JP2008188975A - Multi-layered structural article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-layered structural article having excellent gas barrier property. <P>SOLUTION: A multi-layered structural article comprises, at least as a part thereof, a two-layered laminate composed of a layer (layer 2) mainly consisting of a gas barrier adhesive resin (C) and a layer (layer 1) consisting of an oxygen absorbing polyamide containing a polyamide (A) obtained by condensation polymerization of a diamine ingredient containing 70 mole% or more of m-xylylene diamine and 50 mole% or more of α,ω-straight-chained aliphatic dicarboxylic acid of 4-20C and a metal compound (B) containing one or more kinds of metal atoms selected from a group consisting of a transitional metal belonging to the group VIII of the periodic system, manganese, copper and zinc. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multilayer structure having oxygen absorbability and good gas barrier properties against oxygen, carbon dioxide, flavor, and the like. More specifically, the present invention relates to a multilayer structure that is suitable for packaging foods, beverages, medicines, and the like and that suppresses a decrease in mechanical strength with time when oxygen is absorbed.

Packaging materials used for packaging foods and beverages not only have functions such as strength, resistance to cracking, and heat resistance to protect the contents from various distributions, storage such as refrigeration and processing such as heat sterilization, Various functions are required, such as excellent transparency so that the contents can be confirmed. Furthermore, in recent years, oxygen barrier properties that prevent the entry of oxygen from the outside in order to suppress food oxidation, carbon dioxide barrier properties, and barrier properties against various fragrance components are also required.

Sheets and films made of polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, and aliphatic polyamides such as nylon 6, are not only transparent and excellent in mechanical properties, but also because they are easy to handle and process. Widely used for materials. However, since the barrier property against gaseous substances such as oxygen is inferior, there is a drawback that the oxidative deterioration of the contents is likely to proceed, and the aromatic component and carbon dioxide are easily permeated, so that the expiration date of the contents is shortened.
In addition, plastic containers (such as bottles) mainly composed of polyester such as polyethylene terephthalate (PET) are widely used for tea, fruit juice drinks, carbonated drinks and the like. The proportion of small plastic bottles in plastic containers is increasing year by year. Since the ratio of the surface area per unit volume increases as the bottle becomes smaller, the shelf life of the contents tends to be shorter when the bottle is made smaller. In recent years, beer plastic bottles, which are easily affected by oxygen and light, and hot sale of plastic bottled tea have been sold, and as the range of use of plastic containers has expanded, gas barrier properties for plastic containers have been further improved. Is required.

  For the purpose of improving the barrier property against gaseous substances such as oxygen, a film in which the thermoplastic resin is combined with a gas barrier resin such as vinylidene chloride, ethylene-vinyl alcohol copolymer or polyvinyl alcohol is used. However, although a film laminated with vinylidene chloride is excellent in gas barrier properties regardless of storage conditions, there is a problem that dioxins are generated when it is burned and the environment is polluted. Although ethylene-vinyl alcohol copolymer and polyvinyl alcohol do not have the above-mentioned environmental pollution problems, multilayer films using these as barrier layers have excellent gas barrier properties when stored in a relatively low humidity environment. However, if the stored contents are high in water activity or stored in a high humidity environment, and after filling the contents, heat sterilization such as so-called boil processing or retort processing is performed. The gas barrier property tends to be greatly reduced, and there is a problem that oxygen permeation into the content increases and a problem occurs in the storage stability of the content.

  By the way, as a material having excellent gas barrier properties, a xylylene group-containing polyamide obtained from a polycondensation reaction of xylylenediamine and an aliphatic dicarboxylic acid, particularly polyamide MXD6 obtained from metaxylylenediamine and adipic acid is known. Polyamide MXD6 is a material that not only exhibits low permeability to gaseous substances such as oxygen and carbon dioxide, but also has excellent heat resistance and molding processability, and is heat sterilized under high humidity, boil and retort treatment, etc. Even when the treatment is performed, it is a material in which the gas barrier property is hardly lowered. However, polyamide MXD6 may be inferior in gas barrier properties at low humidity compared to ethylene-vinyl alcohol copolymer, and the barrier property may be lowered depending on conditions when subjected to boil / retort treatment. It was done.

On the other hand, as a technology for improving the oxygen barrier property of polyamide MXD6, by mixing a transition metal catalyst with polyamide MXD6, oxygen inside the vessel is captured while blocking oxygen from outside the vessel, thereby improving the oxygen barrier property of the vessel. Many techniques for improvement have been disclosed (for example, see Patent Document 1). However, this technique absorbs oxygen by oxidatively decomposing polyamide MXD6, so that the molecular weight decreases with time and the strength of the container is greatly reduced, or the oxidative decomposition product of polyamide MXD6 or the transition metal catalyst is used in the container. Depending on the layer structure, there was a concern of shifting to the contents.
Japanese Patent No. 2991437

  An object of the present invention is to provide a multilayer structure that solves the above-described problems, suppresses a decrease in mechanical strength over time when oxygen is absorbed, and has an excellent gas barrier property that does not cause oxidation decomposition products to migrate to contents. There is.

  As a result of intensive studies, the present inventors have found that a multilayer structure having a specific structure can be obtained to obtain a multilayer structure excellent in gas barrier properties with suppressed deterioration in mechanical strength over time. Arrived.

  That is, the present invention polycondenses a diamine component containing 70 mol% or more of metaxylylenediamine and a dicarboxylic acid component containing 50 mol% or more of an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. Oxygen absorbency comprising the resulting polyamide (A) and a metal compound (B) containing one or more metal atoms selected from the group consisting of transition metals of group VIII of the periodic table, manganese, copper and zinc The present invention relates to a multilayer structure in which at least a part is formed of a laminate composed of at least two layers of a layer (layer 1) made of polyamide and a layer (layer 2) mainly composed of a gas barrier adhesive resin (C).

  According to the present invention, it is possible to obtain a multi-layer structure having excellent gas barrier properties and suppressed reduction in mechanical strength, so that the industrial significance of the present invention is great.

The multilayer structure of the present invention comprises a diamine component containing 70 mol% or more of metaxylylenediamine and a dicarboxylic acid component containing 50 mol% or more of an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. A polyamide (A) obtained by condensation, and a metal compound (B) containing one or more metal atoms selected from the group consisting of group VIII transition metals of the periodic table, manganese, copper and zinc; At least a part is formed of a laminate composed of at least two layers of a layer (layer 1) made of oxygen-absorbing polyamide and a layer (layer 2) mainly composed of a gas barrier adhesive resin (C). It is more preferable that at least a part of the layered body in which at least three layers of (layer 2) / (layer 1) / (layer 2) are laminated in this order is more preferable.

Examples of the multilayer structure of the present invention include films and sheets, molded products thereof, cups and trays, lids, bottles, tubes, pouches, standing pouches, and bag-like containers, but are not limited thereto.

By laminating (Layer 1) and (Layer 2) having excellent gas barrier properties, the amount of oxygen flowing into (Layer 1) is reduced, and the oxygen absorption amount of (Layer 1) is reduced. It is possible to suppress a decrease over time. Further, since (Layer 2) has adhesiveness, it is possible to maintain good mechanical strength even when (Layer 1) absorbs oxygen. Furthermore, (layer 1) and (layer 2) having excellent gas barrier properties are laminated, so that barrier properties such as oxygen, carbon dioxide and flavor are better than when (layer 1) or (layer 2) is used alone. Become.

Furthermore, by laminating the oxygen-absorbing polyamide layer (layer 1) and the adhesive layer (layer 2) having excellent gas barrier properties, the amount of oxygen flowing into (layer 1) decreases, and the oxygen absorption amount of (layer 1) Is reduced, it is possible to prevent the oxidative decomposition product of polyamide (A). In addition, when (Layer 2) is present on the content side of (Layer 1), since (Layer 2) is excellent in barrier properties, the oxidative decomposition product of polyamide (A) or the content of the transition metal catalyst is used. Can be prevented.

The thickness of (Layer 1) in the laminate is preferably from 0.1 to 100 μm, more preferably from 1 to 60 μm, still more preferably from 3 to 30 μm. The thickness of (Layer 2) is preferably 0.1 to 100 μm, more preferably 0.5 to 10 μm.

The polyamide (A) constituting (Layer 1) is composed of a diamine component mainly composed of metaxylylenediamine and a dicarboxylic acid component mainly composed of an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. Is obtained by polycondensation. Polyamide (A) has high barrier performance and good heat resistance and molding processability.

The diamine component in the polyamide (A) contains metaxylylenediamine at 70 mol% or more, preferably 75 mol% or more, more preferably 80 mol% or more. When the amount of metaxylylenediamine in the diamine component is less than 70 mol%, the gas barrier property of the polyamide (A) is lowered, which is not preferable. Examples of diamine components that can be used in addition to metaxylylenediamine in the present invention include tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, Aliphatic diamines such as dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, 2,4,4-trimethylhexamethylenediamine; 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (amino) Methyl) cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminomethyl) de Alicyclic diamines such as phosphorus and bis (aminomethyl) tricyclodecane; diamines having aromatic rings such as bis (4-aminophenyl) ether, paraphenylenediamine, paraxylylenediamine, and bis (aminomethyl) naphthalene However, the present invention is not limited to these examples.

  The dicarboxylic acid component in the polyamide (A) contains an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms in an amount of 50 mol% or more, preferably 70 mol% or more, more preferably 80 mol% or more. When it is in the above range, the polyamide has excellent barrier properties and moldability. Examples of the α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms used in the present invention include succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, adipic acid, sebacic acid, undecanedioic acid, Aliphatic dicarboxylic acids such as dodecanedioic acid can be exemplified, but among these, adipic acid is preferred.

In the present invention, as dicarboxylic acids other than the α, ω-linear aliphatic dicarboxylic acid, aromatic dicarboxylic acids exemplified by terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, etc. It can also be added. Furthermore, a small amount of monoamine or monocarboxylic acid may be added as a molecular weight regulator during the polycondensation of the polyamide.
In the present invention, a dicarboxylic acid component containing 99.5 to 50 mol% of α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms and 0.5 to 50 mol% of aromatic dicarboxylic acid is used. be able to.

The production method of the polyamide (A) is not particularly limited, and is produced by a conventionally known method and polymerization conditions. A small amount of monoamine or monocarboxylic acid may be added as a molecular weight regulator during the polycondensation of the polyamide. For example, it is produced by a method in which a nylon salt composed of metaxylylenediamine and adipic acid is heated in the presence of water in a pressurized state and polymerized in a molten state while removing added water and condensed water. Further, it is also produced by a method in which metaxylylenediamine is directly added to molten adipic acid and polycondensed under normal pressure. In this case, in order to keep the reaction system in a uniform liquid state, metaxylylenediamine is continuously added to adipic acid, and during this time, the reaction system is raised so that the reaction temperature does not fall below the melting point of the generated oligoamide and polyamide. The polycondensation proceeds while warming.

  The polyamide (A) may be subjected to polycondensation by solid-phase polymerization after being produced by a melt polymerization method. The solid phase polymerization method is not particularly limited, and it is produced by a conventionally known method and polymerization conditions.

The number average molecular weight (Mn) of the polyamide (A) is preferably 18000 to 43500, more preferably 20000 to 30000. Within this range, the heat resistance and moldability are good. When the number average molecular weight of the polyamide (A) is 18000 to 43500, the relative viscosity of the polyamide (A) is about 2.3 to 4.2, and when it is 20000 to 30000, about 2.44 to 3.500. 19 The relative viscosity referred to here is a value measured in the same manner for 96% sulfuric acid itself by dissolving 1 g of polyamide in 100 ml of 96% sulfuric acid and measuring it at 25 ° C. using a Canon Fenceke viscometer or the like. Represents the ratio to.

  A phosphorous compound can be added to the polyamide (A) in order to increase the processing stability during melt molding or to prevent the polyamide (A) from being colored. As the phosphorus compound, a phosphorus compound containing an alkali metal or an alkaline earth metal is preferably used. For example, an alkali metal or alkaline earth metal phosphate such as sodium, magnesium, calcium, hypophosphite, phosphorus Acid salts may be mentioned, but those using alkali metal or alkaline earth metal hypophosphites are particularly preferred because they are particularly excellent in the anti-coloring effect of polyamide. The density | concentration of the phosphorus compound in a polyamide (A) is 1-500 ppm as a phosphorus atom, Preferably it is 350 ppm or less.

The metal compound (B) constituting (Layer 1) has a role of acting as a catalyst for imparting an oxygen absorbing function to the polyamide (A). The metal compound (B) contains one or more metal atoms selected from the group consisting of group VIII transition metals of the periodic table, manganese, copper and zinc. These compounds containing metal atoms are preferred because of their high catalytic action for the oxidation reaction of polyamide (A). More preferably, a metal compound containing cobalt, rhodium, iron and / or copper is used. It is preferable that 10-1000 ppm is contained as a metal atom with respect to a polyamide (A), and, as for a metal compound (B), More preferably, it is 50-800 ppm, More preferably, it is 100-600 ppm.

The metal compound (B) used in the present invention is used in the form of a low-valent oxide, inorganic acid salt, organic acid salt or complex salt containing the above metal atom. Examples of inorganic acid salts include halides such as chlorides and bromides, carbonates, sulfates, nitrates, phosphates, silicates, and the like. On the other hand, examples of the organic acid salt include a carboxylate, a sulfonate, and a phosphonate. Also, transition metal complexes with β-diketone or β-keto acid ester can be used. In particular, in the present invention, since oxygen absorbing function is expressed well, it is preferable to use one or more selected from carboxylates, carbonates, acetylacetonate complexes, oxides and halides containing the above metal atoms. It is more preferable to use one or more selected from acid salts, naphthenates, stearates, acetates, carbonates and acetylacetonate complexes.

  The layer (1) can be blended with one or more other resins such as aliphatic polyamide, amorphous semi-aromatic polyamide, polyester, olefin, phenoxy resin and the like within the range not impairing the object of the present invention. In addition, inorganic fillers such as glass fibers and carbon fibers; plate-like inorganic fillers such as glass flakes, talc, kaolin, mica, montmorillonite, and organized clay; impact modifiers such as various elastomers; crystal nucleating agents ; Lubricants such as fatty acid amides, fatty acid metal salts, fatty acid amides; copper compounds, organic or inorganic halogen compounds, hindered phenols, hindered amines, hydrazines, sulfur compounds, phosphorus compounds, etc. Agents; Heat stabilizers; Anti-coloring agents; UV absorbers such as benzotriazoles; Release agents; Plasticizers; Coloring agents; Additives such as flame retardants and addition of alkali compounds for the purpose of preventing gelation of polyamide An agent can be added.

Examples of aliphatic polyamides include poly (6-aminohexanoic acid) (PA-6), also known as poly (caprolactam), poly (hexamethylene adipamide) (PA-6,6), poly (7-aminoheptane) Acid) (PA-7), poly (10-aminodecanoic acid) (PA-10), poly (11-aminoundecanoic acid) (PA-11), poly (hexamethylene sebacamide) (PA-6,10) , Homopolymers such as poly (hexamethylene azelamide) (PA-6,9), poly (tetramethylene adipamide) (PA-4,6), caprolactam / hexamethylene adipamide copolymer (PA-6,6 / Examples include aliphatic polyamides such as 6)). Among these, PA-6 and PA-6, 6 can be preferably used.

As amorphous semi-aromatic polyamides, poly (hexamethylene isophthalamide) (PA-6I), hexamethylene isophthalamide / hexamethylene terephthalamide copolymer (PA-6I / 6T), poly (metaxylylene isophthalate) Lamid) (PA-MXDI), caprolactam / metaxylylene isophthalamide copolymer (PA-6 / MXDI), caprolactam / hexamethylene isophthalamide copolymer (PA-6 / 6I), and the like. Among these, PA-6I / 6T can be preferably used.

There are no particular restrictions on the blending method of these resins and additives, and they may be supplied by dry blending at the time of (Layer 1) creation, such as a single screw extruder or a twin screw extruder prior to (Layer 1) creation. Melt blending may be used, or a master batch may be prepared by melt blending.

An anti-whitening agent can be added to (Layer 1) of the present invention as necessary.
The whitening inhibitor used in the present invention is a fatty acid metal salt having 18 to 50 carbon atoms, preferably 18 to 34 carbon atoms. With 18 or more carbon atoms, whitening prevention can be expected. Further, when the number of carbon atoms is 50 or less, uniform dispersion in the barrier layer is good. Fatty acids may have side chains and double bonds, but linear saturated such as stearic acid (C18), eicosanoic acid (C20), behenic acid (C22), montanic acid (C28), triacontanoic acid (C30) Fatty acids are preferred. The metal that forms a salt with the fatty acid is not particularly limited, but sodium, potassium, lithium, calcium, barium, magnesium, strontium, aluminum, zinc, etc. are exemplified, and sodium, potassium, lithium, calcium, aluminum, and zinc are particularly preferable.

  One type of fatty acid metal salt may be used, or two or more types may be used in combination. In the present invention, the particle diameter of the fatty acid metal salt is not particularly limited. However, the smaller the particle diameter, the easier it is to disperse uniformly, so the particle diameter is preferably 0.2 mm or less.

  The addition amount of the fatty acid metal salt is preferably 0.005 to 1.0 part by weight, more preferably 0.05 to 0.5 part by weight, and particularly preferably 0 with respect to 100 parts by weight of the total amount of (Layer 1). .12 to 0.5 parts by weight. Within this range, the whitening prevention effect of (Layer 1) can be expected, and the haze value can be kept low.

  Further, instead of the fatty acid metal salt, a compound selected from the following diamide compounds and diester compounds may be added as a whitening inhibitor. One or two or more diamide compounds may be added, one or two or more diester compounds may be added, one or two or more diamide compounds and one or two or more types These diester compounds may be used in combination.

  The diamide compound is obtained from a fatty acid having 8 to 30 carbon atoms and a diamine having 2 to 10 carbon atoms. When the fatty acid has 8 or more carbon atoms and the diamine has 2 or more carbon atoms, an effect of preventing whitening can be expected. Further, when the fatty acid has 30 or less carbon atoms and the diamine has 10 or less carbon atoms, uniform dispersion is good. The fatty acid may have a side chain or a double bond, but a linear saturated fatty acid is preferred.

  Examples of the fatty acid component of the diamide compound include stearic acid (C18), eicosanoic acid (C20), behenic acid (C22), montanic acid (C28), and triacontanoic acid (C30). Examples of the diamine component of the diamide compound include ethylenediamine, butylenediamine, hexanediamine, xylylenediamine, and bis (aminomethyl) cyclohexane. A diamide compound obtained by combining these is used in the present invention. A diamide compound obtained from a diamine composed mainly of a fatty acid having 8 to 30 carbon atoms and mainly ethylenediamine, or a diamide compound obtained from a fatty acid mainly composed of montanic acid and a diamine having 2 to 10 carbon atoms is preferred.

  The diester compound is obtained from a fatty acid having 8 to 30 carbon atoms and a diol having 2 to 10 carbon atoms. When the fatty acid has 8 or more carbon atoms and the diol has 2 or more carbon atoms, an effect of preventing whitening can be expected. Further, when the fatty acid has 30 or less carbon atoms and the diol has 10 or less carbon atoms, uniform dispersion is good. The fatty acid may have a side chain or a double bond, but a linear saturated fatty acid is preferred.

  Examples of the fatty acid component of the diester compound include stearic acid (C18), eicosanoic acid (C20), behenic acid (C22), montanic acid (C28), triacontanoic acid (C30) and the like. Examples of the diol component of the diester compound include ethylene glycol, propanediol, butanediol, hexanediol, xylylene glycol, and cyclohexanedimethanol. A diester compound obtained by combining these is used in the present invention. Particularly preferred are diester compounds obtained from fatty acids composed mainly of montanic acid and diols composed mainly of ethylene glycol and / or 1,3-butanediol.

  The amount of the diamide compound and / or diester compound added is preferably 0.005 to 1.0 part by weight, more preferably 0.05 to 0.5 part by weight, based on 100 parts by weight of the total amount of (Layer 1). Particularly preferred is 0.12 to 0.5 parts by weight. Within the above range, whitening prevention effect at the time of moisture absorption can be expected.

  A conventionally known mixing method can be applied to the addition of the whitening inhibitor to (Layer 1). For example, a polyamide (A) pellet, a metal compound (B), and a whitening inhibitor may be charged and mixed in a rotating hollow container. In addition, after producing a resin composition containing a high concentration of anti-whitening agent, diluted with a polyamide (A) pellet containing no anti-whitening agent at a predetermined concentration, a method of melt-kneading this, after melt mixing, Subsequently, a method of molding by injection molding or the like is adopted.

In the present invention, when a resin other than polyamide (A) is blended with (Layer 1), an antistatic agent can be added in an amount of 1 to 1000 ppm with respect to 100 parts by weight of the total amount of (Layer 1). When different resins are dry blended, their dielectric constants and the like are different, so depending on the usage environment, separation and classification may occur due to static electricity, and the blending ratio may vary when molded. Therefore, different resins are properly blended by adding an antistatic agent to the barrier layer as necessary.

  As the antistatic agent used in the present invention, known substances such as nonionic surfactants, anionic (anionic) surfactants, and cationic (cationic) surfactants can be used. Nonionic surfactants include ester type, ether type, alkylphenol type polyethylene glycol type surfactants, sorbitan ester type polyhydric alcohol partial ester type surfactants, polyoxyethylene sorbitan ester type ester ether type surfactants. However, it is not limited to these. In the present invention, polyoxyethylene sorbitan monolaurate which is a kind of polyoxyethylene sorbitan ester type ester ether surfactant is preferably used since it has an excellent antistatic effect.

  One type of antistatic agent may be used, or two or more types may be used in combination. The addition amount of the antistatic agent is preferably 1 to 1000 ppm, more preferably 10 to 500 ppm, and particularly preferably 20 to 100 ppm with respect to the total amount of the barrier layer. Within this range, the blending ratio of polyamide is stable, and a multilayer structure with stable quality can be produced.

The gas barrier adhesive resin (C) which is the main component of (Layer 2) is not particularly limited as long as it is a resin having a barrier property against oxygen or the like, but is mainly composed of a cured epoxy resin and / or a cured polyurethane resin. It is preferable to do. Further, the gas barrier adhesive resin (C) preferably has an oxygen barrier property of an oxygen permeability coefficient of 1.0 ml · mm / m ² · day · MPa (23 ° C., 60% RH) or less. Within this range, the gas barrier adhesive resin (C) is preferable because it has good barriers against not only oxygen but also other gases such as carbon dioxide and various flavors. Further, since the amount of oxygen flowing into (Layer 1) decreases and the amount of oxygen absorbed by (Layer 1) decreases, it is possible to suppress a decrease in mechanical strength of the multilayer structure with time, and polyamide MXD6 Generation of oxidative degradation products of can be prevented.

In the present invention, the cured epoxy resin is obtained by curing an epoxy resin composition comprising an epoxy resin and an epoxy resin curing agent, and the skeleton structure of the following formula (1) is 40 wt% in the cured epoxy resin. % Or more, preferably 45% by weight or more, more preferably 50% by weight or more. When the skeleton structure represented by the following formula (1) is contained at a high level in the cured epoxy resin, a high gas barrier property is exhibited. Due to this high gas barrier property, it is possible to prevent oxygen from flowing into (Layer 1) and to prevent the strength of the multilayer structure from being reduced and the generation and migration of decomposition products. Further, by laminating (Layer 1) and (Layer 2), the multilayer structure of the present invention absorbs a trace amount of oxygen that permeates (Layer 2), and (Layer 1) absorbs extremely high amounts of various gases. Has barrier properties. Below, the epoxy resin and epoxy resin hardening | curing agent which are the main components of an epoxy resin composition are demonstrated.

  The epoxy resin in the present invention may be any of an aliphatic compound, an alicyclic compound, an aromatic compound, or a heterocyclic compound. Is preferable, and an epoxy resin containing the skeleton structure of the above formula (1) in the molecule is more preferable. Specifically, an epoxy resin having a glycidylamino group derived from metaxylylenediamine, an epoxy resin having a glycidylamino group derived from 1,3-bis (aminomethyl) cyclohexane, and a glycidylamino derived from diaminodiphenylmethane Epoxy resin having glycidylamino group and / or glycidyloxy group derived from paraaminophenol, epoxy resin having glycidyloxy group derived from bisphenol A, glycidyloxy group derived from bisphenol F Epoxy resin having glycidyloxy group derived from phenol novolac, epoxy resin having glycidyloxy group derived from resorcinol, etc. can be used, But with epoxy resin having glycidylamino group derived from metaxylylenediamine, epoxy resin having glycidylamino group derived from 1,3-bis (aminomethyl) cyclohexane, glycidyloxy group derived from bisphenol F Epoxy resins and epoxy resins having glycidyloxy groups derived from resorcinol are preferred.

  Furthermore, it is more preferable to use an epoxy resin having a glycidyloxy group derived from bisphenol F or an epoxy resin having a glycidylamino group derived from metaxylylenediamine as a main component. It is particularly preferable to use an epoxy resin having a glycidylamino group as a main component.

  Moreover, in order to improve various performances such as flexibility, impact resistance, and moist heat resistance, the above-mentioned various epoxy resins can be mixed and used at an appropriate ratio.

  The epoxy resin used in the present invention is obtained by reaction of various alcohols, phenols and amines with epihalohydrin. For example, an epoxy resin having a glycidylamino group derived from metaxylylenediamine can be obtained by adding epichlorohydrin to metaxylylenediamine. Since metaxylylenediamine has four amino hydrogens, mono-, di-, tri- and tetraglycidyl compounds are formed. The number of glycidyl groups can be changed by changing the reaction ratio between metaxylylenediamine and epichlorohydrin. For example, an epoxy resin having mainly four glycidyl groups can be obtained by addition reaction of about 4 times mole of epichlorohydrin to metaxylylenediamine.

The epoxy resin is an excess of epihalohydrin with respect to various alcohols, phenols and amines in the presence of an alkali such as sodium hydroxide, 20 to 140 ° C., preferably 50 to 120 ° C. in the case of alcohols and phenols, amine In the case of a kind, it is synthesized by reacting at a temperature of 20 to 70 ° C. and separating the produced alkali halide.
The number average molecular weight of the produced epoxy resin varies depending on the molar ratio of epihalohydrin to various alcohols, phenols and amines, but is about 80 to 4000, preferably about 200 to 1000, preferably about 200 to 500. It is more preferable.

The epoxy resin curing agent in the present invention may be any of an aliphatic compound, an alicyclic compound, an aromatic compound, or a heterocyclic compound, such as polyamines, phenols, acid anhydrides, or carboxylic acids. Any commonly used epoxy resin curing agent can be used. These epoxy resin curing agents can be selected according to the use application of the laminate and the required performance in the application.
Specifically, polyamines include aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; aliphatic amines having an aromatic ring such as metaxylylenediamine and paraxylylenediamine; 1,3- Examples include alicyclic amines such as bis (aminomethyl) cyclohexane, isophoronediamine, norbornanediamine; and aromatic amines such as diaminodiphenylmethane and metaphenylenediamine. Also, epoxy resins using these as raw materials, modified reaction products of polyamines and monoglycidyl compounds, modified reaction products of polyamines and epichlorohydrin, modified reaction products of polyamines and alkylene oxides having 2 to 4 carbon atoms, polyamines Amide oligomers, polyamines, polyfunctional compounds having at least one acyl group, and monovalent carboxylic acids and / or derivatives thereof, obtained by reaction of a group with a polyfunctional compound having at least one acyl group The amide oligomer obtained by this reaction can also be used as an epoxy resin curing agent.

Examples of phenols include polyphenols such as catechol, resorcinol and hydroquinone, and resole type phenol resins.
Acid anhydrides or carboxylic acids include aliphatic acid anhydrides such as dodecenyl succinic anhydride and polyadipic anhydride, and alicyclic acid anhydrides such as (methyl) tetrahydrophthalic anhydride and (methyl) hexahydrophthalic anhydride. Aromatic acid anhydrides such as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and carboxylic acids thereof can be used.

In consideration of the expression of high gas barrier properties, an epoxy resin curing agent containing an aromatic moiety in the molecule is preferred, and an epoxy resin curing agent containing the skeleton structure of the above formula (1) in the molecule is more preferred.
Specifically, metaxylylenediamine or paraxylylenediamine, reaction products with epoxy resins or monoglycidyl compounds using these as raw materials, reaction products with alkylene oxides having 2 to 4 carbon atoms, epichlorohydrin Reaction products with these polyamines, reaction products with polyfunctional compounds having at least one acyl group that can form oligomers by reaction with these polyamines, and with these polyamines It is more preferable to use a reaction product of a polyfunctional compound having at least one acyl group and a monovalent carboxylic acid and / or a derivative thereof, which can form an amide group site by the reaction of preferable.

When considering high gas barrier properties and good adhesiveness, the following reaction products (D) and (E) or reactions (D), (E), and (F) are used as epoxy resin curing agents. It is particularly preferred to use the product.
(D) a polyfunctional compound having at least one acyl group capable of forming an amide group site by reaction with metaxylylenediamine or paraxylylenediamine (E) polyamine to form an oligomer (F) having 1 to 1 carbon atoms 8 monovalent carboxylic acids and / or derivatives thereof

  The polyfunctional compound having at least one acyl group that can form an amide group site by reaction with the (E) polyamine to form an oligomer includes acrylic acid, methacrylic acid, maleic acid, fumaric acid, succinic acid, Carboxylic acids such as malic acid, tartaric acid, adipic acid, isophthalic acid, terephthalic acid, pyromellitic acid, trimellitic acid and their derivatives such as esters, amides, acid anhydrides, acid chlorides, etc., especially acrylic acid Methacrylic acid and derivatives thereof are preferred.

  In addition, monovalent carboxylic acids having 1 to 8 carbon atoms such as formic acid, acetic acid, propionic acid, butyric acid, lactic acid, glycolic acid, benzoic acid, and derivatives thereof such as esters, amides, acid anhydrides, acid chlorides, etc. The polyfunctional compound may be used in combination with the starting polyamine. The amide group site introduced by the reaction has a high cohesive force, and the presence of the amide group site in a high proportion in the epoxy resin curing agent provides higher oxygen barrier properties and better adhesive strength.

  The reaction molar ratio of (D) and (E) or (D), (E), and (F) is the reactive functionality contained in (E) with respect to the number of amino groups contained in (D). The ratio of the number of groups or the ratio of the total number of reactive functional groups contained in (E) and (F) to the number of amino groups contained in (D) is in the range of 0.3 to 0.97. Is preferred. When the ratio is less than 0.3, a sufficient amount of amide groups are not generated in the epoxy resin curing agent, and a high level of gas barrier properties and adhesiveness are not exhibited. Moreover, the ratio of the volatile molecule which remains in the epoxy resin curing agent is increased, which causes odor generation from the obtained cured product. Moreover, since the ratio of the hydroxyl group produced | generated by reaction of an epoxy group and an amino group in the hardening reaction material becomes high, it becomes a factor by which oxygen barrier property in a high humidity environment falls remarkably. On the other hand, in the range higher than 0.97, the amount of amino groups reacting with the epoxy resin is reduced, and excellent impact resistance and heat resistance are not exhibited, and the solubility in various organic solvents or water is lowered. When particularly considering the high gas barrier property, high adhesion, suppression of odor generation, and high oxygen barrier property in a high humidity environment of the obtained cured product, the molar ratio of the polyfunctional compound to the polyamine component is 0.6. A range of ˜0.97 is more preferable. In consideration of the expression of a higher level of adhesiveness, it is preferable that the epoxy resin curing agent in the present invention contains at least 6% by weight of an amide group based on the total weight of the curing agent.

In consideration of the expression of high shear strength, for example, at least 1 that can form an amide group site by forming an amide group site by reacting an epoxy resin curing agent such as metaxylylenediamine or paraxylylenediamine with the polyamine. The reaction ratio of the reaction product with the polyfunctional compound having one acyl group is 0.6 to 0.97, preferably 0.8 to 0.97, particularly preferably molar ratio of the polyfunctional compound to the polyamine component. Is preferably in the range of 0.85 to 0.97, and it is preferable to use an epoxy resin curing agent in which the average molecular weight of the oligomer as the reaction product is increased.
A more preferred epoxy resin curing agent is a reaction product of metaxylylenediamine and acrylic acid, methacrylic acid and / or derivatives thereof. Here, the reaction molar ratio of acrylic acid, methacrylic acid and / or derivatives thereof to metaxylylenediamine is preferably in the range of 0.8 to 0.97.

About the blending ratio of the epoxy resin and the epoxy resin curing agent, which are the main components of the epoxy resin composition, generally in a standard blending range when preparing an epoxy resin cured product by reaction of the epoxy resin and the epoxy resin curing agent. It may be. Specifically, the ratio of the number of active hydrogens in the epoxy resin curing agent to the number of epoxy groups in the epoxy resin is in the range of 0.5 to 5.0. If the range is less than 0.5, the remaining unreacted epoxy group causes the gas barrier property of the resulting cured product to decrease, and if it is greater than 5.0, the remaining unreacted amino group results in the resulting cured product. It becomes a cause of lowering the heat and heat resistance. In the case where gas barrier properties and wet heat resistance of the obtained cured product are particularly taken into consideration, the range of 0.8 to 3.0 is more preferable, and the range of 0.8 to 2.0 is particularly preferable.
In addition, when considering the expression of a high oxygen barrier property in a high humidity environment of the resulting cured product, the ratio of the number of active hydrogens in the epoxy resin curing agent to the number of epoxy groups in the epoxy resin is 0.8. A range of ˜1.6 is preferred.

  The epoxy resin composition is characterized by having a high gas barrier property in a wide range from a low humidity condition to a high humidity condition in addition to suitable adhesive performance. Therefore, by laminating (Layer 1) and (Layer 2), the gas barrier property can be remarkably improved even in a high humidity environment such as when the multilayer structure is subjected to low humidity or boil-retort treatment. , (Layer 1) and a high-barrier property that cannot be achieved with a multilayer structure in which a normal adhesive having no gas barrier property is laminated.

  Furthermore, since the cured epoxy resin in the present invention is excellent in toughness and heat-and-moisture resistance, a laminate excellent in impact resistance, boiling resistance, retort resistance and the like can be obtained.

In the present invention, the polyurethane resin cured product is a two-component curable polyurethane resin composition (hereinafter referred to as “component (G)”) composed mainly of an active hydrogen-containing compound (G) and an organic polyisocyanate compound (H). "Polyurethane resin composition") is obtained by curing.
Below, the active hydrogen containing compound and organic polyisocyanate compound which form a polyurethane resin composition are demonstrated.

In the polyurethane resin composition, the active hydrogen-containing compound is at least one compound selected from an alkylene oxide adduct of polyamine, an amide group-containing polyol, a polyol adduct of a polyisocyanate compound, and a polyol. These may be any of an aliphatic compound, an alicyclic compound, an araliphatic compound, and an aromatic compound, and can be appropriately selected according to the intended use and required performance in the intended use. In consideration of the expression of high gas barrier properties and good adhesiveness, an active hydrogen-containing compound containing an aromatic moiety or an alicyclic moiety in the molecule is preferable, and the active hydrogen containing the skeleton structure (1) in the molecule Containing compounds are more preferred. Further, the active hydrogen-containing compound has an amino group and / or a hydroxyl group as a terminal functional group, and the total number of active hydrogens in the compound is 2 or more. However, when high gas barrier properties and good adhesiveness are considered. The total number of active hydrogens is preferably 3 or more, more preferably 4 or more.

Examples of the polyamine include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, ethanolamine, propanolamine, and other aliphatic polyamines, 1,3- or 1,4-bis (aminomethyl) cyclohexane, Alicyclic polyamines such as 4,4′-, 2,4′- or 2,2′-dicyclohexylmethanediamine, isophoronediamine, norbornanediamine, m- or p-xylylenediamine, 1,3- or 1,4 -Aromatic polyamines such as tetramethylxylylenediamine, aromatic polyamines such as 2,4- or 2,6-tolylenediamine, 4,4'-, 2,4'- or 2,2'-diaminodiphenylmethane Can be illustrated.

Examples of the amide group-containing polyol include hydroxyalkylamides.

Examples of the polyisocyanate compound include m- or p-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate, 4,4′-, 2,4′- or 2,2′-diphenylmethane diisocyanate, 4, Aromatic polyisocyanates such as 4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 1,5- or 2,6-naphthalene diisocyanate, m- or p-xylylene diisocyanate, 1,3- or 1,4- Aroaliphatic polyisocyanates such as tetramethylxylylene diisocyanate, 1,3- or 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane, 4,4'- , 2, 4 ' Or alicyclic polyisocyanates such as 2,2′-dicyclohexylmethane diisocyanate and norbornane diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, the above aromatic polyisocyanates, araliphatic polyisocyanates, alicyclic polyisocyanates, aliphatic Examples include polyisocyanate burettes, allophanates, uretdiones, and isocyanurates.

Examples of the polyol include ethylene glycol, 1,2- or 1,3-propanediol, 1,3- or 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, , 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, neopentyl Aliphatic polyols such as glycol, glycerin, trimethylolpropane, pentaerythritol, alicyclic polyols such as 1,3- or 1,4-cyclohexanedimethanol, and araliphatic polyols such as m- or p-xylylene glycol. It can be illustrated.

The alkylene oxide adduct of the polyamine exhibits high gas barrier properties and adhesiveness regardless of the number of carbon atoms of the alkylene oxide. However, when higher gas barrier properties and good adhesiveness are considered, the alkylene oxide adduct The number of carbon atoms is preferably 2 to 4. The reaction molar ratio between the polyamine and the alkylene oxide expresses a gas barrier property in any case, but when considering the expression of higher gas barrier property and good adhesiveness, the molar ratio ([alkylene oxide] / [Polyamine]) is preferably in the range of 2-16.

The polyol to be added to the polyisocyanate compound may be any of the above polyols, and any of the reaction equivalent ratios exhibits high gas barrier properties and adhesiveness, but higher gas barrier properties and good adhesiveness. In consideration of the expression of, the equivalent ratio ([polyol] / [polyisocyanate compound]) is preferably in the range of 2-20. The reaction method is not particularly limited as the order of addition of the constituent components, and the conventional methods such as mixing all of the components sequentially or simultaneously, or re-adding a polyisocyanate compound as needed during the reaction as necessary. Various methods used in the field can be adopted. In the reaction, an organic solvent can be used as necessary. Examples of the organic solvent include toluene, xylene, ethyl acetate, butyl acetate, cellosolve acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dimethylformamide, dimethylacetamide and the like. These organic solvents can be used alone or in combination of two or more. Further, during the reaction, a known organometallic compound (lead or tin compound), tertiary amine or the like can be used as a reaction accelerator if necessary.

Furthermore, in order to improve various performances such as flexibility, impact resistance, and moist heat resistance, the active hydrogen-containing compound can be used alone or as a mixture mixed at an appropriate ratio.

The active hydrogen-containing compound includes an aromatic oxide polyamine alkylene oxide adduct, an araliphatic polyisocyanate compound polyol adduct, and an araliphatic polyol in consideration of higher gas barrier properties and good adhesiveness. And more preferred are alkylene oxide adducts of araliphatic polyamines.

In the polyurethane resin composition, the organic polyisocyanate compound comprises (a) a reaction product of a polyfunctional isocyanate compound and (b) a polyfunctional alcohol, or (a) a polyfunctional isocyanate compound, (b) a polyfunctional alcohol and (c ) A reaction product of a polyfunctional amine and / or a polyfunctional carboxylic acid, which has two or more NCO groups at its end. These may be any of an aliphatic compound, an alicyclic compound, an araliphatic compound, and an aromatic compound, and can be appropriately selected depending on the intended use and required performance in the intended use. In view of gas barrier properties and good adhesion, organic polyisocyanate compounds containing aromatic or alicyclic moieties in the molecule are preferred, and organic polyisocyanate compounds containing the skeleton structure (1) above in the molecule are preferred. An isocyanate compound is more preferable. The reaction equivalent ratio of the components (a) and (b) or the components (a), (b) and (c) can express high gas barrier properties and adhesion properties, but higher gas barrier properties. Considering the expression of good adhesiveness, the equivalent ratio ([component (a)] / [component (b)] or [component (a)] / [component (b) + component (c)]) is 2 It is preferably ~ 30.

The reaction method for producing the organic polyisocyanate compound is not particularly limited in the order of addition of the constituent components, and the total amount of each component is mixed sequentially or simultaneously, or if necessary, a polyfunctional isocyanate compound is appropriately added during the reaction. Various methods conventionally used in this field, such as re-addition, can be employed. Moreover, an organic solvent can be used at the time of reaction as needed. Examples of the organic solvent include toluene, xylene, ethyl acetate, butyl acetate, cellosolve acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dimethylformamide, dimethylacetamide and the like. These organic solvents can be used alone or in combination of two or more. Further, during the reaction, a known organometallic compound (lead or tin compound), tertiary amine or the like can be used as a reaction accelerator if necessary. If excess unreacted component (a) is present in the reaction products of (a) and (b) or in the reaction products of (a), (b) and (c), thin film distillation, extraction It can be removed from the reaction product by an existing method.

As the polyfunctional isocyanate compound as component (a), m- or p-phenylene diisocyanate, 2,4- or 2,6-tolylene diisocyanate, 4,4'-, 2,4'- or 2,2 ' -Aromatic polyfunctional isocyanate compounds such as diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 1,5- or 2,6-naphthalene diisocyanate, m- or p-xylylene diisocyanate, 1 , 3- or 1,4-tetramethylxylylene diisocyanate aromatic aliphatic polyfunctional isocyanate compounds, 1,3- or 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 1,3- or 1,4-bis (isocyanate) Natemethyl) cyclo Cyclohexane, 4,4′-, 2,4′- or 2,2′-dicyclohexylmethane diisocyanate, alicyclic polyfunctional isocyanate compounds such as norbornane diisocyanate, aliphatic polyfunctional isocyanate compounds such as hexamethylene diisocyanate, Examples include aromatic polyfunctional isocyanate compounds, araliphatic polyfunctional isocyanate compounds, alicyclic polyfunctional isocyanate compounds, and aliphatic polyfunctional isocyanate compounds burettes, allophanates, uretdiones, isocyanurates, and the like.

The component (b) is at least one polyfunctional alcohol selected from polyfunctional alcohols having 2 to 10 carbon atoms, and can be appropriately selected according to the intended use and required performance in the intended use. Examples of the polyfunctional alcohol include ethylene glycol, 1,2- or 1,3-propanediol, 1,3- or 1,4-butanediol, 1,5-pentanediol, and 3-methyl-1,5-pentanediol. 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, Aliphatic polyols such as neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol, alicyclic polyols such as 1,3- or 1,4-cyclohexanedimethanol, and araliphatics such as m- or p-xylylene glycol A polyol can be illustrated.

Component (c) is an aromatic polyfunctional amine, an araliphatic polyfunctional amine, an alicyclic polyfunctional amine, an aliphatic polyfunctional amine, an aliphatic alkanolamine, an aromatic polyfunctional carboxylic acid, an alicyclic polyfunctional carboxylic acid. It is at least one compound selected from an acid and an aliphatic polyfunctional carboxylic acid, and can be appropriately selected according to the intended use and required performance in the intended use.

Examples of aromatic polyfunctional amines include 2,4- or 2,6-tolylenediamine, 4,4'-, 2,4'- or 2,2'-diaminodiphenylmethane, and examples of aromatic aliphatic polyfunctional amines include m. Examples of alicyclic polyfunctional amines such as-or p-xylylenediamine, 1,3- or 1,4-tetramethylxylylenediamine include 1,3- or 1,4-bis (aminomethyl) cyclohexane, 4 , 4'-, 2,4'- or 2,2'-dicyclohexylmethanediamine, isophoronediamine, norbornanediamine, etc., and aliphatic polyfunctional amines include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylene Examples of aliphatic alkanolamines such as diamines include ethanolamine and propanolamine. It can be. As aromatic polyfunctional carboxylic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, paraphenylene dicarboxylic acid, trimellitic acid, pyromellitic acid, etc., as alicyclic polyfunctional carboxylic acid, 1,3- Examples of the aliphatic polyfunctional carboxylic acid such as cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid include malonic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid and dodecanedioic acid.

When using as an organic polyisocyanate compound, in consideration of the expression of higher gas barrier properties and good adhesiveness, the polyfunctional isocyanate compound as component (a) is derived from xylylene diisocyanate and xylylene diisocyanate. The compound is preferably at least one compound selected from a burette, allophanate, uretdione, and isocyanurate, and more preferably xylylene diisocyanate.

The polyurethane resin composition contains 20% by weight or more of the skeleton structure represented by the above formula (1) in the cured polyurethane resin formed by the reaction of the components (G) and (H). Preferably, it is 25% by weight or more, more preferably 30% by weight or more. By containing 20% by weight or more of the skeleton structure represented by the formula (1) in the polyurethane resin cured product, it becomes possible to express high gas barrier properties and good adhesiveness.

The polyurethane resin composition can be used as an adhesive for gas barrier laminates. In this case, with respect to the blending ratio of the components (G) and (H) which are the main components of the laminating adhesive, in general, a component mainly composed of an active hydrogen-containing compound and a component mainly composed of an organic polyisocyanate compound. It may be a standard blending range in the case of producing a two-component curable polyurethane resin cured product by a reaction with the above. Specifically, the ratio of the number of isocyanate groups in the organic polyisocyanate compound contained in component (H) to the total number of hydroxyl groups and amino groups in the active hydrogen-containing compound contained in component (G) is 0.8-2. 0, preferably in the range of 0.9 to 1.7.

When considering the expression of high tack, the organic polyisocyanate compound (H) is a reaction product of (a) a polyfunctional isocyanate compound and (b) a polyfunctional alcohol, or (a) a polyfunctional isocyanate compound, It is a reaction product of (b) polyfunctional alcohol and (c) polyfunctional amine and / or polyfunctional carboxylic acid, and it is preferable that the average molecular weight of the oligomer in the product is increased.

  The epoxy resin composition and / or the polyurethane resin composition (hereinafter collectively referred to as “adhesive composition”), if necessary, within a range not impairing the effects of the present invention, A thermosetting resin composition such as a polyurea resin composition may be mixed.

  To the adhesive composition, a wetting agent such as silicon or an acrylic compound may be added as needed to help wet the surface of various materials during application. Suitable wetting agents include BYK331, BYK333, BYK340, BYK347, BYK348, BYK354, BYK380, BYK381, etc., available from Big Chemie. When adding these, the range of 0.01 weight%-2.0 weight% is preferable on the basis of the total weight of adhesive composition.

  To the adhesive composition, a tackifier such as a xylene resin, a terpene resin, a phenol resin, or a rosin resin may be added as necessary in order to improve the adhesiveness to various materials immediately after application. When adding these, the range of 0.01 weight%-5.0 weight% is preferable on the basis of the total weight of an adhesive composition.

Moreover, in order to improve various performances such as gas barrier properties, impact resistance, and heat resistance of the adhesive layer formed by the adhesive composition, silica, alumina, mica, talc, aluminum flakes in the adhesive, Inorganic fillers such as glass flakes may be added.
In consideration of the transparency of the film, it is preferable that such an inorganic filler has a flat plate shape. When adding these, the range of 0.01 weight%-10.0 weight% is preferable on the basis of the total weight of an adhesive composition.

  Furthermore, in order to improve the adhesiveness of the adhesive layer formed by the adhesive composition, a coupling agent such as a silane coupling agent or a titanium coupling agent may be added to the adhesive. When adding these, the range of 0.01 weight%-5.0 weight% is preferable on the basis of the total weight of an adhesive composition.

  Hereinafter, the case where a film or a sheet is produced as a laminate will be described. In the case of laminating various film materials using the adhesive in the present invention, a known laminating method such as dry lamination, non-solvent laminating, extrusion laminating, etc. can be used. Is preferred.

When the adhesive composition is applied to various materials as an adhesive and laminated, it is carried out at a concentration and temperature of the adhesive composition sufficient to obtain a resin cured product to be an adhesive layer. Can vary depending on the choice of starting materials and lamination method. That is, the concentration of the adhesive composition is about 5% by weight using a certain kind of appropriate organic solvent and / or water from the case where no solvent is used, depending on the type and molar ratio of the selected material, the laminating method, and the like. Various states can be taken up to the case where the coating liquid is prepared by diluting to the composition concentration. As the organic solvent to be used, any solvent having solubility with an adhesive can be used. For example, water-insoluble solvents such as toluene, xylene, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, 1-methoxy-2 -Glycol ethers such as propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, acetaldehyde, Examples include aldehydes such as propionaldehyde, aprotic polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, and N-methylpyrrolidone.

  The adhesive (coating solution) diluted with a solvent can be diluted at a concentration such that the Zahn cup (No. 3) viscosity is in the range of 5 to 30 seconds (25 ° C.). If the Zahn cup (No. 3) viscosity is less than 5 seconds, the adhesive is not sufficiently applied to the object to be coated, which causes contamination of the roll. On the other hand, when the Zahn cup (No. 3) viscosity exceeds 30 seconds, the adhesive does not sufficiently transfer to the roll, and it becomes difficult to form a uniform adhesive layer. For example, in dry lamination, the Zahn cup (No. 3) viscosity is preferably 10 to 20 seconds (25 ° C.) during use.

In order to suppress foaming of the coating liquid when preparing the coating liquid in the present invention, an antifoaming agent such as silicon or an acrylic compound may be added to the coating liquid. Examples of suitable antifoaming agents include BYK019, BYK052, BYK063, BYK065, BYK066N, BYK067N, BYK070, BYK080, and Disparon 1930N and 1934, which are available from Enomoto Kasei Co., Ltd., available from Big Chemie. In particular, BYK065 is preferable. Moreover, when adding these antifoamers, the range of 0.001 weight%-3.0 weight% is preferable on the basis of the total weight of the adhesive composition in a coating liquid, 0.005 weight%-2 More preferred is 0.0% by weight.

When a solvent is used, the solvent drying temperature after application of the adhesive may vary from 20 ° C. to 140 ° C., but it is close to the boiling point of the solvent and affects the object to be coated. No temperature is desirable. If the drying temperature is less than 20 ° C., the solvent remains in the gas barrier laminate film, causing adhesion failure and odor. On the other hand, when the drying temperature exceeds 140 ° C., it becomes difficult to obtain a laminated film having a good appearance due to softening of the polymer film. For example, when apply | coating an adhesive agent to a stretched polypropylene film, 40 to 120 degreeC is desirable.

  Any of commonly used coating formats such as roll coating, spray coating, air knife coating, dipping, and brush coating can be used as the coating format for applying the adhesive. Roll coating or spray coating is preferred. For example, the same roll coat or spray technique and equipment as when a polyurethane adhesive component is applied to a polymer film and laminated can be applied.

Next, specific operations in each laminating method will be described. In the case of the dry laminating method, after the coating liquid is applied to a film material including a base material by a roll such as a gravure roll, the solvent is dried and a new film material is immediately bonded to the surface by a nip roll to form a gas barrier laminate. A film can be obtained. The solvent for preparing the adhesive is preferably a solvent having good solubility and a relatively low boiling point and containing an alcohol having 3 or less carbon atoms. The group consisting of methanol, ethanol, isopropanol, and n-propanol The solvent which has as a main component 1 or more types chosen from is illustrated. In addition, it is a mixed solution in which a solvent having an ester group, ketone group, or aldehyde group functional group that has the effect of delaying the reaction between the epoxy resin and the polyamine and suppressing the increase in the viscosity of the adhesive to prolong the working time. Preferably there is. As a mixed liquid in which a solvent having any functional group of an ester group, a ketone group, or an aldehyde group is mixed, it is selected from the group consisting of methyl acetate, ethyl acetate, acetone, methyl ethyl ketone, acetaldehyde, and propionaldehyde having a relatively low boiling point. The liquid mixture which mixed 1 or more types is illustrated. In order to obtain a film having a small amount of solvent remaining in the resulting laminated film, the content of the solvent having any functional group of ester group, ketone group, and aldehyde group is preferably 20% by weight or less in the total solvent. Here, if there is a large amount of solvent remaining in the laminated film, it may cause bad odor. Therefore, the amount of the remaining solvent is practically 7 mg / m ² or less, and if it is more than 7 mg / m ² , a strange odor is felt from the film. Cause. Preferably 5 mg / ^{m 2} or less in the case of strictly control the odor of the film, 3 mg / ^{m 2} or less is particularly preferred.

  In the dry laminating method, the adhesive can also be applied to the sealant layer, applied to a polyolefin film such as a polyethylene film, a polypropylene film, or an ethylene-vinyl acetate copolymer, dried, and then stretched polypropylene or a polyamide film. A laminated film can be produced by laminating a substrate such as a polyethylene terephthalate film.

In the case of bonding by nip roll, the nip roll can be heated and bonded to 20 ° C. to 120 ° C., but 40 to 100 ° C. is desirable.

In this case, it is desirable to complete the curing reaction by performing aging at 20 ° C. to 60 ° C. for a certain time as necessary after lamination. By aging, a cured epoxy resin is formed with a sufficient reaction rate, and high gas barrier properties and adhesive strength are exhibited.

  In the case of the non-solvent laminating method, a roll such as a gravure roll in which the adhesive in the present invention, which has been heated to about 40 ° C. to 100 ° C. in advance on a film material containing a substrate, is heated to 40 ° C. to 120 ° C. After the coating, a gas barrier laminate film can be obtained by pasting a new film material on the surface immediately after coating. In this case as well, as in the case of the dry laminating method, it is desirable to perform aging for a predetermined time after the lamination as necessary.

In the case of the extrusion laminating method, a dilute solution of the adhesive composition, which is the main component of the adhesive in the present invention, as an adhesion auxiliary agent (anchor coating agent) with an organic solvent and / or water is applied to the film material including the substrate. A gas barrier laminate film can be obtained by laminating a polymer material melted by an extruder after coating with a roll such as a roll and drying and curing reaction of a solvent at 20 ° C. to 140 ° C. The polymer material to be melted is preferably a polyolefin resin such as a low density polyethylene resin, a linear low density polyethylene resin, or an ethylene-vinyl acetate copolymer resin.
These laminating methods and other laminating methods that can be generally used can be combined as necessary, and the layer structure of the gas barrier laminate film can be changed depending on the application and form.

  The thickness of the adhesive layer (layer 2) after applying, drying, bonding and heat-treating the adhesive in the present invention to various materials is 0.1 to 100 μm, preferably 0.5 to 10 μm. . If it is this range, an adhesive bond layer will exhibit sufficient gas barrier property and adhesiveness by uniform thickness.

The laminated film has excellent laminate strength. The laminate strength at a peeling speed of 300 mm / min after the heat treatment varies depending on the material of the base material and the sealant layer. For example, when the base material is stretched polypropylene, 80 g / 15 mm or more is preferable, and 100 g / 15 mm or more is more preferable. It is preferably 120 g / 15 mm or more. On the other hand, when the base material is stretched nylon or polyethylene terephthalate, if the sealant layer is low density polyethylene, it is preferably 600 g / 15 mm or more, more preferably 700 g / 15 mm or more, and particularly preferably 800 g / 15 mm or more. If is unstretched polypropylene, it is preferably 300 g / 15 mm or more, more preferably 400 g / 15 mm or more, and particularly preferably 500 g / 15 mm or more.

  The gas barrier laminate film produced using an adhesive comprising the adhesive composition preferably has a laminate strength of 30 g / 15 mm or more immediately after lamination (before aging) at a peeling rate of 300 mm / min, 40 g / 15 mm or more is more preferable, and 50 g / 15 mm or more is particularly preferable. When the laminate strength is not less than the above, it is possible to prevent tunneling of the laminated film or winding deviation when winding the film.

  The multilayer structure of the present invention may include layers other than (Layer 1) and (Layer 2). For example, an unstretched or stretched film made of a thermoplastic resin such as polyester, polyamide, or polypropylene may be laminated by extrusion lamination, dry lamination, or the like for the purpose of improving mechanical properties or improving commercial properties.

The thermoplastic resin that can be used is not particularly limited as long as it can impart an effect of improving mechanical properties. For example, polyethylenes such as low density polyethylene, medium density polyethylene, and high density polyethylene, propylene homopolymer, propylene- Polypropylenes such as ethylene block copolymer and propylene-ethylene random copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer , Propylene-α-olefin copolymers, various polyolefins such as polybutene, polypentene, and ionomer resin, polyester resins such as polystyrene and polyethylene terephthalate, polyamide resins such as nylon 6 and nylon 66, and the like. It is. The layer having the role of maintaining the mechanical properties may be a single layer made of the above-described resin or may have a multilayer structure of two or more layers. Further, paper may be laminated as a layer having a role of maintaining mechanical properties. In the case of a multilayer structure, an adhesive resin layer made of a modified polyolefin resin or the like may be laminated between each layer as necessary.

  Impact resistance modifiers such as various elastomers can be added to the layer that has the role of maintaining the mechanical properties of the multilayer structure to further improve the mechanical properties. , Lubricants such as fatty acid metal salts, fatty acid amide compounds, copper compounds, organic or inorganic halogen compounds, hindered phenols, hindered amines, hydrazines, sulfur compounds, sodium hypophosphite, potassium hypophosphite , Antioxidants such as phosphorus compounds such as calcium hypophosphite and magnesium hypophosphite, heat stabilizers, anti-coloring agents, UV absorbers such as benzotriazoles, mold release agents, plasticizers, coloring agents, flame retardants Additives such as, inorganic pigments such as titanium oxide, and organic pigments such as dyes may be included.

Further, as layers other than (Layer 1) and (Layer 2), metal foil such as aluminum and copper, polyvinylidene chloride (PVDC) resin, polyvinyl alcohol resin, ethylene-vinyl acetate copolymer saponified resin, acrylic Films coated with various polymers such as resin, films deposited with various inorganic compounds or metals such as silica, alumina, and aluminum, films dispersed with inorganic fillers, films with oxygen scavenging function, etc. are also used it can. Moreover, an inorganic filler can be disperse | distributed also about the various polymers to coat. Examples of inorganic fillers include silica, alumina, mica, talc, aluminum flakes, and glass flakes. Layered silicates such as montmorillonite are preferred, and dispersion methods thereof include, for example, extrusion kneading and mixing into resin solutions. A conventionally known method such as a dispersion method can be used. Examples of methods for imparting oxygen scavenging functions include hindered phenols, vitamin C, vitamin E, organic phosphorus compounds, gallic acid, pyrogallol and other low molecular organic compounds that react with oxygen, cobalt, manganese, nickel, iron And a method of using a composition containing a transition metal compound such as copper at least in part.
The thickness of the material such as these films is practically about 10 to 300 μm, preferably about 10 to 100 μm, and in the case of a plastic film, it may be uniaxially or biaxially stretched. Various surface treatments such as flame treatment and corona discharge treatment may be performed on the surface of the film.

  Furthermore, when the multilayer structure is used as a packaging material such as a pouch or a lid, a layer having a role of a sealant may be laminated. The thermoplastic resin that can be used as a sealant is not particularly limited as long as it can exhibit the role as a sealant. For example, polyethylenes such as low density polyethylene, medium density polyethylene, and high density polyethylene, propylene homopolymer, propylene -Polypropylenes such as ethylene block copolymer, propylene-ethylene random copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer Polyolefins such as polymers, propylene-α-olefin copolymers, polybutene, polypentene, and ionomer resins, polyester resins such as polystyrene and polyethylene terephthalate, and heat peelable with easy peel properties Sexual resins. The sealant layer may be a single layer made of the above resin or may have a multilayer structure of two or more layers. In the case of a multilayer structure, an adhesive resin layer made of a modified polyolefin resin or the like may be laminated between the resin layers as necessary.

  For the sealant layer, impact modifiers such as various elastomers, crystal nucleating agents, fatty acid amides, fatty acid metal salts, fatty acid amides, and other lubricants, copper compounds, as long as the ability as a sealant is not impaired , Organic or inorganic halogen compounds, hindered phenols, hindered amines, hydrazines, sulfur compounds, phosphorous compounds such as sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, magnesium hypophosphite, etc. Antioxidants, heat stabilizers, anti-coloring agents, UV absorbers such as benzotriazoles, release agents, additives such as plasticizers, coloring agents, flame retardants, organic pigments such as inorganic pigments and dyes such as titanium oxide A pigment may be included.

  The thickness of the sealant layer is about 10 to 300 μm, preferably about 10 to 100 μm, and the surface of the film may be subjected to various surface treatments such as flame treatment and corona discharge treatment.

  The surface of the outer layer and inner layer of the film may be subjected to a printing process. When printing processing is performed, general printing equipment that has been used for printing on a conventional thermoplastic resin film such as a gravure printing machine, a flexographic printing machine, and an offset printing machine can be similarly applied. In addition, the ink for forming the printing layer is formed from pigments such as azo and phthalocyanine, resins such as rosin, polyamide resin and polyurethane, solvents such as methanol, isopropyl alcohol, ethyl acetate, propyl acetate and methyl ethyl ketone. The ink used for the printing layer to the conventional thermoplastic resin film may be applied similarly.

In the present invention, the adhesive application surface may form a primer (medium) layer. In that case, as long as it has adhesiveness with the substrate, primers having various chemical structures can be used for both one-part and two-part systems, and preferably used as a main solvent for the adhesive, such as methanol. A polyester primer with low alcohol permeability is practical. The thickness of the primer layer is 0.01 to 20 μm, preferably 0.1 to 5 μm. If it is this range, sufficient adhesiveness can be exhibited with uniform thickness.

Examples of the laminate constituting at least a part of the multilayer structure of the present invention include, for example, (layer 1) / (layer 2) / sealant layer, nylon layer / (layer 1) / (layer 2), (layer 1) ) / Nylon layer / (layer 2), (layer 1) / nylon layer / (layer 2) / polyester layer, nylon layer / (layer 1) / (layer 2) / sealant layer, (layer 1) / (layer 2) ) / Polyester layer, (layer 1) / (layer 2) / polyolefin layer, polyolefin layer / (layer 2) / (layer 1) / (layer 2) / sealant layer and the like, but are not limited thereto. These laminates may include other layers as long as the above-described layers are laminated in this order. The nylon layer (a layer mainly composed of polyamide resin), the polyester layer (a layer mainly composed of polyester resin), and the polyolefin layer (a layer mainly composed of polyolefin). . In addition, it is preferable that (layer 1) exists in the content side of the laminated body containing the structure of (layer 2) / (layer 1). In the laminate including the configuration of (layer 2) / (layer 1) / (layer 2), the (layer 2) thickness on the content side is preferably thinner than the (layer 2) thickness on the outer layer side. By doing so, oxygen from the contents can be efficiently absorbed while preventing oxygen from flowing in from the atmosphere, and the expiration date of the contents can be extended.

The multilayer structure of the present invention can be used as a packaging material such as a four-side sealed bag, a bag of various pillow bags, a standing pouch, and a lid for a container from a substantially unstretched film. it can. Furthermore, a container can also be manufactured after manufacturing a stretched film by using a multilayer film as an original fabric. A stretched film and an unstretched film can also be laminated and used. A multilayer unstretched film can be thermoformed into a cup-shaped container. Further, it may be laminated with paper to form a multilayer container. Various articles can be stored and stored in the multilayer container of the present invention. For example, carbonated drinks, juice, water, milk, sake, whiskey, shochu, coffee, tea, jelly drinks, health drinks and other liquid drinks, seasonings, sauces, soy sauce, dressings, liquid dashi, mayonnaise, miso, grated spices Seasonings such as jams, creams, chocolate pastes and other paste-like foods, liquid soups, boiled foods, pickles, stewed and other liquid processed foods such as buckwheat noodles, noodles, ramen and other raw noodles and boiled noodles , Representatives of pre-cooked rice such as polished rice, moistened rice, and non-washed rice, cooked cooked rice, processed rice products such as gomoku rice, red rice, rice bran, powdered soup, and powdered seasonings such as dashi stock High-moisture foods, dairy products such as cheese and yogurt, other solid and solution chemicals such as pesticides and insecticides, liquid and paste pharmaceuticals, lotions, cosmetic creams, and cosmetic emulsions Hair dressing, it is possible to house a hair dye, shampoo, soap, detergent or the like, various articles.

  In particular, the multilayer structure of the present invention is used as a material for packaging containers that contain articles with high water activity, packaging containers that are exposed to high humidity, and packaging containers that are subjected to heat sterilization treatment such as retort and boiling. It is suitable.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. The gas barrier properties and transparency were evaluated by the following methods.
(1) The oxygen permeability (OTR) of the film was measured in accordance with ASTM D3985 in an atmosphere having a gas barrier property of 23 ° C. and a relative humidity of 60% RH. The prepared film was promptly placed on OX-TRAN 2/20 manufactured by Modern Controls and measured. The lower the value, the better the oxygen barrier property. When installing the film in the apparatus, oxygen gas was circulated on the (layer 2) side, and a nitrogen / hydrogen mixed gas was circulated on the (layer 1) side.
(2) Transparency The haze (cloudiness value) of the film was measured according to ASTM D1003 in an atmosphere of 23 ° C. and a relative humidity of 60% RH. The measuring instrument used is a fog value measuring device (model: COH-300A) manufactured by Nippon Denshoku Industries Co., Ltd.
(3) Strength OTR measurement The strength of the film after 2 months was evaluated. Those having practically sufficient strength were rated as “◯” and those not brittle, such as brittle, as “poor”.

<Epoxy resin curing agent a>
A reaction vessel was charged with 1 mole of metaxylylenediamine. The temperature was raised to 60 ° C. under a nitrogen stream, and 0.93 mol of methyl acrylate was added dropwise over 1 hour. After completion of the dropwise addition, the mixture was stirred at 120 ° C. for 1 hour, and further heated to 160 ° C. in 3 hours while distilling off generated methanol. The mixture was cooled to 100 ° C., and a predetermined amount of methanol was added so that the solid content concentration became 70% by weight to obtain an epoxy resin curing agent a. The content of amide groups in the epoxy resin curing agent a was 21% by weight.

<Master batch b>
Nylon MXD6 (Mitsubishi Gas Chemical Co., Ltd. MX nylon 6007, hereinafter abbreviated as MX nylon) and cobalt stearate, which were polycondensed with metaxylylenediamine and adipic acid, were dry blended at a ratio of 95.8: 4.2 (% by weight). Thereafter, the mixture is supplied to a co-rotating twin screw extruder having a screw diameter of 35 mmφ equipped with a strand die, melt kneaded at an extruder temperature of 260 ° C., the strand is extruded from the strand die, air cooled, and then pelletized. A master batch b having a cobalt metal atom concentration of 0.4% by weight was obtained by pelletization.

<Single layer film c>
MX nylon (MX Nylon 6007 manufactured by Mitsubishi Gas Chemical Co., Ltd.) and masterbatch b are dry blended with a tumbler at a ratio of 90:10 (% by weight), and this is a screw diameter provided with a T die, cooling roll, take-up machine, etc. It was put into a hopper of a 25 mmφ single screw extruder, melt kneaded at an extruder temperature of 260 ° C., and then formed into a film to obtain a single layer film having a cobalt metal atom concentration of about 400 ppm and a thickness of 135 μm. The obtained single-layer film was heated with a biaxial stretching apparatus under the conditions of a heater temperature of 105 ° C. and a preheating time of 30 seconds, stretched 3 (MD direction) × 3 (TD direction) times, and heated to 230 ° C. The film was heat-set in an electric furnace for 10 seconds to obtain a 15 μm stretched film (single layer film c). This film had a haze of 0.9% / μm and was excellent in transparency.

<Single layer film d>
A stretched film (single layer film d) having a thickness of 5 μm is formed in the same manner as the single layer film c, except that a single layer film having a thickness of 60 μm is stretched 4 (MD direction) × 3 (TD direction) times. Yeah. This film had a haze of 0.3% / μm and was excellent in transparency.

<Single layer film e>
Nylon MXD6 / MXDI obtained by polycondensation of metaxylylenediamine / adipic acid / isophthalic acid at a molar ratio of 100/95/5 (melting point: 232 ° C., sodium hypophosphite compound, phosphorus atom concentration: 100 ppm) Is used in place of MX nylon, and a single layer film having a thickness of 120 μm is stretched to 3.5 (MD direction) × 3.4 (TD direction) times in the same manner as the single layer film c, A stretched film (single layer film e) having a thickness of 10 μm was obtained. The film had a haze of 0.6% / μm and was excellent in transparency.

<Single layer film f>
MX nylon (Mitsubishi Gas Chemical Co., Ltd. MX nylon 6007), nylon 6I / 6T (Mitsubishi Engineering Plastics grade: Novamid X21F07), and masterbatch b are dried in a tumbler at a ratio of 75: 20: 5 (weight%). A stretched film (monolayer film f) having a thickness of 8 μm was obtained in the same manner as the monolayer film d, except that blending was performed and the cobalt metal atom concentration was about 200 ppm. The film had a haze of 0.6% / μm and was excellent in transparency.

<Example 1>
Methanol / ethyl acetate containing 9 parts by weight of epoxy resin having a glycidylamine moiety derived from metaxylylenediamine (Mitsubishi Gas Chemical Co., Ltd .; TETRAD-X) and 146 parts by weight of epoxy resin curing agent a = 9 / One solution (solid content concentration: 35% by weight) was prepared, and 0.4 parts by weight of an acrylic wetting agent (BIC Chemie; BYK381) and a silicon antifoaming agent (BIC Chemie; BYK065) were prepared there. 0.05 parts by weight) and stirred well to obtain an adhesive (coating solution) having a Zahn cup (No. 3) viscosity of 14 seconds (25 ° C.).
This coating solution was applied to a single layer film c with a bar coater No. 6 (application amount: 3.5 g / m ² (solid content)), dried at 85 ° C. for 10 seconds, and then a 40 μm-thick linear low-density polyethylene film is bonded by a nip roll. A laminated film I was obtained by aging at 4 ° C. for 4 days. The content of the skeleton structure of the formula (1) in the adhesive layer (cured epoxy resin) was 62.0% by weight. Moreover, the thickness of the adhesive layer was 3.5 μm. Table 1 shows the OTR evaluation results of the film. Moreover, the film after OTR measurement had practically sufficient strength.

(Measurement of oxygen permeability coefficient of adhesive layer)
In order to measure the oxygen transmission coefficient of the adhesive layer, a laminated film was obtained in the same manner as in Example 1 except that a 40 μm linear low density polyethylene film was used instead of the single layer film c. The laminated film had an oxygen transmission rate (immediately after production) of 8.8 cc / (m ² · day · atm). Using the following formula, the oxygen transmission coefficient of the adhesive layer was determined to be 0.03 cc · mm / (m ² · day · atm).
1 / R = 1 / R _n (n = 1,2, ..) + DFT / P
Where R = oxygen permeability of the laminate (cc / (m ² · day · atm))
Rn (n = 1,2, ..) = Oxygen permeability of each substrate film (cc / (m ² · day · atm))
DFT = Adhesive layer thickness (mm)
P = oxygen permeability coefficient of adhesive layer (cc · mm / (m ² · day · atm))

<Example 2>
A laminated film II was obtained in the same manner as in Example 1 except that the single layer film d was used instead of the single layer film c. Table 1 shows the OTR evaluation results of the film. Moreover, the film after OTR measurement had practically sufficient strength.

<Example 3>
A laminated film III was obtained in the same manner as in Example 1 except that the single layer film e was used instead of the single layer film c. Table 1 shows the OTR evaluation results of the film. Moreover, the film after OTR measurement had practically sufficient strength.

<Example 4>
Methanol / ethyl acetate containing 9 parts by weight of epoxy resin having a glycidylamine moiety derived from metaxylylenediamine (Mitsubishi Gas Chemical Co., Ltd .; TETRAD-X) and 146 parts by weight of epoxy resin curing agent a = 9 / One solution (solid content concentration: 35% by weight) was prepared, and 0.4 parts by weight of an acrylic wetting agent (BIC Chemie; BYK381) and a silicon antifoaming agent (BIC Chemie; BYK065) were prepared there. ), 0.05 part by weight, 4.75 parts by weight of a silane coupling agent (manufactured by Chisso Corporation; Silaace S330 (3-aminopropyltriethoxysilane)) was added and stirred well, and the Zahn cup (No. 3) viscosity was added. An adhesive (coating solution) for 14 seconds (25 ° C.) was obtained.
This coating solution was applied to a single layer film f with a bar coater no. 5 (coating amount: 2.0 g / m ² (solid content)), dried at 85 ° C. for 10 seconds, and then a stretched polyester film having a thickness of 12 μm was bonded by a nip roll, and 4 at 40 ° C. A laminated film IV was obtained by aging for a day. The content of the skeleton structure of the formula (1) in the adhesive layer (cured epoxy resin) was 62.0% by weight. Moreover, the thickness of the adhesive layer was 2.0 μm. Table 1 shows the OTR evaluation results of the film. Moreover, the film after OTR measurement had practically sufficient strength.

<Comparative Example 1>
An ethyl acetate solution containing 50 parts by weight of a main agent made of polyurethane resin (manufactured by Toyo Morton Co., Ltd .; TM-329) and 50 parts by weight of a curing agent made of polyisocyanate resin (manufactured by Toyo Morton Co., Ltd .; CAT-8B) ( (Solid content concentration: 25% by weight) was prepared and stirred well to obtain a coating solution. A laminated film V was obtained in the same manner as in Example 1 except that this coating solution was used. Table 1 shows the OTR evaluation results of the film. Moreover, the film after the OTR measurement was brittle and did not have a practically sufficient strength.

<Comparative example 2>
As in Example 1, the coating solution was applied to a linear low density polyethylene film having a thickness of 40 μm and a bar coater No. 6 was applied using (coating amount: 3.5 g / ^{m 2} (solid content)), dried 10 seconds at 85 ° C., further laminating a linear low density polyethylene film having a thickness of 40μm by a nip roll, A laminated film VI was obtained by aging at 40 ° C. for 4 days. The content of the skeleton structure of the formula (1) in the adhesive layer (cured epoxy resin) was 62.0% by weight. Moreover, the thickness of the adhesive layer was 3.5 μm. Table 1 shows the OTR evaluation results of the film.

As shown in the above examples, a multilayer structure that satisfies the constituent requirements of the present invention has good gas barrier properties and strength for a long time, whereas a multilayer structure that does not satisfy specific conditions is It was inferior in strength.

Claims (10)

Polyamide obtained by polycondensation of a diamine component containing 70 mol% or more of metaxylylenediamine and a dicarboxylic acid component containing 50 mol% or more of an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms (A ) And a metal compound (B) containing one or more metal atoms selected from the group consisting of group VIII transition metals of the periodic table, manganese, copper and zinc ( A multilayer structure in which at least a part is formed of a laminate composed of at least two layers of a layer 1) and a layer (layer 2) mainly composed of a gas barrier adhesive resin (C). The multilayer structure according to claim 1, wherein the metal compound (B) is contained in an amount of 10 to 1000 ppm as a metal atom with respect to the polyamide (A). The multilayer structure according to claim 1, wherein the gas barrier adhesive resin (C) is mainly composed of a cured epoxy resin and / or a cured polyurethane resin. The gas barrier adhesive resin (C) is, the oxygen permeability coefficient ^{1.0ml · mm / m 2 · day} · MPa (23 ℃, 60% RH) multi-layer structure of claim 1 having the following oxygen barrier properties. The multilayer structure according to claim 1, wherein the gas barrier adhesive resin (C) comprises a cured epoxy resin containing 40% by weight or more of the skeleton structure of the formula (1).

The layered product according to any one of claims 1 to 5, wherein at least three layers of (layer 1) / (layer 2) / (layer mainly composed of polyester resin) are laminated in this order. Multi-layer structure. The layered product according to any one of claims 1 to 5, wherein at least three layers of (layer 1) / (layer 2) / (layer mainly composed of polyolefins) are laminated in this order. Multi-layer structure. 6. The laminate according to claim 1, wherein at least three layers of (layer mainly composed of polyamide resin) / (layer 1) / (layer 2) are laminated in this order. Multi-layer structure. The multilayer structure according to claim 1, wherein at least three layers of (layer 2) / (layer 1) / (layer 2) are laminated in this order. The multilayer structure according to any one of claims 1 to 9, wherein (Layer 1) is stretched.