JP6876265B2 - Gas barrier film - Google Patents

Description

The present invention relates to a gas barrier film.

In the packaging materials used for packaging foods, pharmaceuticals, etc., ingress of water vapor, oxygen, and other gases that alter the contents in order to suppress deterioration and decay of the contents and maintain their functions and properties. (Gas barrier property) is required. Therefore, conventionally, those packaging materials having a gas barrier layer have been used.
The gas barrier layer is generally provided on a base material such as a film or paper by a sputtering method, a vapor deposition method, a wet coating method, a printing method, or the like.
The gas barrier layer includes a metal foil made of a metal such as aluminum, a metal vapor deposition film, a metal oxide vapor deposition film, a water-soluble polymer such as polyvinyl alcohol or an ethylene-vinyl alcohol copolymer, a gas barrier polyurethane resin, or poly. A resin film made of a resin such as vinylidene chloride, a composite film of the water-soluble polymer and an inorganic layered mineral, and the like are used (see, for example, Patent Documents 1 to 6).

However, although the resin film made of polyvinylidene chloride exhibits good gas barrier properties that are not humidity-dependent, it contains chlorine and may be a source of harmful substances such as dioxins during disposal. , There is a tendency to dislike using it as a packaging material.
Resin membranes made of water-soluble polymers such as non-chlorine polyvinyl alcohol and ethylene-vinyl alcohol copolymer show high gas barrier properties in a low humidity atmosphere, but the gas barrier properties are humidity-dependent, and as the humidity rises. There is a drawback that the gas barrier property is greatly reduced.
A resin film made of a resin other than polyvinylidene chloride and a water-soluble polymer has inferior gas barrier properties as compared with a resin film made of polyvinylidene chloride or a resin film made of a water-soluble polymer in a low humidity atmosphere. There is.
The composite film of the water-soluble polymer and the inorganic layered mineral has improved humidity dependence as compared with the resin film made of the water-soluble polymer, but the effect is not sufficient and the adhesion to the substrate is lowered. There is a problem to do.
Further, although these resin films and composite films exhibit a barrier property against oxygen gas, the barrier property against water vapor is not sufficient.
Metal leafs and metal vapor deposition films exhibit excellent barrier properties against both oxygen and water vapor. However, since it is opaque, there is a problem that the contents cannot be confirmed.
A vapor-deposited film of a metal oxide such as silicon oxide exhibits an excellent barrier property against both oxygen and water vapor, and is transparent. However, since it is inferior in elasticity, there is a problem that cracks occur at an elongation of several percent and the gas barrier property is lowered.

To solve the above problems, a technique for improving gas barrier properties by providing a gas barrier vapor deposition layer containing an inorganic compound and a gas barrier coating layer on a resin base material (Patent Document 7), on an inorganic thin film made of silicon oxide. A technique for protecting an inorganic thin film by providing a top coat layer on the surface (Patent Document 8), a packaging material in which a transparent primer layer, a thin-film deposition film layer made of an inorganic oxide, and a gas barrier composite film are sequentially laminated on one side of a polypropylene base material. A technique for improving the gas barrier property of the above (for example, Patent Document 9) has been proposed.
However, even with the gas barrier film using the above technique, there is room for further improvement in the gas barrier property and the gas barrier property after the stretching treatment.

Japanese Unexamined Patent Publication No. 2001-287294 Japanese Unexamined Patent Publication No. 11-165369 Japanese Unexamined Patent Publication No. 6-93133 Japanese Unexamined Patent Publication No. 9-150484 Japanese Patent No. 3764109 Japanese Patent No. 4524463 International Publication No. 2004/048081 Japanese Patent No. 4398265 Japanese Unexamined Patent Publication No. 2000-259494

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas barrier film having excellent gas barrier properties and suppressing deterioration of gas barrier properties due to mechanical factors such as stretching.

The present invention has the following aspects.
<1> A resin substrate, a vapor-deposited film layer, and a coating layer provided on the opposite side of the vapor-deposited film layer from the resin substrate are provided.
The coating layer is a layer formed from a coating agent, and the coating agent contains an aqueous polyurethane resin (A) containing an acid group-containing polyurethane resin and a polyamine compound, and a water-soluble polymer (B). The mass ratio of the water-based polyurethane resin (A) to the water-soluble polymer (B) in terms of solid content is 85/15 to 10/90.
A gas barrier film having a coating layer having a thickness of 100 nm or more.
<2> The gas barrier film according to <1>, wherein the resin base material contains either one or both of a polyester resin and a polyamide resin.
<3> A base layer is further provided between the resin base material and the thin-film deposition film layer.
The underlayer is a polyol, an organosilicon compound and / or a hydrolyzed polycondensate of the organosilicon compound, a polyurethane resin, a reaction product of the polyol and the organosilicon compound, and the polyol, the organosilicon compound and isocyanate. The gas barrier film according to <1> or <2>, which comprises at least one organopolymer material selected from the group consisting of reaction products with compounds.
<4> The gas barrier film according to any one of <1> to <3>, wherein the coating agent further contains an inorganic layered mineral (C).
<5> The gas barrier film according to <4>, wherein the inorganic layered mineral (C) contains a water-swellable synthetic mica.
<6> The gas barrier film according to any one of <1> to <5>, wherein the coating agent further contains a silane coupling agent (D).
<7> The gas barrier film according to any one of <1> to <6>, wherein the coating layer has a thickness of 100 nm to 1400 nm.

According to the present invention, it is possible to provide a gas barrier film which is excellent in gas barrier property and in which deterioration of gas barrier property due to mechanical factors such as stretching is suppressed.

It is sectional drawing which shows typically the 1st Embodiment of the gas barrier film of this invention. It is sectional drawing which shows typically the 2nd Embodiment of the gas barrier film of this invention.

Hereinafter, the gas barrier film of the present invention will be described with reference to the accompanying drawings, showing embodiments. It should be noted that the embodiments shown below are specifically described in order to better understand the gist of the invention, and do not limit the present invention unless otherwise specified.

<< First Embodiment >>
FIG. 1 is a cross-sectional view schematically showing a first embodiment of the gas barrier film of the present invention.
The gas barrier film 10 of the present embodiment includes a resin base material 1, a vapor-deposited film layer 2, and a coating layer 3 provided on the side of the vapor-deposited film layer 2 opposite to the resin base material side. That is, the resin base material 1, the vapor-deposited film layer 2, and the coating layer 3 are laminated in this order.

<Resin base material>
Examples of the resin constituting the resin base material 1 include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polystyrene; polyamides such as 66-nylon; polycarbonate, polyacrylonitrile, and Examples include engineering plastics such as polyimide. A resin film obtained by processing one of these resins alone or by blending two or more of them into a film can be used as the resin base material 1. The resin film may be stretched or unstretched. As the resin film, a biaxially stretched film stretched in the biaxial direction is preferable.
The resin base material 1 may be composed of one resin layer (for example, a resin film), or may be one in which two or more resin layers (for example, a resin film) are laminated.

A preferable example of the resin base material 1 is a resin base material having a biaxially stretched polypropylene film. The biaxially stretched polypropylene film has excellent water vapor barrier properties. Therefore, the gas barrier film using this resin base material has more excellent water vapor barrier property.
Another preferred example of the resin base material 1 is a resin base material containing either or both of a polyester-based resin and a polyamide-based resin. This resin base material has high mechanical strength and good dimensional stability. Therefore, in the gas barrier film using this resin base material, the decrease in gas barrier property due to mechanical factors such as stretching is further suppressed.
As the resin base material 1, a resin base material having either or both of a biaxially stretched polyester resin film and a biaxially stretched polyamide resin film is particularly preferable.

The resin base material 1 may contain additives such as fillers, antistatic agents, plasticizers, lubricants, and antioxidants. Any one of these additives may be used alone, or two or more thereof may be used in combination.
The thickness of the resin base material 1 is not particularly limited, and may be, for example, 3 to 200 μm or 6 to 30 μm. The thickness of the resin base material 1 may be adjusted according to the application or required properties.
The surface of the resin base material 1 may be subjected to at least one treatment selected from the group consisting of chemical treatment, solvent treatment, corona treatment, plasma treatment and ozone treatment.

<Thin-film deposition film layer>
The thin-film film layer 2 is typically made of a metal oxide. Examples of the metal oxide include aluminum oxide and silicon oxide. The thin-film film layer 2 may be a layer made of a single metal oxide, or may be a layer made of a combination of two or more kinds of metal oxides.

The thin-film film layer 2 _{preferably contains silicon oxide [SiO x} (x is about 2)]. When the vapor-deposited film layer 2 contains silicon oxide, it is possible to produce a gas-barrier film having particularly excellent water vapor barrier properties, high flexibility and transparency.
The content of silicon oxide in the thin-film film layer 2 may be, for example, 60% by mass or more, 70% by mass or more, or 100% by mass with respect to the total mass of the thin-film film layer 2. May be good.

The thickness of the thin-film film layer 2 may be, for example, 5 to 100 nm or 10 to 80 nm.

The thin-film film layer 2 can be formed on the resin base material 1 by a normal vacuum vapor deposition method. As the heating means of the vacuum vapor deposition method, it is preferable to use any one of an electron beam heating method, a resistance heating method, and an induction heating method. In order to improve the adhesion between the thin-film film layer 2 and the resin base material 1 and the denseness of the thin-film film layer 2, it is also possible to carry out vapor deposition using a plasma assist method or an ion beam assist method.

<Coating layer>
The coating layer 3 is a layer formed from a specific coating agent.
Since the thin-film film layer 2 contains a metal oxide, its flexibility is low. Since the highly flexible coating layer 3 is provided on the opposite side of the vapor-deposited film layer 2 from the resin base material 1, the thin-film film layer 2 is damaged by mechanical factors such as stretching of the gas barrier film. Deterioration of gas barrier property can be suppressed. Therefore, the post-processing suitability of the gas barrier film 10 is high, and the gas barrier property is unlikely to deteriorate when post-processing such as bag making in a packaging bag is performed.

The coating agent contains an aqueous polyurethane resin (A) and a water-soluble polymer (B).
The coating agent preferably further contains an inorganic layered mineral (C).
The coating agent preferably further contains a silane coupling agent (D).
The coating agent is, if necessary, an aqueous polyurethane resin (A), a water-soluble polymer (B), an inorganic layered mineral (C), and a silane coupling agent as long as the gas barrier property and the strength as a laminated film are not impaired. Other components other than (D) may be further contained.

"Aqueous polyurethane resin (A)"
The aqueous polyurethane resin (A) contains an acid group-containing polyurethane resin and a polyamine compound.
The aqueous polyurethane resin (A) is used to impart flexibility and gas barrier properties, particularly oxygen barrier properties, to the coating layer 3. In the aqueous polyurethane resin (A), the gas barrier property is exhibited by binding the acid group of the acid group-containing polyurethane resin and the polyamine compound as a cross-linking agent.
The bond between the acid group of the acid group-containing polyurethane resin and the polyamine compound may be an ionic bond (for example, an ionic bond between a carboxyl group and a tertiary amino group) or a covalent bond (for example, an amide bond). It may be.

Since the acid group-containing polyurethane resin constituting the aqueous polyurethane resin (A) has an acid group, it has anionic and self-emulsifying properties, and is also referred to as an anionic self-emulsifying polyurethane resin.
The acid group of the acid group-containing polyurethane resin can be bonded to the amino group (primary amino group, secondary amino group, tertiary amino group, etc.) of the polyamine compound constituting the aqueous polyurethane resin (A).
Examples of the acid group include a carboxyl group and a sulfonic acid group. The acid group can usually be neutralized by a neutralizing agent (base), and may form a salt with the base.
The acid group may be located at the end of the acid group-containing polyurethane resin or in the side chain, but is preferably located at least in the side chain.

The acid value of the acid group-containing polyurethane resin can be selected within the range in which the acid group-containing polyurethane resin is water-dispersible, but is usually 5 to 100 mgKOH / g, preferably 10 to 70 mgKOH / g. More preferably, it is 15 to 60 mgKOH / g. If the acid value of the acid group-containing polyurethane resin is less than the lower limit of the above range, the water dispersibility of the acid group-containing polyurethane resin becomes insufficient, and the uniform dispersibility between the aqueous polyurethane resin and other materials and the dispersion of the coating agent It may lead to a decrease in stability. If the acid value of the acid group-containing polyurethane resin exceeds the upper limit of the above range, the water resistance and gas barrier property of the coating layer 3 may be deteriorated. When the acid value of the acid group-containing polyurethane resin is within the above range, it is possible to avoid a decrease in dispersion stability and a decrease in water resistance and gas barrier property.
The acid value of the acid group-containing polyurethane resin is measured by a method according to JIS K 0070.

From the viewpoint of gas barrier properties, the total of the urethane group concentration and the urea group (urea group) concentration of the acid group-containing polyurethane resin is preferably 15% by mass or more, and more preferably 20 to 60% by mass. If the total of the urethane group concentration and the urea group concentration is less than the above lower limit value, the gas barrier property of the coating layer 3 may be insufficient. If the total of the urethane group concentration and the urea group concentration exceeds the upper limit of the above range, the coating layer 3 may become rigid and brittle.
The urethane group concentration means the ratio of the molecular weight (59 g / equivalent) of the urethane group to the molecular weight of the repeating structural unit of the polyurethane resin. The urea group concentration means the ratio of the molecular weight of the urea group (primary amino group (amino group): 58 g / equivalent, secondary amino group (imino group): 57 g / equivalent) to the molecular weight of the repeating constituent unit of the polyurethane resin. To do. When a mixture of two or more kinds is used as the acid group-containing polyurethane resin, the urethane group concentration and the urea group concentration can be calculated based on the preparation base of the reaction component, that is, the usage ratio of each component.

The acid group-containing polyurethane resin usually has at least a rigid unit (a unit composed of a hydrocarbon ring) and a short chain unit (for example, a unit composed of a hydrocarbon chain). That is, the constituent unit of the acid group-containing polyurethane resin is usually derived from a polyisocyanate component, a polyhydroxyic acid component, a polyol component or a chain extender component (particularly, at least a polyisocyanate component), and is a hydrocarbon ring (aromatic and). Contains at least one of the non-aromatic hydrocarbon rings).
The ratio of the unit composed of the hydrocarbon ring to the constituent unit of the acid group-containing polyurethane resin is usually 10 to 70% by mass, preferably 15 to 65% by mass, based on the total of all the constituent units. It is preferably 20 to 60% by mass. If the ratio of the unit composed of the hydrocarbon ring is less than the lower limit of the above range, the gas barrier property of the coating layer 3 may be insufficient. If the proportion of units composed of hydrocarbon rings exceeds the upper limit of the above range, the coating layer 3 may become rigid and brittle.

The number average molecular weight of the acid group-containing polyurethane resin can be appropriately selected, but is preferably 800 to 1,000,000, more preferably 800 to 200,000, and more preferably 800 to 100,000. Is even more preferable. If the number average molecular weight of the acid group-containing polyurethane resin exceeds the upper limit of the above range, the viscosity of the coating agent increases, which is not preferable. If the number average molecular weight of the acid group-containing polyurethane resin is less than the lower limit of the above range, the gas barrier property of the coating layer 3 may be insufficient.
The number average molecular weight of the acid group-containing polyurethane resin is a standard polystyrene-equivalent value measured by gel permeation chromatography (GPC).

The acid group-containing polyurethane resin may be crystalline in order to enhance the gas barrier property.
The glass transition temperature of the acid group-containing polyurethane resin is preferably 100 ° C. or higher, more preferably 110 ° C. or higher, and even more preferably 120 ° C. or higher. If the glass transition temperature of the acid group-containing polyurethane resin is less than 100 ° C., the gas barrier property of the coating layer 3 may be insufficient.
The glass transition temperature of the acid group-containing polyurethane resin is typically 200 ° C. or lower, further 180 ° C. or lower, and further 150 ° C. or lower. It is substantially unlikely that the glass transition temperature of the acid group-containing polyurethane resin satisfying the preferable range of each of the above items will be higher than the above upper limit value.
Therefore, the glass transition temperature of the acid group-containing polyurethane resin is preferably 100 to 200 ° C., more preferably 110 to 180 ° C., and even more preferably 120 to 150 ° C.
The glass transition temperature of the acid group-containing polyurethane resin is measured by differential scanning calorimetry (DSC).

The polyamine compound constituting the aqueous polyurethane resin (A) is a compound having two or more basic nitrogen atoms.
The basic nitrogen atom is a nitrogen atom that can be bonded to an acid group of an acid group-containing polyurethane resin. For example, a nitrogen atom in an amino group such as a primary amino group, a secondary amino group, or a tertiary amino group is used. Can be mentioned.
The polyamine compound is not particularly limited as long as it can bond with the acid group of the acid group-containing polyurethane resin and improve the gas barrier property, and various compounds having two or more basic nitrogen atoms can be used. it can.
As the polyamine compound, a polyamine compound having two or more at least one amino group selected from the group consisting of a primary amino group, a secondary amino group and a tertiary amino group is preferable.

Specific examples of the polyamine compound include alkylenediamines, polyalkylene polyamines, and silicon compounds having a plurality of basic nitrogen atoms. Examples of alkylenediamines include alkylenediamines having 2 to 10 carbon atoms such as ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butanediamine, and 1,6-hexamethylenediamine. Be done. Examples of polyalkylene polyamines include tetraalkylene polyamines. Examples of the silicon compound having a plurality of basic nitrogen atoms (including nitrogen atoms such as amino groups) include 2- [N- (2-aminoethyl) amino] ethyltrimethoxysilane and 3- [N- (2-). Examples thereof include a silane coupling agent having a plurality of basic nitrogen atoms such as aminoethyl) amino] propyltriethoxysilane.
The silane coupling agent corresponding to the polyamine compound shall not correspond to the silane coupling agent (D).

The amine value of the polyamine compound is preferably 100 to 1900 mgKOH / g, more preferably 150 to 1900 mgKOH / g, further preferably 200 to 1900 mgKOH / g, particularly preferably 200 to 1700 mgKOH / g, and most preferably 300 to 1500 mgKOH / g. .. When the amine value of the polyamine compound is at least the lower limit of the above range, the coating layer 3 has excellent gas barrier properties. When the amine value of the polyamine compound is not more than the upper limit of the above range, the aqueous polyurethane resin (A) is excellent in water dispersion stability.
The amine value of a polyamine compound is measured by the following method.

[Measuring method of amine value]
Weigh 0.5 to 2 g of the sample (sample amount Sg). Add 30 g of ethanol to the precisely weighed sample and dissolve. Bromophenol blue is added to the obtained solution as an indicator, and titration is performed with a 0.2 mol / L ethanolic hydrochloric acid solution (titer f). With the point where the color of the solution changes from green to yellow as the end point, the amine titer is calculated using the following formula 1 using the titration amount (AmL) at this time.
Calculation formula 1: Amine value = A × f × 0.2 × 56.108 / S [mgKOH / g]

In the aqueous polyurethane resin (A), the content of the polyamine compound is such that the molar ratio (acid group / basic nitrogen atom) of the acid group of the acid group-containing polyurethane resin to the basic nitrogen atom of the polyamine compound is 10/1 to 1 to 1. The amount to be 0.1 / 1 is preferable, and the amount to be 5/1 to 0.2 / 1 is more preferable. When the acid group / basic nitrogen atom is in the above range, the cross-linking reaction between the acid group of the acid group-containing polyurethane and the polyamine compound occurs appropriately, and the coating layer 3 exhibits excellent oxygen barrier properties.

The aqueous polyurethane resin (A) is usually used in the form of being dispersed in an aqueous medium (aqueous dispersion).
Aqueous media include water, water-soluble or hydrophilic organic solvents, or mixtures thereof. Examples of the water-soluble or hydrophilic organic solvent include alcohols such as methanol, ethanol and isopropanol; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; cellosolves; carbitols; nitriles such as acetonitrile and the like. Can be mentioned.
As the aqueous medium, water or one containing water as a main component is preferable. The content of water in the aqueous medium is preferably 70% by mass or more, more preferably 80% by mass or more.
The aqueous medium may or may not contain a neutralizing agent (base) that neutralizes the acid group of the acid group-containing polyurethane resin. Usually contains a neutralizing agent.

In the aqueous dispersion of the aqueous polyurethane resin (A), the average particle size of the dispersed particles (polyurethane resin particles) is not particularly limited, and is preferably 20 nm to 500 nm, more preferably 25 nm to 300 nm, and further preferably. It is 30 nm to 200 nm. When the average particle size of the dispersed particles exceeds the upper limit of the above range, the uniform dispersibility between the dispersed particles and other materials and the dispersion stability of the coating agent are lowered, and the gas barrier of the coating layer 3 formed from the coating agent. There is a risk of insufficient sex. If the average particle size of the dispersed particles is less than the lower limit of the above range, the effect of further improving the dispersion stability of the coating agent and the gas barrier property of the coating layer 3 formed from the coating agent cannot be expected. Also, it is practically difficult to obtain such a dispersion.
The average particle size is a value measured by a concentrated particle size analyzer (FPAR-10 manufactured by Otsuka Electronics Co., Ltd.) with a solid content concentration of 0.03 to 0.3% by mass (diluted with water). ..

As the aqueous polyurethane resin (A), a commercially available one may be used, or one manufactured by a known production method may be used.
The method for producing the aqueous polyurethane resin (A) is not particularly limited, and ordinary polyurethane resin aqueous techniques such as an acetone method and a prepolymer method are used. In the urethanization reaction, a urethanization catalyst such as an amine-based catalyst, a tin-based catalyst, or a lead-based catalyst may be used, if necessary.
For example, in an inert organic solvent such as ketones such as acetone, ethers such as tetrahydrofuran, and nitriles such as acetonitrile, a polyisocyanate compound, a polyhydroxyic acid, and, if necessary, a polyol component and a chain extender component. An acid group-containing polyurethane resin can be prepared by reacting with at least one of them. More specifically, a pre-isocyanate compound having an isocyanate group at the terminal is reacted by reacting a polyisocyanate compound, a polyhydroxyic acid, and a polyol component in an inert organic solvent (particularly, a hydrophilic or water-soluble organic solvent). A polymer is produced, neutralized with a neutralizing agent, dissolved or dispersed in an aqueous medium, and then a chain extender component is added and reacted to remove an organic solvent, whereby an acid group-containing polyurethane resin is aqueously dispersed. Can prepare the body.
The aqueous polyurethane resin (A) in the form of an aqueous dispersion can be prepared by adding a polyamine compound to the aqueous dispersion of the acid group-containing polyurethane resin thus obtained and heating as necessary. When heating, the heating temperature is preferably 30 to 60 ° C.

"Water-soluble polymer (B)"
"Water-soluble polymer" refers to a polymer that is soluble in water. The term "dissolution" as used herein refers to a state in which a polymer as a solute is dispersed in water as a solvent at the molecular chain level to form a uniform system. More specifically, it refers to a state in which the intermolecular force with the water molecule is stronger than the intermolecular force between the molecular chains of the polymer chain, the entanglement of the polymer chains is disentangled, and the polymer chains are uniformly dispersed in water.
The water-soluble polymer (B) is used in particular to improve the flexibility of the coating layer 3 and suppress the deterioration of the gas barrier property due to post-processing.

Specific examples of the water-soluble polymer (B) include polyvinyl alcohol resins such as polyvinyl alcohol-based polymers and derivatives thereof; polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid or esters thereof, salts and copolymers thereof. , Vinyl-based polymers such as polyhydroxyethyl methacrylate and copolymers thereof; cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose; starches such as oxidized starch, etherified starch and dextrin; and polar groups such as sulfoisophthalic acid. Examples thereof include copolymerized polyesters having an acid component; water-soluble urethane-based polymers, and functional group-modified polymers in which functional groups (carboxyl groups, etc.) of these various polymers are modified. Examples of the derivative of the polyvinyl alcohol-based polymer include a graft polymer in which a monomer is graft-polymerized on the side chain of polyvinyl alcohol.
The water-soluble polymer (B) preferably has a degree of polymerization of 200 or more in consideration of the film cohesive strength.
The water-soluble polymer (B) contained in the coating agent may be one kind or two or more kinds.

The water-soluble polymer (B) contains at least one polyvinyl alcohol resin selected from the group consisting of polyvinyl alcohol-based polymers and derivatives thereof from the viewpoint of achieving both gas barrier properties and flexibility of the coating layer 3. It is preferable, and it is particularly preferable to contain a polyvinyl alcohol resin having a saponification degree of 95% or more and a polymerization degree of 300 or more. The degree of polymerization of the polyvinyl alcohol resin is preferably 300 to 2400, particularly preferably 450 to 2000.
The higher the degree of saponification and the degree of polymerization of the polyvinyl alcohol resin, the lower the hygroscopic swelling property and the higher the gas barrier property. If the degree of saponification of the polyvinyl alcohol resin is less than 95%, sufficient gas barrier properties may not be obtained. If the degree of polymerization of the polyvinyl alcohol resin is less than 300, the gas barrier property and the film cohesive strength may be lowered. If the degree of polymerization of the polyvinyl alcohol resin exceeds 2000, the viscosity of the coating agent increases, it is difficult to uniformly mix the polyvinyl alcohol resin with other components, and there is a risk of causing problems such as a decrease in gas barrier property and adhesion strength.

"Inorganic layered mineral (C)"
The "inorganic layered mineral" refers to an inorganic compound in which ultrathin unit crystal layers are overlapped to form one layered particle. The inorganic layered mineral (C) is used for the purpose of imparting further oxygen barrier property and water vapor barrier property to the coating layer 3.
As the inorganic layered mineral (C), a compound that swells and / or cleaves in water is preferable, and a clay compound having swelling property in water is particularly preferable. More specifically, the inorganic layered mineral (C) is preferably a clay compound having the property of coordinating water between ultrathin unit crystal layers and absorbing and / or swelling. In general, such clay compounds have ^{a layer in which Si 4+} is coordinated with respect to O ^2- to form a tetrahedral structure, and Al ³⁺ , Mg ²⁺ , Fe ²⁺ , Fe ^{3+ and the} like are O ^2- and OH ⁻ . It is a compound in which layers that are coordinated with each other to form an octahedral structure are bonded in a one-to-one or two-to-one manner and are stacked to form a layered structure. This clay compound may be a natural compound or a synthesized compound.

Typical examples of the inorganic layered mineral (C) include hydrous silicates such as phyllosilicate minerals, and for example, kaolinite clay minerals such as halloysite, kaolinite, enderite, dikite, and nacrite; anti Anti-Golite clay minerals such as golite and chrysotile; Smectite clay minerals such as montmorillonite, biderite, nontronite, saponite, hectolite, soconite and stebunsite; vermiculite clay minerals such as vermiculite; white mica, gold mica, Mica or mica clay minerals such as margarite, tetrasilic mica, teniolite: and the like. These inorganic layered minerals (C) are used alone or in combination of two or more.
Among these inorganic layered minerals (C), smectite group clay minerals such as montmorillonite and mica group clay minerals such as water-swellable mica are preferable.

The average particle size of the inorganic layered mineral (C) is preferably 10 μm or less. When the average particle size is not more than the upper limit value, the inorganic layered mineral (C) is likely to be uniformly aligned in the coating layer 3, and the gas barrier property and the film cohesive strength are high. The average particle size of the inorganic layered mineral (C) is measured by a laser diffraction type particle size distribution meter.
The thickness of the inorganic layered mineral (C) is preferably 500 nm or less. When the thickness is not more than the upper limit value, the inorganic layered mineral (C) is likely to be uniformly aligned in the coating layer 3, and the gas barrier property and the film cohesive strength are high. The thickness of the inorganic layered mineral (C) is measured by an atomic force microscope (AFM).
Therefore, it is particularly preferable that the inorganic layered mineral (C) has an average particle size of 10 μm or less and a thickness of 500 nm or less.

The inorganic layered mineral (C) preferably contains at least a water-swellable synthetic mica, and particularly preferably contains a water-swellable synthetic mica having an average particle size of 1 to 10 μm and a thickness of 10 to 100 nm. The water-swellable synthetic mica has a high affinity for the aqueous polyurethane resin (A) and the water-soluble polymer (B), and has less impurities than the natural mica. Therefore, when water-swellable synthetic mica is used as the inorganic layered mineral (C), it is unlikely that the gas barrier property and the film cohesive force due to impurities are lowered. Further, since the water-swellable synthetic mica has a fluorine atom in the crystal structure, it also contributes to suppressing the humidity dependence of the gas barrier property of the coating layer 3 formed from the coating agent to be low. In addition, since the water-swellable synthetic mica has a higher aspect ratio than other water-swellable inorganic layered minerals, the maze effect works more effectively, and the coating layer 3 formed from the coating agent. Contributes to the development of particularly high gas barrier properties.
The content of the water-swellable synthetic mica may be, for example, 50% by mass or more, 70% by mass or more, or 100% by mass with respect to the total mass of the inorganic layered mineral (C). ..

"Silane coupling agent (D)"
As the silane coupling agent (D), a commonly used one can be used, and examples thereof include a compound having an alkoxy group bonded to a silicon atom and an organic reaction group.
The alkoxy group of the silane coupling agent (D) is hydrolyzed to generate a silanol group, which exerts an interaction effect such as reaction with an inorganic compound and adsorption, and has a cohesive strength of the coating layer 3 formed from the coating agent. Contribute to improvement.
In particular, when the coating agent contains both the inorganic layered mineral (C) and the silane coupling agent (D), the inorganic layered mineral (C) and the silane coupling agent (D) interact with each other to form the coating agent. The effect of improving the cohesive strength of the coating layer 3 is excellent.

Examples of the silane coupling agent (D) include _{compounds represented by RSiX 3} (where R is an organic reactive group and X is an alkoxy group).
Examples of the organic reactive group include those having an amino group, a (meth) acrylic group, an epoxy group, a vinyl group, a mercapto group, an isocyanate group, an isocyanurate group and the like. The (meth) acrylic group represents both an acrylic group and a methacrylic group.
Examples of the alkoxy group include a methoxy group and an ethoxy group.

Examples of the silane coupling agent (D) include vinyltrimethoxysilane and vinyltriethoxysilane as the silane coupling agent having a vinyl group. As a silane coupling agent having an epoxy group, 2 (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyl Examples thereof include methyldimethoxysilane and 3-glycidoxypropylethyldiethoxysilane. Examples of the silane coupling agent having an amino group include 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane. Examples of the silane coupling agent having a mercapto group include 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxysilane. Examples of the silane coupling agent having a (meth) acrylic group include 3-acryloxypropyltrimethoxysilane. Examples of the silane coupling agent having an isocyanate group include 3-isocyanatepropyltriethoxysilane. Examples of the silane coupling agent having an isocyanurate group include tris- (trimethoxysilylpropyl) isocyanurate. Any one of these silane coupling agents may be used alone, or two or more thereof may be used in combination.

As the silane coupling agent (D), one in which the organic reactive group has reactivity with the components in the coating agent is preferably used.
The silane coupling agent (D) preferably has an epoxy group. Since the epoxy group has good reactivity with the hydroxyl groups of the aqueous polyurethane resin (A) and the water-soluble polymer (B), the gas barrier property of the coating layer 3 can be further improved.

"Other ingredients"
Examples of other components include additives such as antioxidants, weathering agents, heat stabilizers, lubricants, crystal nucleating agents, ultraviolet absorbers, plasticizers, antistatic agents, coloring agents, fillers, and surfactants. Be done.

"Content of each ingredient"
The mass ratio of the water-based polyurethane resin (A) and the water-soluble polymer (B) in the coating agent by solid content (water-based polyurethane resin (A) / water-soluble polymer (B)) is 85/15 to 10 /. It is 90, preferably 75/25 to 20/80, and particularly preferably 70/30 to 25/75.
When the water-based polyurethane resin (A) / water-soluble polymer (B) is within the above range, the coating agent can be applied evenly, and the coating layer 3 having excellent gas barrier properties and flexibility is formed. Can be done. If the content of the aqueous polyurethane resin (A) is higher than that of the aqueous polyurethane resin (A) / water-soluble polymer (B) being 85/15, unevenness may occur during coating. Unevenness during coating leads to deterioration of appearance and deterioration of gas barrier property. If the content of the aqueous polyurethane resin (A) is smaller than that of the aqueous polyurethane resin (A) / water-soluble polymer (B) being 10/90, the oxygen barrier property may be insufficient.

The content (solid content) of the inorganic layered mineral (C) in the coating agent is preferably 2% by mass or more and 25% by mass or less, and 3% by mass or more and 22% by mass, based on the total solid content in the coating agent. % Or less is more preferable, and 5% by mass or more and 20% by mass or less is particularly preferable. When the content of the inorganic layered mineral (C) is within the above range, the flexibility of the coating layer 3 can be maintained while improving the gas barrier property of the coating layer 3 formed from the coating agent. The deterioration of gas barrier property due to treatment is small.

The content (solid content) of the silane coupling agent (D) in the coating agent is preferably 0.5% by mass or more and 30% by mass or less with respect to the total solid content in the coating agent, and is 1% by mass. It is more preferably 25% by mass or less, and particularly preferably 3% by mass or more and 20% by mass or less. When the content of the silane coupling agent (D) is within the above range, the cohesive force and gas barrier property of the coating layer 3 can be sufficiently enhanced while maintaining the flexibility of the coating layer 3 formed from the coating agent. it can.

The total content (solid content) of the aqueous polyurethane resin (A), the water-soluble polymer (B), the inorganic layered mineral (C), and the silane coupling agent (D) in the coating agent is the total content (solid content) in the coating agent. It is preferably 85% by mass or more, more preferably 90% by mass or more, and particularly preferably 95% by mass or more with respect to the solid content. The upper limit of the total content is not particularly limited and may be 100% by mass.

The coating layer 3 can be formed by applying a coating agent to the surface of the vapor-deposited film layer 2 opposite to the resin base material 1 to form a coating film made of the coating agent, and drying the coating film. Details will be described later.

The thickness of the coating layer 3, that is, the thickness of the coating film made of the coating agent after drying is 100 nm or more, preferably 100 nm to 1400 nm, more preferably 100 nm to 1000 nm, and 120 nm to 800 nm. Is more preferable, and 150 nm to 600 nm is particularly preferable.
When the thickness of the coating layer 3 is at least the above lower limit value, sufficient gas barrier properties and stretch resistance can be easily obtained. When the thickness of the coating layer 3 is not more than the upper limit of the above range, it is suitable for post-processing such as stretching treatment, and the drying load and manufacturing cost can be suppressed.
When the thickness of the coating layer 3 is less than the lower limit, the oxygen gas barrier property of the gas barrier film is inferior. If the thickness of the coating layer 3 exceeds the upper limit of the above range, the deterioration of the gas barrier property due to the stretching treatment may increase. In addition, the cost required to increase the thickness also increases, and the drying and film forming properties are inferior.
The thickness of the coating layer 3 is measured by a scanning electron microscope (SEM).

<Manufacturing method of gas barrier film>
The gas barrier film 10 is, for example,
The step of forming the thin-film film layer 2 on one surface of the resin base material 1 and
A step of applying the coating agent to the surface of the vapor-deposited film layer 2 opposite to the resin base material 1 to form a coating film composed of the coating agent, and drying the coating film to form the coating film 3.
It can be manufactured by the manufacturing method having.

The method for forming the thin-film film layer 2 is as described above.
The coating agent forming the coating layer 3 is an aqueous polyurethane resin (A) and a water-soluble polymer (B), an inorganic layered mineral (C) if necessary, a silane coupling agent (D), other components, and further aqueous solution. It can be prepared by mixing a medium or the like. The mixing order of each component is not particularly limited. The silane coupling agent (D) may be mixed with other components, and is added to the mixture in which components other than the silane coupling agent (D) are mixed in advance immediately before coating on the resin base material 1. You may.

As a coating method, a known wet coating method can be used, and examples thereof include roll coating, gravure coating, reverse coating, die coating, screen printing, and spray coating.
As a method for drying the coating film composed of the coating agent, known drying methods such as hot air drying, hot roll drying, and infrared irradiation can be used. The drying temperature of the coating film can be, for example, 50 to 200 ° C. The drying time varies depending on the thickness of the coating film, the drying temperature, and the like, but can be, for example, 1 second to 5 minutes.

<Effect>
The gas barrier film 10 includes a resin base material 1, a vapor-deposited film layer 2, and a coating layer 3 provided on the opposite side of the vapor-deposited film layer 2 from the resin base material 1, and the coating layer is water-based. From a coating agent containing a polyurethane resin (A) and a water-soluble polymer (B), in which the mass ratio of the aqueous polyurethane resin (A) and the water-soluble polymer (B) in solid content is 85/15 to 10/90. Since it is a formed layer, it has excellent gas barrier properties, and the deterioration of gas barrier properties due to stretching isokinetic factors is small. Therefore, deterioration of the contents can be sufficiently suppressed when the packaging bag is used. Further, even if a force is applied to the packaging bag due to post-processing or long-distance transportation, the deterioration of the gas barrier property is small.

<< Second Embodiment >>
FIG. 2 is a cross-sectional view schematically showing a second embodiment of the gas barrier film of the present invention.
The gas barrier film 20 of the present embodiment has a resin base material 1, a vapor-deposited film layer 2, a base layer 4 provided between the resin base material 1 and the vapor-deposited film layer 2, and a resin group of the vapor-deposited film layer 2. It is provided with a coating layer 3 provided on the side opposite to the material 1 side. That is, the resin base material 1, the base layer 4, the vapor-deposited film layer 2, and the coating layer 3 are laminated in this order. In the present embodiment, the same reference numerals are given to the existing components, and detailed description thereof will be omitted.
The gas barrier film 20 is the same as the gas barrier film of the first embodiment except that the base layer 4 is further provided between the resin base material 1 and the vapor deposition film layer 2.

<Underground layer>
The base layer 4 is sometimes called a primer layer.
The base layer 4 is typically a layer containing an organic polymer material, and preferably contains the organic polymer material as a main component. The content of the organic polymer material in the base layer 4 may be, for example, 70% by mass or more, or 80% by mass or more, based on the total mass of the base layer 4.

Examples of the organic polymer material include a polyol, an organic silicon compound, a hydrolyzed polycondensate of the organic silicon compound, a polyurethane resin, a reaction product of the polyol and the organic silicon compound, and the polyol and the organic silicon compound. Examples thereof include reaction products with isocyanate compounds, polyethyleneimine and derivatives thereof, polyolefins, polyimides, melamine resins, phenol resins and the like. Any one of these organic polymer materials may be used alone, or two or more thereof may be used in combination.

Among the above, the organic polymer materials include polyols, organic silicon compounds and / and the organic substances in order to react with each other to form a strong covalent bond and exert strong adhesion to the vapor-deposited film layer 2. At least one selected from the group consisting of a hydrolyzed polycondensate of a silicon compound, a polyurethane resin, a reaction product of the polyol and the organic silicon compound, and a reaction product of the polyol, the organic silicon compound and an isocyanate compound. Organic polymer material (hereinafter, also referred to as organic polymer material (I)) is preferable.

The polyol is an organic polymer having two or more hydroxyl groups in the molecule.
Examples of the polyol include acrylic polyols, polyvinyl alcohols, polyester polyols, polyurethane polyols and the like. Any one of these may be used alone, or two or more thereof may be used in combination.
Acrylic polyol is a polymer having a structural unit based on an acrylic acid derivative monomer having a hydroxyl group. The acrylic polyol may be obtained by polymerizing an acrylic acid derivative monomer having a hydroxyl group, or may be obtained by copolymerizing an acrylic acid derivative monomer having a hydroxyl group with another monomer. .. Examples of the acrylic acid derivative monomer having a hydroxyl group include hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate and the like. Examples of the monomer copolymerized with the acrylic acid derivative monomer having a hydroxyl group include an acrylic acid derivative monomer having no hydroxyl group such as ethyl methacrylate and styrene.

The organic silicon compound is a compound having a silicon atom, a hydrolyzable group bonded to the silicon atom, and a non-hydrolyzable organic group bonded to the silicon atom. Hydrolysis of the organosilicon compound produces a hydrolyzate in which the hydrolyzable group is OH, and the hydrolyzates are polycondensed with each other to form a polycondensate.
Examples of the hydrolyzable group include an alkoxy group having 1 to 4 carbon atoms and an alkoxyalkyloxy group having 1 to 4 carbon atoms.
Examples of the non-hydrolytable organic group include an alkyl group, a vinyl group, a γ-chloropropyl group, a glycidoxypropyl group, a γ-methacryloxypropyl group, a γ-acryloxypropyl group, an aminopropyl group and an isocyanatepropyl group. And so on.
The organic silicon compound contains at least a functional group selected from an epoxy group, an amino group, and an isocyanate group as a non-hydrolytable organic group in that it has a reactivity with a hydroxyl group of a polyol or an isocyanate group of an isocyanate compound. It is preferable to have a group.

Examples of the organosilicon compound include a silane coupling agent. Examples of the silane coupling agent include vinyl trimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and γ-methacry. Examples thereof include loxypropylmethyldimethoxysilane, γ-isocyanuppropyltrimethoxysilane, γ-isocyanuppropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

Examples of the polyurethane resin include a reaction product (aqueous polyurethane resin) of a polyol and an isocyanate compound.
Examples of the polyol include the same as described above.
The isocyanate compound has an effect of enhancing the adhesion between the resin base material 1 and the vapor-deposited film layer 2 by the urethane bond generated by reacting with the polyol. That is, the isocyanate compound functions as a cross-linking agent or a curing agent. Examples of the isocyanate compound include isocyanates such as aromatic toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), aliphatic xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI) and isophorone diisocyanate (IPDI). Examples thereof include monomers having two or more groups, polymers thereof, and derivatives thereof. One type of the isocyanate compound may be used alone, or two or more types may be used in combination.
The ratio (mass ratio) of the polyol to the isocyanate compound (polyol / isocyanate compound) is preferably 1/3 to 20/1, more preferably 1/2 to 10/1.

In the reaction product of the polyol and the organosilicon compound, the ratio (mass ratio) of the polyol to the organosilicon compound (polypoly / organosilicon compound) is preferably 1/1 to 100/1. It is more preferably 2/1 to 50/1.
In the reaction product of the polyol, the organosilicon compound and the isocyanate compound, examples of the isocyanate compound include the same as described above.

The organic polymer material (I) may be used in combination with another organic polymer material. As the other organic polymer material, at least one selected from the group consisting of polyethyleneimine and its derivatives, polyolefins, polyimides, melamine resins and phenol resins is preferable.
The content of the organic polymer material (I) in the base layer 4 may be 70% by mass or more, 80% by mass or more, or 100% by mass with respect to the total mass of the base layer 4. You may.

The base layer 4 may further contain components other than the organic polymer material. Other components include silica particles such as organically modified colloidal silica; curing accelerators such as tertiary amines, imidazole derivatives, metal salts of carboxylic acids, quaternary ammonium salts, and quaternary phosphonium salts: phenolic compounds, sulfur compounds. Examples thereof include quaternary ammonium salts, antioxidants such as phosphite-based agents; leveling agents; flow modifiers; catalysts; cross-linking reaction accelerators; fillers and the like.

The thickness of the base layer 4 is not particularly limited and may be, for example, 0.005 to 5 μm. The thickness of the base layer 4 may be adjusted according to the required characteristics.
The thickness of the base layer 4 is measured by a scanning electron microscope (SEM).

A particularly preferable form of the gas barrier film 20 of the present embodiment is a gas barrier film in which the vapor-deposited film layer 2 contains silicon oxide and the base layer 4 contains an organic polymer material. The organic polymer material is preferably the organic polymer material (I).
In this form of gas barrier film, from the viewpoint of water vapor barrier property, it is preferable that the resin base material 1 is a resin base material having a biaxially stretched polypropylene film. From the viewpoint of mechanical strength and dimensional stability, the resin base material 1 is preferably a resin base material containing either or both of polyester resin and polyamide resin, and is preferably a biaxially stretched polyester resin film and biaxial. It is particularly preferable that the resin base material has either one or both of the stretched polyamide-based resin films.

<Manufacturing method of gas barrier film>
The gas barrier film 20 is, for example,
A base material containing an organic polymer material or a precursor thereof and a liquid medium is applied onto one surface of the resin base material 1 to form a coating film composed of the base material, and the coating film is dried to dry the base layer 4 And the process of forming
A step of forming the vapor-deposited film layer 2 on the surface of the base layer 4 opposite to the resin base material 1 and
A step of applying the coating agent to a surface of the vapor-deposited film layer 2 opposite to the base layer 4 to form a coating film composed of the coating agent, and drying the coating film to form the coating film 3.
It can be manufactured by the manufacturing method having.

In the base material (coating agent for forming the base layer), as a precursor of the organic polymer material, for example, when the organic polymer material is a hydrolyzed polycondensate of an organosilicon compound, the organosilicon compound and its hydrolysis are used. At least one selected from the group consisting of objects is used. In the case of a polyurethane resin, for example, the polyols and the isocyanate compound are used. In the case of a reaction product of the polyol and the organosilicon compound, the polyol and the organosilicon compound are used. In the case of a reaction product of the polyol, the organosilicon compound and the isocyanate compound, the polyol, the organosilicon compound and the isocyanate compound are used.
The hydrolyzate of the organosilicon compound can be obtained by a known method, typically using an acid or alkali catalyst, alcohol and water. It is preferable to use an acid catalyst because hydrolysis is easy to control. At this time, a generally known catalyst or the like may be added in order to further control the hydrolysis.
Examples of the liquid medium include water, organic solvents, and mixtures thereof.
The base material may further contain components other than the organic polymer material. Examples of other components include the same components as described above.
The base material can be prepared by blending each of the above components in an arbitrary ratio in a liquid medium.

As a base material coating method, a known wet coating method can be used, for example, a printing method such as an offset printing method, a gravure printing method, or a silk screen printing method, or a coating method such as a roll coat, a knife edge coat, or a gravure coat. And so on.
As a method for drying the coating film composed of the base material, known drying methods such as hot air drying, hot roll drying, and infrared irradiation can be used. The drying temperature of the coating film can be, for example, 50 to 200 ° C. The drying time varies depending on the thickness of the coating film, the drying temperature, and the like, but can be, for example, 1 second to 5 minutes.
The method for forming the thin-film film layer 2 and the method for forming the film layer 3 are the same as described above.

<Effect>
The gas barrier film 20 is provided on the opposite side of the resin base material 1, the vapor deposition film layer 2, and the resin base material 1 of the vapor deposition film layer 2 as in the gas barrier film 10 of the first embodiment. Since the coating layer 3 is provided, the gas barrier property is excellent, and the deterioration of the gas barrier property due to stretching isodynamic factors is small. Therefore, deterioration of the contents can be sufficiently suppressed when the packaging bag is used.
Further, in the gas barrier film 20, since the base layer 4 is further provided between the resin base material 1 and the vapor-deposited film layer 2, the adhesion between the resin base material 1 and the vapor-deposited film layer 2 is better. Therefore, even if the resin base material 1 contains a filler and has irregularities or waviness on the surface, the gas barrier property due to mechanical factors such as stretching is unlikely to decrease.

Although the present invention has been described above with reference to embodiments, the present invention is not limited to the above embodiments. Each configuration in the above embodiment and a combination thereof are examples, and the configuration can be added, omitted, replaced, and other changes can be made without departing from the spirit of the present invention.
For example, a base layer, a vapor-deposited film layer, and a coating layer may be provided on both sides of the resin base material.
The gas barrier film of the present invention further has a printing layer, an anchor coat layer, an overcoat layer, a light-shielding layer, an adhesive layer, a heat-sealing heat-sealing layer, and other functional layers, if necessary. You may.
When the gas barrier film of the present invention has a heat-sealing heat-sealing layer, the heat-sealing layer is arranged on at least one outermost layer of the gas barrier film. Since the gas barrier film has a heat-sealing layer, the gas barrier film can be sealed by a heat seal.
Examples of the heat-sealing layer include polyethylene, polypropylene, ethylene-vinyl acetate strong polymerization, and ethylene-methacrylic acid copolymer.
The heat-sealing layer is known, for example, polyurethane-based, polyester-based, or polyether-based, on one or both sides of a laminate in which a base layer, a vapor-deposited film layer, and a coating layer are sequentially formed on one or both sides of a resin base material. It can be laminated by a known dry laminating method, extrusion laminating method, or the like using an adhesive.

Hereinafter, the present invention will be specifically described based on Examples and Comparative Examples. However, the present invention is not limited to the following examples.
The materials used in each of the following examples are shown below.

(Resin base material)
Biaxially stretched polyethylene terephthalate film (hereinafter referred to as PET): Commercial product (manufactured by Toray Industries, Inc., trade name: P-60, thickness: 12 μm).
Biaxially stretched nylon film (hereinafter referred to as Ny): Commercial product (manufactured by Unitika, product surface: emblem (registered trademark) ONM, thickness; 15 μm).
Biaxially stretched polypropylene film (hereinafter referred to as OPP): Commercial product (manufactured by AJ Plast, trade name: PJ201, thickness: 20 μm).

(Material for forming a coating layer)
"Aqueous polyurethane resin (A)"
(A1): An aqueous dispersion of an aqueous polyurethane resin containing an acid group-containing polyurethane resin and a polyamine compound, an aqueous polyurethane dispersion "Takelac (registered trademark) WPB-341" manufactured by Mitsui Chemicals, Inc., having a solid content of 30% by mass.

"Water-soluble polymer (B)"
(B1): Polyvinyl alcohol having a saponification degree of 98 to 99% and a degree of polymerization of 500 (trade name: Poval PVA-105, manufactured by Kuraray Co., Ltd.).

"Inorganic layered mineral (C)"
(C1): Water-swellable synthetic mica (trade name: Somasif (registered trademark) MEB-3, manufactured by CO-OP CHEMICAL CO., LTD.), Average particle size 2.0 μm.
(C2): Montmorillonite (trade name: Kunipia (registered trademark) -F, manufactured by Kunimine Kogyo Co., Ltd.), average particle size 0.5 μm.

"Silane coupling agent (D)"
(D1): 3-glycidoxypropyltriethoxysilane (trade name: KBE-403, manufactured by Shinetsu Silicone Co., Ltd.).

(Material for forming the base layer)
Acrylic polyol: prepared by block copolymerization of hydroxyethyl methacrylate (HEMA), methyl methacrylate (MMA) and n-butyl methacrylate (BMA) so that the ratio of each monomer is 15/65/20 in molar ratio. Copolymer. Mass average molecular weight (Mw) = 10000.
γ-Isocyanatepropyltriethoxysilane: trade name KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.
Aliphatic xylylene diisocyanate: trade name D-110N, manufactured by Mitsui Chemicals, Inc.

(Examples 1 to 5)
A mixed material containing two or more kinds of metallic silicon, silicon monoxide and silicon dioxide is evaporated using a vacuum vapor deposition apparatus using an electron beam heating method to form a thin-film vapor deposition film layer made of silicon oxide having a thickness of 20 nm on PET. did.

The aqueous polyurethane resin (A) and the water-soluble polymer (B) were blended according to the types and blending ratios (% by mass) shown in Table 1, and then 10% by mass in the total aqueous medium was isopropanol and the solid content. A coating agent for forming a coating layer was prepared by diluting with ion-exchanged water and isopropanol so that the concentration was 8.2% by mass. Here, the blending ratio is the ratio of each component to the total solid content in the solid content, and the same applies to the following.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to form a coating layer having the thickness shown in Table 1. As a result, the gas barrier film of Examples 1 to 5 was obtained.

(Examples 6 to 7)
A thin-film film layer was formed on PET in the same manner as in Example 1.
The aqueous polyurethane resin (A) and the water-soluble polymer (B) are blended in the types and blending ratios (% by mass) shown in Table 1, then the inorganic layered mineral (C) is added, and then the all-water medium. A coating agent for forming a coating layer was prepared by diluting with ion-exchanged water and isopropanol so that 10% by mass of the content was isopropanol and the solid content concentration was 8.2% by mass.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to obtain a coating layer having the thickness shown in Table 1. As a result, the gas barrier film of Examples 6 to 7 was obtained.

(Examples 8 to 14)
A thin-film film layer was formed on PET in the same manner as in Example 1.
The aqueous polyurethane resin (A) and the water-soluble polymer (B) are blended in the types and blending ratios (% by mass) shown in Table 1, then the inorganic layered mineral (C) is added, and then the all-water medium. It was diluted with ion-exchanged water and isopropanol so that 10% by mass of the content was isopropanol and the solid content concentration was 8.2% by mass. A silane coupling agent (D) was added to the obtained diluted product in the types and blending ratios (% by mass) shown in Table 1 to prepare a coating agent for forming a coating layer.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to obtain a coating layer having the thickness shown in Table 1. As a result, the gas barrier films of Examples 8 to 14 were obtained.

(Examples 15 to 16)
Γ-Isocyanatepropyltriethoxysilane, acrylic polyol, and aliphatic xylylene diisocyanate are blended in a diluting solvent (ethyl acetate) at a mass ratio of 11:53:37 to add a base material (solid content concentration: 2% by mass). Prepared.
A base material was applied by a gravure coating method on one surface of PET prepared as a resin base material, and dried to form a base layer. The thickness of the base layer was 60 to 70 nm.
Then, in Example 15, a vapor-deposited film layer and a coating layer were formed in the same manner as in Example 1 except for the base layer to obtain a gas barrier film. In Example 16, a vapor-deposited film layer and a coating layer were formed in the same manner as in Example 8 except for the base layer to obtain a gas barrier film.

(Examples 17-18)
Example 17 is the same as Example 15 except that OPP is used as the resin base material, and Example 18 is the same as Example 16 in that the base layer, the vapor-deposited film layer and the coating layer are formed to have gas barrier properties. I got a film.

(Example 19)
A vapor-deposited film layer and a coating layer were formed in the same manner as in Example 8 except that Ny was used as the resin base material to obtain a gas barrier film.

(Examples 20 to 21)
Metallic aluminum is evaporated and oxygen gas is introduced on one surface of PET using a vacuum vapor deposition apparatus by an electron beam heating method to form a vapor deposition film layer made of aluminum oxide having a thickness of 20 nm on a resin base material. did.
Then, in Example 20, a coating layer was formed in the same manner as in Example 1 except for the vapor-deposited film layer to obtain a gas barrier film. In Example 21, a coating layer was formed in the same manner as in Example 8 except for the vapor-deposited film layer to obtain a gas barrier film.

(Comparative Example 1)
A thin-film film layer was formed in the same manner as in Example 1, and a gas barrier film of Comparative Example 1 was produced without forming a coating layer.

(Comparative Examples 2-3)
A thin-film film layer was formed in the same manner as in Example 1.
In water, the four components of the water-soluble polymer (B), the inorganic layered mineral (C), the tetraethoxysilane (TEOS), and the silane coupling agent (D), which are of the types shown in Table 2, are added to water at 35: 3: 57: A coating agent for forming a coating layer was prepared by blending in a mass ratio of 5.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to form a coating layer having the thickness shown in Table 1. As a result, the gas barrier films of Comparative Examples 2 and 3 were obtained.

(Comparative Examples 4 to 5)
A thin-film film layer was formed in the same manner as in Example 1.
The aqueous polyurethane resin (A) and the water-soluble polymer (B) were blended according to the types and blending ratios (% by mass) shown in Table 2, and then 10% by mass in the total aqueous medium was isopropanol and the solid content. A coating agent for forming a coating layer was prepared by diluting with ion-exchanged water and isopropanol so that the concentration was 8.2% by mass.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to obtain a coating layer. As a result, the gas barrier films of Comparative Examples 4 to 5 were obtained.

(Comparative Example 6)
A thin-film film layer was formed in the same manner as in Example 1.
The aqueous polyurethane resin (A) of the type shown in Table 2 is diluted with ion-exchanged water and isopropanol so that 10% by mass of the total aqueous medium is isopropanol and the solid content concentration is 8.2% by mass. , A coating agent for forming a coating layer was prepared.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to obtain a coating layer. As a result, the gas barrier film of Comparative Example 6 was obtained.

(Comparative Example 7)
A thin-film film layer was formed in the same manner as in Example 1.
The water-soluble polymer (B) of the type shown in Table 2 is diluted with ion-exchanged water and isopropanol so that 10% by mass of the total aqueous medium is isopropanol and the solid content concentration is 8.2% by mass. To prepare a coating agent for forming a coating layer.
The coating agent was applied onto the vapor-deposited film layer by a gravure coating method and dried to obtain a coating layer. As a result, the gas barrier film of Comparative Example 7 was obtained.

(Comparative Example 8)
A gas barrier film was obtained in the same manner as in Example 8 except that the thickness of the coating layer was 50 nm.

(Comparative Examples 9 to 10)
A base layer and a coating layer were formed on the resin base material in the same manner as in Example 1 in Comparative Example 9 and Example 8 in Comparative Example 10, except that the vapor-deposited film layer was not formed. As a result, gas barrier films of Comparative Examples 9 to 10 were obtained.

(Evaluation)
(1) Oxygen gas barrier property:
The gas barrier films obtained in Examples 1 to 21 and Comparative Examples 1 to 10 were subjected to an atmosphere of 30 ° C. and 70% RH using an oxygen permeability measuring device (trade name: OXTRAN-2 / 20, manufactured by MOCON). Below, the oxygen permeability (cm ³ / (m ² , day, MPa)) was measured. The results are shown in Tables 1 and 2 as "base paper OTR".

(2) Water vapor barrier property:
The gas barrier films obtained in Examples 1 to 21 and Comparative Examples 1 to 10 were used at 40 ° C. and 90% RH using a water vapor permeability measuring device (trade name: PERMATRAN-W-3 / 33, manufactured by MOCON). The water vapor permeability (cm ³ / (m ² · day)) was measured under the atmosphere of. The results are shown in Tables 1 and 2 as "base paper WVTR".

(3) Stretch resistance:
The gas barrier films obtained in Examples 1 to 21 and Comparative Examples 1 to 10 were cut into single sheets having a width of 130 mm in the TD direction and a width of 260 mm in the MD direction of the resin base material. This was stretched 2.5% in the MD direction at a speed of 6 mm / min by a tensile tester Tencilon. It was held in a stretched state for 1 minute and then opened. Then, the oxygen gas barrier property and the water vapor gas barrier property were evaluated under the same equipment and conditions as described above. The results are shown in Tables 1 and 2 as "stretched OTR" and "stretched WVTR", respectively.

(4) Laminate strength:
Polyester urethane adhesives (trade names: Takelac A-969, Takenate A-5, Mitsui Chemicals, Inc.) were subjected to dry lamination processing on the coating layer side of the gas barrier films obtained in Examples 1 to 21 and Comparative Examples 1 to 10. An unstretched polypropylene film having a thickness of 30 μm (trade name: CPP GLC, manufactured by Mitsui Chemicals Tohcello Co., Ltd.) was laminated and cured at 40 ° C. for 48 hours to obtain a laminated film.
This laminated film is cut into strips with a width of 15 mm, and the gas barrier film is peeled from the unstretched polypropylene film by 90 ° at a speed of 300 mm / min by a tensile tester Tencilon to increase the lamination strength (N / 15 mm). It was measured. The results are shown in Tables 1-2.

In Tables 1 and 2, the numerical values shown on the right side of the reference numerals ((A1), (B1), etc.) indicating the types of each component of the coating layer indicate the blending ratio.
"(A) / (B)" is a mass ratio of the aqueous polyurethane resin (A) and the water-soluble polymer (B) in terms of solid content (water-based polyurethane resin (A) / water-soluble polymer (B)). Shown.
The unit of the base paper OTR and the stretched OTR is cm ³ / (m ² · day · MPa), the unit of the base paper WVTR and the stretched WVTR is cm ³ / (m ² · day), and the unit of the laminate strength is N / 15 mm.

From the results in Tables 1 and 2, the gas barrier film of Examples 1 to 21 was excellent in oxygen gas barrier property because it provided the resin base material, the vapor-deposited film layer, and the coating layer in the present invention. In addition, the water vapor barrier property was sufficiently high. In addition, these gas barrier properties were sufficiently maintained even after stretching, and the resistance to mechanical factors was excellent.
Among the above, the gas barrier films of Examples 15 to 16 use PET as a resin base material and have an underlayer, so that they are excellent in oxygen gas barrier property and water vapor barrier property, and these gas barrier properties are extended. It was held particularly well afterwards.
Since the gas barrier film of Comparative Example 1 did not have a coating layer, both the gas barrier property and the resistance to mechanical factors were inferior. In the gas barrier films of Comparative Examples 2 to 7, the mass ratio of the aqueous polyurethane resin (A) and the water-soluble polymer (B) as the material forming the coating layer was out of the range of 85/15 to 10/90. Either gas barrier property or resistance to mechanical factors was inferior. Since the thickness of the coating layer of the gas barrier film of Comparative Example 8 was less than 100 nm, the original performance of the coating layer was not exhibited, and the gas barrier property was inferior. Since the gas barrier films of Comparative Examples 9 to 10 did not have a vapor-deposited film layer, they were inferior in gas barrier properties and resistance to mechanical factors.

The gas barrier film of the present invention has excellent gas barrier properties, and the deterioration of gas barrier properties due to mechanical factors such as stretching is small. Therefore, when the content is contained as a packaging material, deterioration of the content due to water vapor or the like can be sufficiently suppressed. Further, when the packaging bag or the like is processed, or when a force is applied to the packaging bag or the like during long-distance transportation or the like, the deterioration of the gas barrier property is small. Therefore, the gas barrier film of the present invention is useful as a packaging material.

1 Resin base material 2 Deposited film layer 3 Coating layer 4 Underlayer 10 Gas barrier film 20 Gas barrier film

Claims (6)

A resin base material, a vapor-deposited film layer, and a coating layer provided on the opposite side of the vapor-deposited film layer from the resin base material are provided.
The coating layer is a layer formed from a coating agent.
The coating agent contains an aqueous polyurethane resin (A) containing an acid group-containing polyurethane resin and a polyamine compound, and a water-soluble polymer (B).
The mass ratio of the aqueous polyurethane resin (A) to the water-soluble polymer (B) in terms of solid content is 85/15 to 10/90.
The coating agent does not contain the silane coupling agent (D) or contains the silane coupling agent (D) in an amount of 10% by mass or less, and is a metal alkoxide other than the silane coupling agent and a hydrolyzed condensate thereof. Does not include any of
A gas barrier film having a coating layer having a thickness of 100 nm or more. The gas barrier film according to claim 1, wherein the resin base material contains either one or both of a polyester resin and a polyamide resin. An underlayer is further provided between the resin substrate and the vapor-deposited film layer.
The underlayer is a polyol, an organosilicon compound and / or a hydrolyzed polycondensate of the organosilicon compound, a polyurethane resin, a reaction product of the polyol and the organosilicon compound, and the polyol, the organosilicon compound and isocyanate. The gas barrier film according to claim 1 or 2, which comprises at least one organopolymer material selected from the group consisting of reaction products with compounds. The gas barrier film according to any one of claims 1 to 3, wherein the coating agent further contains an inorganic layered mineral (C). The gas barrier film according to claim 4, wherein the inorganic layered mineral (C) contains a water-swellable synthetic mica. The gas barrier film according to any one of claims 1 to 5 , wherein the thickness of the coating layer is 100 nm to 1400 nm.

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