JP7156592B2 - Gas barrier aluminum deposition film and laminated film using the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a gas barrier aluminum deposited film having excellent oxygen and water vapor barrier properties, lamination strength, bending resistance and tensile resistance.

Packaging materials using aluminum foil, in addition to the metallic luster of the design, have light shielding properties and excellent gas barrier performance. It is used as an outer layer packaging material for vacuum insulation materials such as insulation panels for However, packaging materials using aluminum foil have problems in that handling of the aluminum foil is difficult because pinholes are likely to occur, and the residue after incineration places a large load on the incinerator.

In order to solve the above-mentioned problems of aluminum foil, an aluminum vapor-deposited film obtained by using a physical vapor deposition method such as a vacuum vapor deposition method on a thermoplastic film such as a polyester film is used as a substitute for the aluminum foil. However, aluminum-deposited films have insufficient gas barrier performance for boiled/retort food applications, and the vapor-deposited aluminum layer disappears during boil/retort sterilization, resulting in a significant deterioration in gas barrier performance, making them unusable. .

As a gas barrier film for boiled and retort food applications, a gas barrier film is disclosed in which a vapor deposition layer composed of an inorganic oxide or inorganic nitride and a specific resin layer are laminated on at least one side of a plastic film. (See Patent Document 1, for example).

In order to improve the alkali boiling resistance and acetic acid retort resistance of the aluminum vapor deposition film and suppress changes in the appearance of the aluminum vapor deposition layer, the substrate (a), the metal vapor deposition layer (b) and the protective layer (c) are arranged in this order. and the protective layer (c) contains a specific dimer acid-based polyamide resin (see, for example, Patent Document 2).

On the other hand, the thermal conductivity of aluminum is about 200 W/m K, which is about 0.14 W/m K, which is the thermal conductivity of polyethylene terephthalate, which is a typical packaging material, and about 0 W/m K, which is the thermal conductivity of air. Since it is larger than 0.02 W/m·K, heat bridges occur where heat is transferred through the aluminum foil portion of the heat insulating material laminated with aluminum foil, and the heat insulating performance of the vacuum heat insulating material is greatly reduced. was there. In addition, films for vacuum insulation materials are required to have excellent gas barrier performance in order to prevent gas (air) from entering from the outside and to maintain a vacuum state for a long period of time. Furthermore, in recent years, the fins around the vacuum insulation material (welded and sealed parts) have lower insulation performance than the part containing the core material, and the fins are bent to maintain the overall insulation performance. Also, the vacuum insulation material itself is deformed according to the shape of the storage space when it is used in a place with a complicated shape (for example, an arc shape or a right angle shape). In view of the above, it is also required that the film for vacuum insulation material does not deteriorate in gas barrier performance when it is bent or deformed.

In order to solve the problem of aluminum foil in vacuum insulation applications, that is, in order to achieve both reduction of heat bridges and improvement of gas barrier properties of the vacuum insulation material, a vapor deposition layer composed of an inorganic oxide or inorganic nitride and a specific A vacuum heat insulating material has been developed in which a gas barrier film laminated with a resin layer is laminated (see, for example, Patent Document 3). Also, a film for a vacuum heat insulating material has been proposed in which two transparent barrier films are laminated with a polyolefin resin by extrusion lamination (see, for example, Patent Document 4).

JP 2010-131756 A JP 2012-210744 A Japanese Patent Application Laid-Open No. 2005-132004 JP 2007-290222 A

However, the gas barrier film according to Patent Document 1 is a transparent gas barrier film and does not replace aluminum foil.

The laminate according to Patent Document 2 did not have sufficient gas barrier performance.

The vacuum insulation material according to Patent Document 3 is a transparent gas barrier film, and for radiation among heat conduction, heat is transmitted as infrared rays, and heat is conducted even in a vacuum. was not good enough.

The film for a vacuum heat insulating material according to Patent Document 4 has a problem that the heat of the polyolefin resin extruded into the transparent barrier film deteriorates the vapor deposition layer and lowers the gas barrier properties.

An object of the present invention is to provide a gas-barrier aluminum vapor-deposited film having excellent oxygen and water vapor barrier properties, lamination strength, bending resistance and tensile resistance, and a laminated film using the same.

In order to solve the above problems, the present invention has the following configurations.

(1) A deposited layer whose composition changes continuously from an aluminum metal layer with a thickness of 25 nm or more and 125 nm or less to an aluminum oxide layer with a thickness of 5 nm or more and 25 nm or less is formed on at least one side of the substrate film surface, Furthermore, a gas barrier resin layer having a thickness of 0.1 to 4 μm is laminated thereon, and the gas barrier resin layer is made of a gas barrier composition obtained by polycondensation of a vinyl alcohol resin and an organic silicon compound having an alkoxy group. In addition, the adhesive strength between the vapor deposition layer and the gas barrier resin layer is 3.0 N/15 mm or more, the water vapor transmission rate after 5% tension is 0.1 g/m ² ·24 hr or less, and the oxygen transmission rate is 0.1 g/m 2 ·24 hr or less. 1 cc/m ² ·24 hr·atm or less, a water vapor transmission rate after a bending fatigue test of 0.5 g/m ² ·24 hr or less, and an oxygen transmission rate of 0.2 cc/m ² ·24 hr·atm or less. A gas-barrier aluminum vapor-deposited film characterized by having an infrared reflectance of 60% or more measured at a relative reflection angle of 12 degrees using an infrared spectrophotometer .

( 2 ) A laminated film comprising a sealant film, a gas-barrier film and a plastic film laminated in this order, wherein the gas-barrier film comprises the gas-barrier aluminum-deposited film according to any one of the above.

INDUSTRIAL APPLICABILITY According to the present invention, a gas barrier aluminum vapor-deposited film having excellent oxygen and water vapor barrier properties, lamination strength, bending resistance and tensile resistance, and a laminated film using the same can be obtained.

The present invention will be described in detail below.

In the gas-barrier aluminum vapor-deposited film of the present invention, a vapor-deposited layer whose composition changes continuously from an aluminum metal layer with a thickness of 25 nm or more to an aluminum oxide layer with a thickness of 5 nm or more is formed on at least one side of the substrate film surface. Furthermore, a gas barrier resin layer having a thickness of 0.1 to 4 μm is laminated thereon, and the gas barrier resin layer is made of a gas barrier composition obtained by polycondensation of a vinyl alcohol resin and an organic silicon compound having an alkoxy group. characterized by becoming

As described in Background Art, the gas barrier performance of conventional aluminum vapor deposition films is inadequate compared to aluminum foil. By providing a layer, not only does the imperfect gas barrier performance of the aluminum metal layer be compensated for, but the aluminum oxide vapor deposition layer exerts the effect of a layer that strengthens the adhesion between the vapor deposition layer and the gas barrier resin layer, and the resin that constitutes the gas barrier resin layer. exhibits its inherent gas barrier performance.

[Base film]
As the base film for the gas barrier aluminum vapor-deposited film of the present invention, as long as characteristics such as chemical resistance, mechanical strength (film stiffness, external abrasion, puncture strength), heat resistance, and weather resistance are taken into consideration depending on the application. Although not particularly limited, for example, polyethylene terephthalate film, polypropylene film, nylon film and the like are used. A polyethylene terephthalate film is preferred for practical use.

The substrate film may be an unstretched film, but a stretched (uniaxially or biaxially) film is usually excellent in mechanical properties and thickness uniformity, and a biaxially stretched film is more preferable. As the stretching method, conventional stretching methods such as roll stretching, roll stretching, belt stretching, tenter stretching, tube stretching, and stretching in combination thereof can be applied.

Although the thickness of the base film is not particularly limited, it is practically about 6 μm to 30 μm for polyethylene terephthalate film, about 20 μm to 40 μm for polypropylene film, and about 10 μm to 30 μm for nylon film.

[Vapor deposition layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer]
In the present invention, a deposited layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer is formed on the substrate film. A vapor deposition layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer is a vapor deposition layer having a gradient structure in which an aluminum metal layer is formed at the beginning of vapor deposition and changes to aluminum oxide as the film grows. By the way, in the vapor deposited aluminum layer, a thin natural oxide film is formed on the surface of the aluminum metal film when it is taken out to the atmosphere after vapor deposition. This natural oxide film is at most about 3 nm. It is 5 nm or more according to the analysis method. It is preferably 10 to 25 nm. If it exceeds 25 nm, the metallic appearance of the aluminum metal layer may be impaired, and the infrared reflectance may be lowered.

It is important that the film thickness of the aluminum metal layer is 25 nm or more. If the thickness is less than 25 nm, the gas barrier performance may be insufficient, and the metallic appearance may be insufficient. Moreover, in vacuum heat insulating material applications, the infrared reflectance may be less than 60%, resulting in insufficient heat insulating performance. It is preferably 40 to 125 nm. Even if it exceeds 125 nm, the gas barrier performance reaches a ceiling, and the cohesive energy during vapor deposition of the aluminum metal layer increases, the substrate film is deformed by heat, and the appearance may not be practical.

It is preferable that the total thickness of the deposition layer whose composition changes continuously from the aluminum metal layer to the aluminum oxide layer is 30 to 150 nm. If the film thickness is less than 30 nm, it is difficult to achieve the desired oxygen barrier performance and water vapor barrier performance. If the thickness is 150 nm or more, the cohesive force of the vapor deposition layer is lowered, and peeling is caused by cohesive failure within the vapor deposition layer, resulting in a low apparent lamination strength. In addition, the cohesive energy during vapor deposition increases, the substrate film is deformed by heat, and the appearance may become unusable.

A preferred method for forming a deposited layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer is a method in which a deposited layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer is formed in a vacuum chamber. The vapor deposition may be carried out by known methods such as vapor deposition and sputtering, but the vapor deposition method is preferable from the viewpoint of productivity, and the heating and vaporization of aluminum for that purpose is a method such as resistance heating, high frequency heating, or electron beam heating. is applicable. In these vapor deposition methods, it is preferable to form a vapor deposition layer whose composition changes continuously from an aluminum metal layer to an aluminum oxide layer by reactive vapor deposition. That is, the base film is generally long and is supplied in a roll, is unwound from the roll in a vacuum chamber, vapor deposition is performed, and is wound again into a roll. An aluminum metal layer is formed, oxygen is introduced in the latter part of the deposition, and aluminum oxide is formed by the reaction of metallic aluminum and oxygen. Oxygen introduced in the second half of vapor deposition diffuses from the winding side of the substrate film toward the unwinding side, so that the metal aluminum layer and the aluminum oxide layer are not strictly separated from each other. Oxygen reacts continuously from the aluminum metal layer to the aluminum oxide layer according to the position of the vapor deposition zone through which the film passes, forming a gradient structure in which the composition continuously changes in the film thickness direction.

[Gas barrier resin layer]
In the present invention, the gas barrier resin layer is formed by applying a gas barrier resin obtained by polycondensation of a vinyl alcohol resin and an organic silicon compound having an alkoxy group. As a result, it is possible to protect the deposited aluminum layer, which is the base layer, and improve the gas barrier properties. That is, the vapor-deposited layer made of aluminum metal and aluminum oxide may have defects such as pinholes, cracks, and grain boundaries, which may deteriorate the gas barrier properties. can be compensated for and the gas barrier performance itself can be strengthened.

A specific method for forming the gas-barrier resin layer is an aqueous solution containing either an organosilicon compound having an alkoxy group or a hydrolyzate thereof, which is based on a vinyl alcohol-based resin that has a high affinity for the deposited layer, or Formed from an alcohol mixed aqueous solution.

The vinyl alcohol-based resin as the base material for forming the gas barrier resin layer is not particularly limited as long as it is a vinyl alcohol-based resin such as polyvinyl alcohol, ethylene-vinyl alcohol copolymer, modified polyvinyl alcohol, and the like. Among them, it is particularly preferable to use polyvinyl alcohol in the coating agent of the present invention because it has excellent gas barrier properties. Polyvinyl alcohol here is generally obtained by saponifying polyvinyl acetate, and may be partially saponified obtained by saponifying a part of the acetic acid group or completely saponified, and is not particularly limited. . An organic silicon compound having an alkoxy group is further added to the coating material for forming the gas barrier resin layer. An alkoxy group has a structure of RO- in which an alkyl group R is bonded to oxygen, and is changed to a silanol group through a dealcoholization reaction by hydrolysis, and a methoxy group or an ethoxy group is typical. is. These silicon compounds having an alkoxy group are specifically tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, n-propyltrimethoxysilane, n- Examples include propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, etc. Among them, tetraethoxysilane is preferred because it is relatively stable in an aqueous solvent after hydrolysis.

The mixing ratio of the organosilicon compound having an alkoxy group to the vinyl alcohol resin is preferably in the range of vinyl alcohol resin/organosilicon compound = 15/85 to 85/15 in terms of mass ratio of the organosilicon compound converted to _SiO2 . A range of 40/60 to 60/40 is more preferred. The mass ratio in terms of SiO ₂ is obtained by converting the number of moles of silicon atoms in the organosilicon compound into the mass of SiO ₂ , and is represented by vinyl alcohol resin/organosilicon compound (mass ratio). If this value exceeds 85/15, the vinyl alcohol-based resin cannot be immobilized, and the gas barrier performance may deteriorate. On the other hand, if it is less than 15/85, the ratio of the organosilicon compound will increase and the gas barrier resin layer will become hard, which may result in a decrease in flex resistance and tensile performance.

In the present invention, the gas barrier resin layer is formed using an aqueous solution containing at least one of the vinyl alcohol resin and at least one of the above organosilicon compounds having an alkoxy group and a hydrolyzate thereof, or a coating agent consisting of an alcohol-mixed aqueous solution. be done. The above vinyl alcohol resin alone has excellent barrier performance against gases such as oxygen and nitrogen because the hydroxyl groups in the molecular chains are bound by hydrogen bonds during the process of solidifying as a coating film. However, the barrier performance cannot be expressed for water molecules because the hydrogen bonds are plasticized. By forming a resin composition comprising a vinyl alcohol-based resin and an organic silicon compound having an alkoxy group, an inorganic structure having a skeleton of a siloxane bond formed by polycondensation between the organic silicon compounds and a hydroxyl group of the vinyl alcohol-based resin can form hydrogen atoms. A so-called organic-inorganic hybrid structure having a covalent bond of Si--O-- through a bond and a dehydration reaction appears. In such a structure, the restraint of the molecular chains is stronger than that of a single vinyl alcohol-based resin, and the water vapor barrier performance can be exhibited. Furthermore, it is possible to form a dense structure by bonding with hydroxyl groups on the surface of the deposited film to improve adhesion, and by filling and reinforcing defects such as pinholes, cracks, and grain boundaries in the deposited layer. , the deterioration of the gas barrier performance can be suppressed during bending or deformation.

[Formation of gas barrier resin layer]
The method for forming the gas barrier resin layer in the present invention is not particularly limited, and can be formed by a method suitable for the substrate film. For example, printing methods such as offset printing method, gravure printing method, silk screen printing method, roll coating method, dip coating method, bar coating method, die coating method, knife edge coating method, gravure coating method, kiss coating method, spin coating method etc., or a combination of these methods may be used to coat the coating liquid.

The film thickness of the gas barrier resin layer provided on the deposited layer whose composition changes continuously from the aluminum metal layer to the aluminum oxide layer should be 0.1 to 4 μm, more preferably 0.2 to 1 μm.

If the film thickness of the gas barrier resin layer is 0.1 μm or less, gas barrier performance may not be exhibited. On the other hand, when the thickness of the gas barrier resin layer exceeds 4 μm, the cohesive force of the gas barrier resin layer is reduced, and peeling is caused by cohesive failure within the gas barrier resin layer, resulting in a decrease in apparent lamination strength. Moreover, high temperature and long time are required for drying the coating, which raises the problem that the manufacturing cost rises.

[Laminated film]
The laminated film produced using the gas barrier aluminum deposited film of the present invention is formed by laminating a sealant film as a heat-sealable layer, a gas barrier film and a plastic film as a surface protective layer in this order.

Depending on the application, the sealant film is not particularly limited as long as properties such as chemical resistance, mechanical strength (film stiffness, external abrasion, puncture resistance), heat resistance, weather resistance, etc. are taken into account, but polypropylene film, polyethylene film etc. are used. A polyethylene film is preferred for practical use, and a linear low-density polyethylene film is particularly preferred.

The vapor-deposited surface of the gas-barrier aluminum vapor-deposited film, which is a gas-barrier film, may be the plastic film side or the sealant film side, which is selected according to the design. If necessary, the gas barrier film may be a laminate of a plurality of gas barrier aluminum deposited films. Alternatively, the deposition surface and the substrate film surface may be bonded together. When a plurality of these gas-barrier aluminum vapor-deposited films are laminated, the laminate film of the present invention is constructed by laminating a sealant film on one side of the laminate and a plastic film on the other side.

The plastic film is not particularly limited as long as properties such as chemical resistance, mechanical strength (film stiffness, external abrasion, piercing strength), heat resistance, and weather resistance are taken into account, but examples include polyethylene terephthalate film, A polypropylene film, a nylon film, etc. are used. An unstretched film may be used, but a biaxially stretched film is more preferable because a film that is usually stretched (uniaxially or biaxially) is excellent in mechanical properties and thickness uniformity. Although the thickness is not particularly limited, it is practically about 6 μm to 30 μm for polyethylene terephthalate film, about 20 μm to 40 μm for polypropylene film, and about 10 μm to 30 μm for nylon film.

A laminate of a plurality of these plastic films may be used as the surface protective layer as required.

As a method for producing a laminated film using the gas barrier aluminum vapor-deposited film of the present invention, a dry lamination method using a two-liquid curing urethane adhesive, an extrusion lamination method, or the like can be employed, but there are particular restrictions. not a thing

EXAMPLES Hereinafter, examples will be given to describe the present invention in detail, but the present invention is not limited to the examples.

(Evaluation method)
(1) Adhesion strength between vapor deposition layer and gas barrier resin layer (N/15 mm)
A 40 μm-thick sealant film was applied to the vapor-deposited surface of the gas-barrier film via an adhesive consisting of a polyester urethane-based main agent (manufactured by DIC Corporation, LX500) and an aromatic isocyanate curing agent (manufactured by DIC Corporation, KW75). A laminated film was prepared by laminating the linear low-density polyethylene films of No. 1 by the dry lamination method. Next, the laminated film was cut to a width of 15 mm and a length of 150 mm to prepare a cut sample, and a tensile tester (Tensilon) was used to determine the interface between the gas barrier film and the linear low-density polyethylene film by the T-peel method. The peel strength (laminate strength) was measured at a tensile speed of 50 mm/min, and the adhesion strength between the vapor deposition layer and the gas barrier resin layer was evaluated. A value of adhesion strength of 3.0 N/15 mm or more was considered acceptable.

( ² ) Oxygen permeability (cc/m2.24hr.atm)
The gas barrier film is measured at a temperature of 23° C. and a humidity of 0% RH using an oxygen permeability meter (OXTRAN 2/20) manufactured by MOCON, USA, based on the isobaric method described in JIS K7126-2:2006. Oxygen permeability was measured. A value of oxygen transmission rate of 0.1 cc/m ² ·24 hr·atm or less was considered acceptable.

(3) Water vapor transmission rate (g/m ² 24 hr)
A gas barrier film is measured at a temperature of 40° C. and a humidity of 90% RH using an oxygen permeability meter (PERMATRAN W3/31) manufactured by MOCON in the United States according to the infrared sensor method described in JIS K7129:2008 Appendix B. The water vapor transmission rate was measured based on. A water vapor transmission rate of 0.1 g/m ² ·24 hr or less was considered acceptable.

(4) Infrared reflectance (%)
Using an infrared spectrophotometer (U-4000, Hitachi High-Technologies Co., Ltd.), the gas barrier film is reflected in the wavelength range of 240 nm to 2600 nm including the infrared wavelength range at a relative reflection angle of 12 degrees of the reflector. Light intensity was measured. Of these, the ratio of the reflected light intensity of the gas barrier film to the reflected light intensity of the aluminum vapor-deposited plane mirror used as a reference for the reflected light intensity at the three points of wavelengths 1500 nm, 2000 nm, and 2500 nm is defined as the infrared reflectance (%). The average value of the points was calculated. The closer this value is to 100%, the better the reflective properties are, and the value of infrared reflectance of 60% or more was considered acceptable.

(5) Oxygen Permeability and Water Vapor Permeability after 5% Stretching Using a test piece that was pulled 5% (7 mm) at a speed of 5 mm/min from both ends of a 90 mm side of a 140 mm x 90 mm test piece of gas barrier film, Oxygen transmission rate and water vapor transmission rate were measured.

(6) Oxygen Permeability and Water Vapor Permeability after Bending Fatigue Test A 200 mm x 300 mm test piece of a gas barrier film was pasted together at both ends of the 300 mm side and rolled into a cylindrical shape, and the both ends of the cylindrical test piece were fixed with a head. and drive head, and while applying a 440 degree twist, narrow the gap between the fixed head and the drive head from 7 inches to 3.5 inches, and while still adding a twist, narrow the gap between the heads to 1 inch, then the head The distance between the heads is widened to 3.5 inches, and the distance between the heads is widened to 7 inches while untwisting at a speed of 40 times/min. The oxygen transmission rate and water vapor transmission rate were measured.

(7) Puncture strength measurement (N)
An adhesive consisting of a polyester urethane-based main agent (LX500, manufactured by DIC Corporation) and an aromatic isocyanate curing agent (KW75, manufactured by DIC Corporation) was applied to the gas barrier film as a sealant film, and a straight-chain thin film having a thickness of 40 μm was applied. A density polyethylene film (T.U.X FC-S manufactured by Mitsui Chemicals Tohcello Co., Ltd.), a 15 μm-thick biaxially oriented nylon film (ONUM manufactured by Unitika Ltd.) as a plastic film, and a vapor-deposited surface of the gas barrier film. A laminate film was produced by laminating by a dry lamination method so that the plastic film side was formed. Next, a 50 mm×50 mm sample piece of the laminated film was used to measure the puncture strength using a tensile tester (Tensilon) based on the method described in JIS Z1707-1997.

(8) Evaporation film thickness measurement Perform depth direction composition analysis evaluation with a scanning Auger electron spectrometer (SAM-670 manufactured by ULVAC-PHI, Inc.), and confirm the film structure of aluminum oxide/metal aluminum by depth profile. did. Focusing on the Al concentration and O concentration, collecting data while performing Ar ion etching from the surface layer of the deposited film, and defining the depth at which the concentration ratio of the Al concentration and O concentration is 50:50 as the interface. The film thicknesses of the aluminum oxide deposition layer and the aluminum deposition layer were calculated. Separately, a metal aluminum film whose film thickness is known by cross-sectional observation with a transmission electron microscope is etched by the same etching method, and the etching rate is calculated to convert the etching time in the above data to the absolute value of the etching depth. did.

(Example 1)
A 12 μm-thick biaxially oriented polyethylene terephthalate film (“Lumirror” (registered trademark) P60 manufactured by Toray Industries, Inc.) was used as the base film, and high-frequency induction heating crucible aluminum was applied using a roll-to-roll vacuum deposition machine. Using an evaporation source, the aluminum metal layer was continuously formed to a thickness of 40 nm and the aluminum oxide layer to a thickness of 10 nm. On the base film, films having a composition corresponding to the position are sequentially formed in the thickness direction within a zone having a constant width in the traveling direction of the base film on a cooled rotating drum. Oxygen was supplied from the last position to be vapor-deposited to form a vapor-deposited layer that continuously changed from an aluminum metal layer to an aluminum oxide layer.

Next, an aqueous solution having the following composition was applied on the vapor-deposited layer obtained above by gravure coating and dried to form a gas barrier resin layer having a thickness of 0.3 μm, thereby producing a gas barrier aluminum vapor-deposited film. The mixing ratio (% by weight) of (solution A)/(solution B) having the following composition was 35/65.

(Aqueous solution for gas barrier resin layer formation)
(Liquid A): Hydrochloric acid (0.1N) was added to tetraethoxysilane (TEOS), and the mixture was stirred for 120 minutes for hydrolysis to prepare liquid A (solid content: 30% by weight, converted to SiO ₂ ).

(B solution): A 10% by weight aqueous solution of polyvinyl alcohol (PVA, degree of polymerization: 1,700, degree of saponification: 98.5%)) and methyl alcohol were blended at a ratio of 35/65 (weight ratio) and stirred. adjusted.

(Example 2)
A gas-barrier aluminum vapor-deposited film was obtained in the same manner as in Example 1, except that the vapor-deposited layers were such that the aluminum metal layer had a thickness of 25 nm and the aluminum oxide layer had a thickness of 5 nm.

(Example 3)
A gas-barrier aluminum vapor-deposited film was obtained in the same manner as in Example 1, except that the vapor-deposited layers were such that the aluminum metal layer had a thickness of 80 nm and the aluminum oxide layer had a thickness of 20 nm.

(Example 4)
A gas barrier aluminum deposited film was obtained in the same manner as in Example 1, except that the gas barrier resin layer thickness was adjusted to 0.1 μm.

(Comparative example 1)
A gas-barrier aluminum vapor-deposited film was obtained in the same manner as in Example 1, except that the thickness of the aluminum metal layer alone was adjusted to 50 nm without supplying oxygen to the vapor-deposited layer.

(Comparative example 2)
A gas-barrier aluminum vapor-deposited film was obtained in the same manner as in Example 1, except that metal aluminum was evaporated while oxygen gas was supplied to the entire surface of the vapor-deposited layer so that the film thickness of the aluminum oxide layer alone was 10 nm.

(Comparative Example 3)
A vapor-deposited gas-barrier aluminum film was obtained in the same manner as in Example 1, except that the film thickness of the gas-barrier resin layer was 5 μm.

(Comparative Example 4)
A vapor-deposited gas barrier aluminum film was obtained in the same manner as in Example 1, except that the film thickness of the gas barrier resin layer was adjusted to 0.05 μm.

(Comparative Example 5)
A vapor-deposited gas barrier aluminum film was obtained in the same manner as in Example 1, except that an aqueous solution having the following composition was applied by gravure coating and dried to form a gas barrier resin layer having a thickness of 0.3 μm. The mixing ratio (% by weight) of (solution A)/(solution B) having the following composition was set to 20/80.

(Aqueous solution for gas barrier resin layer formation)
(Liquid A): Acrylonitrile (AN), 2-hydroxyethyl methacrylate (HEMA), and methyl methacrylate (MMA) monomers are blended in proportions of 20/50/30% by weight, respectively, and propyl acetate, propylene glycol monomethyl ether, Liquid A was prepared by dissolving in a mixed solvent of n-propyl alcohol (solid content: 30% by weight).

(B solution): Xylylene diisocyanate and methyl ethyl ketone were blended at 10/90 and stirred to prepare B solution.

Table 1 shows the structure and characteristics of the films prepared in Examples and Comparative Examples.

(Reference example 1)
Using a 12 μm-thick ethylene-vinyl alcohol copolymer film (“EVAL (registered trademark)” film VMXL manufactured by Kuraray Co., Ltd.), an aluminum metal layer and an aluminum oxide layer were vapor-deposited under the same conditions as in Example 1. A layer without a gas barrier resin layer was prepared. The water vapor transmission rate was insufficient at 2.0 g/m ² ·24 hr.

(Reference example 2)
A 6 μm-thick aluminum foil was used as the gas barrier film, a 40 μm-thick linear low-density polyethylene film was used as the sealant film in the same manner as in Example 1, and a 15 μm-thick biaxially oriented nylon film was used as the plastic film. It was laminated to form a laminated film. The puncture strength was 9N, which was smaller than that of the laminated films of the examples of the present invention.

As is clear from the results of each of the above Examples, the gas-barrier aluminum vapor-deposited film of the present invention is excellent in oxygen barrier performance and water vapor barrier performance, and can maintain these gas barrier performances even when stretched or bent. there were.

On the other hand, in Comparative Example 1, the adhesion between the aluminum layer and the gas barrier resin layer is low, resulting in poor lamination strength. In Comparative Example 2, there is no aluminum layer, resulting in poor infrared reflectance. Peeling occurred due to cohesive failure within the gas barrier resin layer, and the adhesion strength between the vapor deposition layer and the gas barrier resin layer was low. In Comparative Example 4, the gas barrier resin layer was thin and poor in barrier properties. In Comparative Example 5, the gas barrier resin layer was not a vinyl alcohol resin and an organosilicon compound having an alkoxy group. Performance and water vapor barrier property decreased.

Since the gas-barrier aluminum vapor-deposited film of the present invention has excellent oxygen barrier performance and water vapor barrier performance, it is also useful as a vacuum insulation exterior material that requires high gas barrier performance.

Claims (2)

Formed on at least one surface of the substrate film surface is a deposited layer whose composition changes continuously from an aluminum metal layer with a thickness of 25 nm or more and 125 nm or less to an aluminum oxide layer with a thickness of 5 nm or more and 25 nm or less, and furthermore A gas barrier resin layer having a thickness of 0.1 to 4 μm is laminated on the substrate, and the gas barrier resin layer is composed of a gas barrier composition obtained by polycondensation of a vinyl alcohol resin and an organic silicon compound having an alkoxy group. The adhesion strength between the layer and the gas barrier resin layer is 3.0 N/15 mm or more, the water vapor permeability after 5% tension is 0.1 g/m ² 24 hr or less, and the oxygen permeability is 0.1 cc/m ² · 24 hr · atm or less, a water vapor transmission rate after a bending fatigue test is 0.5 g / m ² · 24 hr or less, an oxygen transmission rate is 0.2 cc / m ² · 24 hr · atm or less, infrared A gas-barrier aluminum deposited film characterized by having an infrared reflectance of 60% or more as measured with a spectrophotometer at a relative reflection angle of 12 degrees of a reflector . A laminated film comprising a sealant film, a gas barrier film and a plastic film laminated in this order, wherein the gas barrier film comprises the gas barrier aluminum deposited film according to claim 1 .