JP4310784B2 - High barrier sheet - Google Patents

Description

  The present invention relates to a high barrier sheet having excellent gas barrier properties against oxygen, water vapor and the like, and further having various properties such as high transparency, heat resistance and flexibility.

  Today, in the packaging field of foods, pharmaceuticals, etc., in order to maintain the taste, freshness, efficacy, etc. by suppressing the oxidation and alteration of the contents, the packaging material used has a high gas barrier property against the permeation of oxygen and water vapor. Is required. In particular, in packaging of foods, etc., in order to ensure the visibility of the contents and the packaging properties of various miscellaneous items, the packaging material has various characteristics such as transparency, heat resistance and flexibility in addition to the above gas barrier properties. Is required. In addition, even in new fields such as organic EL, organic thin-film solar cells, organic transistors, and flexible liquid crystals that are being developed today, high barrier properties having various properties such as high gas barrier properties, transparency, heat resistance, and flexibility. The development of seats is awaited.

As a conventional high-barrier sheet having various properties such as gas barrier properties and transparency, a synthetic resin base film 51 and a gas barrier laminated on the surface of the base film 51 are shown in FIG. Layer 52 (see, for example, JP-A-2003-181974). For the base film 51, a polyethylene terephthalate film or the like is used to improve heat resistance. The gas barrier layer 52 is composed of a deposited thin film of silicon oxide or aluminum oxide formed by physical vapor deposition or chemical vapor deposition.
JP 2003-181974 A

  The conventional high-barrier sheet has a predetermined gas barrier property due to the gas barrier layer 52. However, even if the manufacturing method and manufacturing conditions of the deposited thin film of silicon oxide or aluminum oxide are controlled, pinholes and crystals are formed in the gas barrier layer 52. Defects such as grain boundaries and cracks occur, and a gas such as water vapor passes through the defects in the gas barrier layer 52. Therefore, the conventional high-barrier sheet has a limit in improving the gas barrier property, and a barrier sheet for organic EL, a substrate sheet for organic thin-film solar cells, a substrate sheet for organic transistor, and a flexible film that require high gas barrier properties. It cannot withstand use as a liquid crystal substrate sheet or the like.

  The present invention has been made in view of these disadvantages, and has excellent gas barrier properties against oxygen, water vapor and the like, and has various properties such as high transparency, heat resistance and flexibility, and requires extremely high gas barrier properties. For example, the present invention aims to provide a high-barrier sheet suitably used for an organic EL barrier sheet, an organic thin film solar cell substrate sheet, an organic transistor substrate sheet, a flexible liquid crystal substrate sheet, and the like.

The invention made to solve the above problems is
A base film made of synthetic resin;
A gas barrier layer laminated on at least one surface of the base film;
A planarization layer laminated on the outer surface of the gas barrier layer,
The gas barrier layer is formed of an inorganic oxide or an inorganic nitride;
The planarizing layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof, and the gas barrier layer and the planarizing layer are repeatedly laminated in the same order several times. It is a high barrier sheet.
Here, the “outer surface” means a surface opposite to the base film.

  In the high barrier sheet, since a planarization layer is laminated on the outer surface of the gas barrier layer, even if defects such as pinholes, crystal grain boundaries, and cracks occur in the gas barrier layer, the defects are caused by the planarization layer. Blocked and protected. Therefore, the high barrier sheet further improves the gas barrier property against water vapor and the like, and the deterioration of the gas barrier property with time is reduced.

The gas barrier layer and the planarization layer are repeatedly laminated in the same order a plurality of times. Thus, the gas barrier property of the said high barrier property sheet | seat can be improved significantly by repeating and laminating | stacking a gas barrier layer and a planarization layer in multiple times in the same order. Further, the planarization layer laminated between the pair of gas barrier layers covers such surface defects even if defects such as pinholes, crystal grain boundaries, and cracks are present on the outer surface of the inner gas barrier layer, and the outer gas barrier layer. As a result of promoting the smoothness of the interface where the layers are laminated, the denseness of the outer gas barrier layer can be promoted. Therefore, in the high barrier sheet, the occurrence of defects such as pinholes, crystal grain boundaries, and cracks in the gas barrier layer in the second and subsequent stages is reduced, and the gas barrier property against water vapor and the like is remarkably improved.

The gas barrier layer is formed from an inorganic oxide or an inorganic nitride. Thus, by forming a gas barrier layer from an inorganic oxide or an inorganic nitride, the high gas barrier property of a gas barrier layer, transparency, heat resistance, a softness | flexibility, etc. are ensured.

  The inorganic oxide or inorganic nitride is preferably one or more selected from the group consisting of silicon oxide, silicon nitride, and aluminum oxide. By forming a gas barrier layer from such silicon oxide, silicon nitride, or aluminum oxide, the gas barrier property, transparency, etc. of the high barrier sheet are enhanced.

  The gas barrier layer may be formed by physical vapor deposition or chemical vapor deposition. Thus, by forming the gas barrier layer by physical vapor deposition or chemical vapor deposition, a dense and uniform gas barrier layer having high gas barrier properties can be formed.

  The physical vapor deposition method is preferably a sputtering method, and the chemical vapor deposition method is preferably a plasma chemical vapor deposition method. According to such a sputtering method, it is possible to form a vapor-deposited film (gas barrier layer) such as a dense and uniform inorganic oxide having a high gas barrier property. Moreover, according to plasma CVD, it is possible to form a vapor-deposited film (gas barrier layer) such as a dense inorganic oxide which is rich in adhesion and flexibility at a relatively low temperature.

The planarization layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof. According to the sol-gel method using the composition containing such a metal alkoxide and / or a hydrolyzate thereof, it has a defect sealing function for the inner gas barrier layer and a denseness promoting function for the outer gas barrier layer. The planarization layer can be formed easily and reliably. Further, by forming the planarization layer by the sol-gel method in this manner, the gas barrier property is also imparted to the planarization layer, and the gas barrier property of the high barrier sheet can be further improved.

  The composition may contain a metal alkoxide having a functional group containing at least one of nitrogen, oxygen, sulfur and halogen. Thus, by including a metal alkoxide having a functional group containing at least one of nitrogen, oxygen, sulfur and halogen, the film physical properties of the planarization layer are improved, and the denseness promoting function and defects for the above-mentioned gas barrier layer are improved. The sealing function and the gas barrier property of the planarizing layer can be promoted.

The composition may contain an organic solvent that can be used in the sol-gel method and / or a polymer that is soluble in water (hereinafter referred to as “solvent-soluble polymer”). Thus, by forming a planarization layer by a sol-gel method using a composition containing a metal alkoxide and a solvent-soluble polymer, the physical properties of the planarization layer are improved, and the gas barrier property of the planarization layer ( In particular, the gas barrier property at a high temperature can be further improved.

  In the formation of the planarizing layer by the sol-gel method, the composition may be subjected to ultraviolet irradiation with heating. In this way, when the planarization layer is formed by the sol-gel method, the composition is cured at a lower temperature by applying ultraviolet irradiation to the composition together with heating, and the film properties and the adhesion of the planarization layer are improved. improves. Therefore, the high barrier sheet has higher gas barrier properties, heat resistance, transparency, and the like.

  A surface treatment for promoting adhesion to the gas barrier layer may be performed on the gas barrier layer lamination surface of the base film. In this way, the adhesive strength between the base film and the gas barrier layer is improved by applying the surface treatment for improving the adhesion to the gas barrier layer lamination surface of the base film, and in addition, contributing to the formation of a dense and uniform gas barrier layer. As a result, film physical properties such as gas barrier properties, strength, and durability of the high barrier sheet can be further enhanced.

  As the surface treatment, a low temperature plasma treatment and / or an anchor coat treatment is preferable. According to such low temperature plasma treatment and / or anchor coat treatment, it is possible to effectively improve the adhesion between the base film made of synthetic resin and the gas barrier layer formed by vapor deposition of an inorganic oxide or the like.

  As described above, the high barrier sheet of the present invention has excellent gas barrier properties against oxygen, water vapor, and the like, and has various properties such as high transparency, heat resistance, and flexibility. Therefore, the high barrier sheet is suitably used for, for example, an organic EL barrier sheet, an organic thin film solar cell substrate sheet, an organic transistor substrate sheet, a flexible liquid crystal substrate sheet, etc., which require extremely high gas barrier properties. Is done.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is a schematic cross-sectional view showing a high-barrier sheet according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view showing a high-barrier sheet according to a form different from the high-barrier sheet of FIG. .

  The high barrier sheet in FIG. 1 includes a base film 1 made of synthetic resin, a gas barrier layer 2 laminated on one surface of the base film 1, and a planarization layer laminated on the outer surface of the gas barrier layer 2. 3 is provided. The high-barrier sheet has a high gas barrier property mainly due to the gas barrier layer 2 and also has various properties such as high transparency, heat resistance, and flexibility.

  The base film 1 is formed by sheet molding using a synthetic resin as a material. The synthetic resin used for the base film 1 is not particularly limited, and for example, a polyethylene resin, a polypropylene resin, a cyclic polyolefin resin, a polystyrene resin, an acrylonitrile-styrene copolymer (AS resin), Acrylonitrile-butadiene-styrene copolymer (ABS resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyester resin, polyamide resin, polyimide resin, polyamideimide Examples thereof include resins, polyaryl phthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyether sulfone resins, polyurethane resins, acetal resins, and cellulose resins. Among the above resins, polyester resins, fluorine resins, and cyclic polyolefin resins that have high heat resistance, strength, weather resistance, durability, gas barrier properties against water vapor, and the like and withstand the vapor deposition conditions of the gas barrier layer 2 are preferable. .

  Examples of the polyester resin include polyethylene terephthalate and polyethylene naphthalate. Among these polyester-based resins, polyethylene terephthalate is particularly preferable because it has a good balance between various functions such as heat resistance and weather resistance, and price.

  Examples of the fluororesin include polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA) made of a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, and a copolymer of tetrafluoroethylene and hexafluoropropylene (FEP). Copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether and hexafluoropropylene (EPE), copolymer of tetrafluoroethylene and ethylene or propylene (ETFE), polychlorotrifluoroethylene resin (PCTFE), ethylene and chlorotrifluoroethylene Copolymer (ECTFE), vinylidene fluoride resin (PVDF), vinyl fluoride resin (PVF), and the like. Among these fluororesins, polyvinyl fluoride resin (PVF) and a copolymer of tetrafluoroethylene and ethylene or propylene (ETFE) which are excellent in strength, heat resistance, weather resistance and the like are particularly preferable.

  As the cyclic polyolefin resin, for example, a) cyclic dienes such as cyclopentadiene (and derivatives thereof), dicyclopentadiene (and derivatives thereof), cyclohexadiene (and derivatives thereof), norbornadiene (and derivatives thereof) are polymerized. And b) a copolymer obtained by copolymerizing the cyclic diene with one or more olefinic monomers such as ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, and isoprene. . Among these cyclic polyolefin resins, cyclopentadiene (and derivatives thereof), dicyclopentadiene (and derivatives thereof) or norbornadiene (and derivatives thereof) such as polymers having excellent strength, heat resistance, and weather resistance are particularly preferred. preferable.

  In addition, as a forming material of the base film 1, the said synthetic resin can be used 1 type or in mixture of 2 or more types. In addition, various additives and the like can be mixed in the forming material of the base film 1 for the purpose of improving and modifying processability, heat resistance, weather resistance, mechanical properties, dimensional stability, and the like. . Examples of the additive include a lubricant, a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, a reinforcing fiber, a reinforcing agent, an antistatic agent, a flame retardant, a flame retardant, a foaming agent, and an antifungal agent. And pigments. The method for forming the base film 1 is not particularly limited, and known methods such as an extrusion method, a cast forming method, a T-die method, a cutting method, and an inflation method are employed.

  As a minimum of thickness (average thickness) of substrate film 1, 10 micrometers is preferred and 20 micrometers is especially preferred. On the other hand, the upper limit of the thickness of the base film 1 is preferably 250 μm and particularly preferably 188 μm. When the thickness of the base film 1 is less than the above lower limit, problems such as curl are likely to occur during vapor deposition for forming the gas barrier layer 2 and handling becomes difficult. On the other hand, if the thickness of the base film 1 exceeds the above upper limit, it is contrary to the demand for thinning and lightening the high barrier sheet.

  Further, the gas barrier layer laminated surface of the base film 1 may be subjected to a surface treatment for improving the tight adhesion with the gas barrier layer 2. Examples of such adhesion improving surface treatment include (a) corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, and the like ( b) Primer coat treatment, undercoat treatment, anchor coat treatment, vapor deposition anchor coat treatment and the like. Among these surface treatments, a low temperature plasma treatment is preferable, in which a hydroxyl group is generated on the surface of the base film 1 and the adhesion strength with the gas barrier layer 2 which is a deposited film of an inorganic oxide or the like is improved. An anchor coat treatment that contributes to the formation of a dense and uniform gas barrier layer 2 is preferable.

  Examples of the anchor coating agent used for the anchor coating treatment include a polyester anchor coating agent, a polyamide anchor coating agent, a polyurethane anchor coating agent, an epoxy anchor coating agent, a phenol anchor coating agent, and a (meth) acrylic anchor coating. Agents, polyvinyl acetate anchor coating agents, polyolefin anchor coating agents such as polyethylene aly polypropylene, and cellulose anchor coating agents. Among these anchor coating agents, polyester anchor coating agents that can further improve the adhesive strength between the base film 1 and the gas barrier layer 2 are particularly preferable.

The lower limit of the coating amount of the anchor coating agent (solid content) is preferably ^{0.1g / m 2, 1g / m} 2 is particularly preferred. In contrast, the upper limit of the amount of coating of the anchor coating agent is preferably ^{5g / m 2, 3g / m} 2 is particularly preferred. If the coating amount of the anchor coating agent is smaller than the lower limit, the effect of improving the adhesion between the base film 1 and the gas barrier layer 2 may be reduced. On the other hand, when the coating amount of the anchor coating agent exceeds the above upper limit, the strength, durability and the like of the high barrier sheet may be lowered.

  In the anchor coating agent, a silane coupling agent for improving tight adhesion, a blocking inhibitor for preventing blocking with the base film 1, an ultraviolet absorber for improving weather resistance, etc. These various additives can be appropriately mixed. The amount of the additive to be mixed is preferably 0.1% by weight or more and 10% by weight or less from the balance between the effect expression of the additive and the function inhibition of the anchor coating agent.

The gas barrier layer 2 is laminated on one surface of the base film 1 and is formed by depositing an inorganic oxide or an inorganic nitride by physical vapor deposition or chemical vapor deposition. As this inorganic oxide or inorganic nitride, for example, silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B ), Titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y), and other oxides or nitrides. Of the inorganic oxides and inorganic nitrides, silicon oxides, silicon nitrides, and aluminum oxides that are excellent in gas barrier properties, transparency, flexibility, and the like are preferable, and one or more selected from these groups Those are preferably used. Among these, silicon oxides having good gas barrier properties, transparency, flexibility, adhesion, and the like are particularly preferable. The inorganic oxide is expressed by MO _X (M represents a metal element, X represents the degree of oxidation) such as SiO _X , AlO _X, etc., but silicon (Si) is used from the viewpoint of gas barrier properties and transparency. In this case, the oxidation degree X is preferably in the range of 1.3 to 1.9, and in the case of aluminum (Al), the oxidation degree X is preferably in the range of 0.5 to 1.5.

  Examples of the physical vapor deposition method (Physical Vapor Deposition method; PVD method) include a vacuum deposition method, a sputtering method, an ion plating method, and an ion cluster beam method. Specifically, (a) a metal oxide is used as a raw material, this is heated, vaporized and vapor deposited on the base film 1, (b) a metal or metal oxide is used as the raw material, If necessary, a reactive deposition method in which oxygen gas or the like is introduced to oxidize and deposit on the planarizing layer 3, and (c) a plasma-assisted reactive deposition method in which a reaction such as oxidation is further promoted by plasma. Etc. can be used to form a metal oxide vapor-deposited film. As a heating method for the vapor deposition material, for example, a resistance heating method, a high frequency induction heating method, an electron beam heating method (EB), or the like can be used. Among the physical vapor deposition methods, a sputtering method is particularly preferable because the vaporization of inorganic oxide or inorganic nitride is easy.

  Examples of the chemical vapor deposition method (Chemical Vapor Deposition method; CVD method) include a plasma chemical vapor deposition method, a thermal chemical vapor deposition method, and a photochemical vapor deposition method. Among these chemical vapor deposition methods, plasma CVD capable of forming the gas barrier layer 2 at a relatively low temperature is particularly preferable. Specifically, plasma CVD uses a vapor deposition monomer gas such as an organosilicon compound as a raw material, uses an inert gas such as argon or helium as a carrier gas, and further supplies oxygen gas, ammonia gas, etc. In this method, a chemical reaction is caused by using a generator or the like to form a deposited thin film of an inorganic oxide or nitride such as silicon oxide on the base film 1. As this low-temperature plasma generator, for example, generators such as high-frequency plasma, pulse wave plasma, and microwave plasma can be used, and a generator using a high-frequency plasma system that can obtain highly active and stable plasma is particularly preferable. .

  Examples of a monomer gas for vapor deposition of an organic silicon compound or the like that forms a vapor deposition thin film of an inorganic oxide such as silicon oxide include 1.1.3.3-tetramethyldisiloxane, hexamethyldisiloxane, vinyltrimethylsilane, and methyltrimethyl. Silane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane , Octamethylcyclotetrasiloxane, and the like can be used. Among these monomer gases for vapor deposition, 1.1.3.3-tetramethyldisiloxane and hexamethyldisiloxane, which have good handling properties and physical properties of the vapor deposition film, are preferable.

  The gas barrier layer 2 may have a single layer structure or a multilayer structure of two or more layers. As described above, the gas barrier layer 2 has a multi-layer structure, so that the deterioration of the base film 1 is reduced by reducing the heat load applied during vapor deposition, and the adhesion between the base film 1 and the gas barrier layer 2 is improved. can do. The vapor deposition conditions in the physical vapor deposition method and the chemical vapor deposition method are appropriately designed according to the resin type of the base film 1, the thickness of the gas barrier layer 2, and the like.

  As a minimum of the thickness (average thickness) of gas barrier layer 2, 10 nm is preferred and 20 nm is especially preferred. On the other hand, the upper limit of the thickness of the gas barrier layer 2 is preferably 200 nm, and particularly preferably 100 nm. If the thickness of the gas barrier layer 2 is smaller than the lower limit, the gas barrier property may be lowered. On the other hand, when the thickness of the gas barrier layer 2 exceeds the above upper limit, the flexibility is lowered and defects such as cracks are likely to occur in the gas barrier layer 2.

  The planarization layer 3 is laminated on the outer surface of the gas barrier layer 2 and is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof.

  Examples of the metal contained in the metal alkoxide include trivalent or higher metals, for example, transition metals, rare earth metals, metals in groups 3 to 5 of the periodic table, and metals belonging to groups 3b or 4 of the periodic table are preferable. Examples of the metal belonging to Group 3b of the periodic table include Al. Examples of the metal belonging to Group 4 of the periodic table include Ti and Zr belonging to Group 4a, Si and the like belonging to Group 4b. Of these metals, Al and Si, which are easy to form a film by a sol-gel method and have an excellent interface flattening function, are preferable, and Si is particularly preferable.

  Examples of the alkoxy group possessed by the metal alkoxide include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a pentyloxy group, and a hexyloxy group. Among them, a lower alkoxy group having 1 to 4 carbon atoms that is excellent in hydrolysis polymerizability is preferable, and a methoxy group, an ethoxy group, and a propoxy group are particularly preferable. In addition, a metal alkoxide having at least two alkoxy groups is preferred for the purpose of promoting hydrolysis polymerizability.

  The metal alkoxide may have a hydrocarbon group. Examples of the hydrocarbon group include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, and a hexyl group; a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group; a phenyl group Aryl groups such as naphthyl group; aralkyl groups such as benzyl group and 2-phenylethyl group. Of these hydrocarbon groups, alkyl groups and aryl groups are preferred. Among these alkyl groups, a lower alkyl group having 1 to 4 carbon atoms is preferable, and a methyl group, an ethyl group, and a propyl group are particularly preferable. Of the aryl groups, a phenyl group is preferable. The number of hydrocarbon groups in the metal alkoxide can be appropriately selected according to the number of alkoxy groups, and is generally about 0 to 2 in one molecule.

Specifically, the metal alkoxide is preferably represented by the following formula (1).
(R ¹ ) _m M (OR ² ) _Xm (1)
In the above formula (1), R ¹ represents an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group, and may have a substituent. R ² represents a lower alkyl group. R ¹ and R ² may be different depending on m. M represents a trivalent or higher metal. X represents the valence of the metal M. m shows the integer of 0-2 and it is Xm> = 2.

In particular, the metal alkoxide whose metal is Si is preferably represented by the following formula (2).
(R ¹ ) _n Si (OR ² ) _4-n (2)
In the above formula (2), R ¹ represents an alkyl group or an aryl group, and may have a substituent. R ² represents a lower alkyl group. R ¹ and R ² may be different depending on n. n shows the integer of 0-2.

  Specific examples of the metal alkoxide whose metal is Al include trimethoxy aluminate, triethoxy aluminate, ethyl diethoxy aluminate, tripropoxy aluminate and the like.

  Specific examples of the metal (Si) alkoxide represented by the above formula (2) include tetramethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, tetraethoxysilane, and methyl. Triethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, butyltriethoxysilane, tetrapropoxysilane, methyltripropoxysilane, ethyltripropoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, dipropyldimethoxysilane, dimethyldiethoxysilane , Diethyldiethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptop Pills triethoxysilane, .gamma.-aminopropyltrimethoxysilane, .gamma.-aminopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltrimethoxysilane propoxy, diphenyldimethoxysilane, and the like diphenyl diethoxy silane.

  Among metal (Si) alkoxides represented by the above formula (2), 0 to 2 alkyl groups or aryl groups having about 1 to 4 carbon atoms, and 2 to 4 alkoxy groups having about 1 to 3 carbon atoms. Compounds such as tetramethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, methyltriethoxysilane, tetraethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane Etc. are particularly preferred.

  In addition, in the said composition, the same kind or different kind of metal alkoxide can be used 1 type or in mixture of 2 or more types. Further, in order to adjust the hardness, flexibility and the like of the composition, n = 3 monoalkoxysilane may be added to the composition. Further, in the above composition, a group 5b compound such as methylphosphonas dimethyl ester, ethylphosphonas dimethyl ester, trichloromethylphosphonas diethyl ester, methylphosphonas diethyl ester, methylphosphonic dimethyl ester, phenylphosphonic dimethyl ester Phosphorus compounds such as esters and trialkyl phosphates and boron compounds such as boric acid trialkyl esters may be added. Further, an alkaline earth metal compound having at least one hydrolyzable organic group may be added to the composition as necessary. This alkaline earth metal compound may have both a hydrocarbon group and a hydrolyzable organic group.

  The composition may contain a metal alkoxide (A) having a functional group containing at least one of nitrogen, oxygen, sulfur and halogen. Thus, by applying and curing the composition containing the metal alkoxide (A) having a functional group containing at least one of nitrogen, oxygen, sulfur, and halogen, a specific polysiloxane structure is formed on the planarizing layer 3. It is possible to improve the film physical properties of the planarization layer 3 and thus the gas barrier property, and in addition, the temperature dependence of the gas barrier property of the planarization layer 3 can be reduced.

  Examples of the functional group containing at least one of nitrogen, oxygen, sulfur and halogen include an amino group, chlorine, mercapto group, and glycidoxy group. Examples of the metal alkoxide (A) having a functional group containing at least one of nitrogen, oxygen, sulfur and halogen include γ-chloropropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. , Γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β (amino Ethyl) -γ-aminopropylmethyldimethoxysilane, γ-ureidopropyltriethoxysilane, bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-aminopropylsilicone, and the like. Use one or more alkoxides Door can be.

  As content (content with respect to all the metal alkoxides in a composition) of the said metal alkoxide (A), 1 to 50 mass% is preferable, and 3 to 30 mass% is especially preferable. By setting the content of the metal alkoxide (A) in the above range, a polysiloxane structure contributing to gas barrier properties can be expressed in the planarizing layer 3.

  A solvent-soluble polymer may be contained in the composition. By forming the planarizing layer 3 by a sol-gel method using a composition containing such a solvent-soluble polymer and a metal alkoxide, the film physical properties of the planarizing layer 3 are improved, and the gas barrier property ( In particular, the gas barrier property at a high temperature can be further improved.

Examples of the solvent-soluble polymer include polymers having various functional groups and functional bonding groups (for example, hydroxyl groups, carboxyl groups, ester bonds, ether bonds, carbonate bonds, amide groups, amide bonds, etc.), polymers having glycidyl groups. , Halogen-containing polymers, and derivatives from these polymers. These functional groups and functional binding groups may be present in either the main chain or the side chain of the polymer. The solvent-soluble polymer may be either a thermoplastic resin or a thermosetting resin, and may be used alone or in combination of two or more. The solvent-soluble polymer may be active in the reaction with the metal alkoxide or may be inactive, but is generally a non-reactive polymer. The “amide bond” is not limited to —NHC (O) — and is a concept including a> NC (O) — bond unit.

  Examples of the hydroxyl group-containing polymer and derivatives thereof include polyvinyl alcohol, polyvinyl acetal, ethylene-vinyl alcohol copolymer, phenol resin, methylol melamine, and derivatives thereof (for example, acetalized products, hexamethoxymethyl melamine, etc.). . Examples of the carboxyl-containing polymer and derivatives thereof include homopolymers or copolymers containing units of polymerizable unsaturated acids such as poly (meth) acrylic acid, maleic anhydride, and itaconic acid, and esterified products of these polymers. Can be mentioned. Examples of the polymer having an ester bond include homopolymers or copolymers (for example, polyvinyl acetate, ethylene-vinyl acetate copolymer, etc.) containing units such as vinyl esters such as vinyl acetate and (meth) acrylic esters such as methyl methacrylate. Coalescence, (meth) acrylic resin, etc.), saturated polyester, unsaturated polyester, vinyl ester resin, diallyl phthalate resin, cellulose ester and the like. Examples of the polymer having an ether bond include polyalkylene oxide, polyoxyalkylene glycol, polyvinyl ether, and silicon resin. Examples of the polymer having a carbonate bond include polycarbonates such as bisphenol A polycarbonate.

  Examples of the polymer having an amide bond include:> N (COR) -bonded polyoxazoline, polyalkyleneimine and other N-acylated products;> NC (O) -bonded polyvinylpyrrolidone and derivatives thereof; urethane bond- Includes polyurethanes with HNC (O) O—; polymers with urea linkages—HNC (O) NH—; polymers with amide linkages—C (O) NH—; polymers with bullet linkages; polymers with allophanate linkages, etc. It is. In the above bonding formula, R represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent.

  In the case of a polyoxazoline having> N (COR) -bond, the alkyl group represented by R is, for example, an alkyl group having about 1 to 10 carbon atoms, preferably a lower alkyl group having 1 to 4 carbon atoms, particularly a methyl group. , Ethyl group, propyl group, isopropyl group and the like. Examples of the substituent of the alkyl group include halogen atoms such as fluorine, chlorine and bromine, hydroxyl groups, alkoxy groups having about 1 to 4 carbon atoms, carboxyl groups, and alkoxycarbonyl groups having about 1 to 4 carbon atoms in the alkyl portion. Is mentioned. Examples of the aryl group include phenyl and naphthyl groups. Examples of the substituent of the aryl group include the halogen atom, an alkyl group having about 1 to 4 carbon atoms, a hydroxyl group, an alkoxy group having about 1 to 4 carbon atoms, a carboxyl group, and an alkyl moiety having about 1 to 4 carbon atoms. An alkoxycarbonyl group etc. are mentioned.

  Examples of oxazolines include 2-oxazoline, 2-methyl-2-oxazoline, 2-ethyl-2-oxazoline, 2-propyl-2-oxazoline, 2-isopropyl-2-oxazoline, 2-butyl-2-oxazoline, 2 -Dichloromethyl-2-oxazoline, 2-trichloromethyl-2-oxazoline, 2-pentafluoroethyl-2-oxazoline, 2-phenyl-2-oxazoline, 2-methoxycarbonylethyl-2-oxazoline, 2- (4- Methylphenyl) -2-oxazoline, 2- (4-chlorophenyl) -2-oxazoline and the like. In particular, 2-oxazoline, 2-methyl-2-oxazoline, 2-ethyl-2-oxazoline and the like are preferable. Such oxazoline polymers can be used singly or in combination. The polyoxazoline may be a homopolymer or a copolymer. The polyoxazoline may be a copolymer obtained by grafting polyoxazoline to a polymer.

  The polyoxazoline can be obtained by ring-opening polymerization of an oxazoline which may have a substituent in the presence of a catalyst. Examples of the catalyst include sulfuric acid esters and sulfonic acid esters such as dimethyl sulfate and p-toluenesulfonic acid alkyl ester; alkyl halides such as alkyl iodide (for example, methyl iodide); metal fluorides among Friedel-Crafts catalysts; Acids such as sulfuric acid, hydrogen iodide and p-toluenesulfonic acid, and oxazolinium salts which are salts of these acids with oxazoline can be used.

  Examples of the acylated product of polyalkyleneimine include polymers corresponding to the polyoxazoline, for example, polymers having an N-acylamino group such as N-acetylamino and N-propionylamino. Examples of polyvinyl pyrrolidone and derivatives thereof include polymers of vinyl pyrrolidone which may have a substituent, such as polyvinyl pyrrolidone. Examples of polyurethanes having urethane bonds include polyisocyanates (tolylene diisocyanate, hexamethylene diisocyanate, etc.) and polyols (polyhydric alcohols such as ethylene glycol, propylene glycol, tetramethylene glycol, glycerin; diethylene glycol, polyethylene glycol, dipropylene glycol). And polyurethanes produced by reaction with polyether polyols such as polypropylene glycol; polyester polyols, etc.). Examples of the polymer having a urea bond include polyurea, a polymer formed by a reaction of polyisocyanate and polyamine (for example, diamine such as ethylenediamine and diethylenetriamine).

  Examples of the polymer having an amide bond include polyamide, poly (meth) acrylamide, and polyamino acid. The polymer having an amide bond is preferably an oxazoline polymer which may have a substituent, an N-acylated product of polyalkyleneimine, polyvinyl pyrrolidone, polyurethane, polyamide, poly (meth) acrylamide or the like. Examples of the polymer having a buret bond include a polymer produced by a reaction between the polyisocyanate and a compound having a urethane bond. Examples of the polymer having an allophanate bond include a polymer produced by a reaction between the polyisocyanate and a compound having a urea bond. Examples of the polymer having a glycidyl group include epoxy resins and glycidyl (meth) acrylate homopolymers or copolymers. Examples of the halogen-containing polymer include polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinylidene chloride-based polymer having vinylidene chloride units, and chlorinated polypropylene.

Solvent-soluble polymers are generally water; alcohols such as methanol, ethanol, propanol, isopropanol, butanol and cyclohexanol; aliphatic hydrocarbons such as hexane and octane; alicyclic hydrocarbons such as cyclohexane; Aromatic hydrocarbons such as benzene, toluene and xylene; Halogenated hydrocarbons such as methyl chloride, methylene chloride, chloroform and trichloroethylene; Esters such as methyl acetate, ethyl acetate and butyl acetate; Ketones such as acetone and methyl ethyl ketone; Ethers such as diethyl ether, dioxane, dimethoxyethane, tetrahydrofuran; nitrogen-containing solvents (eg, nitriles such as N-methylpyrrolidone and acetonitrile; amides such as dimethylformamide and dimethylacetamide) and sulfo Aprotic polar solvents such as earth (such as dimethyl sulfoxide, etc.); or soluble in a mixed solvent thereof.

As the solvent-soluble polymer, those having a hydrogen bondable group, for example, a hydroxyl group, a carboxyl group, an amide group, an amide bond or a nitrogen atom are preferable. When such a solvent-soluble polymer having a hydrogen-bondable group is used, it is often possible to use a good solvent common to the metal alkoxide and / or its hydrolyzate. It is considered that the hydroxyl group of the metal polymer and the functional group or bonding group of the solvent-soluble polymer form a hydrogen bond, thereby forming a uniform organic / inorganic hybrid and forming a microscopically uniform and transparent film.

Moreover, as a solvent soluble polymer, the alcohol soluble polymer which can use a common solvent with a metal alkoxide is preferable. As such an alcohol-soluble polymer, a water-soluble polymer such as a polymer having a hydroxyl group is preferable, and a polymer having a nitrogen atom (for example, a polymer having the amide bond) is particularly preferable.

The content of the solvent-soluble polymer with respect to 100 parts by mass of the metal alkoxide (including the hydrolyzate thereof) is preferably 40% by mass to 90% by mass, and particularly preferably 50% by mass to 80% by mass. If the content of the solvent-soluble polymer is smaller than the above range, the effect of improving the gas barrier property is lowered, and it may be difficult to form a uniform film with a composite of an inorganic polymer and an organic polymer. On the other hand, when the content of the solvent-soluble polymer exceeds the above range, the film formability and uniformity tend to be improved, but the gas barrier property may be lowered.

In general, an organic solvent is blended in the composition. As this organic solvent, an appropriate solvent inert to the polymerization reaction depending on the type of metal alkoxide, for example, alcohols, aromatic hydrocarbons, ethers, nitrogen-containing solvents, sulfoxides, or a mixed solvent thereof is used. Is done. Moreover, the said solvent soluble polymer can also be used as an organic solvent. As the organic solvent, a solvent miscible with the metal alkoxide solvent is preferable, and a good solvent common to the solvent-soluble polymer and the metal alkoxide is particularly preferable.

  The composition may contain a curing catalyst, and the hydrolysis polymerization of the metal alkoxide may be performed in the presence of the curing catalyst. As the curing catalyst, tertiary amines and acid catalysts which are substantially insoluble in water and soluble in an organic solvent are used. Tertiary amines include, for example, N.I. N-dimethylbenzylamine, tripropylamine, tributylamine, tripentylamine and the like can be mentioned. Examples of the acid catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; carboxylic acids such as formic acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, and propionic acid, methanesulfonic acid, ethanesulfonic acid, and p-toluenesulfone. Examples thereof include organic acids such as sulfonic acids such as acids.

  In the composition for forming the flattening layer 3, various kinds of plasticizer, antioxidant, ultraviolet absorber, flame retardant, antistatic agent, surfactant, filler, colorant, etc. These additives may be appropriately blended.

  Next, a method for forming the planarizing layer 3 will be described. The planarizing layer 3 is formed by a sol-gel method using the above composition containing a metal alkoxide and / or a hydrolyzate thereof. Specifically, a solvent-soluble polymer, a curing catalyst, an organic solvent, and the like are appropriately added to a metal alkoxide and / or a hydrolyzate thereof, and the mixture is sufficiently kneaded to prepare the above composition. -The surface of the gas barrier layer 2 is coated by a coating method, then dried by heating, and further subjected to an aging treatment or the like, thereby forming a flattened layer 3 which is a cured coating film. The heating temperature is appropriately selected according to the hydrolyzability of the metal alkoxide and the heat resistance of the base film 1, but is preferably 50 ° C or higher and 120 ° C or lower. The polymerization reaction may be performed in the presence of an inert gas or may be performed under reduced pressure. Moreover, you may superpose | polymerize, removing the alcohol produced | generated with hydrolysis polymerization.

  In the method for forming the planarizing layer 3, the composition may be irradiated with ultraviolet rays during the heating step. In this way, the composition is cured at a lower temperature (100 ° C. or less) by irradiating the composition with ultraviolet rays during the heating step of the sol-gel method, and the flattening layer 3 has significantly fewer defects. Excellent physical properties and improved adhesion between the planarization layer 3 and the gas barrier layer 2. Therefore, the gas barrier property of the planarization layer 3 is further improved.

  In the high barrier sheet, even if defects such as pinholes, crystal grain boundaries, and cracks occur in the gas barrier layer 2, the defects are sealed off by the planarization layer 3. Further, in the high barrier sheet, the outer surface of the gas barrier layer 2 that mainly exhibits gas barrier properties is protected by the planarization layer 3, and the deterioration of the gas barrier properties with time is suppressed. Furthermore, in addition to the high gas barrier property of the gas barrier layer 2, the high barrier property sheet also contributes to the improvement of the gas barrier property by the planarization layer 3 laminated on the outer surface of the gas barrier layer 2. Therefore, the high barrier sheet significantly improves the gas barrier property against water vapor and the like, and the deterioration of the gas barrier property with time is reduced.

  The high barrier sheet of FIG. 2 includes a base film 1 made of synthetic resin, a gas barrier layer 2 laminated on one surface of the base film 1, and a planarization layer laminated on the outer surface of the gas barrier layer 2. 3, another gas barrier layer 2 stacked on the outer surface of the planarizing layer 3, and another planarizing layer 3 stacked on the outer surface of the other gas barrier layer 2. In other words, in the high barrier sheet, the gas barrier layer 2 and the planarizing layer 3 are repeatedly laminated in this order twice on one surface of the base film 1. The base film 1, gas barrier layer 2 and planarization layer 3 of the high barrier sheet are the same as the high barrier sheet of FIG. The other gas barrier layers 2 and other planarization layers 3 that are repeatedly stacked on the outer surface of the planarization layer 3 are the same as the first-stage gas barrier layer 2 and the planarization layer 3.

  Since the high barrier sheet includes two gas barrier layers 2 having high gas barrier properties and two planarization layers 3 having predetermined gas barrier properties, it has very high gas barrier properties and high transparency. It has various properties such as heat resistance, heat resistance and flexibility. In the high barrier sheet, even if defects such as pinholes, crystal grain boundaries, and cracks occur in the gas barrier layer 2, the defects are sealed and protected by the planarization layer 3, and gas barrier properties are promoted. . Further, the high barrier sheet is covered with the planarizing layer 3 even if there are defects such as pinholes and cracks on the outer surface of the inner gas barrier layer 2 as described above, and the interface of the outer gas barrier layer 2 is laminated. As a result of promoting smoothness, the growth of a dense and uniform deposited film such as an inorganic oxide is promoted in the formation of the outer gas barrier layer 2. Therefore, in the high barrier sheet, the occurrence of defects such as pinholes, crystal grain boundaries, and cracks in the outer gas barrier layer 2 is reduced, and the gas barrier property is further improved. That is, the planarization layer 3 laminated between the pair of gas barrier layers 2 is dense due to the smoothness of the interface with respect to the gas barrier layer 2 laminated on the outer side, in addition to the defect sealing function with respect to the inner gas barrier layer 2. In addition, a uniform vapor deposition film growth promoting function can be achieved.

  The high barrier sheet of the present invention is not limited to the above embodiment, and for example, a high barrier sheet having a structure in which the gas barrier layer 2 and the planarizing layer 3 are repeatedly laminated three or more times in this order is also possible. . As described above, by laminating three or more gas barrier layers 2 and the planarizing layer 3, various characteristics such as gas barrier properties, weather resistance, and durability can be remarkably improved.

  EXAMPLES Hereinafter, although this invention is explained in full detail based on an Example, this invention is not interpreted limitedly based on description of this Example.

[Example 1]
A base film made of transparent polyethylene terephthalate having a thickness of 25 μm was used, and silicon oxide (degree of oxidation X = about 1.8) was deposited on one surface of this base film by a sputtering method to have a thickness of 100 nm. A gas barrier layer was laminated. Next, for a flattening layer containing 34 parts by mass of tetraethoxysilane, 15 parts by mass of water, 10 parts by mass of isopropyl alcohol, 0.17 parts by mass of a tertiary amine, and 3.4 parts by mass of γ-glycidoxypropyltrimethoxysilane The composition was coated on the outer surface of the gas barrier layer by a gravure roll coating method at 1.0 g / m ² (dry state) and heat-treated at 120 ° C. for 1 minute to laminate a planarization layer. Through this process, the high barrier sheet of Example 1 was obtained.

[Example 2]
The high barrier of Example 2 except that the content of tetraethoxysilane was 20 parts by mass and 14 parts by mass of γ-aminopropyltrimethoxysilane was further contained in the flattening layer composition. Sex sheet was obtained.

[Example 3]
A high barrier sheet of Example 3 was obtained in the same manner as in Example 1 except that 35 parts by mass of alcohol-soluble copolymer nylon (manufactured by Toray Industries, Inc.) was contained in the composition for flattening layer.

[Example 4]
In the step of forming the flattening layer, the heat treatment temperature was set to 90 ° C., and in addition, the coating surface was irradiated with ultraviolet light having a wavelength of 210 nm for 10 minutes during the heat treatment. A high barrier sheet was obtained.

[Example 5]
A high barrier sheet of Example 5 was obtained in the same manner as in Example 1 except that the thickness of the gas barrier layer was 10 nm.

[Example 6]
A high barrier sheet of Example 6 was obtained in the same manner as in Example 1 except that the thickness of the gas barrier layer was 20 nm.

[Example 7]
A high barrier sheet of Example 7 was obtained in the same manner as in Example 1 except that the thickness of the gas barrier layer was 50 nm.

[Example 8]
A high barrier sheet of Example 8 was obtained in the same manner as in Example 1 except that the thickness of the gas barrier layer was 200 nm.

[Example 9]
A high barrier sheet of Example 9 was obtained in the same manner as in Example 1 except that a gas barrier layer and a planarizing layer were further repeatedly laminated in the same order on the outer surface of the planarizing layer. The second-stage gas barrier layer and planarization layer were formed by the same method as the first-stage gas barrier layer and planarization layer.

[Comparative example]
A high barrier sheet of a comparative example was obtained in the same manner as in Example 1 except that the planarizing layer was not laminated.

[Evaluation of characteristics]
Using the high barrier sheet of Examples 1 to 9 and the high barrier sheet of the comparative example, the water vapor permeability of these high barrier sheets was measured. This water vapor permeability was measured under the conditions of a temperature of 40 ° C. and a relative humidity of 90% in accordance with the JIS-Z-0208B method. The results are shown in Table 1 below.

  As shown in Table 1 above, compared to the high barrier sheet of the comparative example, which is a laminate of the base film and the gas barrier layer, the height of Examples 1 to 9 in which the planarizing layer is laminated on the outer surface of the gas barrier layer The barrier sheet has a high gas barrier property. Further, when comparing the high barrier sheets of Examples 1, 5, 6, 7, and 8, the higher the gas barrier layer, the higher the gas barrier property. Further, the high barrier sheets of Examples 2, 3, 4 and 9 have better gas barrier properties.

  As described above, the high-barrier sheet of the present invention is useful as a packaging material for foods, pharmaceuticals, etc., and is particularly composed of organic EL, organic thin-film solar cells, organic transistors, flexible liquid crystals and the like that are being developed today. It is suitably used as a material.

It is a typical sectional view showing the high barrier property sheet concerning one embodiment of the present invention. It is typical sectional drawing which shows the high barrier property sheet | seat which concerns on the form different from the high barrier property sheet | seat of FIG. It is typical sectional drawing which shows the conventional general high barrier property sheet | seat.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base film 2 Gas barrier layer 3 Flattening layer

Claims (10)

A base film made of synthetic resin;
A gas barrier layer laminated on at least one surface of the base film;
A planarization layer laminated on the outer surface of the gas barrier layer,
The gas barrier layer is formed of an inorganic oxide or an inorganic nitride;
The planarization layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof, and
A high barrier sheet in which the gas barrier layer and the planarization layer are repeatedly laminated in the same order a plurality of times . 2. The high barrier property according to claim 1, wherein one or two or more selected from the group consisting of silicon oxide, silicon nitride, and aluminum oxide are used as the inorganic oxide or inorganic nitride. Sheet. The high barrier sheet according to claim 1 or 2 , wherein the gas barrier layer is formed by physical vapor deposition or chemical vapor deposition. The high barrier sheet according to claim 3 , wherein a sputtering method is used as the physical vapor deposition method. The high barrier sheet according to claim 3 , wherein a plasma chemical vapor deposition method is used as the chemical vapor deposition method. The high barrier sheet according to any one of claims 1 to 5, wherein the composition contains a metal alkoxide having a functional group containing at least one of nitrogen, oxygen, sulfur, and halogen. The high barrier sheet according to any one of claims 1 to 6, wherein the composition contains a polymer that is soluble in an organic solvent and / or water that can be used in a sol-gel method . The high barrier sheet according to any one of claims 1 to 7, wherein in the formation of the flattening layer by the sol-gel method, the composition is irradiated with ultraviolet rays while being heated. The high barrier property sheet according to any one of claims 1 to 8, wherein a surface treatment for promoting adhesion to the gas barrier layer is applied to the gas barrier layer lamination surface of the base film. The high-barrier sheet according to claim 9 , wherein low-temperature plasma treatment and / or anchor coat treatment is used as the surface treatment.

Images