power source (high frequency power source),
Applied power supply symbol Manufacturer Frequency Product name B1 Pearl Industry 800kHz CF-2000-800k
B2 Pearl Industry 2MHz CF-2000-2M
B3 Pearl Industry 13.56MHz CF-5000-13M
B4 Pearl Industry 27MHz CF-2000-27M
B5 Pearl Industry 150MHz CF-2000-150M
And the like, and any of them can be preferably used.

  Of the above power supplies, * indicates a HEIDEN Laboratory impulse high-frequency power supply (100 kHz in continuous mode). Other than that, it is a high-frequency power source that can apply only a continuous sine wave.

  In the present invention, it is preferable to employ an electrode capable of maintaining a uniform and stable discharge state by applying such an electric field in an atmospheric pressure plasma discharge treatment apparatus.

In the present invention, the electric power applied between the electrodes facing each other supplies power (power density) of 1 W / cm ² or more to the second electrode (second high-frequency electric field) to excite the discharge gas to generate plasma. The energy is applied to the thin film forming gas to form a thin film. The upper limit value of the power supplied to the second electrode is preferably 50 W / cm ² , more preferably 20 W / cm ² . The lower limit is preferably 1.2 W / cm ² . The discharge area (cm ² ) refers to an area in a range where discharge occurs in the electrode.

Further, by supplying power (output density) of 1 W / cm ² or more to the first electrode (first high frequency electric field), the output density is improved while maintaining the uniformity of the second high frequency electric field. I can do it. Thereby, a further uniform high-density plasma can be generated, and a further improvement in film forming speed and an improvement in film quality can be achieved. Preferably it is 5 W / cm ² or more. The upper limit value of the power supplied to the first electrode is preferably 50 W / cm ² .

  Here, the waveform of the high-frequency electric field is not particularly limited. There are a continuous sine wave continuous oscillation mode called a continuous mode, an intermittent oscillation mode called ON / OFF intermittently called a pulse mode, and either of them may be adopted, but at least the second electrode side (second The high-frequency electric field is preferably a continuous sine wave because a denser and better quality film can be obtained.

  An electrode used in such a method for forming a thin film by atmospheric pressure plasma must be able to withstand severe conditions in terms of structure and performance. Such an electrode is preferably a metal base material coated with a dielectric.

In the dielectric-coated electrode used in the present invention, it is preferable that the characteristics match between various metallic base materials and dielectrics. One of the characteristics is linear thermal expansion between the metallic base material and the dielectric. The combination is such that the difference in coefficient is 10 × 10 ⁻⁶ / ° C. or less. It is preferably 8 × 10 ⁻⁶ / ° C. or less, more preferably 5 × 10 ⁻⁶ / ° C. or less, and further preferably 2 × 10 ⁻⁶ / ° C. or less. The linear thermal expansion coefficient is a well-known physical property value of a material.

As a combination of a conductive metallic base material and a dielectric whose difference in linear thermal expansion coefficient is within this range,
1: Metal base material is pure titanium or titanium alloy, dielectric is ceramic spray coating 2: Metal base material is pure titanium or titanium alloy, dielectric is glass lining 3: Metal base material is stainless steel, Dielectric is ceramic spray coating 4: Metal base material is stainless steel, Dielectric is glass lining 5: Metal base material is a composite material of ceramics and iron, Dielectric is ceramic spray coating 6: Metal base material Ceramic and iron composite material, dielectric is glass lining 7: Metal base material is ceramic and aluminum composite material, dielectric is ceramic sprayed coating 8: Metal base material is ceramic and aluminum composite material, dielectric The body has glass lining. From the viewpoint of the difference in linear thermal expansion coefficient, the above 1 or 2 and 5 to 8 are preferable, and 1 is particularly preferable.

  In the present invention, titanium or a titanium alloy is particularly useful as the metallic base material from the above characteristics. By using titanium or a titanium alloy as the metal base material, the dielectric is used as described above, so that there is no deterioration of the electrode in use, especially cracking, peeling, dropping off, etc., and it can be used for a long time under harsh conditions. Can withstand.

  The atmospheric pressure plasma discharge treatment apparatus applicable to the present invention is described in, for example, Japanese Patent Application Laid-Open No. 2004-68143, 2003-49272, International Patent No. 02/48428, etc. in addition to the above description. And an atmospheric pressure plasma discharge treatment apparatus.

  EXAMPLES 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.

<< Production of gas barrier film >>
[Production of Gas Barrier Film 1: Present Invention]
(Base film)
A polyethylene naphthalate film (PEN, Teijin-DuPont film) having a thickness of 100 μm was used.

(Atmospheric pressure plasma CVD apparatus used to form gas barrier layer, buffer layer, stress relaxation layer)
Using the atmospheric pressure plasma discharge treatment apparatus of FIG. 2, a set of a roll electrode covered with a dielectric and a plurality of rectangular tube electrodes was produced as follows.

  The roll electrode serving as the first electrode is coated with a high-density, high-adhesion alumina sprayed film by an atmospheric plasma method on a jacket roll metallic base material made of titanium alloy T64 having cooling means by cooling water, and roll diameter It was set to 1000 mmφ. On the other hand, the square electrode of the second electrode was a hollow square tube type titanium alloy T64 coated with the same dielectric material as described above under the same conditions to form an opposing square tube type fixed electrode group.

Twenty-five square tube electrodes were arranged around the roll rotating electrode with a counter electrode gap of 1 mm. The total discharge area of the rectangular tube-type fixed electrode group was 150 cm (length in the width direction) × 4 cm (length in the transport direction) × 25 (number of electrodes) = 15000 cm ² . In all cases, an appropriate filter was installed.

  During plasma discharge, the first electrode (roll rotating electrode) and the second electrode (square tube fixed electrode group) were adjusted and kept at 80 ° C., and the roll rotating electrode was rotated by a drive to form a thin film.

(Formation of gas barrier layer)
Plasma discharge was performed under the following conditions to form a gas barrier layer having a thickness of 80 nm.

<Gas conditions>
Discharge gas: Nitrogen 98.9% by volume
Thin-film forming gas: tetraethoxysilane (vaporized by mixing with argon gas using a vaporizer manufactured by Lintec Corporation) 0.1% by volume
Additive gas: 1% by volume of oxygen gas
<Gas barrier layer deposition conditions>
First electrode side power supply type A5
Electric field strength 8 kV / mm
Frequency 100kHz
Output density 1W / cm ²
Second electrode side power supply type B3
Electric field strength 0.8 kV / mm
Frequency 13.56MHz
Output density 3W / cm ²
(Formation of buffer layer)
After forming the gas barrier layer, a buffer layer was formed under the following gas conditions. The supply amounts of the thin film forming gases 1 and 2 were continuously changed under the following conditions from the start to the end of film formation.

<Gas conditions>
Discharge gas: helium 95 volume%
Thin film forming gas 1: ethylene See below Thin film forming gas 2: Tetraethoxysilane (vaporized by mixing with argon gas using a vaporizer manufactured by Lintec) See below
<Volume% at start><Volume% at end>
Thin film forming gas 1 4.96 4.99
Thin film forming gas 2 0.04 0.01
<Buffer layer deposition conditions>
<Discharge conditions> Second electrode side power supply type using only the power supply on the second electrode side Pearl Industry 13.56 MHz CF-5000-13M
Frequency 13.56MHz
Output density 5W / cm ²
Film thickness 50nm
(Formation of stress relaxation layer)
After forming the buffer layer, plasma discharge was performed under the following gas conditions to form a stress relaxation layer having a thickness of 80 nm.

<Gas conditions>
Discharge gas: Helium 94 vol%
Thin film forming gas 1: Ethylene 6% by volume
<Discharge conditions> Second electrode side power supply type using only the power supply on the second electrode side Pearl Industry 13.56 MHz CF-5000-13M
Frequency 13.56MHz
Output density 5W / cm ²
[Production of Gas Barrier Film 2: Present Invention]
In the production of the gas barrier film 1, the gas barrier was similarly changed except that the supply amounts of the thin film forming gases 1 and 2 used for forming the buffer layer were changed to the following conditions from the start to the end of the film formation. Film 2 was produced.

<Volume% at start><Volume% at end>
Thin film forming gas 1 4.955 4.995
Thin film forming gas 2 0.045 0.005
[Production of Gas Barrier Film 3: Present Invention]
In the production of the gas barrier film 1, the raw material of the thin film forming gas 1 used for forming the buffer layer is changed from ethylene to propylene, and the supply amount of the thin film forming gases 1 and 2 is changed from the start of film formation to the end. A gas barrier film 3 was produced in the same manner except that the conditions were changed to the following conditions.

<Volume% at start><Volume% at end>
Thin film forming gas 1 4.97 4.98
Thin film forming gas 2 0.03 0.02
[Production of Gas Barrier Film 4: Present Invention]
In the production of the gas barrier film 1, the gas barrier was similarly applied except that the supply amounts of the thin film forming gases 1 and 2 were changed to the conditions shown in Table 1 at each film thickness position from the start to the end of film formation. Film 4 was produced.

[Production of Gas Barrier Film 5: Present Invention]
In the production of the gas barrier film 1, the gas barrier was changed in the same manner except that the supply amounts of the thin film forming gases 1 and 2 were changed to the conditions shown in Table 2 at each film thickness position from the start to the end of film formation. Film 5 was produced.

[Production of Gas Barrier Film 6: Present Invention]
In the same manner as in the production of the gas barrier film 2, the gas barrier layer / buffer layer / stress relaxation layer / buffer layer / gas barrier layer / buffer layer / stress relaxation layer on the base film are sequentially laminated to form the gas barrier film 6 Produced.

[Production of Gas Barrier Film 7: Present Invention]
In the production of the gas barrier film 1, a gas barrier film 7 was produced in the same manner except that the gas conditions for forming the buffer layer were changed as follows.

<Volume% at start><Volume% at end>
Thin film forming gas 1 4.975 4.998
Thin film forming gas 2 0.025 0.005
[Production of Gas Barrier Film 8: Comparative Example]
(Formation of gas barrier layer)
A polyethylene naphthalate film (PEN, film made by Teijin DuPont) with a thickness of 100 μm is set in the vacuum chamber of the vacuum deposition apparatus, and after vacuum degassing to 1 × 10 ⁻⁴ Pa, tetraethoxysilane, oxygen gas A gas barrier layer having a thickness of 80 nm was formed using helium gas under conditions of an applied voltage (RF power) of 300 W and a substrate temperature of 150 ° C.

(Formation of stress relaxation layer)
Using a device similar to the above, a plasma-polymerized polyethylene film having a thickness of 80 nm was coated on the gas barrier layer using ethylene as a monomer to prepare a gas barrier film 8.

[Production of Gas Barrier Film 9: Comparative Example]
In the production of the gas barrier film 1, after forming the gas barrier layer, the gas barrier film 9 was produced in the same manner except that the buffer layer was not provided and the stress relaxation layer was directly formed.

[Production of Gas Barrier Film 10: Comparative Example]
In the production of the gas barrier film 1, a gas barrier film 10 was produced in the same manner except that the gas conditions for forming the buffer layer were changed as follows.

<Gas conditions>
Discharge gas: helium 95 volume%
Thin film forming gas 1: ethylene 4.96% by volume
Thin film forming gas 2: tetraethoxysilane (vaporized by mixing with argon gas using a vaporizer manufactured by Lintec Corporation) 0.04% by volume
[Production of Gas Barrier Film 11: Comparative Example]
In the production of the gas barrier film 6, the gas barrier film 11 was produced in the same manner except that the gas conditions for forming each buffer layer were changed as follows.

<Gas conditions>
Discharge gas: helium 95 volume%
Thin film forming gas 1: 4.96% by volume of propylene
Thin film forming gas 2: tetraethoxysilane (vaporized by mixing with argon gas using a vaporizer manufactured by Lintec Corporation) 0.04% by volume
<< Evaluation of gas barrier film >>
Each gas barrier film produced as described above was subjected to the following measurements and evaluations.

[Measurement of metal element content]
1) Metal content X of gas barrier layer
According to the above-mentioned method, the content rate of Si element in all the gas barrier layers formed was measured using an ESCALAB-200R manufactured by VG Scientific, as an XPS (X-ray photoelectron spectroscopy) surface analyzer, and the average metal content thereof The amount was X (atm%).

  2) Measurement of the metal content X1 in the interface region A and the metal content X2 in the interface region B of the buffer layer.

  For the entire buffer layer formed, similarly, as an XPS (X-ray photoelectron spectroscopy) surface analyzer, ESCALAB-200R manufactured by VG Scientific Co., Ltd. was used, and the film thickness was 10% from the surface in contact with the gas barrier layer. The content of Si element up to region A (5 nm) is measured, the average metal content A (atm) is calculated, and the metal content X1 in the interface region A when the average content of the gas barrier layer is 1.0. (Atm%) was determined.

  Similarly, the Si element content from the surface in contact with the stress relaxation layer to the 10% region B (5 nm) in thickness is measured, and the interface when the average gas barrier layer content is 1.0. The metal content X2 (atm%) in region B was determined.

[Evaluation of water vapor permeation resistance]
The water vapor transmission rate WVTR was measured according to the method defined in JIS K 7129B, and the water vapor transmission resistance was evaluated according to the following criteria.

◎: water vapor permeability is less than 0.05g / m ² / day ○: water vapor transmission rate, 0.05g / m ² / day to less than 0.10g / m ² / day △: water vapor permeability The rate is 0.10 g / m ² / day or more and less than 0.50 g / m ² / day Δ: The water vapor transmission rate is 0.50 g / m ² / day or more (Evaluation of Adhesiveness)
A cross-cut test based on JIS K 5400 was performed. On the surface of the formed thin film, using a single-edged razor, eleven cuts were made vertically and horizontally at intervals of 1 mm at 90 degrees with respect to the surface to make 100 1 mm square grids. A commercially available cellophane tape is affixed to this, and one end of the tape is peeled off vertically by hand, and the ratio of the peeled area of the thin film to the affixed tape area from the score line is measured. Evaluation was performed.

A: No occurrence of peeling was observed. B: The peeled area ratio was 0.1% or more and less than 5%. Δ: The peeled area ratio was 5% or more and less than 10%. The peeled area ratio was 10% or more and less than 20%. XX: The peeled area ratio was 20% or more. Table 3 shows the results obtained as described above.

  As is clear from the results shown in Table 3, the gas barrier film of the present invention provided with a buffer layer having the characteristics specified in the present invention is superior in gas barrier properties (water vapor barrier properties) to the comparative example and formed. It turns out that it is excellent in adhesiveness between the thin films or the base film.

It is the schematic which showed an example of the atmospheric pressure plasma discharge processing apparatus of the jet system useful for this invention. It is the schematic which shows an example of the atmospheric pressure plasma discharge processing apparatus of the system which processes a base material between counter electrodes useful for this invention. It is a perspective view which shows an example of the roll rotating electrode which has an electroconductive metal base material and the dielectric material coat | covered on it. It is a perspective view which shows an example of the structure of the electroconductive metal preform | base_material of a rectangular tube type electrode, and the dielectric material coat | covered on it.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Plasma discharge processing apparatus 11 1st electrode 12 2nd electrode 20 Electric field application means 21 1st power supply 22 2nd power supply

Claims (7)

A gas barrier layer containing an inorganic compound, a buffer layer containing an inorganic metal contained in the gas barrier layer, and a stress relaxation layer made of polyolefin are laminated on the base film, A gas barrier film, wherein the metal content is different between an interface region A with the gas barrier layer and an interface region B with the stress relaxation layer of the buffer layer. When the content of the metal element contained in the gas barrier layer is 1.0, the metal content X1 (atm%) in the interface region A of the buffer layer is 0.6 or more and 1.1 or less, The gas barrier film according to claim 1, wherein the metal content X2 (atm%) in the interface region B of the buffer layer is 0 or more and 0.4 or less. The gas barrier film according to claim 1 or 2, wherein at least one of the gas barrier layer, the buffer layer, and the stress relaxation layer is formed by an atmospheric pressure plasma CVD method. The gas barrier film according to claim 1, wherein the gas barrier layer, the buffer layer, and the stress relaxation layer are formed by an atmospheric pressure plasma CVD method. 5. The inorganic compound contained in the gas barrier layer is at least one selected from silicon oxide, silicon nitride, and silicon oxynitride formed by an atmospheric pressure plasma CVD method. 2. The gas barrier film according to claim 1. The gas barrier film according to any one of claims 1 to 5, wherein the polyolefin constituting the stress relaxation layer is at least one selected from polyethylene, polypropylene, and polybutadiene. The gas barrier layer and the stress relaxation layer are each composed of at least two layers, and each has a buffer layer between each gas barrier layer and the stress relaxation layer. Gas barrier film.

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