JP4310783B2 - 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.

  Moreover, the surface of the base film 51 made of synthetic resin in the conventional high barrier sheet has a predetermined surface roughness, and dust, an anti-slip agent, or the like is attached to the surface. Due to the surface properties of the base film 51, the occurrence of defects in the deposited film of the gas barrier layer 52 is increased, leading to a decrease in gas barrier properties of the conventional high barrier sheet.

  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 high barrier sheet of the present invention made to solve the above problems is
A base film made of synthetic resin;
One planarization layer laminated on at least one surface of the base film;
A gas barrier layer laminated on the outer surface of the one planarization layer;
Another planarization layer laminated on the outer surface of the gas barrier layer,
The one planarizing layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof, or a silicone resin having an outer surface subjected to oxygen plasma treatment,
The gas barrier layer is formed of an inorganic oxide or an inorganic nitride;
The other planarizing layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof,
In the formation of the one flattening layer by the sol-gel method, the composition is irradiated with ultraviolet rays while being heated.

  In the high barrier sheet, since one flattening layer is laminated on the base film, and the gas barrier layer is laminated on the outer surface of the flattening layer, the surface roughness of the base film by the one flattening layer. As a result of being coated with dust, an anti-slip agent or the like adhering to the surface of the base film, the smoothness of the interface where the gas barrier layers are laminated can be promoted. Therefore, the high-barrier sheet promotes the denseness of the gas barrier layer and reduces the occurrence of defects such as pinholes, crystal grain boundaries, and cracks in the gas barrier layer. improves.

  In addition, since the high barrier sheet has another planarization layer laminated on the outer surface of the gas barrier layer, even if defects such as pinholes, crystal grain boundaries, cracks, etc. occur in the gas barrier layer, the defects are not detected. It is sealed by another planarizing layer and the gas barrier layer is protected by the other planarizing layer. 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 other planarization layer may be laminated by repeating a plurality of times in the same order. Thus, the gas barrier property of the high barrier sheet can be remarkably improved by repeatedly laminating the gas barrier layer and the other planarizing layer in the same order a plurality of times. The other planarization layer laminated between the pair of gas barrier layers is caused by the smoothness of the interface with respect to the gas barrier layer laminated on the outer surface side in addition to the defect sealing function for the gas barrier layer on the inner surface side described above. The denseness promoting function of the gas barrier layer can also be exhibited.

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 planarizing layer may be 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 such a composition containing a metal alkoxide and / or a hydrolyzate thereof, the above-described gas barrier layer laminated on the flattening layer outer surface has a function of promoting denseness and the inner surface of the flattening layer. A planarization layer having a defect sealing function for the gas barrier layer to be laminated can be easily and reliably formed. 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, and the adhesion between the base film and the one planarizing layer can be improved.

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 (particularly, , Gas barrier properties at high temperatures) can be further enhanced.

In the formation of one planarization layer by the sol-gel method, ultraviolet irradiation is applied to the composition together with heating, and in the formation of the other planarization layer, ultraviolet irradiation is applied to the composition together with heating. It should be given. 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, so that the film properties and the adhesion of the planarization layer are increased. Will improve. Therefore, the high barrier sheet has higher gas barrier properties, heat resistance, transparency, and the like.

  The one planarizing layer may be formed of a silicone resin. Thus, even if one flattening layer is formed from a silicone resin, the above-described gas barrier layer can be provided with a denseness promoting function and a defect sealing function, and further, the one flattening layer can be promoted with a gas barrier property. it can.

  Oxygen plasma treatment may be performed on the outer surface (gas barrier layer lamination surface) of one planarization layer formed from the silicone resin. In this way, by performing oxygen plasma treatment on the outer surface of the one planarizing layer made of silicone resin, the surface of the one planarizing layer is activated, and the function of promoting the denseness of the gas barrier layer is improved. Therefore, the high barrier sheet has good adhesion between one planarization layer and a gas barrier layer (particularly, a gas barrier layer made of silicon oxide), and the gas barrier property of the gas barrier layer is further enhanced.

  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 of FIG. 1 includes a base film 1 made of synthetic resin, a flattening layer 2 laminated on one surface of the base film 1, and an outer surface of the flattening layer 2. A gas barrier layer 3 to be laminated and another planarizing layer 4 to be laminated on the outer surface of the gas barrier layer 3 are provided. The high-barrier sheet has high gas barrier properties mainly due to the gas barrier layer 3 and, in addition, 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, it has high heat resistance, strength, weather resistance, durability, gas barrier properties against water vapor, etc., withstands vapor deposition conditions of the gas barrier layer 3, and has excellent tight adhesion with one planarizing layer 2. Polyester resins, fluorine resins and cyclic polyolefin resins are preferred.

  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 the thickness (average thickness) of base 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, inconveniences such as curl are likely to occur during vapor deposition for forming the gas barrier layer 3 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.

  One planarization layer 2 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 coating 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 2. It is possible to improve the film physical properties of the planarization layer 2 and thus the gas barrier property, and in addition, the temperature dependence of the gas barrier property of the planarization layer 2 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, vinyltrichlorosilane, and β- (3,4-epoxycyclohexyl) ethyl. Trimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N- β (aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-ureidopropyltriethoxysilane, bis (β-hydroxyethyl) -γ-aminopropyltriethoxysilane, γ-aminopropylsilicone, etc. One of these metal alkoxides It may be used or two or more.

  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) within the above range, a polysiloxane structure that contributes to gas barrier properties can be expressed in the planarization layer 2.

  A solvent-soluble polymer may be contained in the composition. By forming the planarization layer 2 by a sol-gel method using a composition containing such a solvent-soluble polymer and a metal alkoxide, the film physical properties of the planarization layer 2 are improved, and the gas barrier property of the planarization layer 2 ( 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 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, and an organic product produced by hydrolysis polymerization of the metal alkoxide. 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 planarizing layer 2, various kinds of plasticizers, antioxidants, ultraviolet absorbers, flame retardants, antistatic agents, surfactants, fillers, colorants and the like may be used as necessary. These additives may be appropriately blended.

  Next, a method for forming the planarizing layer 2 will be described. The planarization layer 2 can be 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 composition. The surface of the base film 1 is coated by a coating method, then heated and dried, and further subjected to an aging treatment or the like, thereby forming a planarized layer 2 that 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 2, 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 2 has significantly fewer defects. Excellent physical properties and improved adhesion between the planarizing layer 2 and the base film 1. Therefore, the gas barrier property of the planarization layer 2 is further improved.

The gas barrier layer 3 is formed by depositing an inorganic oxide or an inorganic nitride on the outer surface of one planarizing layer 2 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 and transparency are preferable, and one or more selected from these groups are preferable. 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) using a metal oxide as a raw material, heating this, evaporating and vapor-depositing on the planarizing layer 2, (b) using a metal or metal oxide 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 2, and (c) a plasma-assisted reactive deposition method in which a reaction such as oxidation is further supported 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 3 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 an inorganic oxide or nitride vapor-deposited thin film such as silicon oxide on the planarizing layer 2. 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 3 may have a single layer structure or a multilayer structure of two or more layers. As described above, the gas barrier layer 3 has a multi-layer structure, thereby reducing the deterioration of the base film 1 by reducing the thermal load applied during vapor deposition, and further improving the adhesion between the planarizing layer 2 and the gas barrier layer 3. 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 3, and the like.

  As a minimum of the thickness (average thickness) of gas barrier layer 3, 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 3 is preferably 200 nm, and particularly preferably 100 nm. If the thickness of the gas barrier layer 3 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 3 exceeds the above upper limit, the flexibility is lowered and defects such as cracks are likely to occur in the gas barrier layer 3.

  The other planarization layer 4 is laminated on the outer surface of the gas barrier layer 3 and is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof in the same manner as the one planarization layer 2 described above. It is formed.

  Even if the surface of the base film 1 (the gas barrier layer 3 laminated surface) has a predetermined surface roughness, dust, anti-slip agent or the like attached thereto, the high barrier sheet has the base film 1 by the flattening layer 2. The smoothness of the interface where the gas barrier layer 3 is laminated is promoted. Therefore, the high barrier sheet promotes the growth of a dense and uniform deposited film such as an inorganic oxide, and reduces the occurrence of defects such as pinholes, crystal grain boundaries, and cracks in the gas barrier layer 3. In the high barrier sheet, even if defects such as pinholes, crystal grain boundaries, and cracks occur in the gas barrier layer 3, the defects are blocked by another planarizing layer 4, and the other planarizing layer 4 Thus, the gas barrier layer 3 is protected. Furthermore, in addition to the high gas barrier property of the gas barrier layer 3, the pair of planarization layers 2 and 4 laminated on both surfaces of the gas barrier layer 3 contribute to the improvement of the gas barrier property. 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, one flattening layer 2 laminated on one surface of the base film 1, and an outer surface of the one flattening layer 2. The gas barrier layer 3 to be laminated, the other planarizing layer 4 laminated on the outer surface of the gas barrier layer 3, the gas barrier layer 3 laminated on the outer surface of the other planarizing layer 4, and the outer surface of the gas barrier layer 3 And another planarizing layer 4 laminated on the substrate. That is, in the high barrier sheet, the gas barrier layer 3 and the other planarization layer 4 are repeatedly laminated in this order twice on the outer surface of the laminate of the base film 1 and the one planarization layer 2. The base film 1, the one flattening layer 2, the gas barrier layer 3 and the other flattening layer 4 in the high barrier sheet are the same as the high barrier sheet of FIG. Description is omitted.

  Since the high barrier sheet has two gas barrier layers 3 having high gas barrier properties and three planarization layers 2 and 4 having predetermined gas barrier properties, the sheet has very high gas barrier properties, and It has various properties such as high transparency, heat resistance and flexibility. The other planarization layer 4 laminated between the pair of gas barrier layers 3 has an interface with respect to the gas barrier layer 3 laminated on the outer surface side in addition to the above-described defect sealing function for the gas barrier layer 3 on the inner surface side. A function of promoting the growth of a dense and uniform deposited film due to smoothness can also be exhibited.

  The high barrier sheet of the present invention is not limited to the above-described embodiment. For example, a high barrier sheet having a structure in which the gas barrier layer 3 and another planarizing layer 4 are repeatedly laminated three or more times in this order is also possible. It is. By laminating three or more gas barrier layers 3 in this manner, various characteristics such as gas barrier properties, weather resistance, and durability can be significantly improved.

  Moreover, the one planarization layer 2 is not limited to being formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof, and may be formed from, for example, a silicone resin. Good. Thus, even if one flattening layer 2 is formed from a silicone resin, the above-described gas barrier layer 3 can have a denseness promoting function and a defect sealing function, and the one flattening layer 2 can have a gas barrier property. be able to.

  Examples of the silicone resin building blocks include polysiloxanes including dimethylsiloxane, diethylsiloxane, diphenylsiloxane, methylvinylsiloxane, ethylvinylsiloxane, phenylvinylsiloxane, ethylmethylsiloxane, methylphenylsiloxane, ethylphenylsiloxane, and the like. Polydimethylsiloxane having a good smoothness promoting function is preferable.

  When one planarization layer 2 is formed from a silicone resin, an oxygen plasma treatment may be performed on the outer surface of the one planarization layer 2 (the surface on which the gas barrier layer 3 is laminated). In this way, by performing oxygen plasma treatment on the outer surface of the flattening layer 2 made of silicone resin, the methyl group on the surface of the flattening layer 2 can be converted into a hydroxyl group, and in particular with a gas barrier layer made of silicon oxide. Adhesiveness can be improved, and a vapor-deposited film of silicon oxide can be grown densely and uniformly. As a result, the gas barrier property of the high barrier sheet is further enhanced.

  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]
Using a base film made of transparent polyethylene terephthalate having a thickness of 25 μm, 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 tertiary amine, and γ-glycidoxypropyltrimethoxy One composition for flattening layer containing 3.4 parts by mass of silane was coated on one surface of the substrate film by 1.0 g / m ² (dry state) using a gravure roll coating method, One planarization layer was laminated by heat treatment at 120 ° C. for 1 minute. Next, a gas barrier layer having a thickness of 100 nm was laminated on the outer surface of the one planarizing layer by vapor-depositing silicon oxide (oxidation degree X = about 1.8) by a sputtering method. Further, another composition for a flattening layer containing 5.2 parts by mass of tetraethoxysilane, 1.1 parts by mass of methyltriethoxysilane, 3 parts by mass of isopropyl alcohol, and 0.03 parts by mass of a tertiary amine is added to the gas barrier layer. The outer surface was coated with 1.0 g / m ² (dry state) using a gravure roll coating method, and heat treatment was performed at 100 ° C. for 3 minutes to laminate another planarizing layer. The high barrier sheet of Example 1 was obtained through this process.

[Example 2]
Example 2 in the same manner as in Example 1 except that the content of the tetraethoxysilane was 20 parts by mass and 14 parts by mass of γ-aminopropyltrimethoxysilane was contained in the one flattening layer composition. The high barrier property 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 one flattening layer composition.

[Example 4]
In the step of forming the one flattening layer, an example was carried out in the same manner as in Example 1 except that the heat treatment temperature was set to 90 ° C. and the coating surface was irradiated with ultraviolet rays having a wavelength of 210 nm for 10 minutes during the heat treatment. 4 high barrier property 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 one planarizing layer was formed from polydimethylsiloxane and the outer surface of the one planarizing layer was subjected to oxygen plasma treatment.

[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 and the gas barrier layer was laminated directly on one surface of the base film.

[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, Examples 1 to 9 in which a pair of planarization layers are laminated on both sides of the gas barrier layer as compared with the high barrier sheet of the comparative example in which the gas barrier layer is directly laminated on the base film. This high 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. Furthermore, the high barrier sheets of Examples 2, 3 and 4 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 One planarization layer 3 Gas barrier layer 4 Other planarization layers

Claims (8)

A base film made of synthetic resin;
One planarization layer laminated on at least one surface of the base film;
A gas barrier layer laminated on the outer surface of the one planarization layer;
Another planarization layer laminated on the outer surface of the gas barrier layer,
The one planarizing layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof, or a silicone resin having an outer surface subjected to oxygen plasma treatment,
The gas barrier layer is formed of an inorganic oxide or an inorganic nitride;
The other planarizing layer is formed by a sol-gel method using a composition containing a metal alkoxide and / or a hydrolyzate thereof,
A high-barrier sheet in which, in the formation of the one flattening layer by a sol-gel method, ultraviolet irradiation is applied to the composition together with heating .   The high-barrier sheet according to claim 1, wherein the gas barrier layer and another planarizing layer are repeatedly laminated in the same order a plurality of times. As the inorganic oxide or an inorganic nitride, silicon oxide, according to the silicon nitride and one or claim 1 2 or more that have been used or Claim 2 selected from the group consisting of aluminum oxide High barrier sheet. The high barrier property sheet according to any one of claims 1 to 3 , wherein the gas barrier layer is formed by a physical vapor deposition method or a chemical vapor deposition method. The high barrier sheet according to claim 4 , wherein a sputtering method is used as the physical vapor deposition method. The high barrier property sheet according to claim 4 , wherein a plasma chemical vapor deposition method is used as the chemical vapor deposition method. The high barrier property sheet according to any one of claims 1 to 6, 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 7, wherein the composition contains an organic solvent that can be used in a sol-gel method and / or a polymer that is soluble in water .

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