JP3248448B2 - Gas barrier resin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a gas barrier resin film suitable for use as a packaging film for fresh foods, processed foods, pharmaceuticals, medical equipment, and electronic parts.
The film includes a sheet. More specifically, the present invention relates to a gas-barrier resin film which is excellent in oxygen barrier properties and moisture-proof properties even after boil treatment and retort treatment, which are important properties in these applications.

[0002]

2. Description of the Related Art In recent years, the packaging of foods has changed drastically due to changes in the distribution of foods and eating habits, and the characteristics required for packaging films have become increasingly severe. Deterioration of food quality due to the effects of temperature, moisture, oxygen, ultraviolet rays, and microorganisms such as bacteria and mold in the distribution and sales process is a serious problem not only in terms of sales loss but also in terms of food hygiene. In the past, antioxidants, preservatives, etc. were directly added to foods as a method of preventing such quality deterioration, but recently food additives have become strictly regulated from the standpoint of consumer protection. The situation is inevitable to reduce the amount. Under such circumstances, there is an increasing demand for a packaging film that has a low gas and moisture permeability and does not reduce the value as a food even by freezing, boiling, retorting, or the like.

[0003] That is, in packaging of fish meat, animal meat, shellfish and the like, it is important to suppress oxidation and deterioration of proteins and oils and fats, and to maintain taste and freshness. For that purpose, it is necessary to block the permeation of air using a packaging material having good gas barrier properties. In addition, by packing the product with a gas barrier film, the aroma of the contents is retained and the permeation of moisture is prevented, so that the moisture absorption is suppressed in the case of dry matter and the deterioration due to the volatilization of moisture is caused in the case of wet matter. And solidification are suppressed, and fresh flavor during packaging can be maintained for a long time.

[0004] For these reasons, kneaded products such as kamaboko, dairy products such as butter and cheese, miso, tea, coffee,
As a packaging film for confectionery such as ham / sausage, instant food, castella, biscuit, etc., the above-described oxygen barrier properties, moisture-proof properties, and fragrance retention properties are extremely important properties. Having these properties is not limited to food packaging films, but is also extremely important in medical products that require aseptic handling and electronic component packaging films that require rust prevention. .

[0005] As a film having excellent oxygen barrier properties, moisture-proof properties and fragrance retention properties, a film obtained by laminating a metal such as aluminum on a plastic film, or a film obtained by coating vinylidene chloride or an ethylene vinyl alcohol copolymer is known. Have been.

However, the above-mentioned aluminum laminate is
Although it is economical, has excellent oxygen barrier properties, moisture proofing properties, and fragrance retention properties, it is opaque, so the contents cannot be seen at the time of packaging, and it does not transmit microwaves, so the microwave oven cannot be used. was there.

[0007] Further, those coated with vinylidene chloride or ethylene vinyl alcohol copolymer can be obtained by using steam,
The gas barrier properties of oxygen and the like are not sufficient, and the decrease is remarkable especially in high-temperature treatment. Further, with respect to a film coated with vinylidene chloride, generation of chlorine gas at the time of incineration or the like is caused, and there is a concern about the influence on the global environment.

On the other hand, a gas barrier film in which an inorganic thin film layer of silicon oxide, aluminum oxide or the like is formed on a plastic film is also known. For example, Japanese Patent Publication No. 51-48551 proposes a gas barrier film in which SixOy (for example, SiO ₂ ) is vapor-deposited on a synthetic resin film as a gas barrier film whose contents can be viewed and a microwave oven can be used. However, a SiOx-based material (x = 1.3 to 1.8) having a good gas barrier property is slightly brown, and has insufficient transparency.

As a transparent gas barrier film, Japanese Patent Application Laid-Open No. Sho 62-101428 proposes a film in which a layer mainly composed of aluminum oxide is formed on a plastic film. However, the gas barrier property is insufficient, and the bending resistance (especially the gelling resistance) is insufficient.

Further, the conventional laminated film provided with an inorganic vapor-deposited layer of silica, alumina or the like does not always have sufficient film strength, and also has a problem that the oxygen barrier property after boil and retort and the moisture resistance are deteriorated. I have. Inorganic vapor deposition layers such as silica and alumina are made of polyester film (PE
T) is often deposited. For example, PET / deposited layer /
In the case of a structure such as an adhesive layer / stretched nylon (ONY) / adhesive layer / unstretched polypropylene (CPP), there is a problem that shrinkage of nylon deteriorates oxygen barrier properties and moisture resistance after boiling or retorting. , PET
It is customary to have a configuration such as / deposited layer / adhesive layer / PET / adhesive layer / unstretched polypropylene (CPP). However, in this configuration, the strength at the time of falling is insufficient. Thus, in the laminated film provided with the inorganic vapor-deposited layer, it was difficult to achieve both film strength, oxygen barrier properties after boiling and retorting, and moisture resistance.

Further, a film containing stretched nylon as a vapor deposition base material (Japanese Patent Publication No. 7-12649) and a nylon as a laminate (Japanese Patent Application Laid-Open No. 7-276571) has been proposed. Have. However, these methods are not suitable for practical use because the process of manufacturing and transporting and storing nylon is complicated. Japanese Patent Publication No. 7-12649 also discloses a nylon having a low shrinkage rate at the time of high-temperature treatment (the sum of the absolute values of the dimensional change rates in the vertical and horizontal directions in a heat treatment at 120 ° C. for 5 minutes is 2% or less). Proposed. However, the boiling and retort treatments, which are high-temperature hot water treatments, increase the shrinkage of nylon and cannot maintain good oxygen barrier properties and moisture-proof properties.

Furthermore, Japanese Patent Application Laid-Open No. 7-276571 proposes a film in which stretched nylon having a low shrinkage rate in hot water is laminated on an inorganic vapor deposition layer of a film having an inorganic vapor deposition layer and a base material layer. ing. However, it is necessary to laminate a low-shrinkage nylon layer separately from the sealant film, which complicates the process and leads to an increase in manufacturing cost.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to have excellent gas barrier properties and moisture proof properties, and to provide excellent gas barrier properties even after boil treatment or retort treatment. An object of the present invention is to provide a gas barrier film that does not impair gas barrier properties and moisture resistance.

[0014]

Means for Solving the Problems The present invention has the following features.
Have. (1) Polyamide film and inorganic vapor deposition layer
Is also a laminated gas barrier film, 95 ℃,
When the maximum shrinkage after boiling for 30 minutes is 3.5% or less
A gas barrier resin film, which is characterized in that: (2) Maximum shrinkage of polyamide film at 170 ° C
Stress is 900gf / mm ^Two The following (1)
Gas barrier resin film. (3) Heat treatment of the polyamide film at 170 ° C for 10 minutes
(1) wherein the maximum shrinkage after treatment is 3.5% or less.
Gas barrier resin film. (4) The polyamide film is unstretched.
Film (Tg + 10) ° C or more and (Tc + 20) ° C or less
After stretching 2.5 to 4.0 times in the machine direction at the temperature, (Tc
+20) ° C or higher and (Tc + 70) ° C or lower at a temperature of 1.1 to
2.9 times the front stage horizontal stretching, then (Tc + 70)
℃ (Tm-30) ℃ or less, total transverse stretching ratio
Was stretched in the subsequent stage so that the ratio became about 3.0 to 4.5 times.
Then, using a tenter, (Tm-30) ° C or more (Tm-1)
0) Perform a 0-10% relaxation heat treatment in the transverse direction at a temperature of
The gas barrier tree according to (3) above,
Grease film. (5) After the boil treatment at 95 ° C. for 30 minutes,
Adhesion strength measured in air with polyamide film
The gas according to the above (1), wherein the gas is 100 g / 15 mm or more.
Barrier resin film. (6) After the boil treatment at 95 ° C. for 30 minutes,
Adhesion strength measured in water with polyamide film
The gas burr according to the above (1), which is 50 g / 15 mm or more.
A resin film. (7) Between the polyamide film layer and the inorganic vapor deposited layer
According to the above (1), wherein the anchor coat layer is formed on
Gas barrier resin film. (8) The compressive modulus of the anchor coat layer at 40 ° C is
3.0 kgf / mm^Two The gas described in (7) above
Barrier resin film. (9) If the anchor coat layer is made of polyester resin or
Graft copolymer of polyester and acrylic polymer
The gas barrier resin according to the above (7), which is a layer containing
the film. (10) A sealant layer is further laminated on the inorganic vapor deposition layer
The gas barrier resin film according to the above (1). (11) Sealant layer is made of polyolefin resin film
Described in (10) above that satisfies the following conditions (a) to (c):
The gas barrier resin film described above. (a) The compression modulus at 95 ° C. is 8 kgf / mm^Two that's all
It is. (b) Vicat softening point is 145 ° C or less. (c) Polyamide film after boiled at 95 ° C for 30 minutes.
For a maximum shrinkage of the film
The maximum shrinkage of the gas barrier resin film after
It is less than 0%. (12) An adhesive layer is further provided between the inorganic vapor deposition layer and the sealant layer.
The formed gas barrier resin film according to the above (10)
Lum. (13) The compression elastic modulus of the adhesive layer at 40 ° C. is 8.8 kgf.
/ Mm^Two The gas barrier resin according to (12) above
the film. (14) The amount of oxygen permeation after boiled at 95 ° C for 30 minutes is 1
5cc / m^Two ・ Atm ・ day or less
The gas barrier resin film described above. (15) The amount of water vapor permeated after boiled at 95 ° C for 30 minutes
10g / m^Two The gas described in (1) above, which is not more than day
Barrier resin film. (16) 2 kgf / cm^Two For 1 second
After 90 ° peel test, peel strength
The temperature when it becomes 500g / 15mm or more is 160 ° C or less
The gas barrier resin film according to the above (1), which is: (17) Measured according to ASTM-D1893-67
The blocking resistance is 10 g / 20 mm or less.
The gas barrier resin film according to (1).

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The gas barrier resin film of the present invention is a film in which a polyamide-based film as a support and an inorganic vapor-deposited layer are at least laminated. A polyamide film is a film having high strength, particularly high strength when dropped.

(Polyamide-based film) The properties required for the gas barrier resin film of the present invention, that is, 95 ° C.
In order to satisfy the maximum shrinkage rate of 3.5% or less after the boil treatment for 30 minutes, the polyamide film used in the present invention must have a specific shrinkage stress and / or shrinkage rate. preferable. Specifically, 170 ° C
Maximum shrinkage stress at preferably 900 gf / mm ² or less, more preferably 400 gf / mm ² or less, particularly preferably not more than ^{200gf / mm 2, 170 ℃,} 10
The maximum shrinkage after heat treatment for one minute is preferably 3.5% or less, more preferably 1.5% or less, and particularly preferably 0.1% or less.
7% or less. In the present invention, the maximum shrinkage stress, the maximum shrinkage, respectively, the longitudinal direction of the circular sample, the lateral direction,
The maximum shrinkage stress and shrinkage in directions forming angles of 30 °, 45 °, and 60 ° with these directions. Further, in the present invention, the vertical direction refers to a film forming direction, and the horizontal direction refers to a direction perpendicular to the direction. When the maximum shrinkage stress or the maximum shrinkage of the polyamide film is out of the above range, the gas barrier resin film is heated at 95 ° C.
When boiled for 30 minutes, the polyamide-based film shrinks, cracking and peeling of the inorganic vapor-deposited layer may occur, and gas barrier properties may be reduced.

The material of the polyamide film used in the present invention is not particularly limited as long as it satisfies the above-mentioned shrinkage characteristics, and any of homopolyamide, copolyamide, a mixture thereof, or a crosslinked product thereof can be used.
For example, a homopolyamide, a copolyamide, a mixture thereof, or a crosslinked product thereof having an amide repeating unit represented by the following formula (I) or (II) can be given. —CO—R ₁ —NH— (I) —CO—R ₂ —CONH—R ₃ —NH— (II) (wherein R ₁ , R ₂ and R ₃ are the same or different Represents a linear alkylene, an aromatic ring, or an aliphatic alkyl group.)

Specific examples of preferred homopolyamides include polycaproamide (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-9-aminononanoic acid (nylon 9), and polyundecaneamide (nylon 1).
1), polylaurin lactam (nylon 12), polyethylene diamine adipamide (nylon 2,6), polytetramethylene adipamide (nylon 4,6), polyhexamethylene adipamide (nylon 6,6), poly Hexamethylene sebacamide (nylon 6,10), polyhexamethylene dodecamide (nylon 6,12), polyoctamethylene adipamide (nylon 8,6), polydecamethylene adipamide (nylon 10,6), Polydecamethylene sebacamide (nylon 10, 10), polydodecamethylene dodecamide (nylon 12, 12), metaxylene diamine-6 nylon (MXD6) and the like can be mentioned.

Specific examples of preferred copolyamides include caprolactam / laurin lactam copolymer, caprolactam / hexamethylene diammonium adipate copolymer, laurin lactam / hexamethylene diammonium adipate copolymer, hexamethylene diammonium adipate / Hexamethylene diammonium sebacate copolymer, ethylene diammonium adipate / hexamethylene diammonium adipate copolymer, caprolactam / hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer and the like can be mentioned.

In order to impart flexibility to the polyamide film, a plasticizer such as an aromatic sulfonamide, p-hydroxybenzoic acid, or an ester thereof may be added to the polyamide resin, or an elastomer component having a low elastic modulus may be used. And lactams and the like can also be blended. Examples of the elastomer component include an ionomer resin, a modified polyolefin resin, a thermoplastic polyurethane, a polyether block amide, a polyester block amide, a polyether ester amide elastomer, a polyester elastomer, a modified styrene thermoplastic elastomer, a modified acrylic rubber, and a modified acrylic rubber. And ethylene propylene rubber.

The above-mentioned shrinkage characteristic required for a polyamide-based film, that is, “the maximum shrinkage stress at 170 ° C. is 900
gf / mm ² or less ”and“ the maximum shrinkage after heat treatment at 170 ° C. for 10 minutes is 3.5% or less ”, for example, when a substantially unoriented polyamide resin film is stretched at an appropriate temperature and at a suitable temperature. It can be provided by a method of performing biaxial stretching at a magnification.

Specifically, [Tg (glass transition temperature) +
10] ° C. or higher and [Tc (crystallization temperature) +20] ° C. or lower, after stretching 2.5 to 4.0 times in the machine direction, and then successively performing two-stage transverse stretching at different temperatures. Is exemplified. In two-stage transverse stretching, (Tc + 20) ° C or more (T
(c + 70) ° C. or lower, and the pre-stage transverse stretching is performed at 1.1 to 2.9 times, and then at a temperature of (Tc + 70) ° C. or more and [Tm (melting temperature) −30] ° C. or less, the total transverse stretching ratio is 3.
Later-stage transverse stretching is performed so as to be about 0 to 4.5 times. Then, using a tenter, (Tm-30) ° C or more (Tm-1)
0) Perform a 0-10% relaxation heat treatment in the transverse direction at a temperature of not more than 0 ° C. If such a method is adopted, the maximum shrinkage when heat-treated at 170 ° C. for 10 minutes can be suppressed to 3.5% or less. Also, after biaxial stretching, while relaxing in the longitudinal direction using multiple rolls and / or 60 to 100
Heat treatment with a humidified gas at a temperature of 170 ° C. can reduce the maximum shrinkage stress at 170 ° C. to 900 gf / mm ² or less.

In the above polyamide film, other additives such as a plasticizer, a heat stabilizer, an ultraviolet absorber, an antioxidant, a coloring agent, a filler, an antistatic agent, an antibacterial agent and a lubricant may be added, if necessary. It is also possible to blend an appropriate amount of an anti-blocking agent, another resin or the like. If necessary, an organic barrier layer (for example, composed of polyvinyl alcohol, ethylene-vinyl acetate copolymer, vinylidene chloride, or the like) may be laminated on the polyamide-based film by coating or co-extrusion. . Further, if necessary, another resin may be laminated by co-extrusion or the like, whereby another function can be newly provided.

The thickness of the polyamide film is preferably 1 to 300 μm, more preferably 10 to 100 μm. If the polyamide-based film is too thin, the film strength is reduced, and the bag is easily broken when dropped. If it is too thick, the processability is reduced, which is not preferable.

(Inorganic Vapor Deposition Layer) An inorganic vapor deposition layer is laminated on the polyamide film. This inorganic vapor-deposited layer imparts high gas barrier properties to the obtained gas barrier resin film. Materials for the inorganic vapor deposition layer having such an action include Al, Si, Ti, Zn, Zr,
Examples include metals such as Mg, Sn, Cu, and Fe, and oxides, nitrides, fluorides, sulfides, and the like of these metals. Specifically, SiOx (x = 1.0 to 2.0), alumina , Magnesia, zinc sulfide, titania, zirconia, cerium oxide, or a mixture thereof. The inorganic vapor deposition layer may be a single layer or a laminate of two or more layers.

The thickness of the inorganic vapor deposition layer is preferably 10
５5000 °, more preferably 50Å2000 °. If the film thickness is less than 10 °, sufficient gas barrier properties may not be obtained, which is not preferred. On the other hand, if it exceeds 5000 °, the effect corresponding thereto is not exhibited, the bending resistance is reduced, and the production cost is disadvantageous, which is not preferable.

As the method of forming the inorganic vapor-deposited layer, a known method, for example, a physical vapor-deposition method such as a vacuum vapor-deposition method, a sputtering method or an ion plating method, or a chemical vapor-deposition method such as a PECVD method is employed.

In the vacuum deposition method, metals such as aluminum, silicon, titanium, magnesium, zirconium, cerium, and zinc, and SiOx (x =
1.0-2.0), alumina, magnesia, zinc sulfide,
Compounds such as titania and zirconia and mixtures thereof are used. Heating methods include resistance heating, induction heating,
Electron beam heating or the like is employed. Further, as a reactive gas, oxygen, nitrogen, hydrogen, argon, carbon dioxide, water vapor, or the like may be introduced, or a reactive vapor deposition method using means such as ozone addition or ion assist may be employed. Further, a method of applying a bias to the polyamide-based film or heating and cooling the polyamide-based film may be employed. The above-described deposition material, reaction gas, bias application, and heating / cooling can be adopted also in a sputtering method and a CVD method.

(Anchor Coat Layer) The properties required for the gas barrier resin film of the present invention, that is, 95 ° C., 30 ° C.
In order to satisfy the maximum shrinkage rate of 3.5% or less after boiling for 5 minutes, the adhesion strength between the inorganic vapor-deposited layer and the polyamide-based film after boiling at 95 ° C. for 30 minutes was measured in air. Is 100 g / 15 mm or more, especially 150 g /
In addition, the adhesion strength between the inorganic vapor-deposited layer and the polyamide-based film measured in water after boil treatment at 95 ° C. for 30 minutes is 50 g / 15 mm or more, especially 9 mm or more.
It is preferably 0 g / 15 mm or more. As means for imparting such adhesion strength, corona treatment, flame treatment, low-temperature plasma treatment, glow discharge treatment, reverse sputtering treatment, rough surface treatment, or the like, before or during vapor deposition on the polyamide film. And a method of providing an anchor coat layer between the polyamide-based film layer and the inorganic vapor-deposited layer.

When the anchor coat layer is provided, the properties required for the gas barrier resin film of the present invention, that is, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes satisfy 3.5% or less. Preferably, the anchor coat layer has a specific compression modulus, and specifically, the compression modulus at 40 ° C. is preferably 3.0 kg.
f / mm ² or more, more preferably 5.0 kgf / mm ²
Above, particularly preferably 9.8 kgf / mm ² or more. By having such a compression elastic modulus, the heat shrinkage due to the boil treatment of the polyamide-based film is suppressed, and the heat shrinkage of the entire gas barrier resin film is reduced.

The material used for the anchor coat layer is not particularly limited as long as it satisfies the above-mentioned properties. For example, polyester resin, oil-modified alkyd resin, urethane alkyd resin, melamine alkyd resin, epoxy cured acrylic Resin, epoxy resin (cured by amine, carboxyl group-terminated polyester, phenol, isocyanate), isocyanate resin (amine,
(Curing with urea or carboxylic acid), urethane-polyester resin, polyurethane resin, phenol resin, polyester resin, polyamide resin, reactive acrylic resin, vinyl chloride resin and the like. Further, a resin obtained by solubilizing or dispersing these in water may be used.

Among the above-mentioned materials, polyester resins are preferred in that the adhesion between the polyamide-based film and the inorganic vapor-deposited layer and the gas barrier properties are maintained even after the boil treatment.
Alternatively, a graft copolymer of a polyester and an acrylic polymer is preferable. In the graft copolymer used in the present invention, the trunk polymer may be a polyester and the branch polymer may be an acrylic polymer, or the trunk polymer may be an acrylic polymer and the branch polymer may be a polyester. The ratio of the trunk polymer to the branch polymer in the graft copolymer is 5:95 to 95: 5, preferably 8 by weight.
0:20 to 20:80.

The molecular weight of the trunk polymer of the above graft copolymer is 5,000 to 200,000 in the case of polyester,
It is preferably 5000 to 50,000, and in the case of an acrylic polymer, 5000 to 200,000, preferably 5000 to 10
0000. The molecular weight of the branch polymer is 500 to 50,000 in the case of polyester, preferably 5,000 to 3,000.
0000, 500-500 for acrylic polymer
00, preferably 4000 to 50,000.

The glass transition point of this graft copolymer is 3
It is preferably 0 ° C or less, particularly preferably 10 ° C or less. When the glass transition point exceeds 30 ° C., peeling may occur between the anchor coat layer and the polyamide-based film.

Such a graft copolymer is, for example,
It can be produced by the following preparation methods (1) to (4), but is not limited to these methods.

(1) A radical, cationic or anionic polymerization initiation point is generated on the polyester molecule,
A method of graft-polymerizing a monomer containing at least an acrylic monomer by using this. According to this method, a graft copolymer in which the polyester is a trunk polymer and the acrylic polymer is a branch polymer is obtained.

In the graft copolymerization method, radicals are generated on polyester molecules by light, heat or radiation,
Next, a radical polymerization method for graft-polymerizing a monomer containing at least an acrylic monomer; AlCl
₃ , a cationic polymerization method in which cations are generated on polyester molecules using a catalyst of TiCl ₄ , and then a graft polymerization of a monomer containing at least an acrylic monomer is performed; anion is formed on polyester molecules using sodium metal, lithium metal, or the like; , And then an anionic polymerization method or the like in which a monomer containing at least an acrylic monomer is graft-polymerized.

(2) A polyester having a polymerizable unsaturated bond at the main chain, main chain terminal or side chain is prepared,
A method in which a monomer containing at least an acrylic monomer is graft-polymerized. According to this method, a graft copolymer in which the polyester is a trunk polymer and the acrylic polymer is a branch polymer is obtained.

As a method for preparing a polyester having a polymerizable unsaturated bond in the main chain, a method in which a dicarboxylic acid having a polymerizable unsaturated bond is copolymerized during the production of the polyester may be employed. As a method for preparing a polyester having a polymerizable unsaturated bond at the main chain terminal, a carboxyl group, an acid anhydride group,
A method of reacting a polymerizable monomer having a polymerizable unsaturated bond with a group capable of reacting with a hydroxyl group such as an acid chloride, an epoxy group, or an isocyanate group; a hydroxyl group, an amino group, an isocyanate group, etc. A method of reacting a polymerizable monomer having a polymerizable unsaturated bond with a functional group capable of reacting with a carboxyl group may be employed. As a method for preparing a polyester having a polymerizable unsaturated bond in a side chain, a carboxyl group or a hydroxyl group present in a polyester side chain portion has a functional group reactive with these groups and a polymerizable unsaturated bond. A method of reacting a polymerizable monomer having the following formula:

(3) A polyester having a functional group in a side chain and an acrylic polymer having a group reactive with the functional group at the polymer chain end, or an acrylic polymer having a functional group in a side chain and this functional group A method of directly reacting with a polyester having a reactive group at a polymer chain terminal. In the former method, a graft copolymer in which the polyester is a trunk polymer and the acrylic polymer is a branch polymer is obtained, and in the latter method, a graft copolymer in which the acrylic polymer is a trunk polymer and the polyester is a branch polymer is obtained. Can be

Examples of the functional group of the polyester side chain include a hydroxyl group and a carboxyl group. The group present at the terminal of the acrylic polymer and capable of reacting with the functional group includes a group capable of reacting with the hydroxyl group. For example,
Examples thereof include a carboxyl group, an acid anhydride group, an acid chloride group, an epoxy group, and an isocyanate group. Examples of the group that can react with the carboxyl group include an amino group and an isocyanate group. Examples of the functional group of the acrylic polymer side chain include a hydroxyl group, a carboxyl group, an acid anhydride group, an acid chloride group, an epoxy group, an amino group, and an isocyanate group.

(4) A polyester having a functional group in a side chain and an acrylic polymer having a functional group in a terminal or an acrylic polymer having a functional group in a side chain and a polyester having a functional group in a terminal are combined with these functional groups. A method of binding with a reactive bifunctional coupling agent. In the former method, a graft copolymer in which the polyester is a trunk polymer and the acrylic polymer is a branch polymer is obtained,
In the latter method, a graft copolymer in which the acrylic polymer is a trunk polymer and the polyester is a branch polymer is obtained. Examples of the functional groups of the polyester and the acrylic polymer include the functional groups described in (3) above.

In the above preparation methods (1) to (4),
When the polyester is the backbone polymer, 30 to 99.9 mol%, particularly 40 to 99.5 mol%, is used as the dicarboxylic acid component.
It is preferred to use mol% of aromatic dicarboxylic acid and 0 to 70 mol%, in particular 0 to 60 mol%, of aliphatic and / or cycloaliphatic dicarboxylic acids. Further, as in the preparation method of the above (2), a dicarboxylic acid having a polymerizable unsaturated double bond may be used as necessary. The dicarboxylic acid is preferably used in an amount of 0.5 to 10 mol%, particularly 2 to 7 mol%, of all carboxylic acid components.

The diol component comprises at least one of an aliphatic glycol having 2 to 10 carbon atoms, an alicyclic glycol having 6 to 12 carbon atoms, and a glycol having an ether bond. Also, if necessary, 0 to 5 mol%, preferably 0 to 3 mol%, of a trifunctional or higher polycarboxylic acid / polyol can be used.

In the above-mentioned preparation methods (3) and (4), when the acrylic polymer is a trunk polymer, the acrylic polymer is a functional group at the end of the polyester chain which is a branch polymer, for example, a hydroxyl group or a hydroxyl group. A homopolymer or copolymer containing at least a monomer unit having a functional group capable of reacting with a carboxyl group, whereby a functional group capable of reacting with a hydroxyl group or a carboxyl group is introduced into the backbone polymer chain, and these Is the grafting point of the backbone polymer.

Examples of the monomer having a functional group capable of reacting with the hydroxyl group at the terminal of the polyester chain include acrylic acid, methacrylic acid, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, acrylic chloride, methacrylic chloride, vinyl isocyanate and allyl isocyanate. , Methacryloyl isocyanate, vinyl trialkoxysilane, and the like.

Examples of the monomer having a functional group capable of reacting with the carboxyl group at the terminal of the polyester chain include a (meth) acrylic acid derivative having a hydroxyl group, for example, 2- (meth) acrylic acid derivative
Examples thereof include hydroxyethyl acrylate, 2-hydroxypropyl acrylate, those obtained by replacing these acrylates with methacrylate, vinyl isocyanate, allyl isocyanate, and methacryloyl isocyanate.

Other acrylic monomers include alkyl esters of acrylic acid and methacrylic acid, for example, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate and t-butyl acrylate.
Butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, phenylethyl acrylate, lauryl acrylate, stearyl acrylate,
And those obtained by replacing these acrylates with methacrylates; acrylic acid and methacrylic acid derivatives having an amide group, for example, acrylamide, N-methylacrylamide, N-methylolacrylamide, N.C. N-dimethylolacrylamide, N-methoxymethylacrylamide, N-phenylacrylamide, and those obtained by replacing these acrylamides with methacrylamide; acrylic acid and methacrylic acid derivatives having an amino group such as N, N-diethylaminoethyl acrylate and N, N-diethylaminoethyl methacrylate and the like can be mentioned. These monomers can be used alone or in combination of two or more. Further, other monomers other than those described above may be copolymerized if necessary.

Other monomers include nitriles such as acrylonitrile and methacrylonitrile; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether. Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone; vinyl chloride, vinylidene chloride; Vinyl halides such as vinyl bromide and vinyl fluoride; and aromatic vinyl compounds such as styrene, α-methylstyrene, t-butylstyrene, vinyltoluene, and vinylnaphthalene. These monomers can be used alone or in combination of two or more.

When the above-mentioned preparation methods (1) and (2) are adopted, when a reaction starting point can be generated in the polyester which is the trunk polymer, or when the polyester has a polymerizable unsaturated double bond in the molecule. When it has, a monomer containing at least the acrylic monomer is directly graft-polymerized to form a branched polymer. On the other hand, when the preparation method of the above (3) or (4) is employed, when the reaction starting point cannot be generated in the polyester which is the trunk polymer, or when the polyester does not have a polymerizable unsaturated double bond, An acrylic polymer having a functional group capable of reacting with a hydroxyl group or a carboxyl group at a polymer chain terminal is reacted with a hydroxyl group or a carboxyl group in a polyester molecule as a backbone polymer to form a branched polymer.

When making the graft copolymer soluble or dispersible in an organic solvent, when the acrylic polymer is a backbone polymer, the polyester is lipophilic and can be easily dispersed in an organic solvent. On the other hand, when the acrylic polymer is a branched polymer, an alkyl acrylate or alkyl methacrylate having an alicyclic or long-chain alkyl such as 2-ethylhexyl, cyclohexyl, lauryl, or stearyl should be used as a copolymer component of the acrylic polymer. Can be dispersed in an organic solvent.

When making the graft copolymer soluble or dispersible in an aqueous solvent, when the acrylic polymer is a backbone polymer, a hydrophilic polymer such as polyethylene glycol is introduced as a copolymer component into the polyester to make the polyester hydrophilic. On the other hand, when the acrylic polymer is a branch polymer, the polymerizable monomer having a hydrophilic group or a group capable of being changed to a hydrophilic group later is 5 to 95% by weight of the total monomer component, Preferably 10
90% by weight, more preferably 40 to 80% by weight, can be dispersed in an aqueous solvent by copolymerizing to form a branched polymer.

Examples of the polymerizable monomer having a hydrophilic group or having a group which can be converted into a hydrophilic group later include a monomer having a hydroxyl group, for example, 2
-Hydroxyethyl acrylate, 2-hydroxypropyl acrylate and those obtained by replacing these acrylates with methacrylates; monomers having a carboxyl group or a salt thereof, for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid , Alkyl maleic acid monoester, alkyl fumaric acid monoester, alkyl itaconic acid monoester, alkyl citraconic acid monoester, and salts thereof (sodium salt, potassium salt, ammonium salt and the like);
Monomers having a sulfonic acid group, for example, styrenesulfonic acid, vinylsulfonic acid, and salts thereof (sodium salt, potassium salt, ammonium salt, etc.); monomers which are acid anhydrides, for example, maleic anhydride, itaconic anhydride A monomer having a phosphate group or a salt thereof, for example, 2- (methacryloyloxy) ethylphosphonic acid and a salt thereof (sodium salt, potassium salt, ammonium salt, etc.); [2- (methacryloyloxy) ethyl]
Monomers having a quaternary ammonium group such as trimethylammonium chloride are exemplified.

For the graft polymerization, polymerization initiators of organic peroxides and organic azo compounds known to those skilled in the art can be used. Benzoyl peroxide, t-butyl peroxypivalate as an organic peroxide, 2,2′-azobisisobutyronitrile, 2,2 ′ as an organic azo compound
2′-azobis (2,4-dimethylvaleronitrile) and the like. The amount of the polymerization initiator used is at least 0.2% by weight or more, preferably 0.5% by weight or more based on the polymerizable monomer.

If necessary, a chain transfer agent for adjusting the chain length of the branch polymer, for example, octyl mercaptan, mercaptoethanol, 3-t-butyl-4-hydroxyanisole, etc. may be used. Is preferably added in the range of 0 to 5% by weight.

The above graft copolymer may form an anchor coat layer as it is. However, by further mixing and curing a crosslinking agent, an anchor coat layer having high water resistance can be formed. Examples of the crosslinking agent include a phenol formaldehyde resin which is a condensate of alkylated phenols, cresols, etc. with formaldehyde; an amino compound obtained by alkylating a aldehyde, melamine, benzoguanamine, etc. adduct of formaldehyde with alkyl ether having 1 to 6 carbon atoms. Resins; polyfunctional epoxy compounds; polyfunctional isocyanate compounds; blocked isocyanate compounds; polyfunctional aziridine compounds; oxazoline compounds.

As the method of forming the anchor coat layer, any of an in-line method of applying when producing a polyamide resin film and an off-line method of applying in a separate step from the production of the film can be used. In addition, a known coating method can be used for coating, and examples thereof include a roll coating method, a reverse coating method, a roll brushing method, a spray coating method, an air knife coating method, a gravure coating method, an impregnation method, and a curtain coating method. Can be used.

The anchor coat layer is formed by applying a graft copolymer-containing solution on a biaxially stretched polyamide-based film and drying it, or applying a graft copolymer-containing solution on an undrawn or uniaxially stretched polyamide-based film. After drying, uniaxial stretching or biaxial stretching may be further performed, if necessary, and then heat-fixed. When applying and drying the graft copolymer-containing solution on the biaxially stretched polyamide-based film, the drying temperature is preferably 150 ° C. or more, particularly preferably 200 ° C. or more, thereby improving the adhesion between the anchor coat layer and the polyamide-based film. I do.

The thickness of the anchor coat layer, preferably 0.
It is from 0.01 to 1 μm, more preferably from 0.02 to 0.5 μm. If the thickness is too small, the adhesion between the anchor coat layer and the polyamide-based film may not be sufficient. On the other hand, if the thickness is too large, blocking may occur, which is not preferable.

(Sealant Layer) In the gas barrier resin film of the present invention, it is preferable that a sealant layer is further laminated on the inorganic vapor-deposited layer. By heat-sealing the sealant layers, the gas barrier resin film can be made into a bag-like material, which becomes a film usable for packaging.

In order to satisfy the characteristics required for the gas barrier resin film of the present invention, that is, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes is 3.5% or less, it is used in the present invention. The sealant layer preferably has a specific compression modulus.

The materials used for the sealant layer include:
Although not particularly limited, for example, olefin-based resins such as polyethylene and ethylene-based copolymer, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polypropylene and propylene-based copolymer; polyvinyl chloride and vinyl chloride-based resin Vinyl chloride resins such as copolymers; vinylidene chloride resins such as vinylidene chloride-vinyl chloride copolymer; polyester resins such as polyethylene terephthalate; fluorine resins such as polytetrafluoroethylene; It is laminated on a vapor deposition layer, laminated by coating, or extrusion-laminated.

Among the above materials, the sealant layer is a polyolefin-based resin film in that the compression elastic modulus in hot water is particularly suitable and the heat sealability is good, and the following (a) It is preferable to satisfy (c).

(A) The compression modulus at 95 ° C. is preferably 8 kgf / mm ² or more, more preferably 15 kgf / mm ²
mm ² or more, particularly preferably 20 kgf / mm ² or more. When the compression modulus is less than 8 kgf / mm ² ,
The effect of shrinkage of the polyamide resin film layer after boiling cannot be suppressed from affecting the entire gas barrier resin film, and the shrinkage of the gas barrier resin film may increase. When the sealant film has a laminated structure, the compression elastic modulus is calculated by calculating the compression elastic modulus of each laminated layer (measured according to JIS-K7208) by the film thickness ratio of each layer (to the total thickness of the sealant film). Multiplied by.

(B) Vicat softening point is preferably 145 ° C.
Or less, more preferably 125 ° C. or less. The level of the Vicat softening point is an index of the heat resistance of the polyolefin resin. If the Vicat softening point is high, the heat resistance is excellent, and the compression modulus at the time of boiling is large. However, if the heat resistance is too high, the heat sealing property is deteriorated. Vicat softening point is 14
If the temperature exceeds 5 ° C., it is necessary to increase the heat sealing temperature or lengthen the pressing time, which is not desirable in the production process, and may cause poor heat sealing and adversely affect the contents of the package. The preferred lower limit of the Vicat softening point is 9.
When the temperature is lower than 0 ° C., the compression modulus is not in the above range, and the gas barrier property is adversely affected, the blocking resistance is poor, and the film tends to be inconvenient in winding in a production process. is there. When the sealant film has a laminated structure, the Vicat softening point is determined by the respective Vicat softening points (ASTM-D152) of the respective laminated layers.
5) and the film thickness ratio of each layer (to the total thickness of the sealant film).

(C) The maximum shrinkage of the polyamide film after boiled at 95 ° C. for 30 minutes
The maximum shrinkage of the gas barrier resin film after the boil treatment for 0 minutes is preferably less than 70%, more preferably 6%.
It is less than 0%, particularly preferably less than 50%. When this ratio is 70% or more, it indicates that the gas barrier resin film shrinks following the shrinkage of the polyamide film due to the boil treatment, and the gas barrier property is greatly reduced, which is contrary to the object of the present invention. In the present invention, the maximum shrinkage refers to the maximum shrinkage in the vertical and horizontal directions of the circular sample, and in directions forming angles of 30 °, 45 ° and 60 ° with these directions.

The polyolefin resin used in the present invention is not particularly limited as long as it satisfies the above-mentioned conditions. Specifically, polyethylene (linear low-density polyethylene, high-pressure low-density polyethylene, Homopolymers such as high-density polyethylene), polypropylene, polybutene-1, and poly-4-methylpentene-1; ethylene / propylene copolymer; ethylene / butene-1 copolymer; ethylene / 4-methyl-pentene-1 Copolymer, ethylene / decene-1 copolymer, propylene / 4-methyl-pentene-1 copolymer, propylene / butene-1 copolymer, decene / 4-methyl-pentene-1 copolymer, ethylene / Copolymers such as propylene / butene-1 copolymer and the like can be mentioned.

As the linear low-density polyethylene, ethylene and at least one kind of an α-olefin having 3 to 10 carbon atoms of preferably 0.2 to 20 mol%, more preferably 1 to 10 mol%, Those copolymerized in a liquid phase or a gas phase can be used, and specific examples of the α-olefin include propylene, butene-1, pentene-1, hexene-1, octene-1, nonene-1, decene-1, 4-methylpentene-1, 4-methylhexene-1, 4,4-dimethylpentene-1 and the like. Among linear low-density polyethylenes, the density is 0.900 to 0.960 g / cm ^2.
Is preferably used. A more preferred density is
0.910 to 0.950 g / cm ² .

The method for producing the polyolefin resin is not particularly limited, and may be any of a gas phase method and a liquid phase method. The catalyst may be a Ziegler-Natta catalyst, vanadium oxytrichloride, vanadium tetrachloride, organoaluminum, metallocene catalyst, or a mixture thereof. The preferred MI (melt index) range of the polyolefin resin is as follows:
1 to 15 g / 10 minutes (23 according to JIS K7210)
At 0 ° C). As the polyolefin-based resin, those deodorized by, for example, a reduced pressure treatment are preferably used.

The above-mentioned polyolefin-based resin may contain various additives which are usually added to the polyolefin composition as long as the heat-sealing property and the surface protection effect are not impaired.
For example, plasticizers, heat stabilizers, UV absorbers, antioxidants,
Colorants, fillers, antistatic agents, antibacterial agents, lubricants, antiblocking agents, and the like may be used in appropriate amounts. It is preferable to use spherical fine particles as the anti-blocking agent. The spherical fine particles have an effect of balancing the transparency, slipperiness and blocking resistance of the film.

It is preferable that the sealant film be excellent in slipperiness, blocking resistance, laminating property, gas barrier property, impact resistance, surface protection property, mechanical properties, etc. in addition to heat sealing property. Therefore, a single-layer structure may be used, but it is difficult to satisfy all of the above properties with a single layer. Therefore, it is preferable that each function be shared to form a stacked structure of two or more layers, more preferably three or more layers. .

In the case of a laminated structure, the polymer constituting each layer may be any of a copolymer, a modified product, a blend of different polymers, or a stacked different polymer. It is desired that the Vicat softening point of each layer is 90 ° C. or higher. If the temperature is lower than 90 ° C., it is difficult to obtain excellent gas barrier properties. In addition, since heat resistance is inferior, inconveniences such as fusion of portions other than the seal portion occur during the bag making and content filling steps. Of course, the Vicat softening point of each layer is preferably different.The layer with the lowest Vicat softening point is positioned as the outermost layer for heat sealing, and the layer with the highest Vicat softening point is used for mechanical properties such as compression modulus. It is good to position it for lamination on the inorganic vapor deposition layer side where heat resistance is required.

The Vicat softening point of the layer for lamination is preferably 90 ° C. or higher, more preferably 120 ° C. or higher. However, a combination of resins to be laminated should be selected so that the Vicat softening point of the entire sealant layer does not exceed 145 ° C.

When the sealant layer is laminated on the inorganic vapor-deposited layer in the form of a film, a co-extrusion molding method is preferable for producing a laminated sealant film as described above. For example, inflation molding using a circular die A method and a T-die molding using a T-die can be adopted. When performing T-die molding, it is preferable to set the draft rate to 1 to 10 and the resin temperature to 190 to 300 ° C.

When the sealant layer is formed by coating, a solution or an emulsion of a vinylidene chloride resin such as vinylidene chloride-vinyl chloride copolymer, a polyester resin such as polyethylene terephthalate, or a fluororesin such as polytetrafluoroethylene is used. Among them, a latex of vinylidene chloride resin and a solution in which vinylidene chloride resin is dissolved in a solvent such as tetrahydrofuran are preferred.

When a vinylidene chloride resin is applied, an isocyanate resin, a polyethyleneimine resin,
Adhesion promoters such as organic titanium type and polyurethane type,
A polyester adhesive can also be applied.

The thickness of the sealant layer is appropriately set according to the total thickness of the gas barrier resin film. The thickness of the sealant film is usually 5 to 150 μm, more usually 15 to 80 μm.

(Adhesive Layer) When such a sealant layer is laminated on the inorganic vapor-deposited layer, it is preferable that the sealant layer is provided via an adhesive layer in order to increase the adhesive strength of these layers. In order to satisfy the characteristics required for the gas barrier resin film of the present invention, that is, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes is 3.5% or less, the adhesive layer used in the present invention must be It is preferable to have a specific compression elastic modulus. Specifically, preferably the compression modulus at 40 ℃ 8.8kgf / mm ² or more, more preferably 17.6kgf / mm ² or more. By having such a compression elastic modulus, the heat shrinkage due to the boil treatment of the polyamide-based film is suppressed, and the heat shrinkage of the entire gas barrier resin film is reduced.

The material used for the adhesive layer is not particularly limited as long as it satisfies the above characteristics. Examples of the material include polyurethane resin, acrylic resin, polyester resin, epoxy resin, and the like. Various existing adhesives such as a vinyl chloride resin, a vinyl acetate resin, a polyethylene resin, a polypropylene resin, and a melamine resin are exemplified.

Further, one or more of the above-mentioned adhesive resins are added and melt-mixed to increase the adhesive strength, or a compound having, for example, a carboxyl group or an acid anhydride group as a functional group; ) A compound having an acrylic acid or (meth) acrylate ester skeleton; an epoxy compound having a glycidyl group or a glycidyl ether group; a compound having an oxazoline group, an isocyanate group, an amino group, a hydroxyl group, or the like can be used in combination.

The adhesive layer may be laminated by so-called dry lamination, wet lamination using an emulsion, melt extrusion lamination, co-extrusion lamination, or the like, or may be formed by coating. The coating amount of the adhesive layer is usually 0.1 to 10 g / solid content.
m ² , generally 1 to 5 g / m ² .

The gas barrier resin film of the present invention has a thickness of 10 to 100 from the viewpoint of strength, flexibility, economy and the like.
It can be selected according to the application within a range of 0 μm, particularly 30 to 300 μm. Further, the gas barrier resin film of the present invention can be laminated with paper, aluminum foil, wood, cloth, nonwoven fabric, or the like, a printed layer can be formed, or a printed film can be laminated as necessary.

The gas barrier resin film of the present invention comprises 9
3.5% maximum shrinkage after boiling at 5 ° C for 30 minutes
Or less, preferably 1.5% or less, more preferably 0.7% or less.
%, More preferably 0.4% or less. Preferably, the maximum shrinkage of the gas-barrier resin film after boiled at 95 ° C. for 30 minutes is preferably 70% with respect to the maximum shrinkage of the polyamide-based film after boiled at 95 ° C. for 30 minutes. , More preferably less than 60%, particularly preferably less than 50%. By having such characteristics, the gas barrier property is maintained even after the boil treatment and the retort treatment. Specifically, the amount of oxygen permeation after boil treatment at 95 ° C. for 30 minutes is preferably 15 cc / m ² · atm · day or less,
More preferably, it is 10 cc / m ² · atm · day or less, and the water vapor transmission rate after boiling at 95 ° C. for 30 minutes is preferably 10 g / m ² · day or less, more preferably 6 g / m ² · day or less. It has the following performance.

When the maximum shrinkage ratio after boil treatment at 95 ° C. for 30 minutes exceeds 3.5%, shrinkage due to boil treatment and retort treatment causes cracks and peeling of the inorganic vapor-deposited layer, resulting in poor gas barrier properties. descend.

The gas barrier resin film having the above-mentioned properties can be obtained by combining one or more of the following properties. The shrinkage stress of the polyamide film is in a suitable range (specifically, the maximum shrinkage stress at 170 ° C. is preferably 9
00 gf / mm ² or less, more preferably 400 gf / m 2
m ² or less, particularly preferably 200 gf / mm ² or less). The shrinkage rate of the polyamide film is in a suitable range (specifically, the maximum shrinkage rate after heat treatment at 170 ° C. for 10 minutes is preferably 3.5% or less, more preferably 1.5%.
Or less, particularly preferably 0.7% or less). The adhesive strength between the polyamide-based film and the inorganic vapor-deposited layer is within a suitable range (specifically, the adhesive strength measured in air after boiled at 95 ° C. for 30 minutes is preferably 1).
00 g / 15 mm or more, more preferably 150 g / 15
mm or more, in particular, adhesion strength measured in water after boiled at 95 ° C. for 30 minutes is preferably 50 g / 15 mm
Or more, more preferably 90 g / 15 mm or more). The compressive elastic modulus of the anchor coat layer is in a suitable range (specifically, the compressive elastic modulus at 40 ° C. of the anchor coat layer is preferably 3.0 kgf / mm ² or more, more preferably 5.0 kgf / mm ^2. Above, particularly preferably 9.8
kgf / mm ² or more). The compression elastic modulus of the sealant layer is within a suitable range (specifically, the sealant layer is a polyolefin resin film, and the compression elastic modulus at 95 ° C. is preferably 8 kgf).
/ Mm ² or more, more preferably 15 kgf / mm ² or more, and still more preferably 20 kgf / mm ² or more). The compressive modulus of the adhesive layer is in a suitable range (specifically, the compressive modulus of the adhesive layer at 40 ° C. is preferably 8.8).
kgf / mm ² or more, more preferably 17.6 kgf / mm ²
mm ² or more).

In the present invention, by reducing the shrinkage rate and shrinkage stress of the polyamide film, the gas barrier property of the gas barrier resin film after the boil treatment is improved, but the compression elastic modulus of the sealant layer is increased. Thereby, even if the contraction rate and the contraction stress of the polyamide film are high to some extent, the gas barrier property of the gas barrier resin film after the boil treatment is improved. Further, the gas barrier property of the gas barrier resin film after the boil treatment is improved by increasing the compression elastic modulus of the anchor coat layer and the adhesive layer. As described above, the gas barrier property is improved as a result of the combination of the contractility and the elasticity of each layer.

In the gas barrier resin film of the present invention, the films are heat-sealed at ² kgf / cm ² for 1 second, and then subjected to a 90 ° peel test to determine the temperature at which the peel strength becomes 500 g / 15 mm or more. The heat sealing start temperature when the heat sealing start temperature is set is preferably 160 ° C. or lower, more preferably 135 ° C. or lower, and particularly preferably 120 ° C. or lower.

Further, the gas barrier resin film of the present invention has a blocking resistance, measured according to ASTM-D1893-67, of preferably 10 g / 20 mm or less, more preferably 7 g / 20 mm or less. It is.

The gas barrier resin film of the present invention maintains its excellent gas barrier properties even after boil treatment and retort treatment. Therefore, as a packaging material for food or the like to which these treatments are applied in the packaging process, For example, miso, pickles,
Side dishes, baby food, tsukudani, konjac, chikuwa, kamaboko, processed fishery products, meatballs, hamburgers, genghis khan, ham, sausage, other processed meat products, tea, coffee, tea, bonito, toro kelp, potato chips, butter peanuts Such as oil confections, rice confectionery, biscuits, cookies, cakes, buns, castella, cheese, butter, cut rice cake, soups, sauces, ramen, wasabi, toothpaste, pet food, pesticides, fertilizers, infusion packs It is also used for packaging of industrial materials such as medical, electronic, chemical, and mechanical products such as semiconductors and precision materials. Also,
Usage forms of the packaging material include bags, lid materials, cups, tubes, standing bags, and the like.

[0090]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples unless it exceeds the gist. <Measurement method> Gas barrier property The amount of oxygen permeation is measured using an oxygen permeability measuring device (OX-TRAN 1).
0 / 50A: Made by Modern Controls)
%, The temperature was 25 ° C., and oxygen substitution was performed after 2 days. The amount of water vapor permeation can be measured using a water vapor permeability measuring device (PERMATRA).
N: manufactured by Modern Controls) after measuring the temperature after replacing the water vapor with steam at a temperature of 40 ° C. and a humidity of 90% for 2 days. 2. Shrinkage Ratio of Gas Barrier Resin Film The gas barrier resin film is cut into a circular shape having a diameter of 200 mm.
The dimensions in the directions forming angles of ° and 60 ° were measured at a temperature of 25 ° C and a humidity of 0%. Then, it boiled at 95 degreeC for 30 minutes, measured the dimension of each direction at room temperature (about 25 degreeC), and calculated the shrinkage rate. The maximum value among them was defined as the maximum contraction rate. 3. Shrinkage rate of polyamide-based film A polyamide-based film is cut into a circle having a diameter of 200 mm. It was measured in%. Thereafter, after a heat treatment at 170 ° C. for 10 minutes, or after a boil treatment at 95 ° C. for 30 minutes, room temperature (about 2 ° C.).
(5 ° C.), and the shrinkage was calculated by measuring the dimensions in each direction. The maximum value among them was defined as the maximum contraction rate. 4. Shrinkage stress of polyamide-based film The longitudinal direction and the transverse direction of the polyamide-based film, and the directions forming angles of 30 °, 45 °, and 60 ° with these directions,
It was calculated from the load-deformation curve, and the maximum value was defined as the maximum shrinkage stress. 5. Compressive modulus of sealant layer, arcer coat layer and adhesive layer For each layer, JIS in air at 40 ° C or 95 ° C
It was measured with an R-GS T-SS TMA measuring device according to -K7208. However, with respect to the anchor coat layer and the adhesive layer, coating was performed on a release film, dried, and then peeled off. 6. Adhesive strength After boil-treating the gas barrier resin film at 95 ° C. for 30 minutes, the film is in air (about 25 mm) according to JIS-K6854.
C) or in water (about 25 ° C.), the s-s curve between the polyamide film and the inorganic vapor-deposited layer when the polyamide film and the inorganic vapor-deposited layer are peeled off by 90 °, manufactured by Toyo Sokki Co., Ltd.
It was measured by Tensilon UTM2. In addition, the peel strength in water, or simply, water is dropped on the peel interface, and s-s
Equivalent evaluations can be obtained by measuring the curves. An electron microscope and a fluorescent X-ray apparatus manufactured by Rigaku Kogyo Co., Ltd. were used for identification of the peeling interface. 7. Vicat softening point of sealant film For sealant film, AS at room temperature (about 25 ° C)
It measured based on TM-D1525. 8. Heat sealing start temperature 2 kg of gas barrier resin films at various temperatures
After heat sealing at f / cm ² for 1 second, a 90 ° peel test was performed, and the temperature at which the peel strength became 500 g / 15 mm or more was defined as the heat sealing start temperature. 9. Blocking resistance Gas barrier resin film at room temperature (about 25 ° C)
Was measured in accordance with ASTM-D1893-67.

Example 1 As a polyamide film, a nylon film (6-nylon, thickness 15 μm, maximum shrinkage stress at 170 ° C .: 9)
Using 100 gf / mm ² at 170 ° C. for 10 minutes and a maximum shrinkage of 3.5% after heat treatment, an inorganic vapor-deposited layer was formed in the following procedure.

The 6-nylon film was sent to a vacuum evaporation apparatus, and the inside of the chamber was maintained at a pressure of 1 × 10 ⁻⁵ Torr, and SiO ₂ : 62% by weight and Al ₂ O ₃ : 38% by weight.
The mixed oxide was evaporated by electron beam heating at 15 kw, and a colorless and transparent inorganic oxide layer having a thickness of 270 ° was deposited on a nylon film to form an inorganic deposited layer. Next, unstretched polyethylene (thickness: 55 μm) as a sealant layer was dry-laminated on the inorganic vapor-deposited layer using an adhesive (“A310 / A10” manufactured by Takeda Pharmaceutical Co., Ltd., coating amount 2 g / m ² ). At 45 ° C. for 4 days to obtain a gas barrier resin film. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

Example 2 In Example 1, 17% of polyamide film was used.
Maximum shrinkage stress at 0 ° C. is 600 gf / mm ² , 170 ° C.
The maximum shrinkage after heat treatment for 10 minutes is 3.5% 6-
A gas barrier resin film was obtained in the same manner as in Example 1, except that a nylon film was used and silicon monoxide (SiO) was used as a material of the inorganic vapor deposition layer. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

Example 3 In Example 1, 17% of polyamide film was used.
Maximum shrinkage stress at 0 ° C. is 400 gf / mm ² , 170 ° C.
The maximum shrinkage after heat treatment for 10 minutes is 1.5% 6-
A gas barrier resin film was obtained in the same manner as in Example 1 except that a nylon film was used. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

Example 4 In Example 1, 17% of polyamide film was used.
Maximum shrinkage stress at 0 ° C is 200 gf / mm ² , 170 ° C
The maximum shrinkage after heat treatment for 10 minutes is 0.7% 6-
A gas barrier resin film was obtained in the same manner as in Example 1 except that a nylon film was used. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

Example 5 In Example 4, a polyester resin having a thickness of 0.5 μm (byron, manufactured by Toyobo Co., Ltd .; obtained anchor coat layer) was used as an anchor coat layer between the 6-nylon film and the inorganic vapor-deposited layer. Compression modulus at 40 ° C. of 12 kg
f / mm ² ), except that a gas barrier resin film was obtained in the same manner as in Example 4. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

Comparative Example 1 In Example 1, 17% of polyamide-based film was used.
Maximum shrinkage stress at 0 ° C. is 1200 gf / mm ² , 170
The maximum shrinkage after heat treatment at 10 ° C for 10 minutes is 4.2% 6
-A gas barrier resin film was obtained in the same manner as in Example 1 except that a nylon film was used. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and in water), the amount of oxygen permeation and the amount of water vapor permeation were measured. Table 1 shows the results.

[0098]

[Table 1]

From Table 1, it can be seen that the gas barrier resin films obtained in Examples 1 to 5 maintain very low oxygen and water vapor transmission rates even after boiled at 95 ° C. for 30 minutes. On the other hand, in the gas barrier resin film obtained in Comparative Example 1, the amount of oxygen permeation and the amount of water vapor permeation after the boil treatment at 95 ° C. for 30 minutes are significantly increased, and it can be seen that the gas barrier properties are significantly reduced.

Example 6 As a polyamide-based film, a film was formed using 6-nylon containing ε-caprolactam as a main raw material. During the film forming process, the surface was subjected to corona treatment. The maximum shrinkage (B%) of this film after boiled at 95 ° C. for 30 minutes is 1.5% (1.5% in the horizontal direction, 1.0% in the vertical direction).
%), And the shrinkage stress per unit sectional area is 1.2
kgf / mm ² .

The obtained 6-nylon film subjected to corona treatment was set on an unwinding roll of a vapor deposition apparatus. Next, while heating and evaporating silicon dioxide and aluminum oxide as evaporation materials using an electron beam heating type vacuum evaporation apparatus, a 6-nylon film was run on the evaporation source to form an inorganic evaporation layer. The thickness of the inorganic vapor deposition layer is 200
Å, the content of aluminum oxide was 40% by weight.

A two-component polyurethane adhesive (“A310 / A10” manufactured by Takeda Pharmaceutical Co., Ltd., Tg :−)
12 ° C.) at 5 g / m ² , and a polyolefin resin film (3) shown in Table 2 as a sealant layer thereon.
Was dried and laminated to obtain a gas barrier film.

Examples 7 to 10 A gas barrier resin film was obtained in the same manner as in Example 6, except that a polyolefin resin film having the structure shown in Table 2 was used as the sealant layer.

Example 11 In Example 10, a 0.5 μm thick anchor coat layer was formed between the 6-nylon film and the inorganic vapor-deposited layer.
Polyester resin (byron, manufactured by Toyobo Co., Ltd .; compression modulus at 40 ° C. of the obtained anchor coat layer: 12 k)
gf / mm ² ), except that a gas barrier resin film was obtained in the same manner as in Example 10.

Example 12 In Example 11, a polyester resin "Byron" (Toyobo Co., Ltd.) was used as a two-component polyurethane adhesive.
Co., Ltd.) and isocyanate curing agent "Coronate L" (manufactured by Nippon Polyurethane Co., Ltd.)
Compression modulus at 0 ° C .: 10 kgf / mm ² , thickness 5
μm), to obtain a gas barrier resin film in the same manner as in Example 11.

Table 3 shows the compression elastic modulus at 95 ° C. and the Vicat softening point of the polyolefin resin films used in Examples 6 to 12. In addition, the maximum shrinkage (A) of the gas barrier resin film after the boil treatment at 95 ° C. for 30 minutes.
%), The maximum shrinkage (A / B) of the gas barrier resin film with respect to the maximum shrinkage of the polyamide film after boiled at 95 ° C. for 30 minutes, sealing start temperature, blocking resistance, oxygen permeation amount, water vapor permeation The amount and the adhesion strength between the polyamide film and the inorganic vapor-deposited layer (in air and in water) were measured. Table 4 shows the results.

[0107]

[Table 2]

[0108]

[Table 3]

[0109]

[Table 4]

The materials and abbreviations of each layer described in Table 2 are as follows.

(1) Polyamide-based film Polycaproamide: 6-nylon (2) Inorganic vapor-deposited layer Silicon dioxide + aluminum oxide: SiO ₂ + Al ₂ O ₃ (3) Polyolefin-based film High-density polyethylene: HDPE High-pressure low-density polyethylene : LDPE Linear low density polyethylene: L-LDPE Ethylene-propylene random copolymer: Et-Pr
(R) Ethylene-propylene block copolymer: Et-Pr
(B) Ethylene-propylene-butene ternary random copolymer: Et-Pr-Bu biaxially oriented polypropylene: OPP

Example 13 Nylon film (6-na) was used as a polyamide film.
IRON 15 microns Maximum shrinkage stress 470 at 170 ° C
gf / mm^Two) To prepare an inorganic vapor-deposited layer by the following procedure
did. 6-nylon film is supplied to a vacuum evaporation apparatus,
1 × 10 inside the chamber^-FiveTorr pressure
Lass (SiO_Two 80 wt%, Al_TwoO _Three 20wt
%) Was evaporated by heating with a 15 kW electron beam to a thickness of 20%.
A colorless and transparent inorganic vapor deposition layer of 0 ° was deposited. Sealant
Unstretched polyethylene (L6100 manufactured by Toyobo Co., Ltd.)
 55 micron) with adhesive (A310 / A manufactured by Takeda Pharmaceutical Co., Ltd.)
10 application amount 2g / m^Two) Dry lamination at 45 ℃
Aging for 4 days to remove the gas barrier resin film
Obtained. About this gas barrier resin film, 95
C, maximum shrinkage after boiled for 30 minutes, 6-Niro
Adhesion strength between inorganic film and inorganic vapor deposition layer (in air and water
Medium), the amount of oxygen permeation and the amount of water vapor permeation were measured. as a result
Are shown in Table 5.

Example 14 In Example 13, a 0.5 μm-thick arc coat layer was formed between the 6-nylon film and the inorganic vapor-deposited layer.
Polyester resin (byron, manufactured by Toyobo Co., Ltd .; compression modulus at 40 ° C. of the obtained anchor coat layer: 12 k)
gf / mm ² ), except that a gas barrier resin film was obtained in the same manner as in Example 13. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and water), the amount of oxygen permeation,
The water vapor transmission rate was measured. Table 5 shows the results.

Example 15 In Example 13, glass (SiO ₂₎ was used as an evaporation material.
A gas barrier resin film was obtained in the same manner as in Example 13, except that an inorganic vapor-deposited layer was laminated using silicon monoxide (SiO 2 purity 99%) instead of 80 wt% and Al ₂ O ₃ 20 wt%. . For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and water), the amount of oxygen permeation, and the amount of water vapor permeation were measured. Table 5 shows the results.

Comparative Example 2 In Example 13, a nylon film (6 nylon,
Maximum shrinkage stress at 15 microns, 170 ° C .: 980 gf
/ Mm ² ), except that a gas barrier resin film was obtained in the same manner as in Example 13. For this gas barrier resin film, the maximum shrinkage after boil treatment at 95 ° C. for 30 minutes, the adhesion strength between the 6-nylon film and the inorganic vapor-deposited layer (in air and water), the amount of oxygen permeation, and the amount of water vapor permeation were measured. Table 5 shows the results.

Comparative Example 3 A gas barrier resin film was obtained in the same manner as in Example 14, except that polyvinyl alcohol (thickness: 2 μm) was used as the anchor coat layer. About this gas barrier resin film, 95 ° C,
Maximum shrinkage after 30 minutes boil treatment, adhesion strength between 6-nylon film and inorganic vapor deposited layer (in air and water),
The oxygen permeation amount and the water vapor permeation amount were measured. Table 5 shows the results.
Shown in

[0117]

[Table 5]

From Table 5, it can be seen that the gas barrier resin films obtained in Examples 13 to 15 maintain very low oxygen and water vapor transmission rates even after boiled at 95 ° C. for 30 minutes. On the other hand, in the gas barrier resin films obtained in Comparative Examples 2 and 3, the amount of oxygen permeation and the amount of water vapor permeation after boil treatment at 95 ° C. for 30 minutes are remarkably increased, and the gas barrier properties are significantly reduced. .

[0119]

As apparent from the above description, according to the present invention, it is possible to provide a gas barrier film which does not impair its excellent gas barrier properties and moisture resistance even after boil treatment or retort treatment. . Therefore, including packaging materials for food, medicine, and industrial materials,
It can be used for a wide range of packaging materials requiring a high degree of gas barrier properties, and its industrial use value is great.

Continued on the front page (72) Inventor Yozo Yamada 2-1-1 Katata, Otsu-shi, Shiga Prefecture Toyo Spinning Co., Ltd. (72) Inventor Chikao Morishige 2-1-1 Katata, Otsu-shi, Shiga Toyo (72) Inventor Hideyuki Mitamura 344 Maehata, Inatsuyama-shi, Aichi Prefecture, Japan In-house plant at Toyo Spinning Co., Ltd. (72) Inventor Satoshi Nori 10-24 Toyocho, Tsuruga-shi, Fukui Tsuruga Film Inside the Tsuruga Plant Co., Ltd. (72) Inventor Shinji Fujita 2-1-1 Katata, Otsu City, Shiga Prefecture Toyo Boseki Co., Ltd. (56) References JP-A 1-267036 (JP, A) JP-A 7 JP-A-290565 (JP, A) JP-A-7-256750 (JP, A) JP-A-4-128027 (JP, A) JP-A-10-7904 (JP, A) JP-A-10-6429 (JP, A) ) JP-A-10-16120 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (16)

(57) [Claims] 1. A is a polyamide film and no machine deposited layer a gas barrier resin film that is at least stacked, 95 ° C. of the gas barrier resin film, the maximum shrinkage rate after boiling for 30 minutes 3.5 der below% is, and 9
After boiling treatment at 5 ° C. for 30 minutes, the inorganic vapor-deposited layer
Adhesion strength measured in water with amide-based film is 50g
/ Gas barrier resin film characterized in der Rukoto than 15 mm. 2. The gas barrier resin film according to claim 1, wherein the polyamide film has a maximum shrinkage stress at 170 ° C. of 900 gf / mm ² or less. 3. A polyamide film having a temperature of 170.degree.
The gas barrier resin film according to claim 1, wherein the maximum shrinkage after heat treatment for 3.5 minutes is 3.5% or less. 4. The method according to claim 1, wherein the unstretched polyamide-based film is made of (Tg + 10) ° C. or more (Tc + 2
0) After stretching in the longitudinal direction by 2.5 to 4.0 times at a temperature of not more than 0 ° C, pre-transverse stretching is performed by 1.1 to 2.9 times at a temperature of (Tc + 20) ° C or more and (Tc + 70) ° C or less. Then, at a temperature of (Tc + 70) ° C or higher and (Tm-30) ° C or lower,
After the subsequent-stage transverse stretching was performed so that the overall transverse stretching ratio was about 3.0 to 4.5 times, (Tm-30) ° C using a tenter.
0 to 10% in the horizontal direction at a temperature not lower than (Tm-10) ° C
The gas barrier resin film according to claim 3, which is a film subjected to relaxation heat treatment. 5. The adhesive strength between the inorganic vapor-deposited layer and the polyamide film measured in air after boil treatment at 95 ° C. for 30 minutes is 100 g / 15 mm or more. Gas barrier resin film. 6. The gas barrier resin film according to claim 1, characterized by further anchor coat layer between the polyamide Phil beam and the inorganic vapor deposition layer is formed. 7. The gas barrier resin film according to claim 6 , wherein the compression modulus of the anchor coat layer at 40 ° C. is 3.0 kgf / mm ² or more. 8. anchor coat layer, characterized in that it is a layer containing a graft copolymer of a polyester resin or a polyester and an acrylic polymer, wherein
Item 7. A gas barrier resin film according to Item 6 . 9. The gas barrier resin film according to claim 1, wherein a sealant layer is further laminated on the inorganic vapor-deposited layer. 10. The gas barrier resin film according to claim 9 , wherein the sealant layer is a polyolefin resin film and satisfies the following conditions (a) to (c). (a) The compression modulus at 95 ° C. is 8 kgf / mm ² or more. (b) Vicat softening point is 145 ° C or less. (c) The maximum shrinkage ratio of the gas barrier resin film after boil treatment at 95 ° C. for 30 minutes is 7 relative to the maximum shrinkage ratio of the polyamide film after boil treatment at 95 ° C. for 30 minutes.
It is less than 0%. 11. The method of claim wherein the further adhesive layer between the inorganic deposited layer and the sealant layer is formed 9
3. The gas barrier resin film according to item 1. 12. adhesive layer at 40 ° C. compressive modulus is equal to or is 8.8 kgf / mm ² or more claims
Item 12. The gas barrier resin film according to Item 11 . 13. The gas barrier resin film according to claim 1, wherein an oxygen permeation amount after boil treatment at 95 ° C. for 30 minutes is 15 cc / m ² · atm · day or less. 14. The gas barrier resin film according to claim 1, wherein a water vapor transmission rate after boil treatment at 95 ° C. for 30 minutes is 10 g / m ² · day or less. 15. The films are put together at 2 kgf / cm.
^2. The gas barrier resin film according to claim 1, wherein a temperature at which the peel strength becomes 500 g / 15 mm or more is 160 ° C. or less after a 90 ° peel test is performed after heat-sealing with ² for 1 second. 16. The gas barrier resin film according to claim 1, wherein the blocking resistance measured according to ASTM-D1893-67 is 10 g / 20 mm or less.