JP4475066B2 - Gas barrier laminate - Google Patents

Description

  The present invention relates to a gas barrier laminate, and in particular, is excellent in printability (particularly gradation printability), excellent in gas barrier properties even when printing is performed, and is a plastic substrate when subjected to hydrothermal treatment. The present invention relates to a gas barrier laminate excellent in adhesion and gas barrier properties between a material and an inorganic thin film.

  Conventionally, a gas barrier laminate in which an inorganic thin film such as aluminum oxide, magnesium oxide, silicon oxide or the like is formed on a surface of a plastic by a vapor deposition method, a sputtering method, a CVD method, or an ion plating method, It is widely used in packaging applications for articles that require blocking of various gases such as oxygen, and packaging applications for preventing alterations in foods, industrial products and pharmaceuticals. These gas barrier laminates have recently been used as components of transparent conductive sheets used in liquid crystal display elements, solar cells, electromagnetic wave shields, touch panels, EL substrates, color filters, etc., in addition to packaging applications. . Furthermore, the gas barrier laminate generally has good printability due to good wettability of the inorganic thin film, and is widely used as a printing packaging material.

  In order to improve the barrier property of the inorganic thin film, a method of performing various treatments on the thin film surface has been devised for the gas barrier laminate. For example, it is known that a gas barrier property is improved by using a silicon oxide vapor-deposited film as an inorganic thin film, absorbing moisture in the vapor-deposited film, and performing heat treatment (see, for example, Patent Document 1).

  However, the gas barrier laminate produced by the above-described method has a defect in the inorganic thin film when the inorganic thin film is rubbed in the subsequent bonding process or printing process or when the laminate is folded in the bag making process. This causes a problem that the gas barrier property is lowered. In particular, when printing is performed using white ink containing titanium oxide as a pigment, there is a high possibility that defects will occur in the inorganic thin film, and the gas barrier properties may be greatly reduced. In particular, when the inorganic thin film is damaged by printing, there is a problem that the gas barrier property is greatly lowered by the subsequent hot water treatment.

  A method of providing a transparent primer layer made of a resin having a glass transition temperature of 40 ° C. or higher on the surface of the inorganic thin film layer in order to prevent damage to the inorganic thin film due to the above processing steps (for example, see Patent Document 2), and a method of providing an aqueous anchor layer (For example, refer to Patent Document 3), a method of providing a layer formed of an aqueous resin or aqueous emulsion containing silicon oxide (for example, refer to Patent Document 4), a polyester resin having a glass transition temperature of 60 to 80 ° C. and a molecular weight of 10,000 to 20,000, A method of providing a primer layer made of a polyurethane resin or a nitrocellulose resin (see, for example, Patent Document 5), a method of providing a coating layer made of an organic polymer and an inorganic fine powder (see, for example, Patent Document 6), and urethane and / or A method of providing a resin coat layer such as vinyl chloride-vinyl acetate copolymer (for example, special The literature reference 7), a method of preventing damage to the inorganic thin film is adopted.

  However, when the gas barrier laminate obtained by applying a transparent primer to the surface of the inorganic thin film is retorted, the inorganic thin film is damaged by the stress during retorting and the gas barrier property is lowered. Moreover, although the method of apply | coating the coating agent which consists of a polyfunctional isocyanate compound and polyester polyol to the surface of an inorganic thin film is also examined, it was difficult to fully stabilize the oxygen barrier property after a retort.

JP-A-2-299826 JP-A-5-269914 JP-A-5-309777 JP-A-5-9317 JP 7-137192 A Japanese Patent Laid-Open No. 10-71663 JP 2001-270026 JP

  The present invention has been made in view of the above circumstances, and its purpose is excellent in printability (particularly gradation printability), excellent in gas barrier properties even when printing is performed, and hot water treatment. It is to provide a gas barrier laminate excellent in adhesion and gas barrier properties between a plastic substrate and an inorganic thin film when subjected to.

  In order to achieve the above object, the present inventors have conducted intensive studies, and as a result, provided a coating layer having a specific hardness on the surface of the inorganic thin film and / or carbon constituting the surface of the coating layer. By providing a coating layer in which the ratio of the number of carbons derived from carboxyl groups to the number of the coating layer is in a specific range, damage to the inorganic thin film by printing ink is prevented, and stress relaxation and binding properties of the coating layer are reduced. As a result of the improvement, it was found that the barrier property of the inorganic thin film can be maintained even after the hot water treatment, and the present invention has been completed.

That is, the first gist of the present invention is that a plastic substrate (A), an inorganic thin film (B) formed on at least one surface of the plastic substrate (A), and a surface of the inorganic thin film (B) are formed. A gas barrier laminate comprising the applied coating layer (C), the hardness of the coating layer (C) measured by the nanoindent method in the atmosphere at 23 ° C. is 0.1 to 0.5 GPa, Oxygen permeability of gas barrier laminate after subjecting gas barrier laminate made by laminating unstretched polypropylene film of 60 μm thickness on coating layer (C) to hydrothermal treatment at 120 ° C for 30 minutes Ri der There 50fmol ^/ m 2 ^/ s ^/ Pa or less, the resin components forming the coating layer (C) is, (i) a combination of polyester resin and urethane resin, (ii) an acrylic resin and urethane resin And oxazoline group The combination of fat, or consists in gas barrier laminate according to (iii) alkoxysilyl group-containing urethane resin der wherein Rukoto.

The second gist of the present invention is a plastic substrate (A), an inorganic thin film (B) formed on at least one surface of the plastic substrate (A), and formed on the surface of the inorganic thin film (B). A gas barrier laminate comprising a coating layer (C), the coating layer (C) having a hardness of 0.03 to 0.5 GPa measured by a nanoindent method in water at 23 ° C. (C) A gas barrier laminate obtained by laminating an unstretched polypropylene film having a thickness of 60 μm on top of the gas barrier laminate after hydrothermal treatment at 120 ° C. for 30 minutes has an oxygen permeability of 50 fmol / m 2 ^{/ s /} Pa Ri der hereinafter resin component forming the coating layer (C) is, (i) a combination of polyester resin and urethane resin, (ii) an acrylic resin and a urethane resin and an oxazoline group Resin combination Or consists in gas barrier laminate according to (iii) alkoxysilyl group-containing urethane resin der wherein Rukoto.

The third gist of the present invention is a plastic substrate (A), an inorganic thin film (B) formed on at least one surface of the plastic substrate (A), and formed on the surface of the inorganic thin film (B). A gas barrier laminate comprising a coating layer (C), wherein the ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is 0.005 to 0.1. The gas barrier laminate obtained by subjecting a gas barrier laminate formed by laminating an unstretched polypropylene film having a thickness of 60 μm on the coating layer (C) to hydrothermal treatment at 120 ° C. for 30 minutes. oxygen permeability Ri der less ^{50fmol / m 2 / s / Pa} , the resin component forming the coating layer (C) is, (i) a polyester resin and urethane resin combination, and (ii) an acrylic resin Urethane resin and oxazoline group-containing tree Combinations, or consists in gas barrier laminate according to (iii) alkoxysilyl group-containing urethane resin der wherein Rukoto.

  It exists in the gas-barrier laminated body which heat-processed 60 degreeC or more to said gas-barrier laminated body.

  The gas barrier laminate of the present invention is excellent in printability (especially gradation printability), excellent in gas barrier properties even when printing is performed, and is made of a plastic base material and inorganic when subjected to hydrothermal treatment. Excellent adhesion to the thin film and gas barrier properties.

  Hereinafter, the present invention will be described in detail. The plastic constituting the plastic substrate (A) used in the present invention is not particularly limited as long as it can be used for ordinary packaging materials, such as ethylene, propylene, butene and other homopolymers or copolymers. Amorphous polyolefin such as polyolefin and cyclic polyolefin, polyester such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polyamide such as nylon 6, nylon 66, nylon 12 and copolymer nylon, ethylene-vinyl alcohol copolymer (ethylene -Partially hydrolyzed vinyl acetate copolymer (EVOH), polyimide, polyetherimide, polysulfone, polyethersulfone, polyetheretherketone, polycarbonate (PC), polyvinyl butyral, polyarylate, fluororesin, acrylate DOO resins, such as a biodegradable resin.

  Biodegradable resins include starch / polycaprolactone (eg “Master Bee Z” sold by Nippon Gohsei Co., Ltd., polycaprolactone (eg “Selgrund” manufactured by Daicel Chemical Industries)), polyethylene succinate (“Lunare SE” manufactured by Nippon Shokubai Co., Ltd.), Polybutylene succinate (for example, “Bionore 1001” manufactured by Showa Polymer Co., Ltd.), polybutylene succinate adipate (for example, “Bionore 3001” manufactured by Showa Polymer Co., Ltd.), polyester carbonate (for example, “Yupak” manufactured by Mitsubishi Gas Chemical Company, Inc.) , Aliphatic polyesters (succinic acid, “GS-Pla” manufactured by Mitsubishi Chemical Corporation), aromatic polyesters (adipic acid) (for example, “Ecoflex” manufactured by BASF), etc. Except for “B”, it is a chemically synthesized resin. Biodegradable resins using natural products such as lactic acid (“LACEA” manufactured by Mitsui Chemicals, Inc., cellulose acetate (for example, “Cell Green PCA” manufactured by Daicel Chemical), and modified starch (“Corn Pol” sold by Nippon Corn Starch) Etc.

  Among the above resins, polyester, polyamide, polyolefin, ethylene-vinyl alcohol copolymer and biodegradable resin are preferable.

  The plastic substrate (A) in the present invention is formed by using the above-mentioned raw materials, and may be an unstretched substrate or a stretched substrate. Moreover, you may laminate | stack with the other plastic base material. Such a plastic substrate (A) is preferably a substrate formed into a film from the viewpoint of thin film formation productivity, and can be produced by a conventionally known general method. For example, an unstretched film that is substantially amorphous and unoriented can be produced by supplying a raw material resin to an extruder, melting it, extruding it with an annular die or T-die, and rapidly cooling it. This unstretched film is stretched in the longitudinal direction and / or the transverse direction of the film by a conventionally known general method such as uniaxial stretching, tenter-type sequential biaxial stretching, tenter-type simultaneous biaxial stretching, and tubular-type simultaneous biaxial stretching. By stretching, a film stretched at least in a uniaxial direction can be produced.

  The thickness of the film as the plastic substrate (A) is determined according to the mechanical strength, flexibility, transparency, and application as the substrate of the laminated structure of the present invention, but is usually 5 to 500 μm, Preferably, it is selected in the range of 10 to 200 μm. Moreover, there is no restriction | limiting in particular in the width | variety and length of a film, According to a use, it can select suitably.

  An inorganic thin film (B) is formed on the plastic substrate (A), but an anchor coat layer is formed on the plastic substrate (A) in order to improve the adhesion between the inorganic thin film (B) and the plastic substrate (A). Is preferably provided. The anchor coat layer is usually formed by applying a coating solution containing an anchor coating agent by in-line coating or offline coating. As anchor coating agents, solvent-soluble or water-soluble polyester resins, isocyanate resins, urethane resins, acrylic resins, vinyl alcohol resins, ethylene vinyl alcohol resins, vinyl modified resins, epoxy resins, oxazoline group-containing resins, modified styrene resins, modified Silicon resins, copolymer resins thereof, alkyl titanates and the like are exemplified, and these may be used in combination of two or more. Among them, the anchor coat layer is formed of at least one resin selected from the group consisting of polyester resins, urethane resins, acrylic resins, alkoxysilyl group-containing resins, oxazoline group-containing resins, and copolymer resins thereof. It is preferable.

  The anchor coat layer has a thickness of usually 0.005 to 5 μm, preferably 0.01 to 1 μm. When the thickness of the anchor coat layer exceeds 5 μm, the slipping property is deteriorated, and it becomes easy to peel off from the base film or sheet due to the internal stress of the anchor coat layer, and when the thickness is less than 0.005 μm, the thickness of the anchor coat layer is It may not be uniform. Moreover, in order to improve the applicability | paintability and adhesiveness of the coating liquid containing the anchor coat agent to a film, you may give a chemical process, an electrical discharge process, etc. to the surface of a base film before application | coating.

  Examples of inorganic substances constituting the inorganic thin film (B) formed on the plastic substrate (A) include silicon, aluminum, magnesium, zinc, tin, nickel, titanium, and carbon, and oxides, carbides, and nitrides thereof. And a mixture thereof, preferably silicon oxide, aluminum oxide, diamond-like carbon. In particular, silicon oxide is particularly preferable because the effect of the heat treatment in the present invention is significant, transparency is good, and high gas barrier properties can be stably maintained.

  There is no restriction | limiting in particular as a formation method of an inorganic thin film (B), Although a vapor deposition method, a coating method, etc. can be employ | adopted, A vapor deposition method is preferable at the point that a uniform thin film with high gas barrier property is obtained. As the vapor deposition method, a physical vapor deposition method such as vacuum vapor deposition, ion plating or sputtering, and a chemical vapor deposition method such as CVD can be employed. The thickness of the inorganic thin film (B) is usually 0.1 to 500 nm, preferably 0.5 to 40 nm. When the thickness of the inorganic thin film (B) is less than 0.1 nm, it is difficult to obtain a sufficient gas barrier property, and when it exceeds 500 nm, the inorganic thin film (B) is cracked or peeled, or the transparency is deteriorated.

  The coating layer (C) provided on the surface of the inorganic thin film (B) is (1) the hardness of the coating layer (C) measured by the nanoindent method in the atmosphere at 23 ° C. is 0.1 to 0.5 GPa, Preferably 0.2 to 0.4 GPa, (2) The hardness of the coating layer (C) measured by the nanoindent method in water at 23 ° C. is 0.03 to 0.5 GPa, preferably 0.1 to 0.4. Or (3) the ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is 0.005 to 0.1, preferably 0.008 to 0.05. It has one or more characteristics.

  The nano indentation method (nano indentation hardness measurement method) is a method of measuring indentation hardness at the nano level by adding an indentation hardness measurement module (configured with a transducer and an indenter) to an AFM (atomic force microscope). It is. The measurement is performed by applying a load controlled by a transducer to the indenter and detecting the indentation depth of the sample at that time. Details of the measurement method will be described in Examples. The ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is Polym. Sci. , Part A, Vol. 26, p. 559-572 (1988) and Japanese Patent No. 3139522. Details of the measurement method will be described in Examples.

  If the hardness of the coating layer (C) measured by the nanoindent method in the air at 23 ° C. is too large, the coating layer (C) cannot follow the dimensional change of the entire laminate during the hot water treatment. The barrier property after the hot water treatment tends to deteriorate, and if the hardness is too small, the print gradation property tends to deteriorate.

  When the hardness of the coating layer (C) measured by the nanoindent method in water at 23 ° C. is too large, the coating layer (C) cannot follow the dimensional change of the entire laminate during the hydrothermal treatment, The barrier property after the hot water treatment tends to be poor, and if the hardness is too small, the adhesiveness during the hot water treatment tends to be lowered.

  In addition, even if the hardness of the coating layer (C) measured by the nano-indent method in the air at 23 ° C. is out of the above range, the nano-indent method in the water at 23 ° C. If the hardness of the coating layer (C) measured by the above is within the above range, the effect of the present invention can be achieved by moisture absorption during retort.

  When the ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is too small, the adhesion strength of each layer in water tends to decrease, and the above ratio is large. When too much, it is easy to hydrolyze in the coating-agent liquid prepared in order to form a coating layer (C), and there exists a tendency for various physical properties of the formed coating layer (C) to become unstable.

  Examples of the resin for forming the coating layer (C) include polyester resins, polyurethane resins, acrylic resins, alkoxysilyl group-containing resins, oxazoline resins, epoxy resins, melamine resins, and the like. May be contained. Especially, it is preferable to form from 1 or more types of resin selected from the group of polyester-type resin, urethane-type resin, acrylic resin, alkoxysilyl group containing resin, oxazoline group containing resin, and these copolymer resins. In order to adjust the hardness of the coating layer (C) in the air or water within the above range, a block and / or graft copolymer may be used, or two or more different types of resins or the same resin may be used. It is preferable to use a mixture of resins having different molecular weights or molecular weight distributions of more than one species.

  Examples of the polyvalent carboxylic acid component constituting the polyester resin include terephthalic acid, isophthalic acid, adipic acid, sebacic acid, azelaic acid, orthophthalic acid, diphenyldicarboxylic acid, and dimethylphthalic acid. Examples include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, diethylene glycol, neopentyl glycol, dipropylene glycol, 1,6-hexanediol, and bisphenol A. The

  The molecular weight of the polyester resin is usually 3000 to 15000, preferably 4000 to 13000. When the molecular weight of the polyester resin is less than 3000, the performance as a protective layer may not be obtained because the coating film becomes brittle. On the other hand, when the molecular weight is more than 15000, even if polyisocyanate or the like is used for crosslinking, the number of crosslinking points is small and the crosslinking density does not increase, so that it may dissolve or swell in the printing ink and deteriorate the printing appearance.

  The glass transition temperature (Tg) of the polyester resin is usually from 55 to 100 ° C, preferably from 60 to 95 ° C. When the glass transition temperature (Tg) of the polyester-based resin is less than 55 ° C., the coating layer (C) shrinks due to poor thermal stability, gas barrier properties are reduced, and blocking occurs during storage, resulting in gas barrier properties. Decrease or roughening of the coated surface may occur. On the other hand, when glass transition temperature (Tg) exceeds 100 degreeC, the adhesiveness of a coating layer (C) and an inorganic thin film (B) may fall.

  The acid value of the polyester resin is usually 1 to 100 mgKOH / g, preferably 3 to 80 mgKOH / g. When the acid value is less than 3 mgKOH / g, there are few crosslinking points and the crosslinking density does not increase, so that it dissolves or swells in the printing ink and gas barrier properties may be lowered. On the other hand, when the acid value exceeds 80 mgKOH / g, there are many crosslinking points, the crosslinking density becomes too high, the coating layer (C) becomes hard and does not stretch, and the curing stress of the coating layer (C) increases. For this reason, the gas barrier property is lowered, and the adhesion between the coating layer (C) and the inorganic thin film (B) may be lowered.

  When the polyester resin is produced, the above-mentioned molecular weight, glass transition temperature and acid value are adjusted by reacting the above-mentioned polycarboxylic acid component with the polyhydric alcohol component in an excessive amount of COOH groups relative to the amount of OH groups. The polyester which has can be obtained. For example, by mixing and reacting phthalic acid, terephthalic acid, ethylene glycol and neopentyl glycol, a polyester having a weight average molecular weight of 8000, an acid value of 16 mgKOH / g, and a glass transition temperature of 62 ° C. is obtained.

  Carbon derived from carboxyl groups relative to the number of carbons constituting the surface of the coating layer (C) by using a polyester resin having many carboxyl groups at the molecular ends and / or side chains as a coating agent The number ratio can be adjusted to 0.005 or more. Resins having a large amount of carboxylic acid at the terminal and / or side chain are, for example, polyester resins such as JP-A-54-46294, JP-A-60-209073, JP-A-62-240318, JP-A-53. -28828, JP-A-53-26829, JP-A-53-98336, JP-A-56-116718, JP-A-61-124684, etc. It can be produced by copolymerizing an acid.

  Examples of the polyvalent carboxylic acid include trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, 4-methylcyclohexene-1,2,3-tricarboxylic acid, trimesic acid, 1,2,3, 4-butanetetracarboxylic acid, 1,2,3,4-pentanetetracarboxylic acid, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, 5- (2,5-dioxotetrahydrofurfuryl) -3 -Methyl-3-cyclohexene-1,2-dicarboxylic acid, 5- (2,5-dioxotetrahydrofurfuryl) -3-cyclohexene-1,2-dicarboxylic acid, cyclopentanetetracarboxylic acid, 2,3,6 , 7-Naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, ethylene glycol bistrimellitate, 2,2 ′, 3 Examples thereof include 3′-diphenyltetracarboxylic acid, thiophene-2,3,4,5-tetracarboxylic acid, and ethylenetetracarboxylic acid, and 5- (2,5-dioxotetrahydrofurfuryl) -3-methyl-3 -Cyclohexene-1,2-dicarboxylic acid is preferred.

  The polyurethane resin is a urethane polymer obtained by reacting an isocyanate compound with a polymer polyol compound, or a urethane polymer obtained by reacting a urethane prepolymer with a chain extender and a reaction terminator, and has an isocyanate group at the terminal. You may have. As the isocyanate compound, known aromatic isocyanates and alicyclic isocyanates can be used. From the viewpoint of food hygiene, isophorone diisocyanate, 1,4-cyclohexane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hydrogenation Preference is given to alicyclic diisocyanate compounds such as xylylene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, and mixtures thereof.

  Examples of the polymer polyol compound to be reacted with the isocyanate compound include known polymer polyols such as polyester polyols and polyether polyols, and mixtures thereof. The polyester polyol is obtained by a dehydration or condensation reaction between a dicarboxylic acid and a diol. Examples of the diester include adipic acid, suberic acid, sebacic acid, isophthalic acid, terephthalic acid, succinic acid, azelaic acid, and diesters of these dimethyl esters. Examples of the diol include ethylene glycol, diethylene glycol, 1, 3 -Propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol and the like are exemplified. Dicarboxylic acids and diols may be used alone or in combination of two or more.

  Polyester urethanes described in JP-A-61-228030 can also be used, and the carboxylic acid components include pendant carboxyl groups such as 2,2-dimethylolpropionic acid and 2,2-dimethylolbutyric acid. The introduction method is described in Japanese Patent Publication No. 52-3438.

  The molecular weight of the polyurethane-based resin is usually 8000 to 30000, preferably 10,000 to 28,000. When the molecular weight of the polyurethane resin is less than 8000, the coating film becomes brittle, so that the performance as the protective layer may not be obtained. On the other hand, when the molecular weight is more than 30000, even if crosslinking is performed using polyisocyanate or the like, the number of crosslinking points is small and the crosslinking density is not increased.

  The glass transition temperature (Tg) of the polyurethane resin is usually 55 ° C. or higher, preferably 55 to 100 ° C. When the glass transition temperature (Tg) of the polyurethane-based resin is less than 55 ° C., the coating layer (C) shrinks due to poor thermal stability, gas barrier properties are reduced, and blocking occurs during storage, resulting in gas barrier properties. Decrease or roughness of the coated surface may occur. On the other hand, when glass transition temperature (Tg) exceeds 100 degreeC, the adhesiveness of a coating layer (C) and an inorganic thin film (B) may fall.

  The acid value of the polyurethane resin is usually 1 to 100 mgKOH / g, preferably 3 to 80 mgKOH / g. When the acid value is less than 1 mg KOH / g, there are few crosslinking points and the crosslinking density does not increase, so that it dissolves or swells in the printing ink and gas barrier properties may be lowered. On the other hand, when the acid value exceeds 100 mgKOH / g, there are many crosslinking points, the crosslinking density becomes too high, the coating layer (C) becomes a hard and non-elongating coating, and the curing stress of the coating layer (C) increases. There is. For this reason, the gas barrier property is lowered, and the adhesion between the coating layer (C) and the inorganic thin film (B) may be lowered.

  The acrylic resin can be obtained by using a monomer having an anionic carboxyl group as a hydrophilic group, as described in “Water-based paint and coating technology” (edited by Technical Information Association). Specifically, it can be obtained by copolymerization of acrylic acid and methyl methacrylate.

  The alkoxysilyl group-containing resin can be obtained by hydrolysis of alkoxysilane as described in JP-A Nos. 2000-63661 and 2000-160067. Specifically, it can be obtained by modifying polyurethane with alkoxysilane in advance or further curing it with a hydrolyzable alkoxysilane by a sol-gel method.

  Examples of the oxazoline-based resin include “Epocross” K-1000, K-2000, WS-500 and WS-700 manufactured by Nippon Shokubai Co., Ltd.

  Examples of the epoxy resin include epoxy polyamide resin, silicon-modified epoxy resin, epoxy resin ester, epoxy phenol resin, and epoxy alkyd resin.

  Examples of the melamine resin include etherified melamine resins and alkylated melamine resins.

  As the crosslinking agent component (curing agent), conventionally known crosslinking agents can be used, and it is particularly preferable to use polyisocyanate. As the polyisocyanate, a polyisocyanate having 3 or more active isocyanate groups in one molecule and having an isocyanate group content of 12% by weight or more (in terms of solid content) is preferably used. Specific examples include aliphatic polyisocyanates such as hexamethylene diisocyanate, xylene diisocyanate, and dicyclohexylmethane diisocyanate, and aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenylene diisocyanate, tolidine diisocyanate, and naphthalene diisocyanate. Examples of the product include “Coronate L” manufactured by Nippon Polyurethane. When using a polyester-type resin and a polyurethane-type resin, the usage-amount of polyisocyanate normally has 0.8 to 1.5 times the sum total of the hydroxyl value equivalent of a polyester-type resin and a polyurethane-type resin. When the amount of polyisocyanate used is less than 0.8 times the total of the hydroxyl group equivalents of the polyester resin and polyurethane resin, the isocyanate group is insufficient and a coating layer (C) having a sufficient crosslinking density cannot be obtained. The solvent resistance of the printing ink to the solvent becomes insufficient, and when it exceeds 1.5 times, the isocyanate group becomes excessive, the formed coating layer (C) becomes hard, and the flexibility is impaired. There is.

  In order to improve adhesion to the inorganic thin film (B), it is preferable to add a silane coupling agent to the coating layer (C), and the amount used is based on the weight of the coating layer (C). Usually, 0.1 to 20% by weight, preferably 0.1 to 3% by weight. As the silane coupling agent, an epoxy group-containing silane coupling agent and an amino group-containing silane coupling agent are preferable. Epoxy group-containing silane coupling agents include epoxy groups such as β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxylane, and γ-glycidoxypropyltrimethoxysilane. A silane coupling agent is exemplified. Examples of amino group-containing silane coupling agents include γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyljetoxylan, N-β (aminoethyl) γ-aminopropyltrimethoxylane, N- β (aminoethyl) γ-aminopropyltriethoxylane is exemplified. These silane coupling agents may be used alone or in combination of two or more. Particularly preferred silane coupling agents are γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltrimethoxysilane.

  The coating agent for forming the coating layer (C) includes aliphatic carbonization such as liquid paraffin, microcrystalline wax, natural paraffin, synthetic paraffin, and polyethylene for the purpose of improving the coating property of the printing ink and the gas barrier property. Fatty acid compounds such as stearic acid, lauric acid, hydroxystearic acid, hydrogenated castor oil; stearic acid amide, oleic acid amide, erucic acid amide, lauric acid amide, palmitic acid amide, behenic acid amide, ricinoleic acid amide, Fatty acid amide compounds such as oxystearic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide, ethylene bis oleic acid amide, ethylene bis behenic acid amide, ethylene bis lauric acid amide; sodium stearate, stearic acid Fatty acid metal salts having 12 to 30 carbon atoms such as calcium and calcium hydroxystearate; fatty acid (partial) ester compounds of polyhydric alcohols such as glycerin fatty acid ester, hydroxystearic acid triglyceride and sorbitan fatty acid ester, butyl stearate, montan wax It is preferable to add at least one selected from the group of fatty acid ester compounds such as long chain ester waxes;

  Among the compounds added to the coating agent, fatty acid compounds, fatty acid amide compounds, and fatty acid ester compounds are preferable, and fatty acid amide compounds are more preferable. The compounding amount of the compound added to the coating agent is usually 0.05 with respect to a total of 100 parts by weight of the polyester resin, polyurethane resin, acrylic resin, alkoxysilyl group-containing resin, oxazoline resin, crosslinker component and the like. -20 parts by weight, preferably 0.1-10 parts by weight. When the addition amount is less than 0.05 parts by weight, the effect of improving the gas barrier property is small, and the printed appearance may be lowered. When the addition amount exceeds 20 parts by weight, the coating layer (C) and the inorganic thin film (B) Adhesion may be reduced.

  For the coating layer (C), known antistatic agents, light blocking agents, ultraviolet absorbers, plasticizers, fillers, colorants, stabilizers, antifoaming agents, crosslinking agents, antiblocking agents, antioxidants, etc. Additives can be added.

  The thickness of a coating layer (C) is 0.05-5 micrometers normally, Preferably it is 0.1-2 micrometers. When the thickness of the coating layer (C) is less than 0.05 μm, the damage of the inorganic thin film (B) due to printing may not be prevented. When the thickness exceeds 5 μm, the transfer property of the printing ink is deteriorated. Sometimes.

  The gas barrier laminate of the present invention can form a printing layer on the coating layer (C), and can further laminate other plastic substrates and paper substrates. As the printing ink for forming the printing layer, aqueous and solvent-based resin-containing printing inks can be used. Here, examples of the resin used in the printing ink include acrylic resins, urethane resins, polyester resins, vinyl chloride resins, vinyl acetate copolymer resins, and mixtures thereof. In addition to printing inks, antistatic agents, light blocking agents, ultraviolet absorbers, plasticizers, lubricants, fillers, colorants, stabilizers, lubricants, antifoaming agents, crosslinking agents, antiblocking agents, antioxidants, etc. Known additives may be added.

  The printing method for providing the printing layer is not particularly limited, and a known printing method such as an offset printing method, a gravure printing method, or a screen printing method can be used. For drying the solvent after printing, known drying methods such as hot air drying, hot roll drying, and infrared drying can be used.

  By using a heat-sealable resin for another plastic base material laminated on the printed layer, heat-seal becomes possible, and it can be used as various containers, particularly as a retort container. That is, a laminate having a configuration of a plastic substrate (A) / inorganic thin film (B) / coating layer (C) / printing layer / other plastic substrate capable of heat sealing (heat sealing layer) (hereinafter referred to as gas barrier) By using another plastic substrate that can be heat-sealed as an inner layer of the container (for retort), a container having excellent gas barrier properties (for retort) can be obtained.

  Moreover, you may laminate | stack at least 1 layer or more of paper or a plastic film between a printing layer and a heat seal layer. As the plastic film, a film made of plastic constituting the plastic substrate (A) can be used. Among these, paper, polyester resin, polyamide resin, and biodegradable resin are preferable from the viewpoint of obtaining sufficient rigidity and strength of the laminate. Especially, by laminating the stretched polyamide resin layer between the printing layer and the heat seal layer, the gas barrier property after the hot water treatment is improved. Therefore, it is preferable that the stretched polyamide resin layer has a 127 ° C. hot water shrinkage of 15% or less. When the hot water shrinkage rate exceeds 15%, the barrier property and adhesion may be deteriorated due to the dimensional change stress in the hot water treatment.

  Examples of the resin capable of heat sealing include polyethylene resins, polypropylene resins, ethylene / vinyl acetate copolymer resins, ionomer resins, EAA resins, EMAA resins, EMA resins, EMMA resins, EEA resins, biodegradable resins, and the like. Is exemplified. As a method for laminating the heat seal layer on the printing layer, a dry laminating method using an adhesive or an extrusion laminating method using an adhesive resin can be employed.

The oxygen permeability of the gas barrier film obtained by laminating the print layer and the heat seal layer on the gas barrier laminate of the present invention is usually 25 fmol / m ² / s / Pa or less, preferably 10 fmol / m ² / s / Pa or less, The lower limit is usually 0.025 fmol / m ² / s / Pa or more. The oxygen permeability of the gas barrier laminate of the present invention (the structure of the plastic substrate (A) / inorganic thin film (B) / coating layer (C)) is 25 fmol / m ² / s / Pa or less as described above. These gas barrier laminates and gas barrier films are in the category of high gas barrier films. The gas barrier laminate and the gas barrier film of the present invention are characterized in that even if they are subjected to a pressurized hot water treatment under a so-called retort treatment, there is little deterioration in gas barrier properties. In particular, the above properties can be effectively imparted by subjecting the gas barrier laminate of the present invention to a heat treatment.

Specifically, the heat treatment is performed after laminating the inorganic thin film (B) on the plastic substrate (A), or the gas barrier laminate of the present invention is obtained by laminating the coating layer (C). Or by laminating another plastic film and / or paper and performing a heat treatment, a gas barrier film can be obtained. The gas barrier laminate after the hydrothermal treatment at 120 ° C. for 30 minutes with respect to the obtained gas barrier film has an oxygen permeability of 50 fmol / m ² / s / Pa or less, preferably 25 fmol / m ² / It is s / Pa or less, more preferably 10 fmol / m ² / s / Pa or less, and particularly preferably 5 fmol / m ² / s / Pa or less.

  The heat treatment is usually performed in a gas barrier film state or a gas barrier laminate state. In the case of the method of heat treatment after forming the gas barrier film, any of the method of performing the heat treatment after the gas barrier film is secondarily processed into a bag, a container, etc., and the method of performing the heat treatment after putting the contents into the secondary processed product Can also be adopted. The conditions for the heat treatment vary depending on the type and thickness of the elements constituting the gas gallium film or gas barrier laminate, but are not particularly limited as long as the method can maintain the required time and the required temperature. For example, a method of storing in an oven or a constant temperature room set to the required temperature, a method of blowing hot air, a method of heating with an infrared heater, a method of irradiating light with a lamp, a direct contact with a hot roll or hot plate Examples thereof include a method of applying heat and a method of irradiating microwaves. Moreover, even if it heat-processes, after cutting a film into the magnitude | size which is easy to handle, it may heat-process with a film roll. Furthermore, if necessary time and temperature can be obtained, a heating device may be incorporated in a part of a film manufacturing apparatus such as a coater or a slitter, and heat treatment may be performed in the manufacturing process.

  The treatment temperature of the heat treatment is not particularly limited as long as it is usually 60 ° C. or higher and the melting point of the plastic substrate (A) and the plastic film to be used, the lower limit is preferably 70 ° C., and the upper limit is usually 200 ° C. ° C, preferably 160 ° C. When the treatment temperature is less than 60 ° C., the treatment time required for the effect of the heat treatment to be manifested becomes extremely long, which is not realistic. The heat treatment time tends to be shorter as the treatment temperature is higher. When the processing temperature is high, the constituent elements of the gas gallium film or the gas barrier laminate may be thermally decomposed and the gas barrier property may be lowered. Therefore, it is preferable to shorten the processing time. As heat treatment conditions, for example, when the treatment temperature is 60 ° C., the treatment time is about 3 days to June, when the treatment temperature is 80 ° C., when the treatment time is about 3 hours to 10 days, and when the treatment temperature is 120 ° C. When the processing temperature is 150 ° C. for a processing time of about 1 hour to 1 day, the processing time is about 3 to 60 minutes. However, these are merely guidelines, and the elements constituting the gas gallium film and the gas barrier laminate. It depends on the type and thickness.

  In the gas barrier laminate and the gas barrier film of the present invention, the adhesion strength between the plastic substrate (A) and the inorganic thin film (B) after the pressurized hot water treatment at 120 ° C. for 30 minutes is related to the presence or absence of the heat treatment. Usually, it is 100 g / 15 mm or more, preferably 200 g / 15 mm or more. In the case where the heat treatment is not performed, the adhesion strength similar to the above is achieved by providing an anchor coat layer. In addition, in the laminate and film in which the print layer and the heat seal layer are provided on the gas barrier laminate of the present invention, the adhesion strength between the print layer and the polyester resin layer after pressurized hot water treatment at 120 ° C. for 30 minutes is Usually, it is 100 g / 15 mm or more, preferably 200 g / 15 mm or more. Further, the shrinkage ratio of the gas barrier laminate and the gas barrier film of the present invention before and after the pressurized hot water treatment is usually 3% or less, preferably 2% or less.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples, unless the summary is exceeded. The measurement methods used in the following examples are described below.

(1) Oxygen permeability (fmol / m ² / s / Pa):
The measurement was performed under conditions of a temperature of 25 ° C. and a relative humidity of 80% using an oxygen permeability measuring device (“OX-TRAN100” manufactured by Modern Control Co., Ltd.) in accordance with ASTM-D3985. The evaluation criteria are shown below.

(2) Adhesion strength:
It consists of a laminate of a plastic substrate / surface modified layer / inorganic thin film / coating layer / printing layer / adhesive layer / other plastic film, and is a strip-like film having a width of 15 mm and a length of 100 mm. At the time of preparation (lamination), a non-existing region of the adhesive layer is formed by interposing a spacer made of release paper in a half of the length direction (that is, a portion having a width of 15 mm and a length of 50 mm). The strip-shaped film formed was used as a sample film. Then, from the region where the adhesive layer is absent, T is peeled from the plastic substrate / surface modified layer / inorganic thin film / coating layer / printing layer side (A side) and the other plastic film side (B side). A mold peel test was performed. That is, in the environment of 23 ° C. and 50% RH, the above-mentioned A side and B side of the autograph (test apparatus according to JIS K 7127, “DSS-100” manufactured by Shimadzu Corporation) and the movable grip Grasp each end, attach at a distance between grips of 60 mm, move the movable grip by 30 mm at a pulling speed of 300 mm / min, and determine the value of the center line from the wavy curve of the tensile load recorded in the strain gauge during this time, The average value in three test pieces was calculated | required. The evaluation criteria are shown below.

(3) Gradation printability:
Using gravure ink as printing ink, “FE-185” manufactured by Fuji Machine Industry Co., Ltd. as a printing machine, printing pattern consisting of five colors of black, indigo, red, yellow and white at a printing speed of 100 m / min ( A halftone dot) was formed on the coating layer, and the gradation printability was evaluated by checking the density reproducibility of the halftone dot of the printed pattern. In addition, the printing pattern to a polyethylene terephthalate (PET) film was used as evaluation criteria. The evaluation criteria are shown below.

(4) Hardness measurement of coating layer (C) by nano-indent method:
Using a scanning probe microscope (“Nanoscope IIIa” manufactured by Digital Instruments) and an ultra-light load thin film hardness tester (“Triboscope system” manufactured by Hystron Inc.) connected to the microscope, measurement was performed under the following conditions.

(5) Ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C):
An X-ray photoelectron spectrometer (“220iKL” manufactured by VG) was used and analyzed under the following conditions.

  The carboxyl group gas phase chemical modification was labeled by esterifying the surface carboxyl group with trifluoroethanol using pyridine and dicyclohexylcarbodiimide as a catalyst in a desiccator in an air atmosphere. A polyacrylic acid film was used as a standard sample and was subjected to gas phase chemical modification treatment simultaneously with the gas barrier laminate. From the standard sample, the reaction rate with trifluoroethanol and the residual rate of the reaction catalyst dicyclohexylcarbodiimide were determined. Polym. Sci. , Part A, Vol. 26, p. The ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the coating layer surface (COOH / C) was calculated by the calculation method described in 559-572 (1988) and Japanese Patent No. 3139522.

Manufacture of anchor coat layer resin A (aqueous acrylic resin):
A mixed monomer composed of 40 parts by weight of ethyl acrylate, 30 parts by weight of methyl methacrylate, 20 parts by weight of methacrylic acid and 10 parts by weight of glycidyl methacrylate was solution polymerized in ethanol. After polymerization, the mixture was heated while adding water to remove ethanol. The aqueous acrylic resin paint was obtained by adjusting the pH to 7.5 with aqueous ammonia.

Production of anchor coat layer resin B (aqueous polyurethane resin):
A polyester polyol was obtained using 664 parts by weight of terephthalic acid, 631 parts by weight of isophthalic acid, 472 parts by weight of 1,4-butanediol and 447 parts by weight of neopentyl glycol. To the obtained polyester polyol, 321 parts by weight of adipic acid and 268 parts by weight of dimethylolpropionic acid were added to obtain a polyester polyol A containing a pendant carboxyl group. 160 parts by weight of hexamethylene diisocyanate was added to 1880 parts by weight of the obtained polyester polyol A to obtain an aqueous polyurethane resin aqueous coating material.

Production of coating resin C (alkoxysilyl group-containing resin):
148 parts by weight of a polyester polyol (Kuraray Co., Ltd., “Kurapol P2010”) and 222 parts by weight of a polyester polyol (Daicel Chemical Industries, Ltd., “Placcel 220”), 102.7 parts by weight of isophoridine diisocyanate and 3-aminoprolyl 27.2 parts by weight of triethoxysilane was added to obtain an alkoxysilyl group-containing polyurethane paint.

Production of vapor-deposited polyethylene terephthalate (PET) film:
Polyethylene terephthalate (PET, melt viscosity = 0.65) was extruded from a T-die at a temperature of 290 ° C. and quenched with a cooling drum to obtain an unstretched PET sheet having a thickness of 150 μm. The obtained PET sheet was stretched 3.5 times in the longitudinal direction at 95 ° C., and then 60% by weight of an oxazoline group-containing polymer (“Epocross WS-500” manufactured by Nippon Shokubai Co., Ltd.), anchor coat layer resin A (aqueous acrylic resin) ) An aqueous solution of mixed resin consisting of 20% by weight and 20% by weight of anchor coat layer resin B (aqueous polyurethane resin) was applied by an in-line coating method, stretched 3.5 times in the transverse direction at 110 ° C, and heat treated at 230 ° C. Thus, a 12.1 μm-thick biaxially stretched PET film having a 0.1 μm-thick anchor coat layer made of the mixed resin was obtained.

Next, on the anchor coat layer, silicon oxide was deposited by a high frequency heating method using a vacuum deposition apparatus to form an inorganic thin film layer made of silicon oxide having a thickness of about 10 nm to obtain a silicon oxide deposited PET film. Similarly, the vapor deposition material was changed to aluminum, oxygen was introduced, and an inorganic thin film layer made of aluminum oxide having a thickness of about 10 nm was formed to obtain an aluminum oxide vapor deposited PET film. The obtained silicon oxide-deposited PET film had an oxygen transmission rate of 11 fmol / m ² / s / Pa, and the aluminum oxide-deposited PET film had an oxygen transmission rate of 9 fmol / m ² / s / Pa.

Production of vapor-deposited nylon film:
Nylon 6 containing 50% by weight of recycled nylon 6 (Mitsubishi Chemical's “Novamid 1020”, relative viscosity = 3.5) was extruded from a T-die at a temperature of 230 ° C., rapidly cooled with a cooling drum, and 144 μm thick A stretched nylon sheet was obtained. The obtained nylon sheet was stretched three times in the longitudinal direction at 60 ° C., and then 60% by weight of an oxazoline group-containing polymer (“Epocross WS-500” manufactured by Nippon Shokubai Co., Ltd.), anchor coat layer resin A (aqueous acrylic resin) 20 An aqueous solution of mixed resin consisting of 20% by weight of resin B (water-based polyurethane resin) for coating by weight is applied by an in-line coating method, stretched three times in the transverse direction at 90 ° C, and heat-treated at 205 ° C. A biaxially stretched nylon film of 16 μm was obtained.

Next, on the anchor coat layer, silicon oxide was vapor-deposited by a high-frequency heating method using a vacuum vapor deposition apparatus to form an inorganic thin film layer made of silicon oxide having a thickness of about 10 nm to obtain a vapor-deposited nylon film. The vapor transmission nylon film had an oxygen permeability of 25 fmol / m ² / s / Pa.

Example 1:
A coating agent was applied on the silicon oxide thin film of the silicon oxide vapor-deposited PET film, and then dried at 100 ° C. for 60 seconds to form a 0.5 μm coating layer. Coating agent: glass transition temperature 60 ° C., molecular weight 8000, acid value 23 mg KOH / g polyester resin 10 parts by weight, glass transition temperature 75 ° C., molecular weight 8000, acid value 20 mg KOH / g polyurethane resin 10 parts by weight, silane coupling It consists of 1 part by weight of γ-glycidoxypropyltrimethoxysilane as an agent, 1 part by weight of stearamide as a fatty acid amide compound, 39 parts by weight of toluene, and 39 parts by weight of methyl ethyl ketone (MEK). “Coronate L” was added 1.2 times the total of hydroxyl value equivalents. The obtained PET film had an oxygen transmission rate of 6 fmol / m ² / s / Pa.

  Gravure printing ink was used as the printing ink on the coating layer of the vapor-deposited PET film, and a printed pattern consisting of five colors of black, indigo, red, yellow and white was formed to evaluate the transferability of the printed pattern. .

  Further, a urethane-based adhesive ("AD-900" manufactured by Toyo Morton Co., Ltd. and "CAT-RT85" mixed at a ratio of 10: 1.5) is applied onto the printed layer of the above-described vapor-deposited PET film and dried. Thus, an adhesive resin layer having a thickness of 4 μm was formed. On this adhesive resin layer, an unstretched polypropylene (PP) film (“Torphan NO ZK-93K” manufactured by Toray Synthetic Film Co., Ltd.) having a thickness of 50 μm is laminated, and PET film / inorganic thin film layer / coating layer / printing layer A transparent laminated film having a layer structure of / adhesive resin layer / PP film was obtained. The obtained laminated film was aged at 40 ° C. for 3 days to obtain a film for evaluation, and the oxygen permeability and adhesion strength were evaluated. Furthermore, the film for evaluation was subjected to hot water treatment at 120 ° C. for 30 minutes in an autoclave, and the oxygen permeability and adhesion strength after the hot water treatment were measured. The evaluation results are shown in Table 6.

Example 2:
In Example 1, the polyester resin used in the coating agent was subjected to the same operation as in Example 1 except that the polyester resin was changed to a polyester resin having a glass transition temperature of 65 ° C., a molecular weight of 15000, and an acid value of 10 mgKOH / g. It was created. The obtained film for evaluation was subjected to the same hot water treatment as in Example 1, and the oxygen transmission rate and adhesion strength before and after the hot water treatment were measured. The evaluation results are shown in Table 6.

Example 3:
In Example 1, the polyester resin used in the coating agent was changed to a polyester resin having a glass transition temperature of 85 ° C., a molecular weight of 30000, and an acid value of 15 mg KOH / g, and the polyurethane resin used in the coating agent was a glass transition temperature of 57. An evaluation film was prepared in the same manner as in Example 1 except that the polyurethane resin having a molecular weight of 3000 and an acid value of 42 mgKOH / g was used. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hot water treatment were measured. The evaluation results are shown in Table 6.

Example 4:
In Example 1, the polyester resin used in the coating agent was changed to a polyester resin having a glass transition temperature of 85 ° C., a molecular weight of 30000, and an acid value of 15 mgKOH / g, and the polyurethane resin used in the coating agent was a glass transition temperature of 65 An evaluation film was prepared in the same manner as in Example 1 except that the urethane resin having a molecular weight of 15000 and an acid value of 10 mgKOH / g was used. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hot water treatment were measured. The evaluation results are shown in Table 6.

Example 5:
In Example 1, except that the thickness of the coating layer was changed to 0.1 μm, the same operation as in Example 1 was performed to prepare an evaluation film. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen transmission rate and adhesion strength before and after the hot water treatment were measured.

Example 6:
In Example 1, except that the thickness of the coating layer was changed to 3 μm, the same operation as in Example 1 was performed to prepare an evaluation film. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen transmission rate and adhesion strength before and after the hot water treatment were measured.

Example 7
On the printing layer of the film comprising PET film / inorganic thin film layer / coating layer / printing layer obtained in Example 1, urethane adhesives (“AD-900” and “CAT-RT85” manufactured by Toyo Morton Co., Ltd.) Were mixed at a ratio of 10: 1.5 and dried to form an adhesive resin layer having a thickness of 4 μm. On this adhesive resin layer, a biaxially stretched nylon film (“Santonyl SNR” manufactured by Mitsubishi Plastics) having a thickness of 15 μm was laminated. Furthermore, on the biaxially stretched nylon film, a urethane adhesive (“AD-900” manufactured by Toyo Morton Co., Ltd. and “CAT-RT85” mixed at a ratio of 10: 1.5) was applied and dried, An adhesive resin layer having a thickness of 4 μm was formed. On this adhesive resin layer, an unstretched polypropylene (PP) film (“Torphan NO ZK-93K” manufactured by Toray Synthetic Film Co., Ltd.) having a thickness of 50 μm is laminated, and PET film / inorganic thin film layer / coating layer / printing layer A transparent laminated film having a layer structure of / adhesive resin layer / nylon film / adhesive resin layer / PP film was obtained. The obtained laminated film was aged at 40 ° C. for 3 days to obtain a film for evaluation, and the oxygen permeability and adhesion strength were evaluated. Furthermore, the film for evaluation was subjected to hot water treatment at 120 ° C. for 30 minutes in an autoclave, and the oxygen permeability and adhesion strength after the hot water treatment were measured. Table 7 shows the evaluation results.

Example 8:
A film for evaluation was prepared in the same manner as in Example 1 except that the silicon oxide-deposited PET film was heat-treated in an oven at 150 ° C. for 30 minutes in Example 1. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen transmission rate and adhesion strength before and after the hot water treatment were measured.

Example 9:
A film for evaluation was prepared in the same manner as in Example 1 except that an aluminum oxide vapor-deposited PET film was used instead of the silicon oxide vapor-deposited PET film. The obtained evaluation film was subjected to the same hydrothermal treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hydrothermal treatment were measured.

Example 10:
A film for evaluation was carried out in the same manner as in Example 1, except that the plastic substrate was changed to a biaxially stretched nylon film ("Santonyl SNR", (ONY) manufactured by Mitsubishi Plastics) with a thickness of 15 μm. It was created. The obtained evaluation film was subjected to the same hydrothermal treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hydrothermal treatment were measured.

Example 11:
About the mixed resin composition which forms the anchor coat layer of silicon oxide vapor deposition PET film, coating resin A (acrylic resin) 40% by weight, coating resin B (polyurethane resin) 40% by weight, oxazoline group-containing polymer (manufactured by Nippon Shokubai Co., Ltd. Epocros WS-500 ") was changed to 20% by weight, and a silicon oxide-deposited PET film was prepared. Using this silicon oxide-deposited PET film, the same operation as in Example 1 was performed to prepare an evaluation film. The obtained evaluation film was subjected to the same hydrothermal treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hydrothermal treatment were measured.

Example 12:
Using the silicon oxide-deposited PET film used in Example 11, the same operation as in Example 1 was performed to prepare a film composed of PET film / inorganic thin film layer / coating layer / printing layer. On the printed layer of the obtained film, a urethane-based adhesive (“AD-900” manufactured by Toyo Morton Co., Ltd. and “CAT-RT85” mixed at a ratio of 10: 1.5) was applied and dried. An adhesive resin layer having a thickness of 4 μm was formed. On this adhesive resin layer, a biaxially stretched nylon film (“Santonyl SNR” manufactured by Mitsubishi Plastics) having a thickness of 15 μm was laminated. Furthermore, on the biaxially stretched nylon film, a urethane adhesive (“AD-900” manufactured by Toyo Morton Co., Ltd. and “CAT-RT85” mixed at a ratio of 10: 1.5) was applied and dried, An adhesive resin layer having a thickness of 4 μm was formed. On this adhesive resin layer, an unstretched polypropylene (PP) film (“Torphan NO ZK-93K” manufactured by Toray Synthetic Film Co., Ltd.) having a thickness of 50 μm is laminated, and PET film / inorganic thin film layer / coating layer / printing layer A transparent laminated film having a layer structure of / adhesive resin layer / nylon film / adhesive resin layer / PP film was obtained. The obtained laminated film was heat-treated in an oven at 150 ° C. for 30 minutes to obtain an evaluation film, and the oxygen permeability and adhesion strength were evaluated. Furthermore, the film for evaluation was subjected to hot water treatment at 120 ° C. for 30 minutes in an autoclave, and the oxygen permeability and adhesion strength after the hot water treatment were measured. The evaluation results are shown in Table 8.

Example 13:
In Example 1, as a coating agent, a hydrolyzed mixed coating consisting of 100 parts by weight of coating resin C (allocoxysilyl group-containing polyurethane resin) and 2 parts by weight of a methoxysilane partial condensate (manufactured by Mitsubishi Chemical Corporation, “MS51”) An evaluation film was prepared in the same manner as in Example 1 except that the agent was used. The obtained evaluation film was subjected to the same hot water treatment as in Example 1 and the oxygen permeability and adhesion strength before and after the hot water treatment were measured.

Comparative Example 1:
In Example 1, an evaluation film was prepared in the same manner as in Example 1 except that 20 parts by weight of scaly silica having an average particle size of 0.5 μm was added to 100 parts by weight of the coating agent. The obtained evaluation film was subjected to the same hot water treatment as in Example 1 and the oxygen permeability and adhesion strength before and after the hot water treatment were measured.

Comparative Example 2:
In Example 11, an evaluation film was prepared in the same manner as in Example 11 except that 50 parts by weight of silica sol having an average particle diameter of 10 nm was added to 100 parts by weight of the coating agent. The obtained evaluation film was subjected to the same hot water treatment as in Example 1 and the oxygen permeability and adhesion strength before and after the hot water treatment were measured.

Comparative Example 3:
The polyester resin used in the coating agent of Example 1 is the same as that of Example 1 except that the polyester resin has a glass transition temperature of 57 ° C., a molecular weight of 3000, and an acid value of 42 mgKOH / g. Created. The obtained evaluation film was subjected to the same hot water treatment as in Example 1 and the oxygen permeability and adhesion strength before and after the hot water treatment were measured.

Comparative Example 4 :
In Example 1, except that the coating layer was not provided, the same operation as in Example 1 was performed to prepare an evaluation film. The obtained evaluation film was subjected to the same hot water treatment as in Example 1, and the oxygen permeability and adhesion strength before and after the hot water treatment were measured. The evaluation results are shown in Table 10.

Claims (12)

It consists of a plastic substrate (A), an inorganic thin film (B) formed on at least one side of the plastic substrate (A), and a coating layer (C) formed on the surface of the inorganic thin film (B). It is a gas barrier laminate, the hardness of the coating layer (C) measured by the nano-indent method in the atmosphere at 23 ° C. is 0.1 to 0.5 GPa, and the thickness is 60 μm on the coating layer (C). When the gas barrier laminate obtained by laminating the unstretched polypropylene film is subjected to hydrothermal treatment at 120 ° C. for 30 minutes, the oxygen permeability of the gas barrier laminate is 50 fmol / m ² / s / Pa or less. Ah is, the resin component forming the coating layer (C) is, (i) a combination of polyester resin and urethane resin, (ii) an acrylic resin and a urethane resin and an oxazoline group-containing resin combination, or, ( iii) Al Kishishiriru group-containing urethane gas barrier laminate according to the resin der characterized Rukoto. It consists of a plastic substrate (A), an inorganic thin film (B) formed on at least one side of the plastic substrate (A), and a coating layer (C) formed on the surface of the inorganic thin film (B). It is a gas barrier laminate, and the hardness of the coating layer (C) measured by the nano-indent method in water at 23 ° C. is 0.03 to 0.5 GPa, and the thickness is 60 μm on the coating layer (C). The oxygen permeability of the gas barrier laminate after performing hydrothermal treatment at 120 ° C. for 30 minutes is 50 fmol / m ² / s / Pa or less for the gas barrier laminate formed by laminating unstretched polypropylene films. The resin component forming the coating layer (C) is (i) a combination of a polyester resin and a urethane resin, (ii) a combination of an acrylic resin, a urethane resin, and an oxazoline group-containing resin, or (iii) ) Al Kishishiriru group-containing urethane gas barrier laminate according to the resin der characterized Rukoto. It consists of a plastic substrate (A), an inorganic thin film (B) formed on at least one side of the plastic substrate (A), and a coating layer (C) formed on the surface of the inorganic thin film (B). It is a gas barrier laminate, and the ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is 0.005 to 0.1, and the coating layer (C) The gas barrier laminate obtained by laminating an unstretched polypropylene film having a thickness of 60 μm on top of the hydrothermal treatment at 120 ° C. for 30 minutes has an oxygen permeability of 50 fmol / m ² / s / Pa Ri der hereinafter resin component forming the coating layer (C) is, (i) a polyester resin and urethane resin combination, (ii) an acrylic resin and a urethane resin and an oxazoline group-containing resin Combination or (i ii) an alkoxysilyl group-containing urethane resin der gas barrier laminate according to claim Rukoto.   The gas barrier laminate according to claim 1 or 2, wherein the ratio of the number of carbons derived from carboxyl groups to the number of carbons constituting the surface of the coating layer (C) is 0.005 to 0.1. The gas barrier laminate after printing on the surface of the coating layer (C) and further subjecting the gas barrier laminate obtained by laminating an unstretched polypropylene film having a thickness of 60 μm to hydrothermal treatment at 120 ° C. for 30 minutes. The gas barrier laminate according to any one of claims 1 to 4 , wherein the oxygen permeability of the gas barrier layer is 50 fmol / m ² / s / Pa or less. The gas barrier laminate according to any one of claims 1 to 5 , wherein the inorganic thin film (B) is a physical vapor deposition film or a chemical vapor deposition film made of silicon oxide, aluminum oxide, diamond-like carbon, or a mixture thereof. The gas barrier laminate according to any one of claims 1 to 6 , further comprising an anchor coat layer between the plastic substrate (A) and the inorganic thin film (B). The anchor coat layer is formed of at least one resin selected from the group consisting of polyester resins, urethane resins, acrylic resins, alkoxysilyl group-containing resins, oxazoline group-containing resins, and copolymer resins thereof. Item 10. A gas barrier laminate according to Item 9. The gas barrier laminate according to any one of claims 1 to 8 , wherein a printing layer is formed on the surface of the coating layer (C), and a heat seal layer is laminated on the surface of the printing layer. The gas barrier laminate according to claim 9 , wherein at least one paper or plastic substrate is laminated between the printed layer and the heat seal layer. The gas barrier laminate according to claim 10, wherein the plastic substrate comprises a polyester resin, a polyamide resin, an ethylene-vinyl acetate copolymer resin, or a mixture thereof. The gas barrier laminate according to any one of claims 1 to 11 , wherein the gas barrier laminate of claim 1 to 11 is subjected to a heat treatment at 60 ° C or higher.