JP2000006341A - Gas barrier laminated film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the excellent transparency and gas barrier properties of a film from being impaired through a boiling treatment by a method wherein a gas barrier layer made of a thin film metal oxide layer is formed on a polyamide film and then a polyolefin film is laminated on the gas barrier layer so as to realize a specified elongation percentage in hot water under specified conditions and a specified shrinkage factor after being left in air. SOLUTION: A gas barrier laminated film is prepared by forming a gas barrier layer made of a thin film metal oxide layer on a polyamide film so as to satisfy the following conditions: the elongation percentage of the film immersed in a hot water kept at 95 deg.C for 30 min is set to be 1% or less, and the shrinkage factor of the film immersed in a hot water kept at 95 deg.C and then left in an air for 15 min is set to be 3% or less. Further, the polyamide film consists of a resin composition of the mixture and/or the copolymer of a component such as a terephthalic acid or the like and an aliphatic polyamide- based resin, the aliphatic polyamide-based resin and a flexing fatigue resistance improver.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a gas barrier property and a moisture-proof property which are important properties for packaging films for fresh foods, processed foods, pharmaceuticals, medical equipment, electronic parts, etc., as well as transparency and handleability. The present invention relates to a laminated film or sheet excellent in the above.

[0002]

2. Description of the Related Art In recent years, food packaging forms have changed drastically due to changes in food distribution and dietary habits, and the required characteristics of packaging films and sheets (hereinafter represented by films) have become increasingly severe. Is coming. Deterioration of product 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 but also in terms of food hygiene. As a method of preventing such quality deterioration, antioxidants and preservatives have been directly added to foods in the past.
In recent years, regulations on food additives have become stricter from the standpoint of consumer protection, and it has been required to reduce the amount of food additives or to eliminate them. There is an increasing demand for a packaging film that does not cause deterioration in the quality of food as a result of processing, boiling treatment, retort treatment, and the like. That is, in the packaging of fish meat, animal meat, shellfish, etc., it is important to suppress the oxidation and deterioration of proteins and oils and fats, and to maintain taste and freshness. It is desired to block the transmission of light. Moreover, when wrapped in a gas barrier film, the fragrance of the contents is retained and the permeation of moisture is prevented, so that the moisture absorption of dried products is suppressed,
In the case of a water-containing substance, deterioration and solidification due to evaporation of water are suppressed, and a fresh flavor at the time of packaging can be maintained for a long time. For these reasons, paste products such as kamaboko, butter, dairy products such as cheese, miso, tea, coffee, ham and sausage, instant food, castella, biscuits and other confectionery packaging films have the gas barrier properties and moisture barrier properties. Is a very important characteristic. These properties are not limited to food packaging films, but are also extremely important as medical products that need to be handled under aseptic conditions or packaging films for electronic components that require rust prevention. As a film having excellent gas barrier properties, a film obtained by laminating a metal foil such as aluminum on a plastic film, or a film coated with vinylidene chloride or an ethylene vinyl alcohol copolymer is known. Further, as a device using an inorganic thin film, a device in which a deposited film of silicon oxide, aluminum oxide, or the like is laminated is also known. Conventional gas barrier films as described above include:
The following problems have been pointed out respectively. Aluminum foil laminated as a gas barrier layer is excellent in economics and gas barrier properties, but is opaque, so the contents cannot be seen when packaged, and it does not transmit microwaves, so it can not be processed with a microwave oven . Further, those coated with vinylidene chloride or ethylene vinyl alcohol copolymer do not have sufficient gas barrier properties against water vapor, oxygen and the like, and the performance is particularly deteriorated by high temperature treatment. In addition, there is a concern that vinylidene chloride may cause air pollution due to generation of chlorine gas at the time of incineration. Therefore, a resin film having an inorganic vapor-deposited layer such as silicon oxide or aluminum oxide formed thereon as a gas barrier layer has been proposed. As a substrate film on which silicon oxide, aluminum oxide, or the like is deposited, a polyester film (PET) has been conventionally used. For example, PET / deposited layer / adhesive layer / stretched nylon (ONY) / adhesive layer / not In the case of a laminated structure such as drawn polypropylene (CPP), a problem arises in that the gas barrier properties after boiling or retorting are deteriorated due to shrinkage of nylon. Therefore, recently, it is customary to adopt a laminated structure such as PET / deposited layer / adhesive layer / PET / adhesive layer / unstretched polypropylene (CPP). Insufficient strength is a problem. As described above, it is pointed out that a gas barrier film having a laminated structure provided with an inorganic vapor-deposited layer such as silicon oxide or aluminum oxide does not always have sufficient strength, and that the gas barrier property deteriorates due to boiling treatment or retort treatment. Therefore, as a measure for improving strength, a laminated film using stretched nylon as a vapor deposition base material whose shrinkage rate has been reduced in advance by heat treatment (Japanese Patent Publication No. 7-126)
49) has been proposed. However, the manufacturing process and the transportation and storage processes become complicated, which is not practical. In addition, nylon with a small shrinkage rate during high-temperature treatment (Japanese
In No. 12649, the sum of the absolute values of the dimensional change rates in the vertical and horizontal directions when heated at 120 ° C. for 5 minutes is 2% or less.
However, boiling treatment, which is a high-temperature hot water treatment, cannot maintain excellent gas barrier properties. Nylon-laminated film with reduced shrinkage during high-temperature hot water treatment (Japanese Unexamined Patent Publication No. 7-2
76571) has also been proposed. However, since the number of films to be laminated increases, the manufacturing process and the process of transport and storage become complicated, resulting in poor economic efficiency, and the thicker film makes handling difficult, which is not practical.
In addition, Japanese Patent Publication No. 51-48511 discloses a gas barrier film that is transparent, allows the contents to be seen through, and is applicable to a microwave oven.
A gas barrier film on which an xOy system (for example, SiO ₂ ) is deposited has been proposed. However, a SiOx-based (x = 1.3 to 1.8) vapor-deposited film having good gas barrier properties has a slightly brown color, and cannot be said to be sufficient in quality as a transparent gas barrier film. JP-A-62-101
No. 428 describes a device provided with an inorganic vapor-deposited layer mainly composed of aluminum oxide, which has insufficient gas barrier properties. The Al ₂ O ₃ .SiO ₂ -based gas barrier layer is also excellent in boiling resistance and retort resistance. However, Al ₂ O ₃ and SiO ₂
Are stacked, and the formation of the gas barrier layer is complicated and requires a large-scale apparatus. In addition, films using these inorganic thin films as gas barrier layers are still inadequate from the viewpoint of achieving both gas barrier properties and flex resistance. That is, in order to provide excellent boiling resistance and retort resistance, a certain degree or more (for example, 2,000
(About 0 ° or more) is required. On the other hand, when the film thickness is increased, there is a problem that the bending resistance is deteriorated and it cannot withstand a drop impact, and has a sufficient gas barrier property and moisture proof property.
Further, a gas barrier film which is excellent in boiling resistance and retort resistance, has excellent bending resistance, and can sufficiently withstand a drop impact has not been proposed at present.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has as its object the purpose of having excellent transparency and gas barrier properties, and even after boiling and printing processes. To economically provide a gas-barrier laminated film or sheet having strength characteristics that do not impair barrier properties, have good bending resistance, sufficiently withstand drop impact, and also have excellent heat sealing properties. is there.

[0004]

The gas barrier laminate film of the present invention is a film in which a gas barrier layer composed of a metal oxide thin film layer is formed on a polyamide film, and a polyolefin film is laminated on the metal oxide thin film layer. A gas barrier laminated film satisfying the following conditions. (1) It is immersed in hot water of 95 ° C. and has an elongation of 1% or less after 30 minutes. (2) The shrinkage after immersion in hot water of 95 ° C. for 15 minutes in air is 3% or less. The polyamide film contains 30 to 100 parts by weight of the following X,
Of Z and 70 to 0 parts by weight and Z of 0 to 10 parts by weight. (X): a mixture and / or copolymer of an aromatic polyamide resin component (a) composed of terephthalic acid or isophthalic acid and an aliphatic diamine and an aliphatic polyamide resin (b), wherein the aromatic polyamide resin component ( (Y): aliphatic polyamide-based resin (Z): flex fatigue resistance improving agent

Preferably, an anchor coat layer containing polyester as a main component is laminated between the polyamide film and the inorganic metal thin film layer, and the metal oxide thin film layer is a mixture thin film layer of silicon oxide and aluminum oxide. It is more preferable that the content of aluminum oxide in the mixture of silicon oxide and aluminum oxide is 5% by weight or more and 45% by weight or less.

The gas-barrier laminated film of the present invention having the above-mentioned structure is a gas-barrier laminated film having excellent gas barrier properties even at the initial stage and after the boil treatment, and having excellent transparency and pinhole resistance. .

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, each layer constituting material specified in the present invention will be described in detail. The gas barrier laminated film of the present invention is a film in which a gas barrier layer composed of a metal oxide thin film layer is formed on a polyamide film, and a polyolefin film is laminated on the metal oxide thin film layer,
It is a gas barrier laminated film satisfying the following conditions. (1) It is immersed in hot water of 95 ° C. and has an elongation of 1% or less after 30 minutes. (2) The shrinkage after immersion in hot water of 95 ° C. for 15 minutes in air is 3% or less. The polyamide film contains 30 to 100 parts by weight of the following X,
Is preferably prepared using a polyamide resin composition obtained by mixing 70 to 0 parts by weight of Z and 0 to 10 parts by weight of Z. (X): a mixture and / or copolymer of an aromatic polyamide resin component (a) composed of terephthalic acid or isophthalic acid and an aliphatic diamine and an aliphatic polyamide resin (b), wherein the aromatic polyamide resin component ( (Y): aliphatic polyamide-based resin (Z): flex fatigue resistance improving agent

The aliphatic polyamide used in the present invention includes nylon 4, nylon 6, nylon 7, nylon 11, nylon 12, nylon 66, nylon 612, nylon 46, and copolymers and blends thereof. However, nylon 6 and nylon 66 are preferred.

The polyamide laminated film of the present invention can be produced by a known production method. That is, a method in which a polymer is melted using an extruder and then produced by extrusion can be employed. Furthermore, the polyamide-based laminated film of the present invention can be used as either an unstretched film or a stretched film, but is preferably stretched in a uniaxial or biaxial direction in order to improve the processability of the film. . As the stretching method, a known method such as a tenter-type sequential biaxial stretching method, a tenter-type simultaneous biaxial stretching method, and a tubular method can be used. Also,
Various additives, for example, an antioxidant, a weathering agent, an anti-gelling agent, an anti-blocking agent, a pigment, an antistatic agent and the like may be appropriately blended as long as the purpose and performance of the laminated polyamide film of the present invention are not impaired. Further, in order to impart printability and adhesiveness to the laminated polyamide film of the present invention, the film surface is subjected to a corona discharge treatment, a plasma treatment, an ultraviolet irradiation treatment, a flame treatment, or a polymer layer applied by means such as coating. Can be.

Next, examples of the inorganic vapor-deposited layer constituting the gas barrier layer include silicon oxide, aluminum oxide, magnesium oxide and a mixture thereof. The term “silicon oxide” used herein refers to a mixture of various silicon oxides such as SiO and SiO ₂ , and the term “aluminum oxide” refers to AlO or Al
Consisting of a mixture of various aluminum oxides such as ₂ O ₃ ,
The amount of oxygen bonded in each oxide varies depending on the manufacturing conditions.

In the present invention, a mixture of silicon oxide and aluminum oxide in which the content of aluminum oxide in the gas barrier layer is 5% by weight or more and 45% by weight or less is preferable.
If the amount of aluminum oxide in the silicon oxide / aluminum oxide-based deposited film is less than 5% by weight, there is a problem that lattice defects occur in the deposited film and a sufficient gas barrier property cannot be obtained. When the amount of aluminum oxide in the deposited film exceeds 45% by weight, the flexibility of the film is reduced, and the film is easily broken (cracked or peeled) due to a dimensional change at the time of hot water treatment, and the barrier property is reduced. A problem arises that does not meet the purpose of the present invention. A more preferable ratio of the aluminum oxide is 10% by weight or more and 35% by weight or less, further preferably 15% by weight or more and 25% by weight or less. In the gas barrier layer, a trace amount of other oxides or the like (at most 3% by weight) is added as long as the properties are not impaired.
Up to). The thickness of the gas barrier layer composed of silicon oxide and aluminum oxide is usually 10 to 10.
5,000, preferably 50-2,000,
If the film thickness is less than 10 °, it is difficult to obtain a satisfactory gas barrier property, and if it exceeds 5,000 °, the effect of improving the gas barrier property corresponding thereto cannot be obtained, and the bending resistance and the production cost are reduced. It is disadvantageous.

For the production of a silicon oxide / aluminum oxide based deposited film, a physical vapor deposition method such as a vacuum vapor deposition method, a sputtering method, an ion plating method, or a chemical vapor deposition method such as a CVD method is appropriately used. For example, when a vacuum deposition method is employed, a mixture of SiO ₂ and Al ₂ O ₃ or a mixture of SiO ₂ and Al is used as a deposition material.
Heating can be performed by resistance heating, induction heating, electron beam heating, etc. In addition, oxygen, nitrogen, hydrogen, argon, carbon dioxide, water vapor, etc. are introduced as a reaction gas, ozone addition, ion assist, etc. It is also possible to employ reactive vapor deposition using the above means. Further, the film forming conditions such as applying a bias to the substrate, heating and cooling the substrate, and the like can be arbitrarily changed. The above-mentioned deposition material, reaction gas,
Substrate bias, heating / cooling, etc.
The same applies to the case where the VD method is adopted.

Before or during the vapor deposition, the surface of the polyamide resin film serving as a base layer is subjected to a corona treatment, a flame treatment, a low-temperature plasma treatment, a glow discharge treatment, a reverse sputtering treatment, a roughening treatment, etc. It is also effective to improve the adhesion strength of the film. By using a silicon oxide / aluminum oxide-based thin film having such a component composition, it is possible to obtain a gas barrier film that is transparent and has excellent performance that can withstand a boiling treatment and a gelbo test (bending resistance test).

The gas barrier properties of the laminated film according to the present invention are greatly related to the adhesion strength between the polyamide resin film serving as the base layer and the gas barrier layer, and the higher the adhesion strength, the better the gas barrier properties. According to the study results of the present inventors, in order to have excellent gas barrier properties and maintain the excellent gas barrier properties even after the boiling treatment, the adhesion strength after the boiling treatment should be 100 g / 1.
It has been confirmed that it should be 5 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 / 1.
5 mm or more. When the adhesion strength is less than 100 g / 15 mm, the gas barrier property tends to be deteriorated by the boiling treatment. It is considered that the reason for this is that if the adhesion strength is high, the inorganic vapor deposition layer is less likely to be peeled off even when the vapor deposition base material slightly shrinks due to boiling treatment or retort treatment.

Means for obtaining such excellent adhesion strength include a corona treatment, a plasma treatment, a glow discharge treatment, a reverse sputtering treatment, a roughening treatment on the surface of a polyamide resin film which is a base layer of an inorganic vapor deposition layer. Processing, etc.
Alternatively, there is a method of forming an anchor coat layer on a polyamide-based resin film for improving adhesion, but of course, the method is not limited to these methods.

The anchor coating agent preferably used for improving the adhesion strength includes a reactive polyester resin, an oil-modified alkyd resin, a urethane-modified alkyd resin,
Melamine-modified alkyd resin, epoxy cured acrylic resin, epoxy resin (using amine, carboxyl group-terminated polyester, phenol, isocyanate, etc. as curing agent), isocyanate resin (amine, urea, carboxylic acid, etc. as curing agent) ), Urethane-polyester resin, polyurethane resin, phenol resin, polyester resin, polyamide resin, reactive acrylic resin, vinyl acetate resin, vinyl chloride resin and the like and copolymers thereof. These can also be used as aqueous resins solubilized or dispersed in water. In addition, it is also effective to use an inorganic coating agent such as a silane coupling agent as the anchor coating agent.

The method for forming the anchor coat layer is as follows.
Either an in-line method of applying the polyamide resin film at the time of production or an off-line method of applying the polyamide resin film in a separate step from the production of the polyamide resin film can be adopted. For the coating, a known coating method, for example, 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, a curtain coating method, or the like can be adopted.

According to the study results of the present inventors, in order to improve the adhesion strength between the base layer and the inorganic vapor-deposited layer by forming the anchor coat layer, use of an aqueous polyester resin from the viewpoint of cost and hygiene. preferable. Such a polyester resin is obtained by polycondensing a dicarboxylic acid or a tricarboxylic acid with a glycol. Examples of the components used for the polycondensation include acid components such as terephthalic acid, isophthalic acid, adipic acid, and trimellitic acid, and glycol components such as ethylene glycol, neopentyl glycol, butanediol, and ethylene glycol-modified bisphenol A. However, of course, it is not limited to these. The polyester resin may be obtained by graft copolymerization of an acrylic monomer. The preferred thickness of the anchor coat layer is 0.01
10 to 10 μm, more preferably 0.02 to 5 μm,
If the thickness is less than 0.02 μm, the effect of improving the adhesive strength tends to be hardly exhibited, and even if the thickness is more than 5 μm, no further effect of improving the adhesiveness is exhibited,
It is economically disadvantageous.

On the surface of the above-mentioned inorganic vapor-deposited layer, a heat seal layer made of a polyolefin resin for providing thermal adhesion is formed as a main purpose, and the heat seal layer serves as a protective layer for the inorganic vapor-deposited layer. It also has functions,
In performing its function effectively, it is extremely effective to increase the adhesive strength between the inorganic vapor-deposited layer and the heat seal layer.
As a means for that, it is extremely effective to provide an adhesive layer between the inorganic vapor deposition layer and the heat seal layer.

The polyolefin resin constituting the heat seal layer does not necessarily have to be a single layer, but may be a multilayer. The resin constituting each layer when forming a multilayer structure is also
Not only a combination of resins of the same kind but also a laminate of a copolymer, a modified product, a blend, or the like of different polymers. For example, in order to enhance the laminating property and the heat sealing property, a polymer having a glass transition temperature (Tg) or a melting point lower than that of the thermoplastic polyolefin resin as a base is compounded, and in order to impart heat resistance, the Tg or the melting point is decreased. It is also possible to composite high polymers.

Various additives such as a plasticizer, a heat stabilizer, an ultraviolet absorber, an antioxidant, a colorant, a filler, an antistatic agent, and the like may be added to the polyolefin resin constituting the heat seal layer, if necessary. It is also possible to blend antibacterial agents, lubricants, antiblocking agents, other resins, and the like.

Particularly preferred as the resin constituting the adhesive layer is a resin having a glass transition temperature in the range of -10 ° C to 40 ° C, for example, a polyurethane resin, a polyester resin, an epoxy resin, a vinyl chloride resin, acetic acid. Vinyl resins, polyethylene resins, polypropylene resins, melamine resins, acrylic resins, etc., which can be used alone or, if necessary, in combination of two or more, or by melting and mixing, or Examples of the group include a carboxylic acid group, an acid anhydride, (meth) acrylic acid and (meth) acrylic acid.
An adhesive composition containing a compound having an acrylate ester skeleton; an epoxy compound containing a glycidyl group or a glycidyl ether group; a curing agent or a curing accelerator having a reactive functional group such as an oxazoline group, an isocyanate group, an amino group, or a hydroxyl group. It is also effective to use.

The lamination of the polyolefin resin is formed as a heat seal layer on the inorganic vapor-deposited layer by a dry lamination method or a wet lamination method using an adhesive, and further by a melt extrusion lamination method or a co-extrusion lamination method. You.

The thus obtained gas-barrier laminated film or sheet of the present invention makes use of its excellent gas-barrier properties, gas-barrier durability by boiling treatment and retort treatment and secondary processing characteristics, and is used as a packaging material for miso, pickles, prepared dishes, baby foods. Food, tsukudani, konjac, chikuwa,
Kamaboko, processed fishery products, meatballs, hamburgers, genghis khan, ham, sausage, other processed meat products, tea,
Oil confectionery such as coffee, tea, bonito, kelp, potato chips, and butter peanuts, rice crackers, biscuits, cookies, cakes, buns, castella, cheese, butter, cut rice cake, soups, sauces, ramen, wasabi, toothpaste, etc. It can be effectively used for packaging of pet foods, agricultural chemicals, fertilizers, infusion packs, and also for industrial materials such as semiconductors and precision material packaging, such as medical, electronic, chemical, and machinery. Can be. The form of the packaging material is not particularly limited, and can be widely applied to bags, lid materials, cups, tubes, standing packs, and the like.

(Examples) Next, the present invention will be described specifically with reference to examples. The present invention is naturally not limited by the following examples, and it is of course possible to implement the present invention with appropriate modifications within a range that can be adapted to the spirits of the preceding and the following. Is included. Various performance tests adopted in the following examples were performed by the following methods.

Oxygen permeability: Oxygen permeability measuring device (“OX
-TRAN 10 / 50A (manufactured by Modern Controls) at a humidity of 0% and a temperature of 25 ° C.

Water vapor transmission rate: Measured at a humidity of 0% and a temperature of 25 ° C. using a water vapor transmission rate measuring apparatus (“PERMATRAN” manufactured by Modern Controls).

Adhesion strength: The laminated product was peeled off by 180 ° using “Tensilon UTM2” manufactured by Toyo Sokki Co., Ltd. while adhering water to the interface, and the S between the gas barrier layer and the base material was removed.
It was determined by measuring the -S curve.

Bending fatigue test: Bending fatigue test (hereinafter referred to as "bending fatigue test")
Gelbo test) was evaluated using a gelbo flex tester manufactured by Rigaku Corporation. The condition is (MIL-B1
31H) A 12-inch × 8-inch test piece was 3 (1/1/3)
2) It is a cylindrical shape of inch, holding both ends, making an initial grasping interval of 7 inches, and setting a stroke of 3 (1/2) inch to 4 inches.
Add a 00 degree twist. This operation is repeated 1000 times at a speed of 40 times / min. The measurement atmosphere is 20 ° C. and the relative humidity is 65%. The number of pinholes at this time was counted.

Example 1 40 parts by weight of nylon 6, nylon 6T / nylon 6 copolymer (copolymerization ratio)
50/50) 60 parts by weight of the mixture is melt extruded while being laminated from a T-die, cooled on a rotating drum at 20 ° C.
m of unstretched polyamide film was obtained. This unstretched film was longitudinally stretched 3.1 times at 90 ° C. The film is then stretched 3.3 times in the horizontal direction at 135 ° C, heat-set at 215 ° C, and
Was obtained. At the same time, apply a polyester coating agent (“AGN131” manufactured by Toyobo Co., Ltd.) to about 0.1 μm.
Coated. This film was excellent in both bending fatigue resistance and adhesiveness. This film is sent to a vacuum deposition apparatus, and the inside of the chamber is maintained at a pressure of 1 × 10 ⁻⁵ Torr, and a mixed oxide of 70% by weight of SiO ₂ and 30% by weight of Al ₂ O ₃ is evaporated by electron beam heating of 15 Kw. Let the thickness 2
A colorless and transparent inorganic oxide layer of 00 ° was deposited on the coating surface to form an inorganic deposited layer. Next, unstretched polyethylene (thickness:
55 μm) with an adhesive (“A310 / A1 manufactured by Takeda Pharmaceutical Co., Ltd.)
0 ", dry-laminated at a coating amount of 2 g / m ^{2, and} aged at 45 ° C for 4 days to obtain a gas barrier resin film. This gas barrier resin film is (1) immersed in hot water of 95 ° C. and stretched after 30 minutes (%). (2) immersed in hot water of 95 ° C. and left in the air for 15 minutes. Shrinkage after (%) (3) Oxygen permeability of untreated film (cc / m ² · atm · day) (4) Oxygen permeability of film after immersion in hot water of 95 ° C for 30 minutes and left for 1 hour Degree (cc / m ² · atm day) (5) After immersion in hot water of 95 ° C for 30 minutes, water vapor permeability (g / m ² · day) of the film after standing for 1 hour (6) Heat of 95 ° C After immersion in water for 30 minutes, the adhesion force (g / 15 mm) when water was dropped onto the peeling interface of the film after standing for 1 hour (7) The number of pinholes (pieces) after the bending fatigue test was measured.

(Example 2) In the method of Example 1, 25
Nylon 6, Nylon 6T / Nylon 6 copolymer (copolymerization ratio 50/50) except that it is a mixture of 75 parts by weight,
The operation was performed in exactly the same manner as in Example 1.

Example 3 In the method of Example 1, a nylon 6T / nylon 6 copolymer (copolymerization ratio 50/50) 10
0 parts, the longitudinal stretching temperature was 120 ° C, and the transverse stretching temperature was 150 ° C.
The procedure was exactly the same as in Example 1 except that the temperature was changed to ° C.

(Comparative Example 1) In the method of Example 1, 1
The procedure was exactly the same as in Example 1 except that the nylon 6 was used in an amount of 00 parts by weight, the temperature for longitudinal stretching was 50 ° C., and the temperature for transverse stretching was 125 ° C.

(Comparative Example 2) In the method of Example 1, 75
The procedure was performed except that a mixture of 25 parts by weight of nylon 6 and nylon 6T / nylon 6 copolymer (copolymerization ratio: 50/50) was used and the temperature for longitudinal stretching was 70 ° C and the temperature for transverse stretching was 125 ° C. The procedure was exactly the same as in Example 1.

[0035]

[Table 1] (1) Shrinkage rate after immersion in hot water of 95 ° C and 30 minutes (%) (2) Shrinkage rate after immersion in hot water of 95 ° C and left in air for 15 minutes (%) (3) untreated oxygen permeability of the film ^{(cc / m 2 · atm ·} day) (4) 30 minutes after immersion in hot water at 95 ° C., 1h after standing film oxygen permeability (cc / m ² · atm · day) (5) After immersion in hot water at 95 ° C for 30 minutes, water vapor permeability of the film after standing for 1 hour (g / m ² · day) (6) After immersion in hot water at 95 ° C for 30 minutes 1. Adhesion force when water is dropped on the peeling interface of the film after standing for 1 hour (g / 15mm) (7) Number of pinholes after bending fatigue test (pieces)

[0036]

The gas barrier laminate film of the present invention is
There is little dimensional change in boil treatment, and there is little peeling and cracking of the gas barrier layer. In particular, the present inventors have conducted intensive studies,
The inventors have found that it is important for maintaining good barrier properties that the elongation of the laminated film in the boil is small and the shrinkage after the boil is not more than a certain value, leading to the present invention. It was found that the laminated film using the nylon film as the base layer stretched in the boil. At this time, cracks occur in the gas barrier layer, which itself causes a decrease in gas barrier properties. In addition, it is considered that peeling occurs, and that the gas barrier property further decreases. Although the area of cracks is reduced by shrinkage after boiling, it is considered that the gas barrier layer is broken when the area exceeds a certain value. Therefore, if the dimensional change of the laminated film in and after the boiling is within the range of the present invention, it is considered that good barrier properties are maintained.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tadashi Sugimoto 2-1-1 Katata, Otsu City, Shiga Prefecture Inside Toyobo Co., Ltd. (72) Inventor Seiichiro Yokoyama 2-1-1 Katata, Otsu City, Shiga Prefecture Inside Toyobo Co., Ltd. (72) Inventor Seiji Iseki 2-1-1 Katata, Otsu-shi, Shiga Prefecture Inside Toyobo Co., Ltd. (72) Inventor Yozo Yamada 2-1-1 Katata, Otsu-shi, Shiga Prefecture Inside Toyobo Co., Ltd. (72) Inventor Jikao Morishige 2-1-1 Katata, Otsu-shi, Shiga F-term inside Toyobo Co., Ltd. (Ref.) 4F100 AA17B AA19B AA20B AK03C AK04C AK46A AK48A AL01A AL05A BA03 BA07 BA10A BA10C CA30A EH66B EJ38A GB15 JA03 JD02B JD04 JJ03 JK08 JL04 JL05 JM02B JN01 YY00

Claims (5)

[Claims] A gas barrier layer comprising a metal oxide thin film layer formed on a polyamide film and a polyolefin film laminated on the metal oxide thin film layer, wherein the gas barrier laminated film satisfies the following conditions: . (1) It is immersed in hot water of 95 ° C. and has an elongation of 1% or less after 30 minutes. (2) The shrinkage after immersion in hot water of 95 ° C. for 15 minutes in air is 3% or less. 2. A polyamide film comprising the following X: 30 to 10
The gas barrier laminate film according to claim 1, comprising a polyamide resin composition obtained by blending 0 parts by weight, 70 to 0 parts by weight of Y, and 0 to 10 parts by weight of Z. (X): a mixture and / or copolymer of an aromatic polyamide resin component (a) composed of terephthalic acid or isophthalic acid and an aliphatic diamine and an aliphatic polyamide resin (b), wherein the aromatic polyamide resin component ( (Y): aliphatic polyamide-based resin (Z): flex fatigue resistance improving agent 3. The gas barrier laminate film according to claim 1, wherein an easy-adhesion layer for improving adhesion strength is laminated between the laminated polyamide film and the inorganic metal thin film layer. 4. The gas barrier laminate film according to claim 2, wherein the metal oxide thin film layer is a mixture thin film layer of silicon oxide and aluminum oxide. 5. The gas barrier laminate film according to claim 4, wherein the aluminum oxide in the mixture of silicon oxide and aluminum oxide in the metal oxide thin film layer is from 5% by weight to 45% by weight.