JP2001138459A - Gas barrier laminated polyamide film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas barrier laminated polyamide film which shows high gas barrier properties, outstanding resistance to flex fatigue and transparency and is capable of preventing the contents of a package from suffering change of properties and discoloration when the film is used as various kinds of packaging materials and thereby protecting the contents against impacts or the like during conveyance. SOLUTION: The layer A is composed of a mixed polymer(a-3) of 70 wt.% or more polyamide polymer(a-1) containing a methaxylylene group comprising a methaxylylene diamine or a mixed xylylene diamine made up of the methaxylylene diamine and a paraxylylene diamine as a principal diamine, a 6-12C α,ω-aliphatic dicarboxylic acid as a principal dicarboxylic acid and 30 wt.% or less miscible polymer(a-2) having a melt point of 160 deg.C or more, a melt point difference of 50 deg.C or less from the polyamide polymer(a-1) containing the methaxylylene group and a glass transition point of 60 deg.C or less. The layer B composed of a mixed polymer(b-3) of 99-80 wt.% aliphatic polyamide(b-1) and 1-20 wt.% elastomer(b-2) is laminated on at least one of the faces of the layer A to form the gas barrier laminated polyamide film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide-based laminated film, and more particularly, to a polyamide film having an inorganic oxide vapor-deposited layer formed thereon. Especially when used as a packaging material for hydrated packaging, it is effective in preventing deterioration and discoloration of the contents, and in preventing bag breakage due to impact during transportation, etc., and is a gas barrier suitable for various packaging applications. The present invention relates to a functional laminated polyamide film.

[0002]

2. Description of the Related Art Conventionally, a film made of a polyamide containing xylylenediamine as a constituent component has excellent gas barrier properties and heat resistance as compared with films made of other plastics, and further has a film with a high breaking strength and a Young's modulus. It has the property of being strong. On the other hand, unstretched films or stretched films made of aliphatic polyamides, such as nylon 6 and nylon 66, are widely used as various packaging materials.

However, when the former film made of xylylenediamine as a component is used as a bending fatigue-resistant packaging material, the film may be bent in a processing step such as vacuum packaging or in the transportation of goods. There is a problem that pinholes occur due to fatigue fracture. If pinholes are generated in the packaging material of the product, the content is contaminated, rot or mold is generated, and the content is leaked, which leads to a reduction in the value of the product.

On the other hand, the latter film made of an aliphatic polyamide has excellent film strength such as bending fatigue resistance and impact resistance, but has a drawback that gas barrier properties are inferior.

[0005] Therefore, in order to impart gas barrier properties to a film made of an aliphatic polyamide, a polyvinylidene chloride polymer latex is coated on the film surface.

[0006] However, this coated film has a disadvantage that it becomes cloudy due to hot water treatment, and furthermore, there is a possibility that components which are toxic to humans such as dioxin are generated when the used film is incinerated. It has been pointed out that environmental pollution has become a major problem.

In order to solve the above problems, a method of mixing a polyamide polymer containing xylylenediamine as a constituent component with an aliphatic polyamide in an arbitrary ratio to form a film (Japanese Patent Publication No. 51-29192), A method in which each polyamide is melt-extruded with a separate extruder and laminated.
281889) and the like have been proposed.

However, even in these methods,
As for gas barrier properties, under high humidity atmosphere, the gas barrier properties decrease, and the gas barrier properties do not reach the polyvinylidene chloride polymer latex coated product, and it is also required as a packaging film for bending fatigue resistance and transparency. The film has not yet reached a satisfactory level in that it has excellent film characteristics.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional laminated polyamide film, and is excellent in gas barrier properties, flex fatigue resistance and transparency, which are the film properties required as a packaging film. When used as various packaging materials, it prevents deterioration and discoloration of the contents, and further protects the contents from impact during transportation, etc., and has excellent visibility of the contents. An object is to provide a laminated polyamide film having a suitable high gas barrier property.

[0010]

In order to achieve the above object, the gas-barrier laminated polyamide film of the present invention mainly comprises meta-xylylenediamine or a mixed xylylenediamine comprising meta-xylylenediamine and para-xylylenediamine. Diamine component, carbon number 6 ~
A meta-xylylene group-containing polyamide polymer (a-1) containing at least 12 α, ω-aliphatic dicarboxylic acid as a main dicarboxylic acid component and having a melting point of 160 ° C. or more, and the meta-xylylene group-containing polyamide polymer (A-
A layer comprising a mixed polymer (a-3) with a compatible polymer (a-2) having a melting point difference of not more than 50 ° C. and a glass transition point of not more than 60 ° C. and not more than 30% by weight On at least one side of the aliphatic polyamide (b-1) 99-80% by weight
And a layer B comprising a mixed polymer (b-3) of 1 to 20% by weight of an elastomer (b-2) and an elastomer (b-2) is laminated on at least one surface of the laminated polyamide film,
A gas-barrier laminated polyamide film, wherein an adhesion-modified layer and further an inorganic thin film layer as a gas barrier layer are formed thereon.

The polyamide-based laminated film of the present invention has excellent gas barrier properties, resistance to bending fatigue and transparency, and prevents deterioration and discoloration of the contents when used as various packaging materials. Further, the contents can be protected from impacts during transportation.

In this case, the laminated polyamide film contains metaxylylenediamine or a mixed xylylenediamine composed of metaxylylenediamine and paraxylylenediamine as a main diamine component and has 6 carbon atoms.
99 to 80 weight of an aliphatic polyamide (b-1) on at least one surface of the layer A composed of a metaxylylene group-containing polyamide polymer (a-1) having α, ω-aliphatic dicarboxylic acid as a main dicarboxylic acid component. % Of a mixed polymer (b-3) of 1% to 20% by weight of an elastomer (b-2).

In this case, the elastomer (b-
(B) a hard segment composed of a polyamide component selected from the group consisting of (a) a lactam ω-aminoaliphatic carboxylic acid aliphatic diamine and an aliphatic dicarboxylic acid; an aliphatic diamine and an aromatic dicarboxylic acid; It can be a polyamide-based block copolymer composed of a soft segment constituted by a polyoxyalkylene glycol component.

Further, in this case, the inorganic thin film layer can be made of a mixture of silicon oxide and aluminum oxide.

Further, in this case, the adhesion-modified layer is formed by coating an unstretched or uniaxial coating solution containing at least one of a polyester resin, an acrylic resin, a urethane resin and a copolymer resin thereof. After being applied to a stretched film and dried, the film can be formed by further stretching the film uniaxially or more and then heat-setting.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the gas-barrier laminated polyamide film of the present invention will be described in detail.

The main diamine component is meta-xylylenediamine or a mixed xylylenediamine composed of meta-xylylenediamine and para-xylylenediamine used in the present invention, and α, ω-aliphatic dicarboxylic acid having 6 to 12 carbon atoms is mainly used. In the meta-xylylene group-containing polyamide polymer (a-1) as the dicarboxylic acid component, the amount of para-xylylenediamine is preferably 30 mol% or less of the total xylylenediamine. The formed structural unit is preferably at least 70 mol% or more in the molecular chain.

Examples of the metaxylylene group-containing polyamide polymer (a-1) used in the present invention include, for example, polymethaxylylene adipamide, polymethaxylylene pimeramide, polymetaxylylene belamid, polymetaxylylene aze Lamid, polymethaxylylene sebacamide,
Homopolymers such as poly (meta-xylylene dodecane diamide), and meta-xylylene / para-xylylene adipamide copolymer, meta-xylylene / para-xylylene pimeramide copolymer, meta-xylylene / para-xylylene belamid copolymer, and meta-xylylene Copolymers such as / paraxylyleneazeramide copolymer, metaxylylene / paraxylylene sebacamide copolymer, metaxylylene / paraxylylene dodecanediamide copolymer, and homopolymers or copolymers thereof Are partially aliphatic diamines such as hexamethylenediamine, alicyclic diamines such as piperazine, aromatic diamines such as para-bis (2-aminoethyl) benzene, aromatic dicarboxylic acids such as terephthalic acid, and ε-caprolactam. Lactam, aminoheptanoic acid Can ω- amino acids, and a copolymer such as obtained by copolymerizing an aromatic aminocarboxylic acid of para-amino benzoic acid.

Further, layer 3 of layer A of the laminated polyamide film
It has a melting point of 60 ° C. or more that can constitute 0% by weight or less, has a melting point difference of 50 ° C. or less from the metaxylylene group-containing polyamide polymer (a-1), and has a glass transition point of 60%. As the compatible polymer (a-2) having a temperature of not more than 0 ° C, many polymers can be exemplified, and aliphatic polyamides such as nylon 6, nylon 6.6, and nylon 6/10, and nylon 6/6. 6 copolymer, nylon 6 /
Aliphatic polyamide copolymers such as 6.10 copolymers and nylon 6.6 / 6/10 copolymers, ε-caprolactam as a main component, nylon salts of hexamethylenediamine and isophthalic acid, Typical examples include polyamides such as polyamide copolymers containing a small amount of aromatics obtained by copolymerizing nylon salts of xylylenediamine and adipic acid, polyesters, polyolefins, etc. It has compatibility with the containing polyamide polymer (a-1).
When there is compatibility, the transparency of the laminated polyamide film can be substantially maintained, and the haze value of the film is 10% or less.

When the polymer having a melting point of less than 160 ° C. is mixed with the meta-xylylene group-containing polyamide polymer (a-1), the formed biaxially stretched film is subjected to a heat treatment at a high temperature after stretching to give wrinkles or spots. , Heat fixing at a high temperature is difficult, while heat fixing at a low temperature causes an increase in hot water shrinkage, and a film having good dimensional stability cannot be obtained. Further, a meta-xylylene group-containing polyamide polymer (a
When the difference of the melting point from the above (-1) is larger than 50 ° C., the mixture of the polymer and the metaxylylene group-containing polyamide polymer (a-1) has an unstable kneading state at the time of melting, and surging is performed on the extruded sheet. It is not preferable because it occurs. Further, a polymer having a glass transition temperature higher than 60 ° C. has a poor effect of improving the bending fatigue resistance of the film when mixed with the metaxylylene group-containing polyamide polymer (a-1).

The molecular weights of the metaxylylene group-containing polyamide polymer (a-1) and the compatible polymer (a-2) are high enough to maintain a uniform film surface when the mixture is melted and extruded. It is set so as to give a melt viscosity, but since a too high molecular weight makes the extrusion operation difficult, usually a relative viscosity in the range of 1.8 to 4.0 is desirable.

When the miscible polymer (a-2) is mixed with the metaxylylene group-containing polyamide polymer (a-1), the proportion of the miscible polymer (a-2) in the mixed polymer (a-3) is as follows. The range of 2) is 30% by weight or less, preferably 1 to 30% by weight, particularly preferably 5 to 30% by weight. Mixing the compatible polymer (a-2) in an amount exceeding 30% by weight is not preferable because the effect of improving the bending fatigue resistance is not recognized, and the gas barrier properties and the yield point strength are further reduced.

The method of mixing the metaxylylene group-containing polyamide polymer (a-1) and the compatible polymer (a-2) is not particularly limited.
After mixing using a mold blender or the like, a method of melting and molding is used.

The polymer forming the layer A of the laminated polyamide film may contain other thermoplastic resins, if necessary, such as polyester-based polymers such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2,6-naphthalate. A polyolefin-based polymer such as coalesced polyethylene, polypropylene and the like may be contained within a range that does not impair the properties.

In the present invention, a mixed polymer (b-3) of 99 to 80% by weight of an aliphatic polyamide (b-1) and 1 to 20% by weight of an elastomer (b-2) is provided on at least one surface of the layer A. By laminating the layer B consisting of, it is possible to further improve the bending fatigue resistance without impairing the excellent gas barrier properties.

The mixed polymer (b-3) constituting the layer B is mixed with 99 to 80% by weight of the aliphatic polyamide (b-1) and 1 to 20% by weight of the elastomer (b-2).
If the amount of the elastomer (b-2) is less than 1% by weight, the effect of improving the bending fatigue resistance is small, and if it exceeds 20% by weight, the transparency of the film is undesirably reduced. A particularly preferable mixing ratio for balancing the bending fatigue resistance and the transparency of the film is 3 to 10% by weight.

Typical examples of the aliphatic polyamide (b-1) used in the present invention include nylon 6, nylon 6.6, nylon 12, and nylon 6.10. / 6/6, nylon 6/6/10, nylon 6.6 / 6/10, ε-
It is also possible to use a copolymer obtained by copolymerizing a small amount of a caprolactam as a main component, a nylon salt of hexamethylenediamine and isophthalic acid, or a nylon salt of metaxylylenediamine and adipic acid.

The elastomer (b-
As 2), polyamide-based block copolymers such as polyether amide, polyether ester amide, and polyester amide; and acrylates such as ethylene and methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate; Acrylic or methacrylic elastomers such as copolymers with methacrylic acid esters, ionomer resins, styrene elastomers and the like can be mentioned. Among them, the elastomer is preferably a polyamide-based block copolymer composed of a hard segment composed of a polyamide component and a soft segment composed of a polyoxyalkylene glycol component in terms of transparency, and the polyamide component of the hard segment is preferably Lactams, ω-amino aliphatic carboxylic acids, lactams such as ε-caprolactam, ω-amino acids such as aminoheptanoic acid, selected from the group consisting of aliphatic diamines and aliphatic dicarboxylic acids or aliphatic diamines and aromatic dicarboxylic acids. Examples thereof include aliphatic carboxylic acids, aliphatic diamines such as hexamethylenediamine, aliphatic dicarboxylic acids such as adipic acid, and aromatic dicarboxylic acids such as terephthalic acid. Examples of the polyoxyalkylene glycol constituting the soft segment of the polyamide-based block copolymer include polyoxytetramethylene glycol, polyoxyethylene glycol, and polyoxy-1,2-propylene glycol.

Also, an antistatic agent, an inorganic lubricant, an organic lubricant,
Various additives such as an antifogging agent, an antiblocking agent, a heat stabilizer, an ultraviolet absorber, a dye, and a pigment can be added to one or both of the A layer and the B layer as needed.

The thickness of the laminated polyamide film is not particularly limited, but when used as a packaging material, it is usually 100 μm or less, and generally 5 to 50 μm.
Is used.

The thickness ratio of the layer A and the layer B of the laminated film can be set according to the required gas barrier properties and flex fatigue resistance, and is not particularly limited.
In order to obtain a gas-barrier laminated polyamide film having an excellent gas barrier property for oxygen, the thickness of the A layer is usually
The thickness is set so as to be 40% or more of the total film thickness of the layer B and the layer B.

Further, the mixed polymer (b-3) of the layer B includes:
Other thermoplastic resins and various additives can be added, if necessary, in order to improve film properties required as a packaging material such as lubricity and antistatic properties.

The laminated polyamide film has an elastic recovery force under normal temperature or low temperature environment, and has excellent properties such as excellent impact resistance and bending fatigue resistance, as well as excellent transparency.
It has a good appearance even when formed into a printed film, and is a laminated film suitable as various packaging materials.

The above-mentioned laminated polyamide film can be produced by a known production method. For example, a method in which the polymers constituting each layer are melted using separate extruders and co-extruded from a single die, Any known method such as a method in which the polymers constituting each layer are separately melt-extruded into a film and then laminated by a lamination method, or a method in which these are combined, can be used.

Further, the laminated polyamide film may be an unstretched film layer or a stretched film layer, but each layer may have an oxygen gas barrier property and transparency, and furthermore, a processability of the film. In order to improve the film, it is preferable that the film is a laminated film obtained by stretching in a uniaxial or biaxial direction. As the stretching method, a known method such as a flat sequential biaxial stretching method, a flat simultaneous biaxial stretching method, and a tubular method can be used.

The adhesion modifying layer in the present invention is necessary for firmly adhering the laminated polyamide film and the inorganic thin film layer and obtaining higher quality reliability. A commonly used resin is a polyester resin, an acrylic resin, a urethane resin, or a coating liquid containing at least one of these copolymer resins as a main component, applied to an unstretched or uniaxially stretched film, and dried. Further, after the film is further stretched uniaxially or more, a high adhesive strength can be obtained by the adhesive modified layer formed by the in-line coating method formed by heat fixing.

The polyester resin used for the adhesion modifying layer is conventionally known and is not particularly limited. As the dicarboxylic acid component of the polyester resin, terephthalic acid, isophthalic acid, phthalic acid, 2,5-dimethylterephthalic acid,
1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-bisphenoxyethane-p,
p'-dicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid and the like and ester-forming derivatives thereof. As the glycol component of the polyester resin, ethylene glycol, 1,3-propanediol, 1,4-
Examples thereof include butanediol, neopentyl glycol, diethylene glycol, 1,4-cyclohexanedimethanol, and trimethylolpropane. Also,
In order to facilitate the water solubility of the polyester resin, it is preferable to copolymerize a compound containing a carboxylate group or a compound containing a sulfonic acid group. Examples of the compound containing a carboxylate group include trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, 4-methylcyclohexene-1,2,3-tricarboxylic acid, trimesic acid, 1,2,3 , 4-butanetetracarboxylic acid,
1,2,3,4-pentanetetracarboxylic acid, 3,
3 ′, 4,4′-benzophenonetetracarboxylic acid,
5, (2,5-dioxotetrahydrofurfuryl) -3
-Methyl-3-cyclohexene-1,2-dicarboxylic acid, 5- (2,5-joxotetrahydrofurfuryl)
-3-cyclohexene-1,2-dicarboxylic acid, cyclopentanetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, ethylene glycol visterimelli Tate, 2,2 ′, 3,3′-diphenyltetracarboxylic acid, thiophene-2,3,4,5-tetracarboxylic acid,
Examples include, but are not limited to, ethylene tetracarboxylic acid and the like, and alkali metal salts, alkaline earth metal salts, and ammonium salts thereof. Examples of the compound containing a sulfonic acid salt group include sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, sulfo-p-xylylene glycol, and 2-sulfophthalic acid. -1, 4
-Bis (hydroxyethoxy) benzene and the like, or alkali metal salts, alkaline earth metal salts, and ammonium salts thereof, but are not limited thereto.
Further, as the polyester resin, a modified polyester copolymer, for example, a block copolymer or a graft copolymer modified with acryl, urethane, epoxy or the like can be used.

Examples of the aqueous polyurethane resin used for the adhesion modifying layer include a polyurethane resin having an increased affinity for water with a carboxylic acid group, a sulfonic acid group or a half-sulfate group. Examples of the polyhydroxy compound used for the synthesis of the polyurethane resin include, for example, polyethylene glycol, polypropylene glycol, polyethylene / propylene glycol,
Polytetrapropylene glycol, hexamethylene glycol, tetramethylene glycol, 1,5-pentanediol, diethylene glycol, triethylene glycol, polycaprolactone, polyhexamethylene adipate, polyhexamethylene sebacate, polytetramethylene adipate polytetramethylene sebacate, Trimethylolpropane, trimethylolethane, pentaerythritol, glycerin and the like can be mentioned. Examples of the polyisocyanate compound include hexamethylene diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, isophorone diisocyanate, and adducts of tolylene diisocyanate and trimethylolethane. Examples of the carboxylic acid-containing polyol include dimethylolpropionic acid, dimethylolbutyric acid, dimethylolvaleric acid, and trimellitic acid bis (ethylene glycol) ester. Examples of the amino acid-containing carboxylic acid include β-aminopropionic acid, γ-aminobutyric acid, p-aminobenzoic acid, and the like. Examples of the hydroxyl group-containing carboxylic acid include 3-hydroxypropionic acid, γ-hydroxybutyric acid, p- (2
-Hydroxyethyl) benzoic acid, malic acid and the like. Examples of the compound having an amino group or a hydroxyl group and a sulfonic acid group include aminomethanesulfonic acid, 2-aminoethanesulfonic acid, 2-amino-5-methylbenzene-2-sulfonic acid, sodium β-hydroxyethanesulfonic acid, and fat. Examples include an addition product of an aliphatic di-primary amine compound with propane sultone and butane sultone, and preferably an addition product of an aliphatic di-primary amine compound with a propane sultone. Furthermore, examples of the compound containing an amino group or a hydroxyl group and a sulfuric acid half ester group include aminoethanol sulfate, aminobutanol sulfate, hydroxyethanol sulfate, α-hydroxybutanol sulfate, and the like.

Alternatively, JP-B-42-24194, JP-B-46-7720, JP-B-46-10193, JP-B-49-37839, JP-A-50-123197,
JP-A-53-126058, JP-A-54-13809
No. 8, for example, a polyurethane resin having an anionic group or a polyurethane resin according to them. Here, the main components of the polyurethane-forming component are a polyisocyanate, a polyol, a chain extender, a crosslinking agent, and the like. Moreover, molecular weight 300-2000
A resin comprising a compound having at least one polyol, polyisocyanate, a chain extender having a reactive hydrogen atom, an isocyanate group, and at least one anionic group is desirable. The anionic group in the polyurethane resin is preferably -SO3H, -OSO2H,-
COOH and their ammonium and lithium salts,
Used as sodium, potassium or magnesium salts.

The acrylic resin used for the adhesion modifying layer is:
Conventionally known ones are not particularly limited. Known monomers can be used as the monomer component constituting the acrylic resin. For example, alkyl acrylate, alkyl methacrylate (the alkyl group is a methyl group, an ethyl group, an n-propyl group, a t-butyl group, a 2-ethylhexyl group, a lauryl group, a stearyl group, a cyclohexyl group,
Phenyl, benzyl, phenylethyl, etc.), 2-
Hydroxyl group-containing monomers such as hydroxylethyl acrylate, 2-hydroxypropyl acrylate and 2-hydroxypropyl methacrylate, acrylamide, N
Amide group-containing monomers such as -methylacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N, N-dimethylolacrylamide, N-methoxymethylacrylamide, N-phenylacrylamide, N, N-diethylaminoethyl acrylate,
Amino group-containing monomers such as N, N-diethylaminoethyl methacrylate; epoxy group-containing monomers such as glycidyl acrylate and glycidyl methacrylate; and carboxyl groups such as acrylic acid, methacrylic acid and salts thereof (lithium salt, sodium salt, potassium salt, etc.). Or a monomer containing a salt thereof, and the like, and these are copolymerized using one kind or two or more kinds. Further, they can be used in combination with other types of monomers.

Examples of other types of monomers include epoxy group-containing monomers such as allyl glycidyl ether and sulfonic acids such as styrene sulfonic acid, vinyl sulfonic acid and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.). The group has a carboxyl group such as a monomer containing the salt thereof, crotonic acid, itaconic acid, maleic acid, fumaric acid and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.) or a salt thereof. Monomers, monomers containing acid anhydrides such as maleic anhydride and itaconic anhydride, vinyl isocyanate, allyl isocyanate, styrene, vinyl methyl ether, vinyl ethyl ether, vinyl trisalkoxysilane, alicyl maleic acid monoester, alkyl fumaric acid Monoester, Ac Ronitoriru, methacrylonitrile,
Examples thereof include alkyl itaconic acid monoester, vinylidene chloride, vinyl acetate, and vinyl chloride. Further, as the acrylic resin of the present invention, a modified polyester copolymer, for example, a block copolymer or a graft copolymer modified with acryl, urethane, epoxy or the like can be used.

The molecular weight of the acrylic resin of the present invention is preferably 100,000 or more, more preferably 300,000 or more, from the viewpoint of adhesion.

At least one of the above-mentioned polyester resins, acrylic resins, urethane resins, and copolymer resins thereof can form an adhesion-modified layer with the main component as it is, and further a crosslinking agent (curing resin) is used. By blending and curing, a high degree of adhesion can be imparted to the adhesion modified layer.

Examples of the crosslinking agent include a phenol formaldehyde resin obtained by condensing an alkylated phenol or cresol with formaldehyde; an adduct of urea, melamine, benzoguanamine or the like with formaldehyde, and the adduct having 1 to 1 carbon atom. An amino resin such as an alkyl ether compound composed of alcohol No. 6; a polyfunctional epoxy compound; a polyfunctional isocyanate compound; a blocked isocyanate compound; a polyfunctional aziridine compound; an oxazoline compound.

As the phenol formaldehyde resin, for example, alkylated (methyl, ethyl, propyl,
Isopropyl or butyl) phenol, p-tert
-Amylphenol, 4,4'-sec-butylidenephenol, p-tert-butylphenol, o-, m
-, P-cresol, p-cyclohexylphenol,
4,4′-isopropylidenephenol, p-nonylphenol, p-octylphenol, 3-pentadecylphenol, phenol, phenyl o-cresol, p
-Condensates of phenols such as phenylphenol and xylenol with formaldehyde.

Examples of the amino resin include methoxylated methylol urea, methoxylated methylol N, N-ethylene urea, methoxylated methylol dicyandiamide, methoxylated methylol melamine, methoxylated methylol benzoguanamine, butoxylated methylol melamine, butoxylated methylol benzoguanamine, and the like. And methoxylated methylolmelamine, butoxylated methylolmelamine, and methylolated benzoguanamine.

Examples of the polyfunctional epoxy compound include diglycidyl ethers of bisphenol A and oligomers thereof, diglycidyl ethers of hydrogenated bisphenol A and oligomers thereof, diglycidyl orthophthalate, diglycidyl isophthalate, and the like.
Diglycidyl terephthalate, diglycidyl p-oxybenzoate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, diglycidyl succinate, diglycidyl adipate, diglycidyl sebacate, ethylene Glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate ,
1,4-diglycidyloxybenzene, diglycidylpropylene urea, glycerol triglycidyl ether,
Examples include trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether, and triglycidyl ether of a glycerol alkylene oxide adduct.

As the polyfunctional isocyanate compound,
Low-molecular or high-molecular aromatic or aliphatic diisocyanates and trivalent or higher polyisocyanates can be used. Examples of the polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds. Further, an excess amount of these isocyanate compounds and a low-molecular active hydrogen compound such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, or polyester polyols, Examples thereof include a terminal isocyanate group-containing compound obtained by reacting a polymer active hydrogen compound such as ether polyols and polyamides.

The blocked isocyanate can be prepared by subjecting the above isocyanate compound and a blocking agent to an addition reaction by a conventionally known appropriate method. Examples of the isocyanate blocking agent include phenols such as phenol, cresol, xylenol, resorcinol, nitrophenol, and chlorophenol; thiophenols such as thiophenol and methylthiophenol; oximes such as acetoxime, methyl etiketoxime, and cyclohexanone oxime. Alcohols such as methanol, ethanol, propanol and butanol; halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol; t-butanol and t-
Tertiary alcohols such as pentanol; ε-caprolactam, δ-valerolactam, ν-butyrolactam, β
Lactams such as propyl lactam; aromatic amines; imides; active methylene compounds such as acetylacetone, acetoacetate ester, and malonic acid ethyl ester; mercaptans; imines; ureas; diaryl compounds; Can be mentioned.

These crosslinking agents can be used alone or in combination.
A mixture of more than one species can be used. The compounding amount of the crosslinking agent is at least one or more of a main resin 1 and a polyester resin, an acrylic resin, a urethane resin, and a copolymer resin thereof.
5 parts by weight to 40 parts by weight is preferable for 00 parts by weight. (1) When the crosslinking agent is water-soluble, it is directly dissolved or dispersed in an aqueous solvent solution or dispersion of the graft copolymer, or (2)
When the crosslinking agent is oil-soluble, there is a method of adding it to the reaction solution after the completion of the grafting reaction. These methods can be appropriately selected depending on the type and properties of the crosslinking agent. In addition, crosslinking agents include
A curing agent or accelerator can be used in combination.

Various surfactants, antistatic agents, inorganic lubricants, organic lubricants, antibacterial agents, photo-oxidation catalysts, ultraviolet absorbers, metal alkoxides, various types of surfactants, as long as the effects of the present invention are not impaired. An additive such as a coupling agent can be contained.

As the coating solution, an organic solvent solution or dispersion of a resin or the like constituting the adhesion modifying layer, or an aqueous solvent solution or aqueous solvent dispersion can be used. In particular, an aqueous solution or dispersion is preferable in that an organic solvent which is problematic for the environment is not used. The solid content of the resin in the organic solvent or the aqueous solvent is usually 1% by weight to 50% by weight, preferably 3% by weight to 30% by weight.

When the above coating solution is applied to an unstretched or uniaxially stretched base film substrate and then dried and stretched,
It is necessary to dry under the condition that the drying temperature after application does not affect the subsequent stretching. In the case of the base material in this case, the film is stretched by setting the moisture content to 1% or less, and then heat-set at 220 ° C. or higher, so that the coating film becomes strong, and the adhesion between the adhesion modified layer and the film base material is improved. Improve dramatically. For example, conventionally, the heat fixing zone has been heated by hot air, but the adhesive property is further improved by intensively heating the adhesion reforming layer by condensing IR. If the water content is 2% or more during stretching after drying, depending on the drying temperature, crystallization occurs and the crystallization becomes cheaper, and the flatness may be deteriorated or the stretchability may be impaired.

As a method for applying the coating solution to the base material to form the adhesion modified layer, a known coating method such as a gravure method, a reverse method, a die method, a bar method, and a dip method can be used.

The coating amount of the coating solution is 0.00
5 to 5 g / m ² , preferably 0.02 to 0.5 g / m ²
It is. If the coating amount is less than 0.005 g / m ² , sufficient adhesive strength with the adhesion modifying layer cannot be obtained. If it exceeds 5 g / m ² , blocking occurs and there is a practical problem. The preferable adhesive strength at this time is 100 g / 15 mm or more. The more preferable adhesion strength is 150 g / 15 mm or more, further preferably 200 g / 15 mm or more, and further preferably 250 g / 15 or more.

Before coating, the base film is subjected to a surface treatment such as corona treatment, flame treatment, electron beam irradiation, etc. in order to further improve the adhesiveness between the base film and the adhesion modified layer. Stretching further improves the adhesiveness.

The adhesion-modified layer of the laminated polyamide film of the present invention has good adhesion to various materials, but in order to further improve adhesion and printability, the adhesion-modified layer is further treated with corona and flame. Alternatively, a surface treatment such as electron beam irradiation may be performed.

Various methods have been proposed for the inorganic thin film layer formed on the adhesion modifying layer, and the method is not limited as long as the gas barrier property is imparted. For example, Japanese Patent Publication No. 51-48511 discloses that a surface of a synthetic resin
A gas barrier film on which y (for example, SiO ₂ ) is deposited has been proposed. The SiOx type (X = 1.3 to 1.8) having good gas barrier properties has a slightly brown coloring and insufficient transparency. Although those mainly composed of aluminum oxide can be found in JP-A-62-101428, there are problems that the gas barrier properties of oxygen are slightly inferior and that bending resistance cannot be obtained. In addition, Al ₂ O _3.
As an example of the SiO ₂ system, there is one proposed in Japanese Patent Application Laid-Open No. 2-194944, but it is a laminate of Al ₂ O ₃ and SiO ₂ , so that the apparatus becomes large-scale. Also,
Even these inorganic thin film-based gas barrier films are still inferior in gas barrier properties and bending resistance. That is, when used as a food packaging material, in order to have retort resistance, a certain amount or more (for example, 2000
Although the thickness of the thin film of Å) is required, there is a problem that it is better to be as thin as possible to improve the bending resistance. It requires attention. In this way, it has sufficient gas barrier properties of oxygen and water vapor,
There are very few transparent barrier layers having retort resistance and high flexibility, but there is no particular limitation as long as there is no practical problem. Only silicon oxide / aluminum oxide thin films have excellent gas barrier properties and retort resistance, high bending resistance, and excellent durability such as bending.

The silicon oxide / aluminum oxide thin film is made of silicon oxide.
Mixture of silicon and aluminum oxide, or compound
It is thought that it consists of. Silicon oxide here
Means Si, SiO, SiO_TwoAnd so on
It is considered that each content etc. in silicon oxide depends on the preparation conditions.
different. Aluminum oxide is Al, AlO, Al _Two
O_ThreeIt consists of a mixture of various aluminum oxides such as
In addition, each content ratio etc. in aluminum oxide is also prepared
Different. Aluminum oxide in inorganic thin film layer in the present invention
20% by weight or more and 99% by weight or less
And preferably not less than 5% by weight and not more than 45% by weight.
is there. Oxide in silicon oxide / aluminum oxide based deposited film
If the amount of luminium is less than 5% by weight, lattice defects in the deposited film will occur.
As a result, it becomes difficult to obtain sufficient gas barrier properties,
Oxide in silicon oxide-aluminum oxide based deposited film
When the amount of nickel exceeds 45% by weight, the flexibility of the film decreases.
The film breaks due to dimensional change during hot water treatment
And peeling) are likely to occur and the gas barrier properties decrease.
Problem, and it is no longer suitable for the purpose of the present invention.
You. In addition, the composition contains fine components within a range that does not impair the properties.
Including other ingredients in amounts (up to 3% of all ingredients)
Good. The thickness of the inorganic thin film layer is particularly limited.
Although not a thing, from the point of gas barrier properties and flexibility
Is preferably 10 to 5000 °, more preferably 5
0 to 2000 °, but the composition ratio in the inorganic thin film layer, and
And the thickness of the thin film according to the required quality for each application.
What is necessary is just to select the composition in an inorganic thin film layer.

The silicon oxide / aluminum oxide based thin film is formed by a PVD method (physical vapor deposition method) such as a vacuum vapor deposition method, a sputtering method, an ion plating method, or a CVD method.
A method (chemical vapor deposition) or the like is appropriately used. For example, in a vacuum evaporation method, Al ₂ O ₃ and SiO _{2 are} used as evaporation source materials.
₂ , a mixture of Al and SiO ₂ , and the like, and as a heating method, resistance heating, high-frequency induction heating, electron beam heating, or the like can be used. Also, as a reactive gas,
Oxygen, nitrogen, water vapor, or the like may be introduced, or reactive deposition using means such as ozone addition or ion assist may be used. The production conditions may be changed within a range that does not impair the object of the present invention, such as applying a bias to the substrate, increasing the substrate temperature, or cooling the substrate. The same applies to a production method other than the sputtering method or the CVD method.

The properties of the laminated polyamide film having gas barrier properties of the present invention were evaluated by the following measuring methods. (1) Oxygen Permeability (cc / m ² · 24 hrs · tm) Using an OX-TRAN TWIN manufactured by Modern Control Co., the measurement was carried out at a temperature of 20 ° C. and a relative humidity of 77%.

(2) Bending Fatigue Resistance (Number of Pinholes) The film was cut into a circular shape having a diameter of 150 mm,
Attach to the end of the glass tube of the bending machine. The bending machine sends and exhausts compressed air (pressurized 0.7 kg / cm ² ) (decompressed 760 mm).
Hg) alternately, giving the bag-shaped film bending fatigue at a rate of 7.5 times / min. 23 ° C, 65% relative humidity
Under the above environment, the bag-shaped film was subjected to 2000 times of bending fatigue, and the number of holes generated in the film was counted.

(3) Haze A haze meter S type manufactured by Toyo Seiki Seisaku-sho, Ltd. was used according to JIS K-7105.
It measured according to. Haze (%) = [Td (diffuse transmittance%) / Tt (total light transmittance%)] × 100

(4) Adhesive strength The laminated product was manufactured by Toyo Sokki Co., Ltd. “Tensilon UTM”.
2), the film was peeled off by 180 degrees, and the SS curve between the inorganic thin film layer and the polyamide film layer was measured and determined.

(4) Relative viscosity The relative viscosity was measured using an Ubbelose viscometer at a concentration of 1 g / dl and a temperature of 20 ° C. using 96% sulfuric acid.

[0066]

EXAMPLES The contents and effects of the present invention will be specifically described with reference to examples, but the present invention will be described. However, the present invention is not limited to the following examples unless departing from the gist thereof.

(Example 1) An unstretched sheet having the following structure was obtained using a co-extrusion T-die equipment of two types and three layers. B
In the configuration of layer / layer A / layer B, the total thickness of the unstretched sheet is 220 μm, and the thickness ratio of layer A to the total thickness is 70%. Composition constituting layer A: 90% by weight of polymethaxylylene adipamide (relative viscosity: RV = 2.1) and nylon 6
A composition constituting the layer B: 95% by weight of nylon 6 and 5% by weight of a copolymer of polylaurinlactam and polyether (Daiamide manufactured by Daicel Huls Co., Ltd.) The obtained unstretched sheet is stretched 3.6 times in the machine direction, and terephthalic acid / isophthalic acid / 5-sulfoisophthalic acid // ethylene glycol / 1,4-butanediol = 25 / An aqueous polyester resin copolymerized at 20/5 // 25/25 (weight ratio) was converted to a solid content of 10%.
A coating solution prepared by diluting with water: isopropyl alcohol = 9: 1 (weight ratio) was applied by a gravure coating method, dried at 80 ° C., and subsequently stretched 3.6 times in the horizontal direction. By heat setting at 225 ° C. and in a heat setting zone, a 17 μm laminated biaxially stretched film was obtained. The final coating agent application amount was 0.1 g / m ² . Further, an inorganic deposited layer was formed on the laminated biaxially stretched film by the following method. That is, SiO ₂ (purity;
99.9%) and particulate (about 3 to 5 mm) Al ₂ O ₃ , and these evaporation materials are heated and evaporated by an electron beam heating type vacuum evaporation apparatus, and the laminated biaxially stretched film is evaporated. It was set on an unwinding roll of the apparatus, and was run on an evaporation source to obtain a gas-barrier laminated polyamide film having an inorganic vapor-deposited layer formed thereon. Note that the evaporation material was not mixed, the inside of the hearth was partitioned into two by a carbon plate, and one electron gun was irradiated as a heating source in a time-division manner to obtain SiO ₂ and Al ₂ O _3.
Is deposited to a film thickness of 250 ° and an aluminum oxide content of 2
An 8% inorganic vapor deposition film was formed. The oxygen permeability, the number of pinholes, and the haze of the obtained laminated biaxially stretched film were measured. Table 1 shows the results.

(Example 2) A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. Composition constituting layer A: 70% by weight of polymetaxylylene adipamide (relative viscosity: RV = 2.1) and nylon 6
Was 30% by weight. The resulting biaxially stretched film was measured for oxygen permeability, number of pinholes, and haze. Table 1 shows the results.

Example 3 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. Composition constituting layer B: Mixed polymer comprising 93% by weight of nylon 6 and 7% by weight of a copolymer of polylaurin lactam and polyether (trade name: Diamide, manufactured by Daicel Huls Co., Ltd.) The oxygen permeability, the number of pinholes, and the haze of the axially stretched film were measured. Table 1 shows the results.

Example 4 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. Composition Constituting Layer A: Polymetaxylylene Adipamide (Relative Viscosity: RV = 2.1) Composition Constituting Layer B: 93% by weight of nylon 6 and copolymer of polylaurin lactam and polyether ( 7% by weight of a mixed polymer of Daicel Huls Co., Ltd. (trade name: Diamide) The oxygen permeability, the number of pinholes, and the haze of the obtained biaxially stretched film were measured. Table 1 shows the results.

(Example 5) A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. Styrene / n-
An aqueous acrylic resin obtained by copolymerizing butyl acrylate / 2-hydroxyethyl methacrylate at 50/27/23 (weight ratio) was mixed with water: isopropyl alcohol = 9: 1 (weight ratio) so that the solid content concentration became 10%. The diluted and prepared coating solution was applied.

Example 6 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. As an adhesion modifying layer, a water-based polyurethane resin coating solution (trade name: Hydran HW340, manufactured by Dainippon Ink and Chemicals, Inc.) was diluted with water: isopropyl alcohol = 9: 1 (weight ratio) to a solid concentration of 10%. The coating solution was adjusted. . The oxygen permeability, the number of pinholes, and the haze of the obtained biaxially stretched film were measured. Table 1 shows the results.

Example 7 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. The following resin was used as the adhesion modifying layer. A terephthalic acid / isophthalic acid / fumaric acid /
/ Ethylene glycol / neopentyl glycol = 50
75 parts of a copolymerized polyester resin having a weight average molecular weight of 15000, 56 parts of methyl ethyl ketone and 19 parts of isopropyl alcohol were added thereto, and heated and stirred at 75 ° C. to dissolve the resin. After the resin was completely dissolved, 15 parts of maleic anhydride was added to the polyester solution. Next, a solution prepared by dissolving 10 parts of styrene and 1.5 parts of azobisdimethylvaleronitrile in 12 parts of methyl ethyl ketone was dropped into the polyester solution at a rate of 0.1 ml / min, and stirring was further continued for 2 hours.
After sampling for analysis from the reaction solution, 5 parts of methanol was added. Next, 300 parts of water and 15 parts of triethylamine were added to the reaction solution, followed by stirring for 1 hour. Thereafter, the reactor internal temperature was raised to 100 ° C., and methyl ethyl ketone, isopropyl alcohol, and excess ammonia were distilled off to obtain a water-dispersed graft polymerization resin. This resin was diluted with water: isopropyl alcohol = 9: 1 (weight ratio) so that the solid content concentration became 10% to prepare a coating solution. The oxygen permeability, the number of pinholes, and the haze of the obtained biaxially stretched film were measured. Table 1 shows the results.

Comparative Example 1 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. Composition constituting layer A: polymetaxylylene adipamide (relative viscosity: RV = 2.1) Composition constituting layer B: nylon 6 Oxygen permeability, number of pinholes, and the like of the obtained biaxially stretched film. Haze was measured. Table 1 shows the results.

Comparative Example 2 A biaxially stretched film was obtained in the same manner as in Example 1 except that the description in Example 1 was changed as follows. The following compositions were used for both the A layer and the B layer. Composition Constituting Layer A and Layer B: Polymethaxylylene Adipamide (Relative Viscosity: RV = 2.1) The oxygen permeability, the number of pinholes, and the haze of the obtained biaxially stretched film were measured. Table 1 shows the results.

(Comparative Example 3) The oxygen permeability, the number of pinholes, and the haze of the biaxially stretched film obtained in the description of Example 1 without providing the adhesion modifying layer and the inorganic thin film layer were measured.
Table 1 shows the results.

Comparative Example 4 A biaxially stretched film was obtained in the same manner as in Example 1, except that the inorganic thin film layer was provided without providing the adhesion modifying layer. The oxygen permeability, the number of pinholes, and the haze of the obtained biaxially stretched film were measured. Table 1 shows the results.

[0078]

[Table 1]

[0079]

EFFECT OF THE INVENTION The gas-barrier laminated polyamide film of the present invention has excellent oxygen gas barrier properties, and also has bending fatigue resistance and transparency, which are particularly necessary for packaging materials, and is used for foods, pharmaceuticals, etc. It is a film suitable for various packaging applications.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 7/04 CFG C08J 7/04 CFGE (72) Inventor Haruo Okudaira 344 Maebata, Kizu, Oaza, Inuyama, Aichi Prefecture Inside the Toyobo Co., Ltd. Inuyama Plant (72) Inventor Shinichiro Okumura 344 Maehata, Otsu, Kizu, Inuyama-shi, Aichi Prefecture F-term in the Inuyama Plant of Toyobo Co., Ltd. CA42 CB06 DB53 EB01 EB02 EB22 EB35 EB38 4F006 AA38 AB24 AB35 AB37 AB55 AB74 AB76 BA01 BA05 CA07 DA01 4F100 AA00D AA19D AA20D AB33D AK25C AK41A AK41B AK41B AK41B JD02D JD03 JK04 JK10 JL11C JN01 JN28 YY00A

Claims (5)

[Claims] 1. A main diamine component comprising meta-xylylenediamine or a mixed xylylenediamine comprising meta-xylylenediamine and para-xylylenediamine,
A meta-xylylene group-containing polyamide polymer (a-1) containing an α, ω-aliphatic dicarboxylic acid having 6 to 12 carbon atoms as a main dicarboxylic acid component, having 70% by weight or more, a melting point of 160 ° C. or more, and The difference in melting point from the containing polyamide polymer (a-1) is 50 ° C or less, and
Compatible polymers having a glass transition temperature of 60 ° C. or lower (a-
2) An aliphatic polyamide (b-1) is formed on at least one surface of the layer A composed of the mixed polymer (a-3) with 30% by weight or less.
Adhering to at least one side of a laminated polyamide film, wherein a layer B comprising a mixed polymer (b-3) of 99 to 80% by weight and 1 to 20% by weight of an elastomer (b-2) is laminated. A gas-barrier laminated polyamide film comprising a modified layer and an inorganic thin film layer as a gas barrier layer formed thereon. 2. The layer A according to claim 1, wherein meta-xylylenediamine or a mixed xylylenediamine comprising meta-xylylenediamine and para-xylylenediamine is used as a main diamine component, and α, ω- having 6 to 12 carbon atoms. A gas-barrier laminated polyamide film comprising a metaxylylene group-containing polyamide polymer (a-1) containing an aliphatic dicarboxylic acid as a main dicarboxylic acid component. 3. The elastomer (b-2) according to claim 1,
A hard segment composed of a polyamide component selected from the group consisting of (a) a lactam ω-aminoaliphatic carboxylic acid aliphatic diamine and an aliphatic dicarboxylic acid; an aliphatic diamine and an aromatic dicarboxylic acid; A gas-blocking laminated polyamide film, which is a polyamide-based block copolymer comprising a soft segment constituted by an alkylene glycol component. 4. A gas-barrier laminated polyamide film, wherein the inorganic thin-film layer constituting the gas barrier layer according to claim 1 comprises a mixture of silicon oxide and aluminum oxide. 5. An adhesive-modified layer according to claim 1, wherein a coating liquid containing at least one of polyester resin, acrylic resin, urethane resin, and a copolymer resin thereof as a main component is unstretched or unstretched. After coating on uniaxially stretched film and drying,
The gas-barrier laminated polyamide film, wherein the film is further formed by uniaxially or more stretching, and then heat-setting.