JPWO2015111572A1 - Gas barrier film - Google Patents

Abstract

An object of the present invention is to provide a gas barrier film having a high gas barrier property. The gas barrier film of the present invention has a gas barrier in which a first layer containing zinc oxide and silicon dioxide and a second layer containing a silicon compound are arranged on at least one surface of the polymer substrate in this order from the polymer substrate. The Si2p orbital binding energy at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is greater than the Si2p orbital binding energy in the first layer and the Si2p in the second layer. Less than orbital binding energy.

Description

  The present invention relates to a gas barrier film used as a material for packaging materials such as foods and pharmaceuticals that require high gas barrier properties, and electronic parts such as solar cells, electronic paper, and organic electroluminescence (EL) displays. .

  As a technique for improving the gas barrier property of a polymer substrate, for example, carbon oxide is used as a main component on a polymer substrate by a plasma CVD method using a gas containing an organic silicon compound vapor and oxygen, and carbon. A technique for improving gas barrier properties while maintaining transparency by forming a layer of a compound containing at least one kind of hydrogen, silicon and oxygen is disclosed (Patent Document 1 (see claims)). . Another technique for improving the gas barrier property is to form an organic layer containing an epoxy compound and a silicon-based oxide layer formed by plasma CVD on the substrate alternately, thereby causing cracks and defects due to film stress. A method of forming a gas barrier layer having a multilayer structure in which the occurrence of the above is prevented is disclosed (Patent Document 2 (see claims)).

JP-A-8-142252 JP 2003-341003 A

  However, as disclosed in Patent Document 1, in the method of forming a gas barrier layer containing silicon oxide as a main component by the plasma CVD method, the gas barrier layer is formed under the influence of unevenness on the surface of the polymer base material that is the base of the gas barrier layer. There is a problem that defects are generated inside the gas barrier layer, and high gas barrier properties cannot be obtained stably.

Further, in the method of Patent Document 2, in order to obtain a high gas barrier property with a water vapor permeability of 1.0 × 10 ⁻³ g / (m ² · 24 hr · atm) or less, several tens of layers are stacked to form a thick gas barrier. Since it is necessary to form a protective layer, cracks are likely to occur due to bending or external impact, and the gas barrier property is greatly reduced during film transport after forming the gas barrier layer, handling, cutting, bonding, etc. in subsequent processes There was a problem to do.

  In view of the background of such prior art, the present invention is intended to provide a gas barrier film capable of exhibiting a high level of gas barrier properties without being multilayered.

  The present invention is a gas barrier film in which a gas barrier layer is disposed on at least one surface of a polymer substrate, and the gas barrier layer includes a first layer containing zinc oxide and silicon dioxide, and a second layer containing a silicon compound. Are arranged in contact with each other in this order as viewed from the polymer substrate, and the binding energy of the Si2p orbit at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is the first energy. The gas barrier film is larger than the binding energy of Si2p orbitals in the layer and smaller than the binding energy of Si2p orbitals in the second layer.

  A gas barrier film having a high gas barrier property against water vapor can be provided.

It is sectional drawing which showed an example of the gas barrier film of this invention. It is sectional drawing which showed an example of the gas barrier film of this invention. It is an example of the graph which showed the Si2p spectrum obtained by the X-ray photoelectron spectroscopy in the interface of a 1st layer, a 2nd layer, and a 1st layer and a 2nd layer. It is an example of the graph which showed the Zn2p3 / 2 spectrum obtained by the X-ray photoelectron spectroscopy in the interface of a 1st layer and a 2nd layer. It is the schematic which shows typically the winding-type sputtering chemical vapor deposition apparatus for manufacturing the gas barrier film of this invention.

[Gas barrier film]
The gas barrier film of the present invention is a gas barrier film in which a gas barrier layer is disposed on at least one surface of a polymer substrate, and the gas barrier layer comprises a first layer containing zinc oxide and silicon dioxide, and a silicon compound. And the second layer including the second layer is in contact with the polymer base material in this order, and the binding energy of the Si2p orbit at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is The gas barrier film is larger than the binding energy of Si2p orbitals in the first layer and smaller than the binding energy of Si2p orbitals in the second layer. The “first layer containing zinc oxide and silicon dioxide” may be simply abbreviated as “first layer” and the “second layer containing silicon compound” may be simply abbreviated as “second layer”.

  FIG. 1 shows a cross-sectional view of an example of the gas barrier film of the present invention. The gas barrier film of this embodiment has a gas barrier layer 2 on one side of the polymer substrate 1. In the gas barrier layer 2, a first layer 2 a containing zinc oxide and silicon dioxide and a second layer 2 b containing a silicon compound are arranged in contact with each other in this order as viewed from the polymer substrate 1. By arranging the second layer 2b containing the silicon compound in contact with the first layer 2a containing zinc oxide and silicon dioxide, defects such as pinholes and cracks on the surface of the first layer are included in the second layer. Filled with a silicon compound, the gas barrier layer 2 has a high gas barrier property.

  The reason why the gas barrier property is improved by applying the second layer containing a silicon compound in the gas barrier film of the present invention is estimated as follows (i), (ii), and (iii).

  (I) Since the second layer contains a silicon compound, the entire layer becomes amorphous and dense. Therefore, the second layer is formed on the surface of a defect having a large size such as a crack or a pinhole existing on the surface of the first layer or inside the defect. The silicon compound of the layer is efficiently filled, and the water vapor transmission is suppressed and the gas barrier property is improved as compared with the case of the first single layer.

  (Ii) Since the second layer contains silicon atoms having an atomic radius smaller than that of the zinc atoms in the first layer, defects having a size of several nm or less existing on the surface of the first layer can be efficiently filled with silicon atoms. Improves.

  (Iii) Since the zinc atoms contained in the first layer are elements having a low melting point, the second atoms filled in the atomic defects on the surface of the first layer are affected by plasma and heat during the formation of the second layer. Since silicon atoms and oxygen atoms in the layer are chemically bonded to zinc atoms and silicon atoms contained in the first layer to form a silicate bond, the atomic defects on the surface of the first layer are reduced and the order of the bonded state is improved. The voids are reduced to develop a higher gas barrier property.

  In the present invention, the Si2p orbital binding energy in the first layer refers to the binding energy at a half position in the thickness direction of the first layer. Similarly, the binding energy of the Si2p orbit in the second layer refers to the binding energy at a half position in the thickness direction of the second layer.

  The binding energy in the Si2p orbital is the binding energy of bound electrons existing in the 2p orbital of the Si atom, and is an energy value indicating the maximum detected intensity in the Si2p spectrum obtained by X-ray photoelectron spectroscopy. . That is, the change in the bonding state in the Si atom can be grasped from the change in the binding energy in the Si2p orbital.

  Further, the binding energy of the Si2p orbit at the interface between the first layer and the second layer refers to the binding energy of the Si2p orbital on the surface of the first layer. That is, as will be described later, argon ion etching is performed from the surface of the second layer toward the first layer side, and the second layer reaches the interface between the first layer and the second layer confirmed by cross-sectional observation with a transmission electron microscope. This refers to the binding energy of the Si2p orbit when the layer is removed and the surface of the first layer from which the second layer is removed is measured.

  FIG. 3 shows an example of a graph showing Si2p spectra obtained by X-ray photoelectron spectroscopy at the first layer, the second layer, and the interface between the first layer and the second layer. FIG. 3 shows a standardized Si2p spectrum obtained by X-ray photoelectron spectroscopy, with the minimum value of detection intensity being 0 and the maximum value being 1.

  In the present invention, the binding energy of the Si2p orbitals at the interface between the first layer and the second layer is larger than the binding energy of the Si2p orbitals in the first layer and smaller than the binding energy of the Si2p orbitals in the second layer. By forming the second layer on the surface layer of the first layer, it shows that a stronger bond than the first layer is formed at the interface between the first layer and the second layer. Although details are not clear, since the zinc atoms contained in the first layer are elements with a low melting point, the surface of the first layer is affected by plasma and heat during the formation of the second layer, When desorbed from the surface of the first layer and the second layer contains silicon oxide, it is chemically bonded to the silicon atoms and oxygen atoms of the second layer to form Zn—O—Si zinc silicate bonds. It is considered that a stronger bond than the first layer is formed at the interface between the first layer and the second layer. In addition, the silicon atoms and oxygen atoms in the second layer filled in the atomic defects on the surface of the first layer are chemically bonded to zinc atoms and silicon atoms having dangling bonds contained in the first layer, and Zn—O—. It is considered that a bond of Si zinc silicate was formed, and a bond stronger than the first layer was formed at the interface between the first layer and the second layer. That is, a second layer containing a silicon compound is formed on the surface of the first layer containing zinc oxide and silicon dioxide, and a zinc silicate of Zn—O—Si is formed on the surface of the first layer, thereby having dangling bonds. Zinc atoms and silicon atoms are reduced, and as a result, the binding energy of the Si2p orbitals at the interface between the first layer and the second layer is larger than that of the first layer. In addition, when the second layer includes a silicon oxide, it includes many highly ordered covalent bonds of Si—O—Si. Therefore, the interface between the first layer and the first layer and the second layer is the first layer. It becomes smaller than the binding energy of the Si2p orbital in the two layers. Due to this effect, defects on the surface of the first layer are filled with the silicon compound or silicon atom of the second layer, and a bond of zinc silicate stronger than the first layer is formed at the interface between the first layer and the second layer. Therefore, the voids are reduced due to the reduction of atomic defects on the surface of the first layer and the improvement of the ordering of the bonded state, and high gas barrier properties are exhibited. In addition, since the adhesion between the first layer and the second layer becomes stronger due to the bonding of zinc silicate at the interface between the first layer and the second layer, peeling or lowering of adhesion due to bending or external impact is caused during use. It is presumed that it will be a gas barrier film that does not easily occur and can maintain high gas barrier properties.

  When the binding energy of the Si2p orbitals at the interface between the first layer and the second layer is the same or smaller than the binding energy of the Si2p orbitals in the first layer, there are many Si atoms or defects with weak bonds on the surface of the first layer. Since there is no bond of zinc silicate stronger than that of the first layer, the effect of greatly improving the gas barrier property by stacking the second layer cannot be obtained. In addition, when the binding energy of the Si2p orbitals at the interface between the first layer and the second layer is the same as or larger than the binding energy of the Si2p orbitals in the second layer, it is in a state of being chemically bonded only by the forming elements of the second layer. Since the zinc silicate bond chemically bonded with the elements constituting the first layer and the second layer is not formed, the interface between the first layer and the second layer is peeled off or the adhesion is deteriorated by bending or external impact. The gas barrier properties may be reduced.

  Accordingly, it is preferable that the binding energy of the Si2p orbitals at the interface between the first layer and the second layer is larger than the binding energy of the Si2p orbitals in the first layer and smaller than the binding energy of the Si2p orbitals in the second layer. The binding energy of Si2p orbitals at the interface between the first layer and the second layer is preferably 0.2 eV or more larger than the binding energy of Si2p orbitals in the first layer. Further, the Si2p orbital bond energy at the interface between the first layer and the second layer is preferably larger than the Si2p orbital bond energy in the first layer in a range of 1.5 eV or less. The binding energy of Si2p orbitals at the interface between the first layer and the second layer is preferably 0.1 eV or more smaller than the binding energy of Si2p orbitals in the second layer. Further, the Si2p orbital bond energy at the interface between the first layer and the second layer is more preferably 0.7 eV or less than the Si2p orbital bond energy in the second layer. In addition, from the viewpoint of forming a strong zinc silicate bond on the surface of the first layer and improving the gas barrier property and improving the adhesion between the first layer and the second layer, the first layer and the second layer The binding energy of Si2p orbitals at the interface is preferably 102.0 eV or more and 103.8 eV or less.

  As a method for making the binding energy of the Si2p orbital at the interface between the first layer and the second layer larger than the binding energy of the Si2p orbital in the first layer and smaller than the binding energy of the Si2p orbital in the second layer, First, during the formation of the first layer, the polymer substrate is heated to 50 ° C. or higher, and the layer containing zinc oxide and silicon dioxide is formed with a dense structure with few atomic defects on the surface of the first layer. preferable. Next, the polymer base material is heated to 50 ° C. or higher during the second layer deposition, and further, the first layer surface is processed with high energy using plasma, electron beam, ion beam, etc. As a result, zinc atoms on the surface of the first layer are desorbed and chemically bonded to silicon atoms and oxygen atoms of the second layer, so that zinc silicate such as Zn—O—Si is formed at the interface between the first layer and the second layer. A method of forming the second layer so as to form a bond of is preferable.

  In the gas barrier film, it is preferable that the half width of the binding energy peak of the Zn2p3 / 2 orbit at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is 2.5 eV or more. An example of a graph showing a Zn2p3 / 2 spectrum obtained by X-ray photoelectron spectroscopy at the interface between the first layer and the second layer is shown in FIG. Here, the half-value width of the binding energy peak of the Zn2p3 / 2 orbit is the intensity when the minimum value of the detected intensity is normalized to 0 and the maximum value is 1 in the Zn2p3 / 2 spectrum obtained by X-ray photoelectron spectroscopy. The spectral width at 0.5 is indicated by the energy value.

  When the half width of the binding energy peak of Zn2p3 / 2 orbit at the interface between the first layer and the second layer is 2.5 eV or more, the interface between the first layer and the second layer is stronger than the first layer. A zinc silicate bond is formed and densified, and high gas barrier properties are obtained, which is preferable. When the half width of the binding energy peak of the Zn2p3 / 2 orbit at the interface between the first layer and the second layer is smaller than 2.5 eV, the interface between the first layer and the second layer is stronger than the first layer. Since the zinc silicate bond is not formed, high gas barrier properties may not be exhibited. Therefore, the half width of the binding energy peak of the Zn2p3 / 2 orbit at the interface between the first layer and the second layer is preferably 2.5 eV or more, and more preferably 2.7 eV or more. The half width is preferably 4.0 eV or less, and more preferably 3.5 eV or less. In addition, from the viewpoint of forming a strong zinc silicate bond on the surface of the first layer and obtaining an effect of improving the gas barrier property, the binding energy of the Zn2p3 / 2 orbit at the interface between the first layer and the second layer is 1, It is preferable that it is 020.0 eV or more and 1,024.0 eV or less.

  The binding energy of the Zn2p3 / 2 orbit at the interface between the first layer and the second layer is confirmed by cross-sectional observation with a transmission electron microscope from the surface of the second layer toward the first layer. The second layer is removed by argon etching up to the interface with the layer, and the surface of the first layer from which the second layer has been removed can be obtained by X-ray photoelectron spectroscopy.

[Polymer substrate]
The polymer substrate used in the present invention preferably has a film form from the viewpoint of ensuring flexibility. As a structure of a film, a single layer film may be sufficient and the film formed by the coextrusion method of two or more layers may be sufficient. As the type of film, a film stretched in a uniaxial direction or a biaxial direction may be used.

  The material of the polymer substrate is not particularly limited, but is preferably an organic polymer as a main constituent. Examples of the organic polymer that can be suitably used in the present invention include crystalline polyolefins such as polyethylene and polypropylene; amorphous cyclic polyolefins having a cyclic structure; polyesters such as polyethylene terephthalate and polyethylene naphthalate; polyamides, polycarbonates, Examples include polystyrene, polyvinyl alcohol, saponified ethylene vinyl acetate copolymer, various polymers such as polyacrylonitrile and polyacetal. Among these, amorphous cyclic polyolefin or polyethylene terephthalate which is excellent in transparency, versatility and mechanical properties is preferable. The organic polymer may be a homopolymer or a copolymer. Further, only one type of organic polymer may be used, or a plurality of types may be blended.

  In order to improve adhesion and smoothness, the surface of the polymer substrate on which the gas barrier layer is formed is treated with corona treatment, plasma treatment, ultraviolet treatment, ion bombardment treatment, solvent treatment, organic or inorganic matter, or a mixture thereof. A pretreatment such as an undercoat layer forming treatment may be applied. In addition, a coating layer of an organic material, an inorganic material, or a mixture thereof may be laminated on the side opposite to the side on which the gas barrier layer is formed for the purpose of improving the slipping property at the time of winding the film.

  The thickness of the polymer substrate is not particularly limited, but is preferably 500 μm or less from the viewpoint of ensuring flexibility, and is preferably 5 μm or more from the viewpoint of ensuring strength against tension or impact. Furthermore, the thickness of the polymer substrate is more preferably 10 μm or more and 200 μm or less because of the ease of film processing and handling.

[First layer containing zinc oxide and silicon dioxide]
The gas barrier film of the present invention can exhibit high gas barrier properties when the gas barrier layer has the first layer containing zinc oxide and silicon dioxide. The reason why the gas barrier property is improved by applying the first layer containing zinc oxide and silicon dioxide is that the crystalline zinc oxide component and the vitreous silicon dioxide component coexist to produce microcrystals. It is presumed that the crystal growth of zinc oxide, which is easy, is suppressed and the particle diameter of zinc oxide is reduced, so that the layer is densified and the permeation of water vapor is suppressed. In addition, the layer containing zinc oxide and silicon dioxide is superior in flexibility to a thin film formed of an oxide composed of only one metal element such as aluminum oxide, titanium oxide, zirconium oxide, etc. It is considered that cracks are less likely to occur with respect to the stress of and that it is possible to suppress a decrease in gas barrier properties.

  If the first layer contains zinc oxide and silicon dioxide, aluminum (Al), gallium (Ga), titanium (Ti), zirconium (Zr), tin (Sn), indium (In), niobium (Nb) ), Molybdenum (Mo), and tantalum (Ta), and may further include at least one element selected from the group consisting of tantalum (Ta). Further, oxides, nitrides, sulfides, or mixtures of these elements may be included. For example, a layer made of zinc oxide, silicon dioxide, and aluminum oxide is preferably used as the first layer because high gas barrier properties can be obtained.

  The thickness of the first layer is preferably 10 nm or more and 1,000 nm or less from the viewpoint of gas barrier properties. When the thickness of the layer is less than 10 nm, there may be a portion where the gas barrier property cannot be sufficiently secured, and the gas barrier property may vary in the polymer substrate surface. Further, if the thickness of the layer is greater than 1,000 nm, the stress remaining in the layer increases, so that the first layer is likely to crack due to bending or external impact, and the gas barrier properties are reduced with use. There is a case. The thickness of the first layer is more preferably 100 nm or more and 500 nm or less from the viewpoint of ensuring flexibility. The thickness of the first layer can be measured by cross-sectional observation with a transmission electron microscope (TEM).

  The center plane average roughness SRa of the first layer is preferably 10 nm or less. When SRa is larger than 10 nm, the uneven shape on the surface of the first layer becomes large, and a gap is formed between the sputtered particles to be laminated. Therefore, the film quality is difficult to be dense, and even if the film thickness is increased, the gas barrier property is improved May be difficult to obtain. Also, when SRa is larger than 10 nm, the film quality of the second layer laminated on the first layer is not uniform, so that the Si2p orbital at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy The bond energy cannot be made larger than the bond energy of the Si2p orbitals in the first layer and less than the bond energy of the Si2p orbitals in the second layer, and the gas barrier property may be lowered. Accordingly, the SRa of the first layer is preferably 10 nm or less, more preferably 7 nm or less. The SRa of the first layer can be measured using a three-dimensional surface roughness measuring machine.

  The method for forming the first layer is not particularly limited, and the first layer can be formed by a vacuum deposition method, a sputtering method, an ion plating method, or the like. For example, by using a mixed sintered material that matches the composition of the target layer with the composition ratio of zinc oxide, silicon dioxide and other components as required, by vacuum evaporation, sputtering, ion plating, etc. A first layer can be formed on the polymer substrate. Alternatively, the first layer can be formed by simultaneously forming films of zinc oxide, silicon dioxide, and other simple materials from different vapor deposition sources or sputter electrodes, and mixing them to have a desired composition. Among these methods, a sputtering method using a mixed sintered material is more preferable from the viewpoint of composition reproducibility and simplicity of the formed layer. In addition, by forming the first layer in a state where the polymer substrate is heated to 50 ° C. or higher, the surface of the first layer becomes a flat surface having a dense structure with few atomic defects and a small surface roughness. Thereby, the second layer formed on the first layer becomes uniform, and the first layer and the second layer are easily bonded to each other, so that the gas barrier property can be further improved, which is preferable. Therefore, a method of forming the first layer by sputtering in a state where the polymer substrate is heated to 50 ° C. or higher is particularly preferable.

[Zinc oxide-silicon dioxide-aluminum oxide layer]
Details of the layer made of zinc oxide, silicon dioxide, and aluminum oxide that are suitably used as the first layer will be described. In addition, the “layer consisting of zinc oxide, silicon dioxide and aluminum oxide” may be abbreviated as “zinc oxide-silicon dioxide-aluminum oxide layer” or “ZnO—SiO ₂ —Al ₂ O ₃ layer”.

Silicon (SiO ₂₎ dioxide, the generation time of the conditions, which composition ratio of silicon and oxygen is offset slightly from left composition formula (SiO~SiO ₂₎ although it is possible to produce, in which case silicon dioxide or SiO also It shall be written as ₂ . Regarding the deviation from the chemical formula of the composition ratio of the metal element and oxygen, the same treatment is applied to zinc oxide and aluminum oxide, respectively, regardless of the deviation of the composition ratio depending on the conditions at the time of formation, respectively, zinc oxide or ZnO. In this case, it is expressed as aluminum oxide or Al ₂ O ₃ .

  The reason why the gas barrier property is improved by applying the zinc oxide-silicon dioxide-aluminum oxide layer as the first layer is that the layer containing zinc oxide and silicon dioxide further coexists with aluminum oxide, so Since crystal growth can be further suppressed as compared with the case where only silicon is allowed to coexist, it is considered that a decrease in gas barrier properties due to generation of cracks can be suppressed.

  The composition of the zinc oxide-silicon dioxide-aluminum oxide layer can be obtained by measuring by X-ray photoelectron spectroscopy (XPS method) as described later. Here, the composition of the first layer in the present invention is represented by the atomic concentration ratio of each element measured by the XPS method at a position of 1/2 of the thickness direction of the first layer. The thickness of the first layer is the thickness obtained by cross-sectional observation with a transmission electron microscope (TEM) as described above. The first layer has a zinc (Zn) atom concentration of 10 to 35 atom%, a silicon (Si) atom concentration of 7 to 25 atom%, an aluminum (Al) atom concentration of 0.5 to 5 atom%, oxygen, as measured by XPS method. (O) The atomic concentration is preferably 45 to 70 atom%.

  When the zinc (Zn) atom concentration is higher than 35 atom% or the silicon (Si) atom concentration is lower than 7 atom%, silicon dioxide and / or aluminum oxide that suppresses the crystal growth of zinc oxide is insufficient. Defects may increase and sufficient gas barrier properties may not be obtained. When the zinc (Zn) atom concentration is less than 10 atom% or the silicon (Si) atom concentration is more than 25 atom%, the amorphous component of silicon dioxide inside the layer may increase and the flexibility of the layer may decrease. is there. Also, when the aluminum (Al) atomic concentration is higher than 5 atom%, the affinity between zinc oxide and silicon dioxide becomes excessively high, so that the pencil hardness of the film increases, and cracks are likely to occur due to heat and external stress. There is a case. When the aluminum (Al) atomic concentration is less than 0.5 atom%, the affinity between zinc oxide and silicon dioxide decreases, and the bonding force between the particles forming the layer cannot be improved, so that the flexibility may decrease. In addition, when the oxygen (O) atom concentration is higher than 70 atom%, the amount of defects in the first layer increases, so that a desired gas barrier property may not be obtained. When the oxygen (O) atom concentration is less than 45 atom%, the oxidation state of zinc, silicon and aluminum becomes insufficient, the crystal growth cannot be suppressed, and the particle diameter becomes large, so that the gas barrier property may be lowered. From this point of view, the zinc (Zn) atom concentration is 15 to 32 atom%, the silicon (Si) atom concentration is 10 to 20 atom%, the aluminum (Al) atom concentration is 1 to 3 atom%, and the oxygen (O) atom concentration is 50 to 64 atom%. % Is more preferable.

  The components contained in the zinc oxide-silicon dioxide-aluminum oxide layer are not particularly limited as long as zinc oxide, silicon dioxide, and aluminum oxide are in the above composition and are main components. For example, titanium (Ti), zirconium (Zr) , Tin (Sn), indium (In), niobium (Nb), molybdenum (Mo), tantalum (Ta), palladium (Pd), and other metal oxides may be further included. Here, the main component means 50% by mass or more of the composition of the first layer, preferably 60% by mass or more, and more preferably 80% by mass or more.

  Since the composition of the first layer is formed with the same composition as the mixed sintered material used at the time of forming the layer, the first layer can be obtained by using a mixed sintered material having a composition that matches the composition of the target layer. It is possible to adjust the composition.

  The composition of the first layer can be known by measuring the composition ratio of zinc, silicon, aluminum, oxygen and other contained elements using the XPS method. In the XPS method, elemental information can be obtained from the binding energy value of the bound electrons obtained by detecting photoelectrons emitted from the surface when the sample surface is irradiated with soft X-rays in an ultra-high vacuum. Furthermore, each detection element can be quantified from the peak area ratio of the binding energy.

  When an inorganic layer or a resin layer is laminated on the first layer, the thickness of the inorganic layer or the resin layer is measured by cross-sectional observation with a transmission electron microscope, and the inorganic layer or the resin layer is measured by ion etching or chemical treatment. After removing the resin layer, it can be further removed by argon ion etching to a position where the thickness of the first layer becomes ½ and analyzed by X-ray photoelectron spectroscopy.

[Second layer containing silicon compound]
Next, the details of the second layer containing a silicon compound will be described. The second layer in the present invention is a layer containing a silicon compound, and the silicon compound may contain silicon oxide, silicon nitride, silicon carbide, silicon oxynitride, or a mixture thereof. In particular, the silicon compound preferably contains at least one selected from the group consisting of silicon dioxide, silicon carbide, silicon nitride, and silicon oxynitride.

It is preferable that the content rate of the silicon compound in a 2nd layer is 50 mass% or more, More preferably, it is 60 mass% or more, More preferably, it is 80 mass% or more. In addition, the silicon compound in the present invention is treated as a compound having a composition formula in which the composition ratio of each element whose component is specified by X-ray photoelectron spectroscopy, ICP emission spectroscopy, Rutherford backscattering method or the like is represented by an integer. For example, silicon dioxide (SiO _2), by the generation time of the condition, those slightly deviated from the composition ratio of silicon and oxygen on the left formula (SiO~SiO ₂₎ although it is possible to produce, even in such a case The mass content is calculated as SiO ₂ .

  The composition of the second layer containing a silicon compound can be measured by X-ray photoelectron spectroscopy. Here, the composition of the second layer in the present invention is the atomic concentration ratio of each element measured by the XPS method at the position where the thickness of the second layer becomes 1/2.

  When an inorganic layer or a resin layer is laminated on the second layer, after removing the thickness of the inorganic layer or the resin layer measured by cross-sectional observation with a transmission electron microscope by ion etching or chemical treatment, It can be removed by argon ion etching until the thickness of the second layer becomes 1/2 and analyzed by X-ray photoelectron spectroscopy.

  In the case where the second layer is a layer containing silicon oxide, the composition is such that the silicon (Si) atom concentration measured by X-ray photoelectron spectroscopy is 25 to 45 atom%, and the oxygen (O) atom concentration is 55 to 75 atom%. It is preferable that When the silicon (Si) atom concentration is lower than 25 atom% or the oxygen atom concentration is higher than 75 atom%, oxygen atoms bonded to silicon atoms are excessively increased, resulting in an increase in voids and defects inside the layer and a decrease in gas barrier properties. There is a case. In addition, when the silicon (Si) atom concentration is higher than 45 atom% or the oxygen (O) atom concentration is lower than 55 atom%, the film becomes excessively dense, which may cause large curl or decrease in flexibility. As a result, cracks are likely to occur due to heat or external stress, and the gas barrier properties may be reduced. From this viewpoint, the second layer preferably has a silicon (Si) atom concentration of 28 to 40 atom% and an oxygen (O) atom concentration of 60 to 72 atom%, and further has a silicon (Si) atom concentration of 30 to 30. More preferably, it is 35 atom% and the oxygen (O) atom concentration is 65 to 70 atom%.

  The component contained in the second layer is not particularly limited as long as the silicon (Si) atom concentration and the oxygen (O) atom concentration are within the above-mentioned composition. For example, zinc (Zn), aluminum (Al), titanium (Ti) Further, a metal oxide formed from zirconium (Zr), tin (Sn), indium (In), niobium (Nb), molybdenum (Mo), tantalum (Ta), palladium (Pd), or the like may be included.

  The thickness of the second layer is preferably 10 nm or more, and more preferably 100 nm or more. If the thickness of the layer is thinner than 10 nm, the gas barrier properties may vary depending on the location. The thickness of the second layer is preferably 1,000 nm or less, and more preferably 500 nm or less. If the thickness of the layer is greater than 1,000 nm, the stress remaining in the layer increases, so that the second layer is likely to crack due to bending or external impact, and the gas barrier properties may decrease with use. is there.

  The method for forming the second layer is not particularly limited. For example, the second layer can be formed by a film forming method such as a vacuum evaporation method, a sputtering method, a chemical vapor deposition method (abbreviated as a CVD method), or the like. Cracks, pinholes, atomic defects, etc. existing on the surface of the first layer are efficiently filled with atoms that form the second layer, and the Si2p orbital binding energy at the interface between the first layer and the second layer is In order to make it larger than the binding energy of the Si2p orbital in the first layer and smaller than the binding energy of the Si2p orbital in the second layer, the first energy is high so that atoms constituting the second layer are activated on the surface of the first layer. A method of forming the second layer while treating the layer surface is preferred.

  For example, when using a vacuum deposition method, a plasma of a reactive gas such as oxygen gas or carbon dioxide gas is generated during film formation in a state where the polymer substrate is heated to 50 ° C. or more, and the plasma is further accelerated to generate a beam. An ion beam assisted deposition method in which the second layer is formed while treating the surface of the first layer is preferable.

  When the sputtering method is used, in a state where the polymer base material is heated to 50 ° C. or higher, a beam of reactive gas such as oxygen gas or carbon dioxide gas is generated and accelerated separately from the plasma for sputtering the target material. An ion beam assisted sputtering method is preferred, in which the second layer is formed while treating the surface of the first layer.

  When the CVD method is used, a high-density plasma of a reactive gas such as oxygen gas or carbon dioxide gas is generated by an induction coil in a state where the polymer substrate is heated to 50 ° C. or higher, and the surface of the first layer by the plasma is generated. A plasma CVD method using an inductively coupled CVD electrode that simultaneously performs the treatment and the formation of the second layer by the polymerization reaction of a monomer gas of a silicon-based organic compound is preferable.

  Among these methods, an inductively coupled CVD electrode capable of efficiently filling the defects in the surface of the first layer with atoms contained in the second layer and processing the surface of the first layer in a large area and uniformly is used. The plasma CVD method used is more preferable.

  The silicon-based organic compound used in the CVD method is a compound containing silicon inside the molecule. For example, silane, methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, ethylsilane, diethylsilane, triethylsilane, tetraethyl Silane, propoxysilane, dipropoxysilane, tripropoxysilane, tetrapropoxysilane, dimethyldisiloxane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetramethyldisiloxane, hexamethyldisiloxane, tetramethoxysilane, tetraethoxysilane Tetrapropoxysilane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, undecamethylcyclohexasiloxane Hexane, dimethyl disilazane, trimethyl disilazane, tetramethyl disilazane, hexamethyl disilazane, hexamethylcyclotrisilazane, octamethylcyclotetrasilazane, decamethylcyclopentasiloxane silazane, such undecapeptide methyl cyclohexasilane La disilazane and the like. Among these, hexamethyldisiloxane, tetraethoxysilane, and hexamethyldisilazane are preferable from the viewpoint of handling.

[Undercoat layer]
The gas barrier film includes an undercoat including a structure obtained by crosslinking a polyurethane compound having an aromatic ring structure between the polymer base material and the first layer in order to improve gas barrier properties and flex resistance. A layer is preferably provided. An example of the gas barrier film of this embodiment is shown in FIG. By having the undercoat layer 3, even if there are protrusions or scratches on the surface of the polymer substrate 1, it can be flattened, and the gas barrier layer grows evenly without unevenness. It becomes a gas barrier film. In addition, when the difference in thermal dimensional stability between the polymer base material and the first layer is large, it is preferable to provide an undercoat layer because a decrease in gas barrier properties and flex resistance can be prevented.

  The undercoat layer is selected from an ethylenically unsaturated compound, a photopolymerization initiator, an organic silicon compound and an inorganic silicon compound in addition to a polyurethane compound having an aromatic ring structure from the viewpoint of thermal dimensional stability and flex resistance. More preferably, it contains a structure obtained by crosslinking the above compound. Hereinafter, these polyurethane compounds, ethylenically unsaturated compounds, photopolymerization initiators, organic silicon compounds, and inorganic silicon compounds, excluding the solvent, are referred to as polymerizable components.

  A polyurethane compound having an aromatic ring structure is a compound having an aromatic ring and a urethane bond in the main chain or side chain. For example, it can be obtained by polymerizing an epoxy (meth) acrylate having a hydroxyl group and an aromatic ring in the molecule, a diol compound, and a diisocyanate compound.

  As epoxy (meth) acrylate having a hydroxyl group and an aromatic ring in the molecule, diepoxy compounds of aromatic glycols such as bisphenol A type, hydrogenated bisphenol A type, bisphenol F type, hydrogenated bisphenol F type, resorcin, hydroquinone, etc. And a (meth) acrylic acid derivative.

  Examples of the diol compound include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 2,4-dimethyl-2-ethylhexane-1,3-diol, neopentyl Glycol, 2-ethyl-2-butyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 1,2-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2,4, 4-tetramethyl-1,3-cyclobutanediol, 4,4′-thiodiph Diol, bisphenol A, 4,4′-methylenediphenol, 4,4 ′-(2-norbornylidene) diphenol, 4,4′-dihydroxybiphenol, o-, m-, and p-dihydroxybenzene, 4,4 '-Isopropylidenephenol, 4,4'-isopropylidenebindiol, cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, bisphenol A, and the like can be used. These can be used alone or in combination of two or more.

  Examples of the diisocyanate compound include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-diphenylmethane diisocyanate, and 4,4-diphenylmethane diisocyanate. Aromatic diisocyanates such as ethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate; Aliphores such as isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, methylcyclohexylene diisocyanate System an isocyanate compound; xylene diisocyanate, aromatic aliphatic isocyanate compounds such as tetramethyl xylylene diisocyanate. These can be used alone or in combination of two or more.

  The weight average molecular weight (Mw) of the polyurethane compound having an aromatic ring structure is preferably 5,000 to 100,000. A weight average molecular weight (Mw) of 5,000 to 100,000 is preferable because the resulting cured film has excellent thermal dimensional stability and flex resistance. In addition, the weight average molecular weight (Mw) in this invention is the value measured using the gel permeation chromatography method and converted with standard polystyrene.

  Examples of the ethylenically unsaturated compound include di (meth) acrylates such as 1,4-butanediol di (meth) acrylate and 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and penta Multifunctional (meth) acrylates such as erythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A type epoxy di (meth) acrylate And epoxy acrylates such as bisphenol F type epoxy di (meth) acrylate and bisphenol S type epoxy di (meth) acrylate. Among these, polyfunctional (meth) acrylates excellent in thermal dimensional stability and surface protection performance are preferable. Moreover, these may be used independently and may mix and use 2 or more types.

  The content of the ethylenically unsaturated compound is not particularly limited, but from the viewpoint of thermal dimensional stability and surface protection performance, the total amount of the polymerizable components is preferably in the range of 5 to 90% by mass, A range of 10 to 80% by mass is more preferable.

  The photopolymerization initiator is not particularly limited as long as the gas barrier property and the bending resistance of the gas barrier film can be maintained. Examples of the photopolymerization initiator that can be suitably used include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexylphenyl-ketone, 2-hydroxy-2-methyl-1 -Phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [ 4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, phenylglyoxylic acid methyl ester, 2-methyl-1- (4-methylthiophenyl)- 2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2- ( Alkylphenone photopolymerization initiators such as methylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone; 2,4,6-trimethylbenzoyl -Acylphosphine oxide photopolymerization initiators such as diphenyl-phosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; bis (η5-2,4-cyclopentadien-1-yl) -bis ( Titanocene photopolymerization initiators such as 2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium; 1,2-octanedione, 1- [4- (phenylthio) -2- (0 -Benzoyloxime)] and other photopolymerization initiators having an oxime ester structure.

  Among these, from the viewpoint of curability and surface protection performance, 1-hydroxy-cyclohexylphenyl-ketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2,4,6 -Photopolymerization initiators selected from trimethylbenzoyl-diphenyl-phosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide are preferred. These may be used singly or in combination of two or more.

  Although content of a photoinitiator is not specifically limited, From a viewpoint of sclerosis | hardenability and surface protection performance, it is preferable that it is the range of 0.01-10 mass% in 100 mass% of total amounts of a polymeric component, The range of 0.1 to 5% by mass is more preferable.

  Examples of the organosilicon compound include vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltri Methoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxy Silane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3 Aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-isocyanate propyl triethoxysilane, and the like.

  Among these, from the viewpoint of curability and polymerization activity by active energy ray irradiation, selected from the group consisting of 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane. At least one organosilicon compound is preferred. These may be used singly or in combination of two or more.

  The content of the organosilicon compound is not particularly limited, but is preferably in the range of 0.01 to 10% by mass in 100% by mass of the total amount of polymerizable components from the viewpoint of curability and surface protection performance. A range of 1 to 5% by mass is more preferable.

As the inorganic silicon compound, silica particles are preferable from the viewpoint of surface protection performance and transparency. The primary particle diameter of the silica particles is preferably in the range of 1 to 300 nm, more preferably in the range of 5 to 80 nm. In addition, the primary particle diameter here is the specific surface area s obtained by the gas adsorption method as shown in the following formula (1).
d = 6 / ρs (1)
ρ: The particle diameter d obtained by applying to the density.

  The thickness of the undercoat layer is preferably from 200 nm to 4,000 nm, more preferably from 300 nm to 2,000 nm, still more preferably from 500 nm to 1,000 nm. If the thickness of the undercoat layer is less than 200 nm, the adverse effects of defects such as protrusions and scratches present on the polymer substrate may not be suppressed. When the thickness of the undercoat layer is greater than 4,000 nm, the smoothness of the undercoat layer is reduced, and the uneven shape of the surface of the first layer laminated on the undercoat layer is increased, and gaps are formed between the sputtered particles to be laminated. Therefore, the film quality is less likely to be dense, and the effect of improving gas barrier properties may be difficult to obtain. Here, the thickness of the undercoat layer can be measured from a cross-sectional observation image by a transmission electron microscope (TEM).

  The center surface average roughness SRa of the undercoat layer is preferably 10 nm or less. When SRa is 10 nm or less, it is easy to form a homogeneous first layer on the undercoat layer, and it is preferable because repeated reproducibility of gas barrier properties is improved. When the SRa on the surface of the undercoat layer is greater than 10 nm, the uneven shape on the surface of the first layer on the undercoat layer also increases, and gaps are formed between the stacked sputtered particles, making it difficult for the film quality to become dense and gas barrier properties. It may be difficult to obtain the improvement effect. In addition, since cracks due to stress concentration are likely to occur in portions where there are many irregularities, it may cause a reduction in the reproducibility of gas barrier properties. Therefore, the SRa of the undercoat layer is preferably 10 nm or less, more preferably 7 nm or less.

  SRa of the undercoat layer can be measured using a three-dimensional surface roughness measuring machine.

  When an undercoat layer is applied to a gas barrier film, as a coating means for forming the undercoat layer, first, a paint containing a polyurethane compound having an aromatic ring structure on a polymer substrate is dried. It is preferable to adjust the solid content concentration so that the thickness becomes a desired thickness, and apply by, for example, reverse coating method, gravure coating method, rod coating method, bar coating method, die coating method, spray coating method, spin coating method and the like. Moreover, it is preferable to dilute the coating material containing the polyurethane compound which has an aromatic ring structure using an organic solvent from a viewpoint of coating suitability.

  Specifically, using a hydrocarbon solvent such as xylene, toluene, methylcyclohexane, pentane, or hexane, or an ether solvent such as dibutyl ether, ethylbutyl ether, or tetrahydrofuran, the solid content concentration is 10% by mass or less. It is preferable to use a diluted paint. These solvents may be used alone or in combination of two or more. Moreover, various additives can be mix | blended with the coating material which forms an undercoat layer as needed. For example, a catalyst, an antioxidant, a light stabilizer, an ultraviolet absorber, a surfactant, a leveling agent, an antistatic agent and the like can be used.

  Subsequently, it is preferable to dry the coating film after application | coating and to remove a dilution solvent. Here, there is no restriction | limiting in particular as a heat source used for drying, Arbitrary heat sources, such as a steam heater, an electric heater, and an infrared heater, can be used. In order to improve gas barrier properties, the heating temperature is preferably 50 to 150 ° C. The heat treatment time is preferably several seconds to 1 hour. Furthermore, the temperature may be constant during the heat treatment, or the temperature may be gradually changed. Moreover, you may heat-process, adjusting humidity in the range of 20 to 90% RH by relative humidity during a drying process. The heat treatment may be performed in the air or while enclosing an inert gas.

  Next, it is preferable to form an undercoat layer by subjecting the coating film containing a polyurethane compound having an aromatic ring structure after drying to an active energy ray irradiation treatment to crosslink the coating film.

  The active energy ray applied in such a case is not particularly limited as long as the undercoat layer can be cured, but it is preferable to use ultraviolet rays from the viewpoint of versatility and efficiency. As the ultraviolet ray generation source, a known source such as a high pressure mercury lamp metal halide lamp, a microwave type electrodeless lamp, a low pressure mercury lamp, a xenon lamp or the like can be used. Moreover, it is preferable to perform active energy ray processing in inert gas atmosphere, such as nitrogen and argon, from a viewpoint of hardening efficiency. The ultraviolet treatment may be performed under atmospheric pressure or reduced pressure, but it is preferable to perform ultraviolet treatment under atmospheric pressure from the viewpoint of versatility and production efficiency. The oxygen concentration during the ultraviolet treatment is preferably 1.0% or less, more preferably 0.5% or less, from the viewpoint of controlling the degree of crosslinking of the undercoat layer. The relative humidity may be arbitrary.

Preferably the integrated light quantity of ultraviolet irradiation is ^{0.1~1.0J / cm 2, 0.2~0.6J / cm} 2 is more preferable. It is preferable that the integrated light amount is 0.1 J / cm ² or more because a desired degree of crosslinking of the undercoat layer can be obtained. Moreover, it is preferable if the integrated light quantity is 1.0 J / cm ² or less because damage to the polymer substrate can be reduced.

[Other layers]
On the outermost surface of the gas barrier film of the present invention, a hard coat layer may be formed for the purpose of improving scratch resistance as long as the gas barrier property does not deteriorate, or a film made of an organic polymer compound is laminated. May be. The outermost surface here refers to the surface of the second layer that is not in contact with the first layer.

[Usage]
Since the gas barrier film of the present invention has a high gas barrier property, it can be used in various electronic devices. For example, it can be suitably used for an electronic device such as a back sheet of a solar cell or a flexible circuit board. Moreover, it can utilize suitably for a packaging film of foodstuffs, an electronic component, etc. besides an electronic device taking advantage of high gas barrier property.

  Hereinafter, the present invention will be specifically described based on examples. However, the present invention is not limited to the following examples.

[Evaluation method]
First, an evaluation method in each example and comparative example will be described. The number of evaluation n was n = 5 and the average value was obtained unless otherwise specified.

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

(2) Center plane average roughness SRa
Using a three-dimensional surface roughness measuring machine (manufactured by Kosaka Laboratory), the surface of each layer was measured under the following conditions.
System: Three-dimensional surface roughness analysis system “i-Face model TDA31”
X-axis measurement length / pitch: 500 μm / 1.0 μm
Y-axis measurement length / pitch: 400 μm / 5.0 μm
Measurement speed: 0.1 mm / s
Measurement environment: temperature 23 ° C., relative humidity 65%, in air.

(3) Water vapor permeability (g / (m ² · 24 hr · atm))
By the calcium corrosion method described in Japanese Patent No. 4407466, the water vapor permeability was measured in an atmosphere at a temperature of 40 ° C. and a humidity of 90% RH. The number of samples for measuring the water vapor transmission rate is 2 samples per level, the number of measurement is 5 times for each sample, and the average value of the obtained 10 points is the water vapor transmission rate (g / (m ² · 24 hr · atm) ).

(4) Composition and Si2p orbital binding energy, half width of Zn2p3 / 2 orbital binding energy peak Composition analysis of first and second layers, Si2p orbital binding energy, and Zn2p3 / 2 orbital half-value width Was performed by X-ray photoelectron spectroscopy (XPS method). The layers were removed from the surface layer by argon ion etching until the thickness of each layer became 1/2, and the measurement was performed under the following conditions. Further, the Si2p orbital binding energy and the Zn2p3 / 2 orbital half-value width at the interface between the first layer and the second layer are described in (1) from the surface of the second layer toward the first layer. The second layer is removed by argon etching up to the interface between the first layer and the second layer, which is confirmed by cross-sectional observation using a transmission electron microscope, and the surface of the first layer from which the second layer has been removed is X-ray photoelectron. It was measured under the following conditions by spectroscopic method (XPS method).
Device: Quantera SXM (PHI)
Excitation X-ray: monochromatic Al Kα1,2 line (1486.6 eV)
X-ray diameter: 100 μm
Photoelectron escape angle (inclination of detector relative to sample surface): 45 °
Ion etching: Ar ⁺ ion 2 kV
Raster size: 2 mm x 2 mm.

(5) Total light transmittance Based on JIS K7361: 1997, it measured using the turbidimeter NDH2000 (made by Nippon Denshoku Industries Co., Ltd.). The measurement was performed on three films cut into a size of 50 mm in length and 50 mm in width, the number of measurements was 5 times for each sample, and the average value of 15 times in total was the total light transmittance.

(6) Haze Based on JIS K7136: 2000, the haze was measured using a turbidimeter NDH2000 (manufactured by Nippon Denshoku Industries Co., Ltd.). The measurement was performed on three films cut into a size of 50 mm in length and 50 mm in width, the number of measurements was 5 times for each sample, and the average value of 15 measurements in total was taken as the haze value.

Example 1
(Formation of the first layer)
As the polymer substrate 1, a polyethylene terephthalate film (“Lumirror” (registered trademark) U48 manufactured by Toray Industries, Inc.) having a thickness of 50 μm was used.

A sputtering target, which is a mixed sintered material formed of zinc oxide, silicon dioxide, and aluminum oxide, is used by using a winding type sputtering / chemical vapor deposition apparatus 4 (hereinafter abbreviated as sputtering / CVD apparatus) shown in FIG. Sputtering with argon gas and oxygen gas is performed on the sputtering electrode 11, and a ZnO—SiO ₂ —Al ₂ O ₃ layer is formed as a first layer on the surface of the polymer substrate 1 to a film thickness of 150 nm. Provided.

  The specific operation is as follows. First, a sputter target sintered at a composition mass ratio of zinc oxide / silicon dioxide / aluminum oxide of 77/20/3 was placed on the sputter electrode 11 of the sputter / CVD apparatus 4. In the winding chamber 5 of the sputtering / CVD apparatus 4, the winding roll 6 was set so that the surface on the side where the first layer of the polymer substrate 1 is provided faces the sputtering electrode 11.

Next, the polymer substrate 1 was unwound from the unwinding roll 6 and passed through the main drum 10 heated to a temperature of 100 ° C. via the guide rolls 7, 8, 9. Argon gas and oxygen gas are introduced into the take-up chamber 5 at a partial pressure of oxygen gas of 10% so that the degree of vacuum is 2 × 10 ⁻¹ Pa, and input power of 3,500 W is applied to the sputter electrode 11 by a DC pulse power supply. Then, argon / oxygen gas plasma was generated, and a first layer composed of a ZnO—SiO ₂ —Al ₂ O ₃ layer was formed on the surface of the polymer substrate 1 by sputtering. The thickness of the 1st layer was adjusted with the film conveyance speed. The film on which the first layer was formed was wound on a winding roll 15 via guide rolls 12, 13, and 14.

  The composition of the first layer was such that the Zn atom concentration was 27.0 atom%, the Si atom concentration was 13.6 atom%, the Al atom concentration was 1.9 atom%, and the O atom concentration was 57.5 atom%. A test piece having a length of 100 mm and a width of 100 mm was cut out from the film on which the first layer was formed, and the center plane average roughness SRa of the surface of the first layer was evaluated. The results are shown in Table 1.

(Formation of the second layer)
Chemical vapor deposition using hexamethyldisilazane as a raw material on the first layer of the film on which the first layer obtained by the above process is formed using the sputtering / CVD apparatus having the structure shown in FIG. Hereinafter, the abbreviated CVD) was performed, and a SiO ₂ layer was provided as a _second layer so as to have a thickness of 100 nm.

The specific operation is as follows. The polymer base material 1 on which the first layer is formed is set on the unwinding roll 6 in the winding chamber 5 of the sputtering / CVD apparatus 4, unwinding, and passing through the guide rolls 7, 8, 9, the temperature It passed through the main drum 10 heated to 100 ° C. Oxygen gas 45 sccm and hexamethyldisilazane 5 sccm are introduced into the winding chamber 5 so that the degree of vacuum is 2 × 10 ⁻¹ Pa, and an applied power of 3,000 W is applied from the high frequency power source to the induction coil 17 of the CVD electrode 16. Then, plasma was generated and a second layer was formed on the first layer of the polymer substrate 1 by CVD. The film on which the second layer was formed was wound around the winding roll 15 via the guide rolls 12, 13, and 14 to obtain a gas barrier film.

  The composition of the second layer was that the Si atom concentration was 33.5 atom% and the O atom concentration was 66.5 atom%.

  A test piece having a length of 100 mm and a width of 140 mm was cut out from the obtained gas barrier film and evaluated for the binding energy of the Si2p orbital, the half width of the binding energy peak of the Zn2p3 / 2 orbital, the water vapor transmission rate, the total light transmittance, and the haze. did. The results are shown in Tables 1 and 2.

(Example 2)
(Synthesis of polyurethane compounds having an aromatic ring structure)
300 parts by weight of bisphenol A diglycidyl ether acrylic acid adduct (trade name: Epoxy ester 3000A) and 710 parts by weight of ethyl acetate are placed in a 5-liter four-necked flask, and the internal temperature reaches 60 ° C. So warmed. As a synthesis catalyst, 0.2 part by mass of di-n-butyltin dilaurate was added, and 200 parts by mass of dicyclohexylmethane 4,4′-diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 1 hour with stirring. Reaction was continued for 2 hours after completion | finish of dripping, and 25 mass parts of diethylene glycol (made by Wako Pure Chemical Industries Ltd.) was dripped over 1 hour continuously. The reaction was continued for 5 hours after the dropwise addition to obtain a polyurethane compound having an aromatic ring structure with a weight average molecular weight of 20,000.

(Formation of undercoat layer)
As the polymer substrate 1, a polyethylene terephthalate film (“Lumirror” (registered trademark) U48 manufactured by Toray Industries, Inc.) having a thickness of 50 μm was used.

  As a coating liquid for forming an undercoat layer, 150 parts by mass of the polyurethane compound, 20 parts by mass of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: Light Acrylate DPE-6A), 1-hydroxy-cyclohexylphenyl- 5 parts by mass of ketone (BASF Japan, trade name: IRGACURE (registered trademark) 184), 3 parts by mass of 3-methacryloxypropylmethyldiethoxysilane (trade name: KBM-503, manufactured by Shin-Etsu Silicone), acetic acid A coating solution was prepared by blending 170 parts by mass of ethyl, 350 parts by mass of toluene and 170 parts by mass of cyclohexanone. The coating solution was applied onto the polymer substrate using a micro gravure coater (gravure wire number 150UR, gravure rotation ratio 100%) and dried at 100 ° C. for 1 minute. After drying, ultraviolet treatment was performed under the following conditions to provide an undercoat layer having a thickness of 1,000 nm.

Ultraviolet ray processing apparatus: LH10-10Q-G (manufactured by Fusion UV Systems Japan)
Introduced gas: N ₂ (nitrogen inert BOX)
Ultraviolet light source: Microwave type electrodeless lamp Integrated light quantity: 400 mJ / cm ²
Sample temperature control: room temperature.

Next, a 150 nm thick ZnO—SiO ₂ —Al ₂ O ₃ layer as a first layer and a 100 nm thick SiO ₂ layer as a _second layer were provided on the undercoat layer in the same manner as in Example 1. The obtained gas barrier film was evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2.

(Example 3)
A gas barrier film was obtained in the same manner as in Example 2 except that a ZnO—SiO ₂ —Al ₂ O ₃ layer having a thickness of 450 nm was provided as the first layer.

Example 4
A gas barrier film was obtained in the same manner as in Example 2 except that a ZnO—SiO ₂ —Al ₂ O ₃ layer having a thickness of 100 nm was provided as the first layer.

(Example 5)
A gas barrier film was obtained in the same manner as in Example 2 except that a SiO ₂ layer having a thickness of 400 nm was provided as the second layer.

(Example 6)
A gas barrier film was obtained in the same manner as in Example 2 except that a SiO ₂ layer having a thickness of 70 nm was provided as the second layer.

(Example 7)
A gas barrier film was obtained in the same manner as in Example 2 except that the main drum temperature at the time of forming the second layer was 110 ° C., and the SiO ₂ layer was provided to a thickness of 300 nm.

(Comparative Example 1)
A gas barrier film was obtained in the same manner as in Example 1 except that the SiO ₂ layer was not formed as the second layer.

(Comparative Example 2)
Except that the ZnO—SiO ₂ —Al ₂ O ₃ layer was not formed as the first layer, and the SiO ₂ layer was provided directly on the surface of the polymer substrate so as to have a thickness of 100 nm, the same as in Example 1. A gas barrier film was obtained.

(Comparative Example 3)
A gas barrier film was obtained in the same manner as in Example 2 except that the SiO ₂ layer was not formed as the second layer.

(Comparative Example 4)
As the formation condition of the first layer, the temperature of the main drum 10 is 25 ° C., the input power of the DC pulse power supply is 1,500 W, and as the formation condition of the second layer, the temperature of the main drum 10 is 25 ° C. A gas barrier film was obtained in the same manner as in Example 2 except that the input power of the induction coil was 500 W.

(Comparative Example 5)
A ZnO—SiO ₂ —Al ₂ O ₃ layer having a thickness of 450 nm is provided as the first layer, and the temperature of the main drum 10 is set to 25 ° C. as a formation condition of the second layer, and the input power of the induction coil of the CVD electrode is set to 500 W. A gas barrier film was obtained in the same manner as in Example 2 except that.

(Comparative Example 6)
The SiO ₂ layer was formed to a thickness of 100nm as a first layer, except that the _ZnO-SiO 2 _-Al 2 _{O 3} layer was formed to a thickness 150nm in the same manner as in Example 2 gas barrier film as a second layer Got.

(Comparative Example 7)
The second layer was formed in the same manner as in Example 2 except that the temperature of the main drum 10 was 25 ° C., the input power of the induction coil of the CVD electrode was 500 W, and the thickness of the SiO ₂ layer was 400 nm. Thus, a gas barrier film was obtained.

(Comparative Example 8)
A gas barrier film was obtained in the same manner as in Example 2 except that an Al ₂ O ₃ layer having a thickness of 100 nm was provided instead of the second SiO ₂ layer. The Al ₂ O ₃ layer is made of a sputter target, which is a mixed sintered material formed of zinc oxide, silicon dioxide, and aluminum oxide at the time of forming the ZnO—SiO ₂ —Al ₂ O ₃ layer, with a purity of 99.99% by mass. It was formed in the same manner as the first layer of Example 2 except that it was placed on the sputter electrode 12 instead of the sputter target made of aluminum. The composition of the second layer was an Al atom concentration of 37.5 atom% and an O atom concentration of 62.5 atom%.

(Comparative Example 9)
In Example 2, a gas barrier was used in the same manner as in Example 2 except that a sputter target made of aluminum having a purity of 99.99% by mass was used as the first layer and the Al ₂ O ₃ layer was provided to a thickness of 150 nm. A characteristic film was obtained. The composition of the first layer was an Al atom concentration of 37.5 atom% and an O atom concentration of 62.5 atom%.

(Comparative Example 10)
In Example 2, a gas barrier film was used in the same manner as in Example 2 except that a sputter target made of zinc oxide having a purity of 99.99% by mass was used as the first layer and the ZnO layer was provided to a thickness of 150 nm. Got. The composition of the first layer was such that the Zn atom concentration was 48.9 atom% and the O atom concentration was 51.1 atom%.

  Since the gas barrier film of the present invention is excellent in gas barrier properties against oxygen gas, water vapor, etc., it can be usefully used, for example, as a packaging material for foods, pharmaceuticals, etc., and as a member for electronic devices such as thin televisions and solar cells. However, the application is not limited to these.

DESCRIPTION OF SYMBOLS 1 Polymer base material 2 Gas barrier layer 2a 1st layer 2b containing zinc oxide and silicon dioxide 2nd layer 3 containing silicon compound 3 Undercoat layer 4 Winding-type sputtering and chemical vapor deposition apparatus 5 Winding chamber 6 Unwinding Rolls 7, 8, 9 Unwinding side guide roll 10 Main drum 11 Sputtering electrodes 12, 13, 14 Winding side guide roll 15 Winding roll 16 CVD electrode 17 Induction coil

Claims (8)

A gas barrier film having a gas barrier layer disposed on at least one surface of a polymer substrate, wherein the gas barrier layer is composed of a first layer containing zinc oxide and silicon dioxide and a second layer containing a silicon compound. The bonding energy of the Si2p orbitals at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is the Si2p orbital in the first layer. A gas barrier film that is larger than the binding energy of Si2p and smaller than the binding energy of Si2p orbitals in the second layer. The gas barrier film according to claim 1, wherein a half-value width of a binding energy peak of Zn2p3 / 2 orbit at the interface between the first layer and the second layer measured by X-ray photoelectron spectroscopy is 2.5 eV or more. . The gas barrier film according to claim 1 or 2, wherein the silicon compound contains at least one selected from the group consisting of silicon dioxide, silicon carbide, silicon nitride, and silicon oxynitride. The gas barrier film according to any one of claims 1 to 3, wherein the first layer further contains at least one element selected from the group consisting of aluminum, gallium, titanium, zirconium, tin, indium, niobium, molybdenum, and tantalum. . The structure according to claim 1, further comprising an undercoat layer between the polymer substrate and the first layer, wherein the undercoat layer includes a structure obtained by crosslinking a polyurethane compound having an aromatic ring structure. The gas barrier film according to any one of the above. The gas barrier film according to claim 1, wherein the first layer is made of zinc oxide, silicon dioxide, and aluminum oxide. The first layer has a zinc atom concentration of 10 to 35 atom%, a silicon atom concentration of 7 to 25 atom%, an aluminum atom concentration of 0.5 to 5 atom%, and an oxygen atom concentration of 45 to 45 as measured by X-ray photoelectron spectroscopy. It is 70 atom%, The gas barrier film in any one of Claims 1-6. The gas barrier film according to claim 1, wherein the second layer has a silicon atom concentration of 25 to 45 atom% and an oxygen atom concentration of 55 to 75 atom% as measured by X-ray photoelectron spectroscopy.

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