JP7068617B2 - Gas barrier laminated film - Google Patents

Description

The present invention relates to a gas barrier laminated film having transparency, excellent gas barrier property against water vapor, oxygen, etc., and suitable for applications requiring high moisture resistance such as confectionery, daily necessities, electronic parts, pharmaceuticals, and the like.

Conventionally, as a gas barrier film, a film in which a metal thin film such as aluminum and a thin film of an inorganic oxide such as silicon oxide or aluminum oxide are laminated on the surface of a plastic film has been known. Among them, the film on which thin films of inorganic oxides such as silicon oxide, aluminum oxide, and mixtures thereof are laminated is transparent and the contents can be confirmed, so that it is used for foods, daily necessities, electronic parts, pharmaceuticals, etc. Widely used in packaging applications. (See, for example, Patent Document 1)
Pinholes and cracks are likely to occur in these inorganic thin films in the thin film forming process, and the inorganic thin film layer is cracked and cracked in the processing process, so that the expected sufficient gas barrier property is not obtained.

Further, many gas barrier films by coating the surface of a plastic film with a resin composition have also been proposed. In particular, polyvinyl alcohol (hereinafter referred to as PVA) and ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) have high oxygen barrier properties and have been put into practical use as gas barrier coating agents, and are widely known as known techniques. (For example, see Patent Document 2), but gas barrier properties have not been obtained.

Therefore, for the purpose of compensating for the lack of barrier properties of the vapor-deposited film with a gas barrier resin, a technique of laminating a vinyl alcohol-based resin as described above, particularly a barrier resin such as PVA, on an inorganic thin film layer is widely known. Due to the hydrophilicity peculiar to PVA, it absorbs and swells external moisture, which causes some troubles such as peeling of the coat and blocking in the roll when the film is wound into a roll.

Japanese Patent No. 2929609 Japanese Unexamined Patent Publication No. 7-80986

The present invention has been made in the background of the problems of the prior art. That is, an object of the present invention can be used for packaging applications such as confectionery, daily necessities, electronic parts, pharmaceuticals, etc., which require a high degree of moisture resistance, which cannot be obtained with a conventional thin-film vapor-deposited film, and blocking with a roll is possible. It is an object of the present invention to provide a gas barrier laminated film and a gas barrier packaging bag which do not occur.

As a result of diligent studies, the present inventors have found that the above problems can be solved by the means shown below, and have arrived at the present invention.
That is, the present invention has the following configuration.

1. 1. A gas barrier laminated film obtained by laminating an inorganic thin film layer and a gas barrier resin composition layer on at least one surface of a base film, wherein the gas barrier resin composition layer is a structural unit represented by the following formula 1. Polyvinyl alcohol-based copolymer resin (component A) having a carbonyl group in the molecule, polyvinyl alcohol-based (co) polymer resin (component B) having a carbonyl group in the molecule, hydrazine-based cross-linking agent (component C), and an inorganic layered form. A gas barrier laminated film comprising a compound (component D).

（ただし、R_１およびR_２はそれぞれ独立して炭素数１～３の炭化水素基である）

(However, R ₁ and R ₂ are each independently a hydrocarbon group having 1 to 3 carbon atoms).

2. 2. The gas barrier resin composition layer is characterized by satisfying the following conditions 1 to 3. The gas barrier laminated film according to.
Condition 1: When the mass of the component A contained in the barrier coating agent forming the gas barrier resin composition layer is WA and the mass of the component B contained in the barrier coating agent is WB, WA. / WB = 20/80 to 70/30.
Condition 2: When the mass of the component B is WB and the mass of the component C is WC, WB / WC = 95/5 to 70/30.
Condition 3: Further, when the mass of the component D contained in the barrier coating agent is WD, (WA + WB) / WD = 95/5 to 70/30.
3. 3. 1. The component A is a saponified product of a copolymer of a radically polymerizable monomer containing a radically polymerizable monomer represented by the following formula 2 and a vinyl ester monomer. Or 2. The gas barrier laminated film according to.

（Ｒ_１及びＲ_２はそれぞれ独立して炭素数１～３の炭化水素基であり、Ｒ_３及びＲ_４は、それぞれ独立して水素原子または－CO－Ｒ_５基（式中、Ｒ_５は、好ましくはメチル基、プロピル基、ブチル基、ヘキシル基またはオクチル基であり、かかるアルキル基は必要に応じて、ハロゲン基、水酸基、エステル基、カルボン酸基、スルホン酸基等の置換基を有していてもよい。）

(R ₁ and R ₂ are independently hydrocarbon groups having 1 to 3 carbon atoms, and R ₃ and R ₄ are independent hydrogen atoms or -CO-R ₅ groups (in the formula, R ₅ is). , Preferably a methyl group, a propyl group, a butyl group, a hexyl group or an octyl group, and such an alkyl group has a substituent such as a halogen group, a hydroxyl group, an ester group, a carboxylic acid group or a sulfonic acid group, if necessary. You may be doing it.)

4. 1. The component A is a polyvinyl alcohol-based copolymer resin represented by the following formula 3. ~ 3. The gas barrier laminated film according to any one of.

（ただし、R_１およびR_２は前記と同じ定義、Ｘは共重合成分として用いられたラジカル重合性モノマーの分子構造に由来し、他の二つの構造単位に該当しない構造単位を表わす。ｌ、ｍ、ｎは、一分子あたりのそれぞれの構造単位の平均数を表し、ｌ＋ｍ＋ｎ＝３００～４０００、ｌ／（ｌ＋ｍ＋ｎ）＝０．００１～０．２、ｍ／（ｌ＋ｍ＋ｎ）＝０．８～０．９９、ｎ／（ｌ＋ｍ＋ｎ）＝０～０．１の関係を満足する。）

(However, R ₁ and R ₂ have the same definition as above, and X represents a structural unit derived from the molecular structure of the radically polymerizable monomer used as a copolymerization component and does not correspond to the other two structural units. m and n represent the average number of each structural unit per molecule, l + m + n = 300 to 4000, l / (l + m + n) = 0.001 to 0.2, m / (l + m + n) = 0.8 to 0. .99, n / (l + m + n) = 0 to 0.1 is satisfied.)

5. 1. The component B is a vinyl alcohol-based (co) polymer resin that satisfies the following conditions 4 and / or condition 5. ~ 4. The gas barrier laminated film according to any one of.
Condition 4: A saponified product of a copolymer of a radically polymerizable monomer containing a vinyl ester monomer and a radically polymerizable monomer containing a carbonyl group.
Condition 5: An acetoacetylated product of a kenside of a (co) polymer of a radically polymerizable monomer containing a vinyl ester monomer.
6. 1. The component B is a polyvinyl alcohol-based (co) polymer resin containing a structural unit represented by the following formula 4 and / or a structural unit represented by the following formula 5 in the molecule. ~ 5. The gas barrier laminated film according to any one of.

（ただし、Ｒ_６は水素またはメチル基である。）

(However, _R6 is a hydrogen or methyl group.)

7. The gas barrier laminated film according to any one of claims 1 to 6, wherein the component B is a polyvinyl alcohol-based (co) polymer resin represented by the following formula 6.

（ただし、R_６は水素またはメチル基である。また、Ｙは共重合成分として用いられたラジカル重合性モノマーの分子構造に由来し、他の三つの構造単位に該当しない構造単位を表わす。ｏ＋ｐ＋ｑ＋ｒは３００～４０００であって、（ｏ＋ｐ）／（ｏ＋ｐ＋ｑ＋ｒ）＝０．００１～０．２５、ｑ／（ｏ＋ｐ＋ｑ＋ｒ）＝０．７５～０．９９９、ｒ／（ｏ＋ｐ＋ｑ＋ｒ）＝０～０．２の関係を満足する。）

(However, R ₆ is a hydrogen or a methyl group. Further, Y is derived from the molecular structure of the radically polymerizable monomer used as a copolymerization component and represents a structural unit that does not correspond to the other three structural units. O + p + q + r. Is 300 to 4000, and (o + p) / (o + p + q + r) = 0.001 to 0.25, q / (o + p + q + r) = 0.75 to 0.999, and r / (o + p + q + r) = 0 to 0.2. Satisfy the relationship.)

8. 1. The inorganic thin film layer contains at least one kind of inorganic oxide containing silicon oxide and / or aluminum oxide. ~ 7. The gas barrier laminated film according to any one of.
9. A gas-barrier packaging bag using the gas-barrier laminated film according to any one of 1 to 8 above, which is arranged in the order of a base film layer, an inorganic thin film layer, and a gas-barrier resin composition layer from the outside of the bag. Gas barrier packaging bag.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a gas barrier laminated film and a gas barrier packaging bag which have a higher gas barrier property against water vapor, oxygen and the like than conventional ones and do not cause blocking.

The present invention is a gas barrier laminated film in which an inorganic thin film layer and a gas barrier resin composition layer are laminated on at least one surface of a base film, and the gas barrier resin composition is a vinyl alcohol-based copolymer resin. (Component A), a vinyl alcohol-based polymer resin having a carbonyl group in the molecule (Component B), a hydrazine-based cross-linking agent (Component C), an inorganic layered compound (Component D), and an aqueous medium (Component E). Although it is a gas barrier laminated film composed of, each component will be described in detail below.

1. 1. Base film The base film used in the present invention is a film made of an organic polymer, which is melt-extruded and then stretched, cooled, and heat-fixed in the longitudinal direction and / or the width direction as needed. Examples of the organic polymer include polyamide represented by nylon 4.6, nylon 6, nylon 6.6, nylon 12, polyethylene terephthalate, polybutylene terephthalate, polyester represented by polyethylene-2,6-naphthalate, and polyethylene. , Polypropylene, Polyethylene, etc., Polyvinyl Chloride, Polyvinyl Chloride, Polyvinyl Alcohol, Total Aromatic Polyamide, Polyamideimide, Polyester, Polyetherimide, Polysulfone, Polystyrene, Polylactic Acid, etc. .. Of these, polyester or polyamide is preferable, and polyester is more preferable.
Further, the base film in the present invention may be a laminated film. The type of each layer, the number of layers, the layering method, and the like in the case of forming a laminated film are not particularly limited, and can be arbitrarily selected from known methods according to the purpose.
Further, a small amount of other organic polymers may be copolymerized or blended with the base film. As for the method for producing the base film, existing methods such as a coextrusion method and a casting method can be used.

Among these, specific examples of preferable polymers include polycaproamide (nylon 6), poly-ε-aminoheptanoic acid (nylon 7), poly-ε-aminononanoic acid (nylon 9), and polyundecaneamide (nylon 11). ), Polylaurin lactam (nylon 12), Polyethylenediamine adipamide (nylon 2.6), Polytetramethylene adipamide (nylon 4.6), Polyhexamethylene adipamide (nylon 6.6), Polyhexa Methylene sebacamide (nylon 6/10), polyhexamethylene dodecamide (nylon 6.12), polyoctamethylene dodecamide (nylon 6.12), polyoctamethylene adipamide (nylon 8.6), polydeca Methylene adipamide (nylon 10/6), polydecamethylene sebacamide (nylon 10/10), polydodecamethylene dodecamide (nylon 12.12), polymeridamine-6 nylon (MXD6), etc. can be mentioned. It may be a copolymer containing these as a main component, and examples thereof include caprolactam / laurinlactam copolymer, caprolactam / hexamethylenediammonium adipate copolymer, and laurinlactam / hexamethylenediammonium adipate. Polymers, hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer, ethylene diammonium adipate / hexamethylene diammonium adipate copolymer, caprolactam / hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer And so on. It is also effective to add a plasticizer such as aromatic sulfonamides, p-hydroxybenzoic acid, and esters, an elastomer component having a low elastic modulus, and lactams to these polyamides as a flexibility modifying component of the film. be. Of these, polycarbonate (nylon 6) is preferable.

Further, as specific examples of preferable polyesters, polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate and the like are used, and among these, polyethylene terephthalate is preferable. Further, a copolymer containing these as a main component may be used, and when a polyester copolymer is used, the main component of the dicarboxylic acid component is terephthalic acid, isophthalic acid, phthalic acid or 2,6-naphthalenedicarboxylic acid. In addition to aromatic dicarboxylic acids such as, and polyfunctional carboxylic acids such as trimellitic acid and pyromellitic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid are used.
Ethylene glycol or 1,4-butanediol is used as the main component of the glycol component, but other aliphatic glycols such as diethylene glycol, propylene glycol and neopentyl glycol, and aromatic glycols such as p-xylylene glycol are used. Alicyclic glycols such as 1,4-cyclohexanedimethanol, polyethylene glycols having an average molecular weight of 150 to 20000, and the like can also be used.
The ratio of the preferable copolymerization component in the polyester is 2% or less. When the copolymerization component exceeds 20%, the film strength, transparency, heat resistance and the like may be inferior.

Further, known additives such as an ultraviolet absorber, an antioxidant, a plasticizer, a lubricant, and a colorant may be added to the above-mentioned organic polymer, and the transparency as a base film is particularly limited. Although it is not a thing, when it is used as a transparent packaging material laminate, it is desirable that it has a transmittance of 50% or more.
As long as the object of the present invention is not impaired, the base film in the present invention may be subjected to corona discharge treatment, glow discharge, flame treatment, surface roughening treatment, etc. prior to laminating the thin film layer. A surface treatment may be applied, or a known anchor coating treatment, printing, or decoration may be applied. The thickness of the plastic film in the present invention is preferably in the range of 1 to 500 μm, more preferably in the range of 2 to 300 μm, and most preferably in the range of 3 to 100 μm.
From the viewpoint of imparting mechanical strength, the base film is preferably a stretched film stretched in at least one direction in the vertical direction or the horizontal direction, and is biaxially stretched in two directions in the vertical direction and the horizontal direction. It is preferably a film. As the stretching method of the biaxially stretched film, any method such as simultaneous biaxial stretching or sequential biaxial stretching can be adopted.

2. 2. Inorganic thin film layer The inorganic thin film layer in the present invention is preferably an inorganic oxide thin film. For example, the thin film layer is not particularly limited as long as it can be formed into a thin film such as silicon oxide, aluminum oxide, and magnesium oxide, but is preferably a thin film layer containing at least one kind of inorganic oxide containing silicon oxide and / or aluminum oxide.
The thin film layer containing at least one kind of an inorganic oxide containing silicon oxide or aluminum oxide referred to here is a thin film formed from an inorganic oxide by a known method.
The silicon oxide referred to here is composed of a mixture of various silicon oxides such as Si, SiO and SiO ₂ , and the aluminum oxide is composed of a mixture of various aluminum oxides such as AlO and Al ₂ O ₃ in each oxide. The amount of oxygen bound in the silicon varies depending on the production conditions.

The specific gravity of the binary inorganic oxide thin film composed of silicon oxide and aluminum oxide is the specific gravity of the thin film and the content of aluminum oxide in the thin film (mass%) D = 0.01A + b (D: specific gravity of the thin film, A: in the thin film). The b value is preferably 1.2 to 2.2, more preferably 1.7 to 2.1, when expressed by the relational expression (content of aluminum oxide).

Further, the relationship between the value of the specific gravity of the binary inorganic oxide thin film and the content (% by mass) of aluminum oxide in the inorganic oxide thin film is determined by D = 0.01A + b (D: specific gravity of the thin film, A: thin film). When the b value is smaller than 1.6, the structure of the silicon oxide / aluminum oxide thin film becomes rough, and the b value is larger than 2.2. In the case of, the silicon oxide / aluminum oxide thin film tends to be hard.

The content of aluminum oxide in the binary inorganic oxide thin film is preferably 20 to 99% by mass, more preferably 20 to 75% by weight.
When the content of aluminum oxide in the binary inorganic oxide thin film is less than 20% by mass, the gas barrier property is not always sufficient, and when the amount of aluminum oxide in the binary inorganic oxide thin film exceeds 99% by mass, The flexibility of the vapor-filmed film is reduced, the gas barrier laminated body is relatively vulnerable to bending and dimensional changes, and the effect of the combined use of the two may be reduced.

In the present invention, the film thickness of the inorganic thin film layer is usually 1 to 50 nm, preferably 5 to 30 nm. If the film thickness is less than 1 nm, it is difficult to obtain a satisfactory gas barrier property, and if the film thickness exceeds 50 nm, the corresponding effect of improving the gas barrier property cannot be obtained, and the bending resistance and the manufacturing cost are increased. On the contrary, it is disadvantageous in terms of points.

Explaining a typical manufacturing method for forming an inorganic thin film layer by forming an inorganic oxide-based thin film containing silicon oxide and / or aluminum oxide, the thin film forming method by the vapor deposition method includes a vacuum heating vapor deposition method, a sputtering method, and ion plating. A physical vapor deposition method such as a method, a CVD method (chemical vapor deposition method), or the like is appropriately used. For example, when the vacuum vapor deposition method is adopted, Al or a mixture of SiO ₂ and Al ₂ O ₃ or a mixture of SiO ₂ and Al is used as the vapor deposition raw material. For heating, resistance heating, high frequency induction heating, electron beam heating, etc. can be adopted, and oxygen, nitrogen, hydrogen, argon, carbon dioxide gas, steam, etc. can be introduced as reaction gas, ozone addition, ion assist, etc. It is also possible to adopt reactive vapor deposition using means such as. Further, the film forming conditions can be arbitrarily changed, such as applying a bias to the plastic film and heating or cooling the plastic film. The vapor deposition material, reaction gas, substrate bias, heating / cooling, and the like can be similarly changed when the sputtering method or the CVD method is adopted.

3. 3. Gas barrier resin composition layer The gas barrier resin composition layer in the present invention is a vinyl alcohol-based copolymer resin (component A), a vinyl alcohol-based polymer resin having a carbonyl group in the molecule (component B), and a hydrazine-based crosslink. It preferably contains an agent (component C) and an inorganic layered compound (component D). The gas barrier coating agent for forming the gas barrier resin composition layer will be described later.

(1) Gas barrier resin, cross-linking agent Conventionally, vinyl alcohol-based resins such as PVA are known to have high oxygen barrier properties by themselves, and have been widely used as oxygen barrier resins. In addition, it has been widely used as a gas barrier material because it exhibits a water vapor barrier property when used in a limited manner in a low humidity region in combination with an inorganic substance. However, since there are many hydroxyl groups in the resin, it is easily dissolved in water, and when used as a film coating agent, it absorbs moisture from the outside, causing the film to block from the melted resin as a starting point, such as printing and laminating. There were frequent problems with the film breaking during processing. To this end, means for improving the water resistance of the resin by adding a metal compound cross-linking agent such as titanium or zirconium have been used, but the effect is insufficient. To solve these problems, the blocking resistance was significantly improved by using a coating agent in which a vinyl alcohol-based polymer resin having a carbonyl group in the molecule and a hydrazine-based cross-linking agent were used. However, the required level of barrier property (particularly moisture-proof property) in the market is increasing year by year, and the moisture-proof property is insufficient. Therefore, it has been found that a vinyl alcohol-based polymer resin having a carbonyl group in the molecule and a vinyl alcohol-based copolymer resin having the structural unit of the above formula 1 are mixed and used in combination to achieve both blocking resistance and moisture resistance. rice field.

The blocking resistance referred to here means the presence or absence of blocking of the film when the film roll is unwound. When a film having no blocking resistance is unwound, the films stick to each other and block, resulting in film breakage. The blocking-resistant film does not block due to sticking between the films, and can be unwound smoothly. It is considered that the mechanism of blocking generation occurs when a part of the coat layer is dissolved by water and adheres to the overlapping films. Therefore, it is considered that the coat layer of the film having no blocking resistance is easily peeled off by rubbing it with water. Therefore, in the evaluation of the blocking resistance in the present invention, the presence or absence of adhesion between the films when the film roll was unwound and the degree of peeling of the coat layer when soaked in water were evaluated by a rubbing test.
Further, the moisture-proof property means a water vapor barrier property (WVTR). In the present invention, the produced film was evaluated by WVTR under the conditions of 40 ° C. and 90% RH.

4. Gas barrier coating agent The gas barrier coating agent for forming the gas barrier resin composition layer of the present invention includes a modified vinyl alcohol-based (co) polymer resin (component A, component B) and a hydrazine-based cross-linking agent (component). C), an inorganic layered compound (component D) and a solvent (sometimes referred to as component E).

<Modified vinyl alcohol-based (co) polymer resin>
A vinyl alcohol-based copolymer resin (component A) having a structural unit represented by the following formula 1 in the molecule, which is contained in the gas barrier coating agent of the present invention, will be described.

（R_１およびR_２はそれぞれ独立して炭素数１～３の炭化水素基である。）

(R ₁ and R ₂ are each independently a hydrocarbon group having 1 to 3 carbon atoms.)

Details of the material for synthesizing the component A, the synthesis method, the saponification method and the like are disclosed in Japanese Patent Application Laid-Open No. 2006-176589. The polyvinyl alcohol-based copolymer resin obtained by using the material, the synthesis method, the saponification method, etc. described as particularly suitable in the same publication is also suitable as the component A of the gas barrier coating agent of the present invention. Available.
Here, as a method for introducing the structural unit represented by the above formula 1 into the molecule of the component A, a method of copolymerizing a vinyl ester-based monomer and a radically polymerizable monomer represented by the following formula 2 can be used. The obtained copolymer is saponified to obtain a polyvinyl alcohol-based copolymer resin.

In the above formula 2, R ₁ and R ₂ are independent hydrocarbon groups having 1 to 3 carbon atoms, and R ₃ and R ₄ are independent hydrogen atoms or -CO-R ₅ groups (respectively). _In the formula, R5 is preferably a methyl group, a propyl group, a butyl group, a hexyl group or an octyl group, and such an alkyl group may be a halogen group, a hydroxyl group, an ester group, a carboxylic acid group or a sulfonic acid group, if necessary. It may have a substituent such as).

Examples of the radically polymerizable monomer represented by the above formula 2 include 1,4-dihydroxy-2-butene, 1,4-diasiloxy-2-butene, 1-hydroxy-4-acyloxy-2-butene, and 1,4. -Diacyloxy-1-methyl-2-butene, 1,5-diasiloxy-2-pentene, 1,6-diasiloxy-2-hexene, 1,6-diasiloxy-3-hexene and the like, among which copolymerization In terms of excellent reactivity and industrial handling, 1,4-diasiloxy-2-butene in which R1 and R2 are methylene groups, R3 and R4 are -CO-R5, and R5 is an alkyl group is preferable. Of these, 1,4-diacetoxy-2-butene in which R3 is a methyl group is more preferable.
The polyvinyl alcohol-based copolymer resin obtained from the above copolymerization components and the production method can be simply represented by the following formula 3.

Here, R ₁ and R ₂ are the same as the definition of Equation 1. Further, X is derived from the molecular structure of the radically polymerizable monomer used as the copolymerization component, represents a structural unit that does not correspond to the other two structural units, and specifically, is a radically polymerizable monomer represented by the formula 2. Sites where at least one of R ₃ or R ₄ is -CO-R ₅ even after being copolymerized and saken, sites where vinyl ester monomers were copolymerized and not saken, and The copolymerized sites of other radically polymerizable monomers used as needed fall under this category. Although the formula 3 simply indicates the form of the block copolymer of the three structural units, the arrangement of the three structural units is not particularly limited and includes a random copolymer. l, m, and n represent the average number of each structural unit per molecule, l + m + n = 300 to 4000, l / (l + m + n) = 0.001 to 0.2, m / (l + m + n) = 0.8. The relationship of ~ 0.99 and n / (l + m + n) = 0 to 0.1 is satisfied.
Examples of commercially available products of such component A include OKS-1109 and OKS-8049 (manufactured by Nippon Synthetic Chemistry Co., Ltd.).

In the gas barrier coating agent for forming the gas barrier resin composition layer of the present invention, a vinyl alcohol-based (co) polymer resin having a carbonyl group in the molecule (hereinafter, may be referred to as component B) is used. contains. The term "(co) polymerization" includes both homopolymerization using one kind of radically polymerizable monomer and copolymerization using two or more kinds of radically polymerizable monomers, and includes "(co) heavy". The term "combined resin" refers to both a homopolymer resin obtained by homopolymerizing one type of radically polymerizable monomer and a copolymer resin obtained by copolymerizing two or more types of radically polymerizable monomers. include.
First, as a method for introducing a carbonyl group into the molecule of component B, (1) a vinyl ester-based monomer and a carbonyl group in the molecule are provided, and carbonyl groups are removed from the molecule of the polyvinyl alcohol-based copolymer by saponification. A method of copolymerizing with a carbonyl group-containing monomer that is not removed, (2) a method of polymerizing a polymerization component containing a vinyl ester-based monomer, then Kenting to generate a hydroxyl group, and further acetylating the hydroxyl group, etc. Is available.
Specifically, as the vinyl ester-based monomer of (1), those listed above can be used as they are. Examples of the carbonyl group-containing monomer include vinyl ketones, diacetone (meth) acrylamide, and the like, and diacetone (meth) acrylamide is preferable.
As a method for copolymerizing the vinyl ester-based monomer, the carbonyl group-containing monomer, and other radically polymerizable monomers, if necessary, as long as the effects of the present invention are not impaired, a usual solution polymerization method or lumpy form is used. Known methods such as a polymerization method and an emulsion polymerization method can be used without particular limitation.
According to this method, for example, when diacetone (meth) acrylamide is used as a copolymerization component, the structural unit represented by the following formula 4 is introduced into the molecule of the polyvinyl alcohol-based copolymer resin as the component B. Can be done.

（ただし、Ｒ_６は水素またはメチル基である）

(However, _R6 is a hydrogen or methyl group)

Further, a method of first synthesizing a polyvinyl alcohol-based (co) polymer resin and then introducing a carbonyl group by acetoacetylation of a hydroxyl group in the molecule can also be used.
Specifically, a method in which a gaseous or liquid diketen is directly reacted with a synthesized polyvinyl alcohol-based (co) polymer resin, an organic acid such as acetic acid is previously adsorbed and occluded, and then an inert gas is used. Diquetene is reacted by a method of reacting gaseous or liquid occlusion in an atmosphere, or a method of spraying a mixture of organic acid and occlusion to react (reaction generation step), and then an alcohol having 1 to 3 carbon atoms. It can be produced by washing and removing unreacted diketen using (washing step) and then drying under predetermined conditions (drying step).
According to this method, the structural unit represented by the following formula 4 can be introduced into the molecule of the polyvinyl alcohol-based (co) polymer resin as the component B.

The polyvinyl alcohol-based polymer resin obtained from the above copolymerization components and the production method can be simply represented by the following formula 6.

_R6 is a hydrogen or methyl group. Further, Y is derived from the molecular structure of the radically polymerizable monomer used as the copolymerization component, represents a structural unit that does not correspond to the other three structural units, and specifically, a vinyl ester-based monomer is copolymerized. Later, the non-kenylated sites and the copolymerized sites of other radically polymerizable monomers used as needed fall under this category. Although the formula 6 simply indicates the form of the block copolymer of the four structural units, the arrangement of the four structural units is not particularly limited and includes a random copolymer. o + p + q + r is 300 to 4000, and (o + p) / (o + p + q + r) = 0.001 to 0.25, q / (o + p + q + r) = 0.75 to 0.999, r / (o + p + q + r) = 0 to 0.2. Satisfy the relationship.

<Hydrazine-based cross-linking agent>
The hydrazine-based cross-linking agent (component C) contained in the gas barrier coating agent of the present invention is a compound having two or more hydrazine residues in the molecule, and is preferably an alkylene dihydrazine represented by the following formula 7. Alternatively, a saturated aliphatic dibasic acid, a dihydrazide compound of an unsaturated dibasic acid, or the like can be used.

（式中、Ｚは１～８個の炭素を有するアルキレン基、あるいは１～１０個の炭素を有する飽和または不飽和二塩基酸の残基を表す。）

(In the formula, Z represents a residue of an alkylene group having 1 to 8 carbons or a saturated or unsaturated dibasic acid having 1 to 10 carbons.)

Specific examples of the alkylene dihydrazine include methylene dihydrazine, ethylene dihydrazine, propylene dihydrazine, butyrene hydrazine and the like. Examples of the dihydrazide compound of the saturated aliphatic dibasic acid include oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutarate dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide and the like, and further, unsaturated dibasic acid. Examples of the dihydrazide compound include phthalic acid dihydrazide, fumaric acid dihydrazide, and itaconic acid dihydrazide.

<Inorganic layered compound>
The inorganic layered compound (component D) contained in the gas barrier coating agent of the present invention has a cationic metal atom or an inorganic atomic group between layers, and is subjected to swelling / opening treatment with a solvent described later or separately. By the solvent, the metal atom or the inorganic atomic group is ionized and eluted in the solvent to utilize the property of opening.
The component D has a structure in which a large number of thin film-like layers having a thickness of about 0.5 to 3 nm and a width of about 100 nm to several μm are laminated, and the layers have a high gas barrier capacity as much as possible. Therefore, even if the content of the component D in the gas barrier coating agent is the same, the gas barrier property of the coating film formed is higher in the system having a more advanced cleavage. Further, in a system in which the degree of cleavage is more advanced when the coating film is subjected to elongation or peeling stress, it is possible to suppress a decrease in fracture strength due to delamination of the uncleaved portion of the inorganic layered compound. As described above, the component D is a material that exhibits the effect of the present invention in that it can be easily cleaved closer by ionizing the cationic metal atoms or the like between the layers with water or the like and eluting them in the solvent. Is extremely suitable.
As these inorganic layered compounds, clay minerals having swelling properties are preferable, and specifically, a type having a two-layer structure having an octahedral layer having aluminum, magnesium, or the like as a central metal above the tetrahedral layer of silica. The tetrahedral layer of silica is classified into a type having a three-layer structure in which an octahedral layer having aluminum, magnesium or the like as a central metal is sandwiched from both sides. Examples of the former include kaolinites and antigolites belonging to the Jamon stone group, and examples of the latter include smectites, vermiculites and mica depending on the number of interlayer cations.
Specifically, kaolinite, nacrite, dikite, halosite, hydrous halosite, antigolite, chrysotile, pyrophyllite, montmorillonite, byderite, saponite, hectrite, saponite, stepvensite, tetrasilic mica, sodium teniolite, Muscovite, margarite, talc, vermiculite, phlogopite, zansophyllite, chlorite and the like can be mentioned, and these may be natural products or synthetic products. Further, scaly silica and the like can also be used. These may be used alone or in combination of two or more.
Among these, the use of montmorillonite is preferable from the viewpoint of excellent gas barrier performance and coating suitability when used as a coating agent.

<Solvent>
As the solvent contained in the gas barrier coating agent of the present invention, either an aqueous solvent or a non-aqueous solvent capable of dissolving the polyvinyl alcohol-based (co) polymer resin can be used.
As the aqueous solvent, water can be used as a main component, and a water-soluble organic solvent can be used in combination as needed. Here, examples of the water-soluble organic solvent that can be used in combination include lower alcohols such as methanol, ethanol and isopropanol, polyhydric alcohols such as ethylene glycol and propylene glycol and derivatives thereof, ethyl acetate and methyl ethyl ketone. By using such an organic solvent, it is possible to improve the solubility of the component A and the component B, adjust the dryness of the gas barrier coating agent, and adjust the wettability to the base film.
Further, if necessary, an organic solvent that dissolves the component A and the component B can be used as a non-aqueous solvent. In this case, the gas barrier is separately subjected to a dispersion treatment in which cationic metal atoms and the like between the layers of the component D are ionized and eluted in water to cause swelling and cleavage, and then the water is replaced with another organic solvent. A completely non-aqueous solvent system can be realized as a sex coating agent.
In the non-aqueous solvent system, even an organic solvent having low solubility in water can be used, so that the dryness of the above gas barrier coating agent and the wettability to the base film can be adjusted more widely, as well as additives and indications. There is a possibility that many types of base films can be produced.
Examples of the organic solvent that can be used in the non-aqueous solvent system include, in addition to the organic solvents mentioned above, slow-drying acetate-based solvents such as propyl acetate and butyl acetate.

<Additives>
The gas barrier coating agent of the present invention includes a leveling agent, a defoaming agent, a blocking inhibitor such as wax / silica, a mold release agent such as metal soap and amide, an ultraviolet absorber, an antistatic agent, etc., as required. Can be added.

<Content ratio>
Among these materials used in the gas barrier coating agent of the present invention, the content ratio of the component A and the component B has an excellent gas barrier property and a barrier property from the viewpoint of maintaining a high film cohesive force. When the mass of the component A contained in the coating agent is WA and the mass of the component B contained in the barrier coating agent is WB, WA / WB = 20/80 to 70/30 is preferable. ..
Here, when the WA / WB content ratio is higher than the range of WA / WB = 20/80 to 70/30, the concentration of the carbonyl group crosslinked with the component C is lowered, so that a gas barrier coating agent can be applied. There is a possibility that the cohesive force of the film to be formed and the adhesiveness to the plastic film used as the base material will decrease. Further, when it is used for a laminated composite film, it may not be possible to obtain sufficient laminating strength. On the other hand, if the WA content ratio is low, it may not be possible to obtain good gas barrier properties, particularly good water vapor barrier properties, in the thin film.
The content ratio of the component C is preferably WB / WC = 95/5 to 70/30.
Here, when the WB content ratio is higher than the range of WB / WC = 95/5 to 70/30, the cohesive force of the film obtained by applying the gas barrier coating agent and the plastic film as the base material Adhesiveness may decrease. Further, when it is used for a laminated composite film, it may not be possible to obtain sufficient laminating strength. On the other hand, a low WB content means that the content ratio of the component C is excessive, and there is a possibility that a good gas barrier property, particularly a good water vapor barrier property, cannot be obtained in the thin film.
The content ratio of the component D is preferably (WA + WB) / WD = 95/5 to 70/30 when the mass of the component D contained in the barrier coating agent is WD.
Here, if the content ratio of (WA + WB) is higher than the range of (WA + WB) / WD = 95/5 to 70/30, good gas barrier properties may not be obtained in the thin film. On the other hand, when the content ratio of (WA + WB) is low, the cohesive force of the film obtained by applying the gas barrier coating agent is lowered, the adhesiveness to the plastic film as the base material is lowered, and it is used for the laminated composite film. When it is done, it may not be possible to obtain sufficient laminating strength.

(2) Laminating Method As a method of laminating the gas barrier resin composition layer on the inorganic thin film layer, a coating liquid obtained by dissolving and dispersing each material of the gas barrier resin composition in a solvent is applied to a film having an inorganic thin film layer. A method of coating on an inorganic thin film layer, a method of melting a gas barrier resin composition and extruding it onto the inorganic thin film layer of a film having an inorganic thin film layer for laminating, and a method of separately preparing a film of a gas barrier resin composition. There is a method of adhering the above to the inorganic thin film layer of the film having the inorganic thin film layer with an adhesive or the like. Above all, the coating method is preferable from the viewpoint of simplicity, productivity and the like.

Hereinafter, as a preferable laminating method, a method of applying a coating liquid in which each material of the gas barrier resin composition is dissolved and dispersed in a solvent is applied onto the inorganic thin film layer of the film having the inorganic thin film layer will be described.
As the solvent (solvent) of the gas barrier resin composition, either an aqueous solvent or a non-aqueous solvent capable of dissolving the vinyl alcohol-based polymer resin can be used, but water or a mixed solvent of water and isopropyl alcohol may be used. preferable. As the coating method, conventional materials such as gravure coat, bar coat, die coat, and spray coat can be adopted according to the characteristics of the coating liquid.

(3) Thickness of Gas Barrier Resin Composition Layer The thickness (μm) of the gas barrier resin composition layer is preferably 0.01 to 0.70 μm, more preferably 0.05 to 0.50 μm, and particularly preferably. Is 0.08 to 0.50 μm. If it is less than 0.01 μm, the gas barrier property deteriorates, and if it exceeds 0.70 μm, insufficient drying occurs at the time of coating, problems such as blocking occur in the prepared roll, and the gas barrier resin composition layer becomes brittle and the laminating strength becomes May decrease.

(4) Drying Conditions for Gas Barrier Resin Composition Layer The drying temperature after coating the coating liquid of the gas barrier resin composition is preferably 100 to 200 ° C, more preferably 130 to 200 ° C, still more preferably. The temperature is 150 to 200 ° C. If the temperature is lower than 100 ° C., the coat layer will not be sufficiently dried, and the produced roll will have problems such as blocking. In addition, the gas barrier resin composition layer becomes brittle and the laminate strength decreases.
On the other hand, if the temperature exceeds 200 ° C., the film is heated too much and the base film becomes brittle or shrinks, resulting in poor workability.

(5) Laminating order of gas barrier laminated film In order to exhibit the moisture resistance of the gas barrier laminated film, the base film layer, the inorganic thin film layer, and the gas barrier resin composition layer should be arranged in this order from the high humidity side. is necessary. By arranging the inorganic thin film layer on the high humidity side of the gas barrier resin composition layer having a large humidity dependence, it is possible to prevent the deterioration of the barrier property due to the high humidity of the gas barrier resin composition layer.

The gas barrier property measuring method at this time is as follows.
(6) Water vapor permeability A gas barrier laminated film in which the above-mentioned inorganic thin film layer and gas barrier resin composition layer are laminated is applied to a water vapor permeability measuring device (PERMATRAN-W3 / 33MG MOCON) as a base film of the gas barrier laminated film. The water vapor permeability was measured in an atmosphere of a temperature of 40 ° C. and a humidity of 90% RH according to the JIS K7126 B method. The humidity control to the gas barrier laminated film was carried out for 4 hours in a direction in which water vapor permeated from the film base material side to the gas barrier resin composition layer side.

The gas barrier laminated film of the present invention can be used for various purposes including food packaging applications, and further, a heat seal layer, a printing layer, another resin film, and an adhesive for adhering these layers. It can be laminated with other materials such as layers. At the time of laminating, known means such as a method of directly melt-extruding and laminating on the gas barrier laminated film of the present invention, a method of coating, and a method of laminating films directly or via an adhesive may be adopted. I can.
Further, when high gas barrier property is required, two or more gas barrier laminated films of the present invention can be laminated. Further, the inorganic vapor deposition layer may be further provided on the gas barrier resin composition layer, or the gas barrier resin composition layer may be further provided on the inorganic vapor deposition layer, and the layers may be alternately laminated. Further, an inorganic vapor deposition layer, a gas barrier resin composition layer, an anchor layer and the like may be provided on both sides of the base film.
For example, when used as a lid material or packaging bag for confectionery, daily necessities, electronic parts, pharmaceuticals, etc. that require moisture resistance, a heat seal layer such as polyethylene or polypropylene should be provided on the gas barrier resin composition layer. Is preferable. Further, another resin film may be laminated between the gas barrier resin layer and the heat seal layer. As another resin film, a resin film as mentioned as a base film can be used. At the time of laminating these, they can be laminated via an adhesive.
In particular, it is preferable to install a material that adsorbs moisture, such as a desiccant, inside the container or packaging bag.

The gas barrier laminated film of the present invention is used for a packaging bag that protects the contents from external moisture such that the base film, the inorganic thin film layer, and the gas barrier resin composition layer are arranged in this order from the outside where the humidity becomes high. Is particularly effective.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" means "% by mass" and "part" means "part by mass". The methods for evaluating physical properties in the following examples and comparative examples are as follows.

(1) Blocking resistance evaluation-1
The peeling sound of the film when the gas barrier laminated film roll with a width of 1020 mm and a winding length of 4000 m obtained in Examples and Comparative Examples was wound with a slitter (NS SLITTER FN105E type manufactured by Nishimura Seisakusho) at a line speed of 100 m / min. I checked the running condition of the film.
(2) Blocking resistance evaluation-2
The coated surface of the gas barrier laminated film obtained in Examples and Comparative Examples was subjected to the following test conditions (rubbing jig weight 500 g, jig set gauze type I, solvent water used) with a rubbing tester (rubbing tester manufactured by NISHIDA). , Rotation axis rotation speed 13.60 rpm, rubbing jig reciprocating number 8 times) Perform a rubbing test evaluation, measure the rubbing width and length with a scale, and the width (mm) x vertical width (mm) of the peeled surface. The area (mm ² ) was calculated and evaluated in mm).
(3) Water Vapor Permeability of Gas Barrier Laminated Film The gas barrier laminated film obtained in Examples and Comparative Examples was used in a water vapor permeability measuring device (PERMATRAN-W3 / 33MG MOCON) to cover the base film of the gas barrier laminated film. The surface was installed so that the humidity control gas of the measuring instrument flowed, and the water vapor transmission rate was measured in an atmosphere of a temperature of 40 ° C. and a humidity of 90% RH according to the JIS K7126 B method. The humidity control to the gas barrier laminated film was carried out for 4 hours in a direction in which water vapor permeated from the film base material layer side to the gas barrier resin composition layer side.
(4) Oxygen Permeability of Gas Barrier Laminated Film The gas barrier laminated film obtained in Examples and Comparative Examples was applied to an oxygen permeability measuring device (OX-TRAN 2/20 MOCON) as a base film for the gas barrier laminated film. The oxygen permeability was measured in an atmosphere of a temperature of 23 ° C. and a humidity of 65% RH according to the JIS K7126-2 method. Humidity control on the gas barrier laminated film was carried out for 4 hours at a humidity of 65% RH on both the gas barrier coat layer side and the film substrate side.

(Preparation of coating liquid for forming a gas barrier resin composition layer)
The preparation of the coating liquid for forming the gas barrier resin composition layer used in Examples and Comparative Examples will be described below.

<Vinyl alcohol-based copolymer resin having the structural unit of the above formula 1 in the molecule (component A or less, abbreviated as component A), vinyl alcohol-based polymer resin having a carbonyl group in the molecule (component B or less, component B). (Abbreviated as), mixed solution of inorganic layered compound (hereinafter abbreviated as component D) (hereinafter abbreviated as mixed solution)>
Ingredient A / Ingredient B / Ingredient D are mixed with an aqueous mixed solvent mainly containing purified water / IPA (isopropanol), and the mixture is prepared so that the solid content concentration is 5.3% by mass.

The mixed solution used in the examples will be described below.
Component A represents a polyvinyl alcohol-based copolymer resin having a structural unit represented by the formula 1 in the molecule, component B represents a polyvinyl alcohol-based (co) polymer resin represented by the formula 6, and component D represents a polyvinyl alcohol-based (co) polymer resin. Indicates montmorillonite.
<Mixed solution 1>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 18/72/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID20)
<Mixed solution 2>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 27/63/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID30)
<Mixed solution 3>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 36/54/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID40)
<Mixed solution 4>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 0/90/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID00)
<Mixed solution 5>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 45/45/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID50)
<Mixed solution 6>
The composition ratio of the solid content of the mixed solution is mixed at a ratio of component A / component B / component D = 63/27/10 and mixed so that the solid content concentration is 5.3% by mass (manufactured by Sakata Inx Corporation, product name: Eco). Stage TY10ID70)

<Preparation of polyvinyl alcohol solution>
Completely saponified polyvinyl alcohol resin (manufactured by Kuraray, trade name: Kuraray Poval PVA105, saponification degree 98.0-99.0 mol%, average degree of polymerization 500), hereinafter abbreviated as PVA) in 90 parts by mass of purified water. The portion was added, and the mixture was heated to 80 ° C. with stirring, and then stirred for about 2 hours. Then, the mixture was cooled to room temperature to obtain a substantially transparent polyvinyl alcohol solution having a solid content of 10%.

<Preparation of inorganic layered compound dispersion>
4 parts by mass of montmorillonite (trade name: Kunipia F, manufactured by Kunimine Kogyo Co., Ltd.), which is an inorganic layered compound, was added to 96 parts by mass of purified water with stirring, and sufficiently dispersed by a high-pressure disperser at a pressure of 50 MPa. .. Then, the mixture was kept warm at 40 ° C. for 1 day to obtain an inorganic layered compound dispersion having a solid content of 4%.

<Preparation of mixed solution of polyvinyl alcohol and inorganic layered compound>
The polyvinyl alcohol solution obtained above and the inorganic layered compound dispersion are mixed with a water-based mixed solvent mainly containing purified water / IPA, and the composition ratio of the solid content is mixed at a ratio of polyvinyl alcohol / inorganic layered compound = 90/10. , The mixture was prepared so as to have a solid content concentration of 5.3% by mass.

<Crosslinking agent>
Hydrazine-based cross-linking agent (component C) (Sakata Inx Corporation, trade name Ecostage cross-linking agent, solid content of about 5%)
Titanium Lactate (manufactured by Matsumoto Pharmaceutical Co., Ltd., trade name Olga Chix TC-310, solid content about 45%)

<Mixed solvent A>
Purified water and IPA were mixed at a ratio of 1: 1.

<Preparation of coating liquid for forming the gas barrier resin composition layer of Examples 1 and 6>
81.60 parts by mass of the mixed solution 1 is added to 14.90 parts by mass of the mixed solvent A, and after sufficient stirring and mixing, 3.50 parts by mass of the ecostage cross-linking agent is added, and the mixture is sufficiently stirred and mixed to solidify. A coating solution for forming a gas barrier resin composition layer of Example 1 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming the gas barrier resin composition layer of Example 2>
81.60 parts by mass of the mixed solution 2 is added to 14.90 parts by mass of the mixed solvent A, and after sufficient stirring and mixing, 3.50 parts by mass of the ecostage cross-linking agent is added, and the mixture is sufficiently stirred and mixed to solidify. A coating solution for forming a gas barrier resin composition layer of Example 2 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming a gas barrier resin composition layer of Example 3>
81.60 parts by mass of the mixed solution 3 is added to 14.90 parts by mass of the mixed solvent A, and after sufficient stirring and mixing, 3.50 parts by mass of the ecostage cross-linking agent is added, and the mixture is sufficiently stirred and mixed to solidify. A coating solution for forming a gas barrier resin composition layer of Example 3 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming the gas barrier resin composition layer of Example 4>
81.60 parts by mass of the mixed solution 5 is added to 14.90 parts by mass of the mixed solvent A, and the mixture is sufficiently stirred and mixed. A coating solution for forming a gas barrier resin composition layer of Comparative Example 1 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming the gas barrier resin composition layer of Example 5>
81.60 parts by mass of the mixed solution 6 is added to 14.90 parts by mass of the mixed solvent A, and after sufficient stirring and mixing, 3.50 parts by mass of the ecostage cross-linking agent is added, and the mixture is sufficiently stirred and mixed to solidify. A coating solution for forming a gas barrier resin composition layer of Comparative Example 1 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming the gas barrier resin composition layer of Comparative Examples 1 and 2>
81.60 parts by mass of the mixed solution 4 is added to 14.90 parts by mass of the mixed solvent A, and after sufficient stirring and mixing, 3.50 parts by mass of the ecostage cross-linking agent is added, and the mixture is sufficiently stirred and mixed to solidify. A coating solution for forming a gas barrier resin composition layer of Comparative Example 2 having a fraction of about 4.5% was obtained.

<Preparation of coating liquid for forming a gas barrier resin composition layer of Comparative Example 3>
77.10 parts by mass of a mixed solution of polyvinyl alcohol and an inorganic layered compound is added to 22.00 parts by mass of the mixed solvent A, and the mixture is sufficiently stirred and mixed, and then titanium lactate (manufactured by Matsumoto Pharmaceutical Co., Ltd., trade name Organtics TC). -310) was added in an amount of 0.90 parts by mass, and the mixture was sufficiently stirred and mixed to obtain a coating solution for forming a gas barrier resin composition layer of Comparative Example 4 having a solid content of about 4.5%.

(Gas barrier laminated films of Examples 1 to 5 and Comparative Examples 1 and 2)
The gas barrier resin compositions of Examples 1 to 5 and Comparative Examples 1 and 2 were coated on the inorganic thin film layer of a biaxially stretched polyester film having a thickness of 12 μm having an inorganic thin film layer of aluminum oxide of 10 nm by a gravure roll coating method. , A gas barrier resin layer was formed by drying at 180 ° C. to prepare a gas barrier laminated film.
The thickness of the gas barrier resin layer was about 0.25 μm after drying.

(Gas barrier laminated film of Example 6 and Comparative Example 3)
Example 6; The gas barrier resin composition of Comparative Example 3 was applied by a gravure roll coating method and dried at 180 ° C. to form a gas barrier resin layer to prepare a gas barrier laminated film.
The thickness of the gas barrier resin layer was about 0.25 μm after drying.

The above results are shown in Table 1.

From the above results, in Comparative Examples 1 and 2, since the component A was not contained in the gas barrier resin composition, the water vapor transmission rate was large and the moisture resistance was inferior. Further, in Comparative Example 3, since the components A to C were not contained, the blocking resistance was inferior.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to obtain a gas barrier laminated film having an interlayer adhesive force for exhibiting the minimum necessary laminating strength as a packaging bag while having a high gas barrier property against oxygen, water vapor and the like. In addition, it is possible to stably produce a highly practical gas barrier laminated film suitable for moisture-proof packaging applications for protecting the contents from external humidity. The gas barrier film of the present invention can be widely used for packaging of confectionery, daily necessities, electronic parts, pharmaceuticals, etc. and industrial applications such as vacuum heat insulating materials, which require moisture resistance to protect from external moisture. can.

Claims (4)

A gas barrier laminated film in which an inorganic thin film layer and a gas barrier resin composition layer are laminated in this order on at least one surface of the base film, and the gas barrier resin composition layer is represented by the following formula 3. Polyvinyl alcohol-based copolymer resin (component A), polyvinyl alcohol-based (co) polymer resin represented by the following formula 6 (component B), hydrazine-based cross-linking agent (component C), and inorganic layered compound (component D). A gas barrier laminated film, which is a crosslinked product layer of a composition containing.

(However, R ₁ and R ₂ have the same definition as above, and X represents a structural unit derived from the molecular structure of the radically polymerizable monomer used as a copolymerization component and does not correspond to the other two structural units. m and n represent the average number of each structural unit per molecule, l + m + n = 300 to 4000, l / (l + m + n) = 0.001 to 0.2, m / (l + m + n) = 0.8 to 0. .99, n / (l + m + n) = 0 to 0.1 is satisfied.)

(However, R ₆ is a hydrogen or a methyl group. Further, Y is derived from the molecular structure of the radically polymerizable monomer used as a copolymerization component and represents a structural unit that does not correspond to the other three structural units. O + p + q + r. Is 300 to 4000, and (o + p) / (o + p + q + r) = 0.001 to 0.25, q / (o + p + q + r) = 0.75 to 0.999, and r / (o + p + q + r) = 0 to 0.2. Satisfy the relationship.) The gas barrier laminated film according to claim 1, wherein the gas barrier resin composition layer satisfies the following conditions 1 to 3.
Condition 1: When the mass of the component A contained in the barrier coating agent forming the gas barrier resin composition layer is WA and the mass of the component B contained in the barrier coating agent is WB, WA. / WB = 20/80 to 70/30.
Condition 2: When the mass of the component B is WB and the mass of the component C is WC, WB / WC = 95/5 to 70/30.
Condition 3: Further, when the mass of the component D contained in the barrier coating agent is WD, (WA + WB) / WD = 95/5 to 70/30. The gas barrier laminated film according to claim 1 or 2, wherein the inorganic thin film layer contains at least one kind of inorganic oxide containing silicon oxide and / or aluminum oxide. A gas-barrier packaging bag using the gas-barrier laminated film according to any one of claims 1 to 3, wherein the base film layer, the inorganic thin film layer, and the gas-barrier resin composition layer are in this order from the outside of the bag. Placed gas barrier packaging bag.