JP2016193509A - Gas-barrier packaging material and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-barrier packaging material that exhibits high oxygen barrier properties and water vapor barrier properties even if an inorganic vapor-deposited layer is not disposed.SOLUTION: A gas-barrier packaging material 10 includes a barrier layer 3. When an infrared absorption spectrum of the barrier layer 3 is measured, a ratio (α/β) of a maximum peak height (β) of light absorption within a range of 1490-1659 cmand a maximum peak height (α) of light absorption within a range of 1300-1490 cmis 0.6 or more, a ratio (β/γ) of a maximum peak height (γ) of light absorption within a range of 1660-1750 cmand the maximum peak height (β) is 1.0 or more, and the ammonia content is 2000 μg or less per 100 cm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas barrier packaging material and a method for producing the same.

  For packaging materials used for packaging foods, pharmaceuticals, etc., it is required to prevent the contents from being altered. For example, food packaging materials are required to be able to suppress oxidation and alteration of proteins, fats and oils, and to maintain flavor and freshness. In addition, for pharmaceutical packaging materials that require handling in a sterile state, it is required to suppress the alteration of the active ingredients in the contents and to retain the efficacy. Such alteration of the contents is mainly caused by oxygen or water vapor that permeates the packaging material or other gases that react with the contents. For this reason, packaging materials used for packaging foods and pharmaceuticals are required to have properties (gas barrier properties) that do not allow gas such as oxygen and water vapor to permeate.

In response to such a demand, a gas barrier film composed of a polymer (gas barrier polymer) that has been relatively high in gas barrier properties, and a laminate (laminated film) using the same as a film base material have been conventionally used. It is used.
Conventionally, as a gas barrier polymer, a polymer containing a highly hydrophilic high hydrogen bonding group in the molecule, represented by poly (meth) acrylic acid or polyvinyl alcohol, has been used. Packaging materials made of these polymers exhibit very good oxygen barrier properties under dry conditions. However, the packaging material made of these polymers has a problem that the oxygen barrier property is greatly lowered due to its hydrophilicity under high humidity conditions, and a problem of poor resistance to humidity and hot water.

In order to solve these problems, a polycarboxylic acid-based polymer layer and a polyvalent metal compound-containing layer are laminated adjacent to each other on a base material and reacted between these two layers, thereby producing a polycarboxylic acid-based polymer layer. It is known that a polyvalent metal salt of a polymer is produced to form a gas barrier packaging material (for example, see Patent Documents 1 to 3). The gas barrier packaging material thus obtained is known to have a high oxygen barrier property even under high humidity.
However, the layer containing the polyvalent metal salt of the polycarboxylic acid polymer formed in this way is excellent in oxygen barrier property but low in water vapor barrier property. In addition, since the polycarboxylic acid polymer and the polyvalent metal compound easily react in an aqueous solution to form a non-uniform precipitate, which makes coating difficult. A carboxylic acid polymer and a polyvalent metal compound are blended in different coating solutions. Therefore, a plurality of types of coating liquids are necessary, and it is necessary to perform the coating a plurality of times, which is troublesome. In order to develop gas barrier properties, it is necessary to react a polycarboxylic acid polymer present in different layers with a polyvalent metal compound to form a polyvalent metal salt of the polycarboxylic acid polymer. After coating, it must be retorted or exposed to a humid environment for a long time.

In the aforementioned Patent Document 1, a method using a solution of a mixture containing a polycarboxylic acid polymer, a polyvalent metal compound, a volatile base and a solvent is also proposed. In this solution, the polyvalent metal compound and the volatile base form a complex, the reaction between the polycarboxylic acid polymer and the polyvalent metal compound is suppressed, and a uniform solution is obtained. When such a solution is applied and dried, the reaction between the polycarboxylic acid polymer and the polyvalent metal compound proceeds by removing the volatile base or acid from the coating film. Therefore, the layer containing the polyvalent metal salt of the polycarboxylic acid polymer can be formed with a single liquid.
However, even when formed in this manner, the water vapor barrier property of the layer containing the polyvalent metal salt of the polycarboxylic acid polymer is low as described above.
Therefore, when used for applications requiring water vapor barrier properties, it is necessary to provide water vapor barrier properties by providing an inorganic vapor deposition layer in addition to the layer containing the polyvalent metal salt of the polycarboxylic acid polymer. There was time and cost.

Japanese Patent No. 4373797 Japanese Patent No. 5012895 JP 2005-125893 A

  The present invention has been made in view of the above circumstances, and provides a gas barrier packaging material that exhibits high oxygen barrier properties and water vapor barrier properties even when an inorganic vapor deposition layer is not provided, and a method for producing the same. Objective.

The present invention has the following aspects.
[1] A barrier layer (B) is provided,
The maximum peak height (β) of absorbance in the range of 1490 to 1659 cm ⁻¹ and the maximum peak height of absorbance in the range of 1300 to 1490 cm ⁻¹ when the infrared absorption spectrum of the barrier layer (B) is measured. The ratio (α / β) to the thickness (α) is 0.6 or more, and the maximum peak height (γ) of the absorbance within the range of 1660 to 1750 cm ⁻¹ , the maximum peak height (β) Ratio (β / γ) is 1.0 or more,
A gas barrier packaging material, wherein the ammonia content measured by gas chromatography per 100 cm ² is 2000 μg or less.
[2] The gas barrier packaging material according to [1], wherein the barrier layer (B) contains a polycarboxylic acid polymer.
[3] The gas barrier packaging material according to [1] or [2], wherein the barrier layer (B) contains a polyvalent metal.
[4] The oxygen permeability measured under conditions of a temperature of 30 ° C. and a relative humidity of 70% is 5 cm ³ (STP) / (m ² · day · MPa) or less, and a temperature of 40 ° C. and a relative humidity of 90%. The gas barrier packaging material according to any one of [1] to [3], wherein the water vapor permeability measured is 1 g / (m ² · day) or less.
[5] A method for producing a gas barrier packaging material comprising a barrier layer (B),
Drying a coating film comprising a gas barrier coating solution containing a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), and a solvent. And forming a barrier layer (B),
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to the number of moles in terms of polyvalent metal of the amphoteric polyvalent metal compound (b2),
The carbonic acid component equivalent content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal,
The method for producing a gas barrier packaging material, wherein the coating film is dried so that the ammonia content measured by gas chromatography per 100 cm ² of the obtained gas barrier packaging material is 2000 μg or less. .
[6] The method for producing a gas barrier packaging material according to [5], wherein the coating film is dried by heat treatment at 160 to 250 ° C. for 30 seconds to 10 minutes.

The gas barrier packaging material of the present invention exhibits high oxygen barrier properties and water vapor barrier properties even when an inorganic vapor deposition layer is not provided.
According to the method for producing a gas barrier packaging material of the present invention, a gas barrier packaging material exhibiting high oxygen barrier properties and water vapor barrier properties can be produced even when an inorganic vapor deposition layer is not provided.

It is sectional drawing which shows typically the gas-barrier packaging material of 1st Embodiment of this invention. It is sectional drawing which shows typically the gas-barrier packaging material of 2nd Embodiment of this invention. It is sectional drawing which shows typically the gas-barrier packaging material of 3rd Embodiment of this invention.

Hereinafter, the gas barrier packaging material of the present invention will be described with reference to the accompanying drawings.
The following embodiments are specifically described for better understanding of 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 gas barrier packaging material according to a first embodiment of the present invention.
The gas barrier packaging material 10 of this embodiment includes a base material 1 and a barrier layer 3 (barrier layer (B)) laminated on one surface of the base material 1.

(Base material)
Examples of the material constituting the substrate 1 include plastics, papers, and rubbers. Among these, plastics are preferable from the viewpoint of adhesion between the substrate 1 and the layer formed on the substrate 1.

  Examples of plastics include low-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, poly-4-methylpentene, polyolefins such as cyclic polyolefin, copolymers of the above-mentioned polyolefin polymers, Acid-modified products of the above-mentioned polyolefin polymers; vinyl acetate copolymers such as polyvinyl acetate, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol; polyethylene terephthalate, polybutylene terephthalate Polyester polymers such as polyethylene naphthalate, polyε-caprolactone, polyhydroxybutyrate, polyhydroxyvalylate, and the like, copolymers of the above polyester polymers; nylon 6, nylon 66, nylon 12, nylon 6- Polyamide polymers such as Iron 66 copolymer, nylon 6-nylon 12 copolymer, metaxylene adipamide / nylon 6 copolymer, copolymers of the above polyamide polymers; polyethylene glycol, polyether sulfone Polyether polymers such as polyphenylene sulfide and polyphenylene oxide; chlorine polymers or fluorine polymers such as polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, the above-mentioned chlorine polymers or fluorine polymers Copolymers of polymers; acrylic polymers such as polymethyl acrylate, polyethyl acrylate, polymethyl methacrylate, polyethyl methacrylate, polyacrylonitrile, copolymers of the above acrylic polymers; polyimide polymers, the above Of polyimide polymer Copolymer: Alkyd resin, melamine resin, acrylic resin, nitrified cotton, urethane resin, unsaturated polyester resin, phenol resin, amino resin, fluororesin, epoxy resin used for paint, etc .; cellulose, starch, pullulan, chitin Natural polymer compounds such as chitosan, glucomannan, agarose, gelatin, and mixtures thereof.

  As the base material 1, a thin film made of an inorganic compound or a metal compound such as silicon oxide, aluminum oxide, aluminum, or silicon nitride is formed on the surface of the plastic by vapor deposition, sputtering, or ion plating. It may be used.

  It does not specifically limit as a form of the base material 1, For example, forms, such as a film, a sheet | seat, a bottle, a cup, a tray, a tank, a tube, are mentioned. In the present embodiment, a film or a sheet is preferable from the viewpoint of laminating the barrier layer 3 and the like.

Although the thickness of the base material 1 changes with the uses etc., it is preferable that they are 5 micrometers-5 cm.
In the use of a film or a sheet, the thickness of the substrate 1 is preferably 5 μm to 800 μm, and more preferably 5 μm to 500 μm.
When the thickness of the substrate 1 is within the above range, the workability and productivity in each application are excellent.

  From the viewpoint of adhesion to the layer formed on the substrate 1, the surface of the substrate 1 may be subjected to surface activation treatment such as corona treatment, flame treatment, and plasma treatment.

(Barrier layer)
The barrier layer 3 has a maximum peak height (β) of absorbance in the range of 1490 to 1659 cm ⁻¹ when the infrared absorption spectrum (hereinafter also referred to as “IR spectrum”) of the barrier layer 3 is measured, and 1300 maximum peak height absorbance in the range of ~1490cm ^-1 (α) ratio of (alpha / beta) is not less than 0.6, and the maximum peak absorbance in the range of 1660～1750Cm ^-1 height ( The ratio (β / γ) between γ) and the maximum peak height (β) is 1.0 or more.

  The absorbance when the IR spectrum of the barrier layer 3 is measured is proportional to the amount of chemical species having infrared activity present in the barrier layer 3.

The maximum peak height (α) is the maximum peak height of the absorbance of the IR spectrum of 1400 cm ⁻¹ N—H bending vibration attributed to ammonia forming the complex. Specific examples, N-H deformation vibration attributable to the ammonia forming a polyvalent metal ammine complexes are typically in the infrared wave number range of 1300～1490Cm ^-1, absorption maximum around 1400 cm ^-1 Gives an absorption peak with

The maximum peak height (β) is an IR spectrum of a C═O stretching vibration of 1560 cm ⁻¹ belonging to a carboxyl group (—COO ⁻ ) forming a salt (hereinafter also referred to as “carboxyl salt”). Is the maximum peak height of the absorbance. To give a specific example, in a polycarboxylic acid polymer ionically crosslinked with a polyvalent metal, that is, a polyvalent metal salt of the polycarboxylic acid polymer, it belongs to the carboxyl group forming the salt with the polyvalent metal. C = O stretching vibration is ^usually an infrared wave number range of 1490cm ^-1 ~1659cm -1, giving an absorption peak having an absorption maximum in the vicinity of 1560 cm ^-1.

The maximum peak height (γ) is the maximum peak height of the absorbance of the IR spectrum separated and independent from the maximum peak height (β), and is 1700 cm ⁻¹ C═O attributed to a free carboxyl group (—COOH). It is the maximum peak height of the absorbance of the IR spectrum of stretching vibration. Specific examples, C = O stretching vibration attributable to the free carboxyl groups of the polycarboxylic acid polymer is ^usually in the infrared wave number range of 1660cm ^-1 ~1750cm -1, absorption maximum around 1700 cm ^-1 Gives an absorption peak with

Therefore, the ratio (α / β) between the maximum peak height (β) and the maximum peak height (α) represents the ratio between the carboxyl group salt in the barrier layer 3 and the ammonia forming the complex. It can be used as a scale.
Further, the ratio (β / γ) between the maximum peak height (γ) and the maximum peak height (β) should be used as a measure representing the ratio between the free carboxyl group and the salt of the carboxyl group in the barrier layer 3. Can do.

The ratio (α / β) is 0.6 or more, preferably 0.7 or more.
The ratio (β / γ) is 1.0 or more, preferably 5.0 or more, and more preferably 10.0 or more.
When the ratio (α / β) and the ratio (β / γ) are each equal to or higher than the lower limit value, the barrier layer 3 exhibits high oxygen barrier properties and water vapor barrier properties even under high humidity.
The upper limits of the ratio (α / β) and ratio (β / γ) are not particularly limited.

Since the ratio (α / β) is 0.6 or more and the ratio (β / γ) is 1.0 or more, the barrier layer 3 contains ammonia forming a complex and a salt of a carboxyl group. . That is, an ammine complex and a carboxylic acid salt are included.
As an example, a case where a polyvalent metal ammine complex is included as an ammine complex and a polyvalent metal salt of a polycarboxylic acid is included as a carboxylic acid salt, the ratio (α / β) is 0.6 or more, and the ratio (β / The reason why the barrier layer 3 exhibits the above effect when γ) is 1.0 or more will be described.
The polyvalent metal ammine complex is uniformly distributed in the barrier layer 3 to produce a maze effect and suppress the transmission of oxygen and water vapor. Since the polycarboxylic acid polymer has a carboxyl group, it has a small free volume, suppresses the permeation of oxygen, and firmly fixes the polyvalent metal ammine complex.
When the polycarboxylic acid polymer contains a free carboxyl group, the free carboxyl group reacts with the polyvalent metal ammine complex to form a carboxyl group (polyvalent metal salt of the carboxyl group) that forms a salt with the polyvalent metal. On the other hand, the polyvalent metal ammine complex decreases. That is, the ratio (α / β) is reduced and the maze effect is reduced. Further, when the ratio (β / γ) is less than 1.0, that is, when the polycarboxylic acid polymer contains free carboxyl groups at a certain ratio or more, the molecular chain of the polycarboxylic acid polymer under high humidity Easily spreads, the oxygen barrier property of itself decreases, and the effect of fixing the polyvalent metal ammine complex also decreases.
If the ratio (α / β) and the ratio (β / γ) are each equal to or higher than the lower limit value, almost all the carboxyl groups of the polycarboxylic acid polymer are ion-crosslinked by a polyvalent metal salt, that is, a polyvalent metal. In this state, there is little or no reaction with the polyvalent metal ammine complex. Further, such polycarboxylic acid-based polymers are difficult to expand molecular chains even under high humidity and firmly fix the polyvalent metal ammine complex, so that permeation of oxygen and water vapor is sufficiently suppressed even under high humidity. In addition, the oxygen barrier property due to the polycarboxylic acid-based polymer is not easily lowered. Therefore, it is considered that the barrier layer 3 exhibits a high oxygen barrier property and a water vapor barrier property over a wide range from a low humidity region to a high humidity region.
The ammine complex is not limited to the polyvalent metal ammine complex as long as it exhibits the maze effect as described above. In addition, the carboxylic acid salt is not limited to the polyvalent metal salt of the polycarboxylic acid polymer as long as it exhibits the above-described fixing effect of the ammine complex.

The ratio (α / β) between the maximum peak height (β) and the maximum peak height (α), and the ratio (β / γ) between the maximum peak height (γ) and the maximum peak height (β) are the IR spectrum of the sample was measured, the maximum peak height absorbance in the range of 1300～1490Cm ^-1 and ^(alpha), the maximum peak height in absorbance in the range of 1660cm ^-1 ~1750cm -1 and (gamma), 1490Cm ^-1 maximum peak absorbance in the range of ～1659Cm ^-1 height and (beta) can be determined by measuring.
The IR spectrum can be measured by using a known method such as a transmission method, an ATR method (attenuated total reflection method), a KBr pellet method, a diffuse reflection method, or a photoacoustic method (PAS method). For example, as a Fourier transform infrared spectroscopy (FT-IT) analyzer, an IR image manufactured by Perkin Elmer can be used to measure an IR spectrum by the ATR method. For the IR spectrum measurement method using FT-IR, reference can be made to, for example, “The Basics and Practice of FT-IR” by Mitsuo Tasumi.
The IR spectrum is preferably measured by the transmission method or the ATR method from the viewpoint of simplicity.
A typical IR spectrum measurement method includes a method of measuring the surface of the barrier layer 3 by the ATR method. As measurement conditions of the IR spectrum at this time, from the viewpoint of penetration depth, Ge (germanium) is used, and the measurement condition is an incident angle of 45 degrees, a resolution of 4 cm ⁻¹ , and an integration count of 10.
When the IR spectrum is measured by the transmission method, the IR spectrum in a state where the barrier layer 3 is removed from the gas barrier packaging material 10 and the IR spectrum of the gas barrier packaging material 10 are compared. In this case, it is preferable to use the IR spectrum in a state where the barrier layer 3 is removed from the gas barrier packaging material 10 as the background. The barrier layer 3 can be removed from the gas barrier packaging material 10 with a strong acid or a strong base, such as hydrochloric acid or a sodium hydroxide aqueous solution.
In IR spectrum, the maximum peak height in absorbance is a value obtained by a line connecting a straight line and the absorbance of the absorbance and 1900 cm ^-1 of 900 cm ^-1 baseline.

From the ratio (β / γ) of the maximum peak height (γ) and the maximum peak height (β), the ionization degree of the barrier layer 3 is obtained.
The ionization degree of the barrier layer 3 is preferably 1.0 or more, and more preferably 5.0 or more. If the degree of ionization is at least the lower limit, higher oxygen barrier properties and water vapor barrier properties can be obtained.
The degree of ionization is defined by the following formula (1).
(Degree of ionization) = Y / X (1)
(In the formula, X is the number of moles of carbonyl carbon attributed to all the carboxyl groups in 1 g of the barrier layer 3. Y is the mole of carbonyl carbon attributed to the salt of the carboxyl group in 1 g of the barrier layer 3) Number.)

The degree of ionization is the ratio of the number of carboxyl group salts to all the carboxyl groups in the barrier layer 3, and can be determined as a stricter ratio of chemical species than the ratio (β / γ).
All carboxyl groups include the aforementioned polyvalent metal salts and monovalent metal salts (alkali metal salts such as sodium salts and potassium salts) as carboxyl group salts.
In order to obtain the degree of ionization from the measurement result of the IR spectrum, a calibration curve prepared in advance is used. The calibration curve can be created by the method described in Japanese Patent No. 4373797.
The IR spectrum is mainly derived from the chemical structure of the carboxyl group, and is less affected by the metal species of the salt. For example, when a metal compound composed of a monovalent metal is added to the gas barrier coating liquid used in the production method described later within a range that does not impair the gas barrier properties, the C═O stretching attributed to the polyvalent metal salt of the carboxyl group vibration, C = O stretching vibration attributable to the monovalent metal salt of a carboxyl group ^together, an infrared wave number range of 1490cm ^-1 ~1659cm -1, giving an absorption peak having an absorption maximum in the vicinity of 1560 cm ^-1.

  In the barrier layer 3, the carboxyl group is preferably derived from a polycarboxylic acid polymer. That is, it is preferable that the barrier layer 3 contains a polycarboxylic acid polymer. If the carboxyl group is derived from a polycarboxylic acid-based polymer, higher oxygen barrier properties and water vapor barrier properties can be obtained than when other carboxylic acids are used.

The barrier layer 3 preferably contains a polyvalent metal. The polyvalent metal forms a polyvalent metal salt of a carboxyl group. In addition, a polyvalent metal ammine complex is formed. By containing the polyvalent metal, the oxygen barrier property and the water vapor barrier property under high humidity are higher than in the case where the polyvalent metal is not contained.
The metal species present in the barrier layer 3 can be confirmed by ICP (high frequency inductively coupled plasma) emission spectroscopic analysis, EDX (energy dispersive X-ray) spectroscopy, or the like.

Examples of the barrier layer 3 include a layer formed by drying a coating film made of the following gas barrier coating solution.
Gas barrier coating solution: containing a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), and a solvent,
The content of the amphoteric polyvalent metal compound (b2) is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to the number of moles in terms of polyvalent metal of the amphoteric polyvalent metal compound (b2),
The carbonic acid component-containing content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal.
The gas barrier coating solution and the method of forming the barrier layer 3 using the gas barrier coating solution will be described in detail later.

The thickness of the barrier layer 3 is not particularly limited, but is preferably 0.001 μm to 1 mm, more preferably 0.01 μm to 100 μm, and still more preferably 0.1 μm to 10 μm.
If the thickness of the barrier layer 3 is not less than the lower limit of the above range, the barrier layer 3 tends to be a uniform film. If the barrier layer 3 is a uniform film, adhesion to a layer adjacent to the barrier layer 3 is excellent.
If the thickness of the barrier layer 3 is less than or equal to the upper limit of the above range, ionic cross-linking with a polyvalent metal is quickly formed when the barrier layer 3 is formed, and sufficient oxygen barrier properties and water vapor barrier properties are exhibited in a short time. Cheap.

(Ammonia content)
The gas barrier packaging material 10 has an ammonia content measured by gas chromatography per 100 cm ² (hereinafter also referred to as “GC”) of 2000 μg or less, preferably 1000 μg or less, and more preferably 800 μg or less.
The ammonia content measured by GC is the content of ammonia (NH ₃ ) not forming a complex.
If the ammonia content is less than or equal to the upper limit, the ammonia content per 100 cm ^{2 of} the barrier layer 3 is also 2000 μg or less, and the barrier layer 3 exhibits high oxygen barrier properties and water vapor barrier properties. In the presence of ammonia, the progress of ionic crosslinking by the polyvalent metal of the polycarboxylic acid polymer is inhibited. If the ammonia content is less than or equal to the above upper limit value, it is considered that ion crosslinking with a polyvalent metal of the polycarboxylic acid polymer has sufficiently progressed, and that the above effect can be obtained.
In the present embodiment, the ammonia content per 100 cm ² of the gas barrier packaging material 10 is equal to the ammonia content per 100 cm ^{2 of the} barrier layer 3. If gas barrier packaging material comprises a plurality of barrier layers 3 is the sum of the plurality of barrier layers 3 ammonia content per each 100 cm ² is an ammonia content per 100 cm ² of the gas barrier packaging material 10.

(Oxygen permeability)
The gas barrier packaging material 10 preferably has an oxygen permeability measured under conditions of a temperature of 30 ° C. and a relative humidity of 70% of 5 cm ³ (STP) / (m ² · day · MPa) or less, preferably 1 cm ³ ( STP) / (m ² · day · MPa) or less is more preferable.

(Water vapor permeability)
The gas barrier packaging material 10 preferably has a water vapor permeability measured under conditions of a temperature of 40 ° C. and a relative humidity of 90% of 1 g / (m ² · day) or less, and 0.5 g / (m ² · day). The following is more preferable.

(Method for producing gas barrier packaging material)
The gas barrier packaging material 10 can be manufactured, for example, by the following manufacturing method (I).
Production method (I):
On one surface of the substrate 1, a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), and a solvent are included. Applying a gas barrier coating solution, forming a coating film made of the gas barrier coating solution, and drying the coating film to form the barrier layer 3 (hereinafter also referred to as “step (α1)”). Including
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to the number of moles in terms of polyvalent metal of the amphoteric polyvalent metal compound (b2),
The carbonic acid component equivalent content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal,
The method for producing a gas barrier packaging material, wherein the coating film is dried so that an ammonia content measured by GC per 100 cm ² of the obtained gas barrier packaging material is 2000 µg or less.

In the gas barrier coating solution, a part of ammonia forms a complex (polyvalent metal ammine complex) with the amphoteric polyvalent metal compound. The polyvalent metal ammine complex may form a polyvalent metal ammine complex salt of a polycarboxylic acid polymer.
Since the amphoteric polyvalent metal compound forms a polyvalent metal ammine complex, the reaction between the amphoteric polyvalent metal compound and the polycarboxylic acid-based polymer is suppressed, and the coatable state is maintained.
When the coating film made of the gas barrier coating liquid is dried and the ammonia in the coating film is removed, a polyvalent metal salt of a polycarboxylic acid polymer is formed. Thereby, the layer containing the polyvalent metal salt of the polycarboxylic acid polymer and the polyvalent metal ammine complex is formed as the barrier layer 3. The barrier layer 3 may include a polyvalent metal complex salt of a polycarboxylic acid polymer. Further, the unreacted amphoteric polyvalent metal compound (b2) may be present in the barrier layer 3 in the form of particles or molecules.

[Gas barrier coating solution]
The gas barrier coating liquid contains a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), and a solvent.
The gas barrier coating solution may further contain a silicon compound (b5).
The gas barrier coating liquid further contains other components other than the polycarboxylic acid polymer (b1), the amphoteric polyvalent metal compound (b2), ammonia (b3), the carbonic acid component-containing compound (b4), and the silicon compound (b5). May be included.

<Polycarboxylic acid polymer (b1)>
The “polycarboxylic acid polymer” is a polymer having two or more carboxyl groups in the molecule.
Examples of the polycarboxylic acid polymer (b1) include (co) polymers of ethylenically unsaturated carboxylic acids; copolymers of ethylenically unsaturated carboxylic acids and other ethylenically unsaturated monomers; alginic acid , Acidic polysaccharides having a carboxyl group in the molecule such as carboxymethylcellulose and pectin. These polycarboxylic acid polymers may be used alone or in combination of two or more.

Examples of the ethylenically unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, and crotonic acid.
Examples of other ethylenically unsaturated monomers copolymerizable with the ethylenically unsaturated carboxylic acid include saturated carboxylic acid vinyl esters such as ethylene, propylene, and vinyl acetate, alkyl acrylates, alkyl methacrylates, and alkyl itacos. Nates, vinyl chloride, vinylidene chloride, styrene, acrylamide, acrylonitrile and the like.

The polycarboxylic acid polymer (b1) is at least one selected from the group consisting of acrylic acid, maleic acid, methacrylic acid, itaconic acid, fumaric acid and crotonic acid from the viewpoint of gas barrier properties of the gas barrier packaging material. A polymer containing a structural unit derived from the polymerizable monomer is preferred.
The polymer may be a homopolymer or a copolymer. When it is a copolymer, that is, when other structural units other than the above structural units are included, the other structural units include, for example, an ethylenically unsaturated monomer copolymerizable with an ethylenically unsaturated carboxylic acid. Examples include a polymer.

Among the above, the polycarboxylic acid polymer (b1) is a structural unit derived from at least one polymerizable monomer selected from the group consisting of acrylic acid, maleic acid, methacrylic acid and itaconic acid. Polymers containing are preferred.
In the polymer, the proportion of structural units derived from at least one polymerizable monomer selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid and maleic acid is 80 mol% or more. Preferably, it is 90 mol% or more (however, all the structural units are 100 mol%).

The number average molecular weight of the polycarboxylic acid polymer (b1) is preferably 2,000 to 10,000,000. If the number average molecular weight of the polycarboxylic acid-based polymer (b1) is 2,000 or more, the resulting gas barrier packaging material has better water resistance, and gas barrier properties and transparency are deteriorated by moisture, or whitening occurs. It can never happen. When the number average molecular weight of the polycarboxylic acid polymer (b1) is 10,000,000 or less, the viscosity of the gas barrier coating solution of the present invention does not become too high, and the coating property is hardly impaired.
The number average molecular weight of the polycarboxylic acid polymer (b1) is more preferably 5,000 to 1,000,000 from the viewpoint of water resistance of the obtained gas barrier packaging material.
The number average molecular weight of the polycarboxylic acid polymer (b1) is a number average molecular weight in terms of polystyrene determined by gel permeation chromatography (GPC).
A polycarboxylic acid type polymer (b1) may be used individually by 1 type, and may use 2 or more types together.

<Amphoteric polyvalent metal compound (b2)>
The “amphoteric polyvalent metal compound” means a polyvalent metal compound that reacts with both an acid and a base.
A “polyvalent metal” is a metal having a valence of 2 or more.
Specific examples of the amphoteric polyvalent metal compound (b2) include zinc oxide and copper oxide.
The amphoteric polyvalent metal compound (b2) may be used alone or in combination of two or more.

<Carbonate component-containing compound (b4)>
The carbonic acid component in the carbonic acid component-containing compound (b4) is a generic term for CO ₃ and HCO ₃ .
Examples of the carbonic acid component-containing compound (b4) include carbonates such as normal salts, acidic salts (bicarbonates), basic salts (carbonate hydroxide salts), and carbonic acid.
Examples of the carbonate include alkali metal and alkaline earth metal carbonates, alkali metal and alkaline earth metal hydrogen carbonates, alkali metal and alkaline earth metal ammonium carbonates, and the like. Specific examples of carbonates include ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, sodium carbonate, potassium carbonate, potassium bicarbonate, cesium carbonate, lanthanum carbonate, lithium carbonate, magnesium carbonate, manganese carbonate, nickel carbonate, strontium carbonate, Examples thereof include aminoguanidine carbonate and guanidine carbonate. In addition, anhydrous carbonates, hydrated salts, or mixtures thereof can be used.
Among the above, the carbonic acid component-containing compound (b4) is preferably ammonium carbonate or ammonium hydrogen carbonate because it does not impair gas barrier properties, is easy to handle, and has better liquid stability of the gas barrier coating solution.
A carbonic acid component containing compound (b4) may be used individually by 1 type, and may use 2 or more types together.

<Solvent>
The solvent is not particularly limited, and examples thereof include water, an organic solvent, a mixed solvent of water and an organic solvent, and the like.

The water is preferably purified water, and examples thereof include distilled water and ion exchange water.
As the organic solvent, it is preferable to use at least one organic solvent selected from the group consisting of lower alcohols having 1 to 5 carbon atoms and lower ketones having 3 to 5 carbon atoms.
Specific examples of the organic solvent include methanol, ethanol, propanol, 2-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, acetone, and methyl ethyl ketone.

As a mixed solvent of water and an organic solvent, the above mixed solvent using water or an organic solvent is preferable, and a mixed solvent of water and a lower alcohol having 1 to 5 carbon atoms is more preferable.
As the mixed solvent, a solvent having a water ratio of 20% to 95% by weight and an organic solvent ratio of 80% to 5% by weight is typically used (however, water and an organic solvent The total is 100% by mass).

  The solvent is preferably water or a mixed solvent of water and an organic solvent from the viewpoint of solubility of the polycarboxylic acid polymer (b1).

<Silicon compound (b5)>
As the silicon compound (b5), those having a functional group that reacts with a carboxyl group are preferred. Examples of the functional group that reacts with a carboxyl group include a glycidyloxy group and an amino group.
As the silicon compound (b5), at least one silicon compound selected from the group consisting of a silane coupling agent represented by the following formula (5), a hydrolyzate thereof, and a condensate thereof (hereinafter referred to as “silicon compound ( b51) ") is preferred.
In addition, in this specification, what condensed the hydrolyzate of the silane coupling agent represented by Formula (5) is also described as a hydrolysis condensate.
Si (OR) ₃ Z (5)
In the above formula (5), R is an alkyl group having 1 to 6 carbon atoms, Z is an organic group containing a glycidyloxy group or an amino group, and R may be the same or different.

  Specific examples of the silane coupling agent represented by the above formula (5) include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ-amino. Examples thereof include propyltriethoxysilane, and γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltrimethoxysilane are preferable. The silane coupling agent may be used alone or in combination of two or more.

The silicon compound (b51) may be the silane coupling agent itself represented by the above formula (5), a hydrolyzate obtained by hydrolysis of the silane coupling agent, or a condensate thereof. Good.
As a silicon compound (b51), what performed the hydrolysis and condensation reaction of the silane coupling agent represented by the said Formula (5) using the sol-gel method, for example can be used.
When water is added to the silane coupling agent represented by the above formula (5), at least a part of the alkoxy group (OR) of the silane coupling agent is substituted with a hydroxyl group to become a hydrolyzate, and further the hydrolysis By condensing the product, a compound in which silicon atoms (Si) are bonded through oxygen is formed. By repeating this condensation, a hydrolysis condensate is obtained.
In general, the silane coupling agent represented by the above formula (5) easily undergoes hydrolysis, and easily undergoes a condensation reaction in the presence of an acid or an alkali. Therefore, only the silane coupling agent is used. It is rare to exist only in the hydrolyzate or in the condensate thereof. That is, the silicon compound (b51) usually contains a silane coupling agent represented by the above formula (5), a hydrolyzate thereof, and a condensate thereof. The hydrolyzate includes a partial hydrolyzate and a complete hydrolyzate.

<Other ingredients>
Examples of other components include polymers other than the polycarboxylic acid polymer (b1), monovalent metal compounds, inorganic layered compounds (such as montmorillonite), and other various additives.
Examples of the additive include a plasticizer, a resin, a dispersant, a surfactant, a softener, a stabilizer, an antiblocking agent, a film forming agent, an adhesive, and an oxygen absorber.

As a plasticizer, it can select from a well-known plasticizer suitably, for example. Specific examples of the plasticizer include, for example, ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, 1,3-butanediol, 2,3-butanediol, pentamethylene glycol, hexamethylene glycol, diethylene glycol, and triethylene. Examples include glycol, polyethylene glycol, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyethylene oxide, sorbitol, mannitol, dulcitol, erythritol, glycerin, lactic acid, fatty acid, starch, and phthalate. These plasticizers may be used individually by 1 type, or may use 2 or more types together as needed.
Among these plasticizers, polyethylene glycol, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, glycerin, and starch are preferable from the viewpoints of stretchability and gas barrier properties.

<Content of each component>
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all carboxyl groups in the polycarboxylic acid polymer (b1), and 1.0 chemistry. Equivalent to 10.0 chemical equivalents are preferable, and 1.0 to 5.0 chemical equivalents are more preferable.
If the content of the amphoteric polyvalent metal compound (b2) is not less than the lower limit, the ratio (β / γ) becomes not less than the lower limit, and the gas barrier property and moisture resistance of the barrier layer 3 are sufficiently improved.
If content of an amphoteric polyvalent metal compound (b2) is below the said upper limit, the transparency of the barrier layer 3 etc. will be excellent.

The content of ammonia (b3) in the gas barrier coating solution is 4.0 chemical equivalents or more with respect to the number of moles in terms of polyvalent metal of the amphoteric polyvalent metal compound (b2), and 4.0 chemical equivalents or more. 0.0 chemical equivalent or less is preferable, and 4.0 chemical equivalent or more and 10.0 chemical equivalent or less is more preferable.
If the content of ammonia (b3) is not less than the lower limit, the amphoteric polyvalent metal compound (b2) forms a complex with ammonia (b3), and the polycarboxylic acid polymer (b1) and the amphoteric polyvalent metal compound The reaction with (b2) can be suppressed, and the gas barrier coating liquid can maintain a transparent and uniform solution state.
On the other hand, the smaller the ammonia (b3) group content, the better the gas barrier properties when the gas content is less than 2000 μg under less heat conditions when the gas barrier coating solution is applied and dried to form the barrier layer. Can be expressed. In addition, the amount of volatilization of ammonia (b3) is small, and the influence of ammonia (b3) on the work environment such as an irritating odor is reduced.

The carbonic acid component-containing content of the carbonic acid component-containing compound (b4) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal, 1.0 chemical equivalent or more and 10.0 chemical equivalent or less are preferable, and 1.0 chemical equivalent or more and 5.0 chemical equivalent or less are more preferable.
When the amphoteric polyvalent metal compound (b2) and aqueous ammonia are mixed, a polyvalent metal hydroxide is produced. This polyvalent metal hydroxide does not dissolve in water, but when ammonia is further added, a polyvalent metal ammine complex ([Zn (NH ³ ) ₄ ] ²⁺ , Cu (NH ³ ) ₄ ] ²⁺ ) is formed, and water is added. Soluble in At that time, when the carbonic acid component derived from the carbonic acid component-containing compound (b4) is present in the above amount as a counter ion of the polyvalent metal ammine complex that is a cation, precipitation of undissolved matter is difficult to occur, It is easy to obtain a uniform solution.
If the said ratio is below the upper limit of the said range, the barrier layer 3 will be easy to form.

  From the viewpoint of coating suitability, the solvent content is such that the ratio of the total amount of the polycarboxylic acid polymer (b1) and the amphoteric polyvalent metal compound (b2) to the total amount of the gas barrier coating solution is 0.1-50. An amount of mass% is preferred.

When the gas barrier coating liquid contains the silicon compound (b5), the content of the silicon compound (b5) in the gas barrier coating liquid is such that the mass of the polycarboxylic acid polymer (b1) and the mass of the silicon compound (b5) It is preferable that the ratio (polycarboxylic acid polymer: silicon compound) is an amount that falls within the range of 99.5: 0.5 to 40.0: 60.0.
When γ-glycidoxypropyltrimethoxysilane or γ-glycidoxypropyltriethoxysilane is used as the silane coupling agent represented by the above formula (5), the polycarboxylic acid polymer (b1) The ratio of the mass to the mass of the silicon compound (b5) is preferably 99.5: 0.5 to 40.0: 60.0, and preferably 99: 1 to 50.0: 50.0. Particularly preferred.
When γ-aminopropyltrimethoxysilane or γ-aminopropyltriethoxysilane is used as the silane coupling agent represented by the above formula (5), the mass of the polycarboxylic acid polymer (b1) and the silicon compound The ratio of (b5) to the mass is preferably 99: 1 to 40.0: 60.0, and particularly preferably 99.0: 1 to 50.0: 50.0.
However, the mass of the silicon compound (b51) other than the silane coupling agent represented by the above formula (5) is the mass in terms of the silane coupling agent represented by the above formula (5). That is, in the silicon compound (b51), the silane coupling agent represented by the above formula (5), a hydrolyzate thereof, and a condensate thereof are mixed, but the mass of the silicon compound (b51) is the above formula ( It is the value converted into the silane coupling agent represented by 5), that is, the charged amount of the silane coupling agent represented by the above formula (5).

  When the gas barrier coating liquid contains other components, the content of other components in the gas barrier coating liquid is determined by the mass ratio of the polycarboxylic acid polymer (b1) to the other components (polycarboxylic acid weight). The combined (b1): other components) is preferably 70:30 to 99.9: 0.1, and more preferably 80:20 to 98: 2.

The chemical equivalents of the amphoteric polyvalent metal compound (b2) and ammonia (b3) for all the carboxyl groups in the polycarboxylic acid polymer (b1) in the gas barrier coating solution are used for the preparation of the gas barrier coating solution. It can be calculated from the raw materials used. Alternatively, the gas barrier coating liquid may be analyzed by an analysis method such as ICP (High Frequency Inductively Coupled Plasma) emission spectroscopy or gas chromatography.
The chemical equivalent will be described in detail by taking as an example the case where the polycarboxylic acid polymer (b1) is polyacrylic acid and the amphoteric polyvalent metal compound (b2) is zinc oxide.
When the mass of polyacrylic acid is 100 g, the molecular weight of the monomer unit of polyacrylic acid is 72, and since it has one carboxyl group per molecule of monomer, the amount of carboxyl group in 100 g of polyacrylic acid Is 1.39 mol. At this time, 1 equivalent with respect to 100 g of polyacrylic acid is the amount of base that neutralizes 1.39 mol. Therefore, when 2.0 equivalent of zinc oxide is added to 100 g of polyacrylic acid, 1.39 × 2.0 = 2.78 mol of zinc oxide is added to neutralize the carboxyl group. do it.
Since the valence of zinc is divalent and the molecular weight of zinc oxide is 81.41, the mass of 2.0 equivalents of zinc oxide with respect to 100 g of polyacrylic acid is 113 g (1.39 mol).

  The gas barrier coating solution comprises a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), a solvent, and, if necessary, silicon. It can be prepared by mixing the compound (b5) and other components.

[Step (α1)]
In the step (α1), the gas barrier coating liquid is applied on one surface of the substrate 1 to form a coating film, and the coating film is dried to form the barrier layer 3.
The coating method of the gas barrier coating liquid is not particularly limited. For example, casting method, dipping method, roll coating method, gravure coating method, screen printing method, reverse coating method, spray coating method, kit coating method, die coating method. , Metal ring bar coating method, chamber doctor combined coating method, curtain coating method and the like.

The coating film is dried so that the ammonia content per 100 cm ² of the obtained gas barrier packaging material is 2000 μg or less. The preferred ammonia content is the same as described above. By performing drying in this manner, the solvent and ammonia (b3) in the coating film are removed, and a polyvalent metal salt of the polycarboxylic acid polymer (b1) is generated to form the barrier layer 3.
Although it does not specifically limit as a drying method, For example, methods, such as a hot-air drying method, a hot roll contact method, an infrared heating method, a microwave heating method, are mentioned. These drying methods may be performed alone or in combination.
Drying is preferably performed by heat treatment at 160 to 250 ° C. for 30 seconds to 10 minutes in order to easily remove ammonia (b3) and make the ammonia content not more than the above upper limit.
The drying is usually carried out under normal pressure or reduced pressure, and it is preferable to carry out under normal pressure from the viewpoint of facility simplicity.
Drying may be performed in one step, or may be performed in two or more steps by changing the drying conditions. Examples of the case where the drying is performed in two or more stages include a case where drying for removing the solvent is first performed and then drying for removing ammonia is performed. In this case, drying for removing ammonia is preferably performed under the above heat treatment conditions. The drying for removing the solvent may be performed at a lower temperature than the drying for removing ammonia.

Second Embodiment
FIG. 2 is a cross-sectional view schematically showing a gas barrier packaging material according to a second embodiment of the present invention. In the embodiment described below, the same reference numerals are given to the components corresponding to the first embodiment, and detailed description thereof will be omitted.
The gas barrier packaging material 20 of the present embodiment includes a base material 1, an anchor coat layer 5 laminated on one surface of the base material 1, and a barrier layer 3 laminated on the anchor coat layer 5.
The gas barrier packaging material 20 is the same as the gas barrier packaging material 10 of the first embodiment except that an anchor coat layer 5 is further provided between the substrate 1 and the barrier layer 3.

(Anchor coat layer)
The anchor coat layer 5 is provided in order to improve the adhesion between the substrate 1 and the barrier layer 3.

As a material constituting the anchor coat layer 5, various resins can be used. Examples of the resin include alkyd resin, melamine resin, acrylic resin, polyurethane resin, polyester resin, phenol resin, amino resin, fluororesin, epoxy resin, aqueous polyurethane resin, polyvinyl alcohol polymer and derivatives thereof, carboxymethyl cellulose, hydroxy Cellulose derivatives such as ethyl cellulose, starches such as oxidized starch, etherified starch, dextrin, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid or esters thereof, salts and copolymers thereof, aqueous polyester resin, polyhydroxyethyl methacrylate and Examples thereof include vinyl polymers such as copolymers, and functional group-modified polymers such as carboxyl groups of these various polymers. Any one of these resins may be used alone, or two or more resins may be used in combination.
The material constituting the anchor coat layer 5 is preferably a polyurethane resin, a polyester resin, a mixture of an aqueous polyurethane resin and a polyvinyl alcohol polymer, or an aqueous polyester resin.

  It is preferable that a curing agent is blended in the resin. The curing agent is not particularly limited as long as it has reactivity with the resin to be blended. For example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene. Diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, water dispersible (water soluble) carbodiimide, water soluble epoxy compound, water dispersible (water soluble) oxazolidone compound, water soluble aziridine compound A water dispersible polyisocyanate curing agent or the like is preferably used.

The thickness of the anchor coat layer 5 is not particularly limited as long as a uniform coating film can be formed, but is preferably 0.01 μm to 10 μm, and more preferably 0.05 μm to 5 μm.
If the thickness of the anchor coat layer 5 is equal to or greater than the lower limit of the above range, a uniform film is easily obtained, which is excellent in terms of adhesion to the substrate 1. If the thickness of the anchor coat layer 5 is not more than the upper limit of the above range, the anchor coat layer 5 has good flexibility (flexibility), and there is no possibility that the coating film will crack due to external factors.

(Method for producing gas barrier packaging material)
The gas barrier packaging material 20 can be manufactured, for example, by the following manufacturing method (II).
Production method (II):
A step of applying a coating liquid containing a resin on one surface of the substrate 1 and drying to form the anchor coat layer 5 (hereinafter also referred to as “step (β1)”);
On the surface of the substrate 1 on which the anchor coat layer 5 is formed, a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound ( b4) and a gas barrier coating solution containing a solvent are applied to form a coating film composed of the gas barrier coating solution, and the coating layer is dried to form the barrier layer 3 (hereinafter referred to as “step (hereinafter referred to as“ step ”). β2) ")), and
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to all carboxyl groups in the polycarboxylic acid polymer (b1),
The carbonic acid component equivalent content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal,
The method for producing a gas barrier packaging material, wherein the coating film is dried so that an ammonia content measured by GC per 100 cm ² of the obtained gas barrier packaging material is 2000 µg or less.
In addition, if there exists a commercial item in which the anchor coat layer 5 was formed on one surface, there is no problem and the step (β1) may be omitted.

[Step (β1)]
The coating liquid (hereinafter also referred to as “coating liquid A”) used for forming the anchor coat layer 5 includes a resin and a solvent. You may include a hardening | curing agent etc. as needed.
The resin used for the coating liquid A is the same as the resin mentioned as the material constituting the anchor coat layer 5.
The solvent used in the coating liquid A is not particularly limited, and examples thereof include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, and dimethyl form. Examples thereof include organic solvents such as amide, dimethylacetamide, toluene, hexane, heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate and butyl acetate.
The solid content concentration of the coating liquid A is preferably 0.5 to 50% by mass with respect to the total amount (100% by mass) of the coating liquid A from the viewpoint of coating suitability.

It does not specifically limit as a coating method of the coating liquid A, For example, the various coating methods quoted by the above-mentioned process ((alpha) 1) can be used.
It does not specifically limit as a drying method, For example, the various drying methods quoted at the above-mentioned process ((alpha) 1) can be used.
Although drying temperature is not specifically limited, When using water or a mixed solvent of water and an organic solvent as a solvent, 40 to 160 degreeC is preferable normally.
The drying pressure is usually preferably normal pressure or reduced pressure, and preferably normal pressure from the viewpoint of facility simplicity.

[Step (β2)]
Examples of the gas barrier coating liquid are the same as those described in the first embodiment.
The step (β2) can be performed in the same manner as the step (α1) in the first embodiment.
The step (β2) may be performed continuously from the step (β1), or may be performed discontinuously through a winding step and a curing step.

<Third Embodiment>
FIG. 3 is a cross-sectional view schematically showing a gas barrier packaging material according to a third embodiment of the present invention.
The gas barrier packaging material 30 of this embodiment includes a base material 1, a lower barrier layer 7 laminated on one surface of the base material 1, and an upper barrier layer 9 (barrier layer (B )).
The upper barrier layer 9 is the same as the barrier layer 3 of the first embodiment. That is, the gas barrier packaging material 20 is the same as the gas barrier packaging material 10 of the first embodiment except that the lower barrier layer 7 is further provided between the substrate 1 and the barrier layer 3.

(Lower barrier layer)
The lower barrier layer 7 may be the same as the upper barrier layer 9 or may be another barrier layer different from the upper barrier layer 9.
Examples of other barrier layers include those formed by a vapor deposition method, and those formed by a coating method such as the upper barrier layer 9.

An inorganic vapor deposition layer is mentioned as an example of the barrier layer formed by the vapor deposition method. The inorganic vapor deposition layer is a layer of an inorganic material formed by a vapor deposition method. The inorganic vapor-deposited layer is preferable for enhancing the gas barrier properties of the gas barrier packaging material 30, such as oxygen barrier properties, water vapor barrier properties, etc., in particular, water vapor barrier properties.
As the inorganic material constituting the inorganic vapor deposition layer, an inorganic material capable of constituting an inorganic vapor deposition layer for imparting gas barrier properties such as oxygen barrier properties and water vapor barrier properties is appropriately selected. Examples thereof include aluminum, aluminum oxide, magnesium oxide, silicon oxide, and tin oxide. An inorganic material is used combining 1 type (s) or 2 or more types as needed.
The inorganic material is preferably at least one selected from the group consisting of aluminum, aluminum oxide, magnesium oxide and silicon oxide from the viewpoint of high gas barrier properties.

Aluminum oxide preferably has an abundance ratio of aluminum (Al) and oxygen (O) in a molar ratio of Al: O = 1: 1.5 to 1: 2.0. For example, an aluminum oxide vapor deposition layer is formed by reactive vapor deposition, reactive sputtering, reactive ion plating, etc. in which a thin film is formed in the presence of a mixed gas of oxygen, carbon dioxide gas, and inert gas, using aluminum as a vapor deposition material. Can be formed. At this time, if aluminum is reacted with oxygen, it is stoichiometrically Al ₂ O ₃ , so the abundance ratio of aluminum (Al) and oxygen (O) is a molar ratio, and Al: O = 1: Should be 1.5. However, depending on the vapor deposition method, some may exist as aluminum or aluminum peroxide, and the presence of elements in the aluminum oxide vapor deposition layer using an X-ray photoelectron spectrometer (XPS) or the like. When the ratio is measured, it is generally found that the abundance ratio of aluminum (Al) to oxygen (O) is a molar ratio, and it cannot be said that Al: O = 1: 1.5. In general, when the abundance ratio of aluminum (Al) and oxygen (O) is a molar ratio and the amount of oxygen is less than Al: O = 1: 1.5 and the amount of aluminum is large, the aluminum oxide vapor deposition layer becomes dense. Although good gas barrier properties can be obtained, the aluminum oxide vapor-deposited layer tends to be colored black and the light transmission amount tends to be low. On the other hand, when the abundance ratio of aluminum (Al) and oxygen (O) is a molar ratio and the amount of oxygen is larger than Al: O = 1: 1.5 and the amount of aluminum is small, the aluminum oxide vapor deposition layer becomes sparse. Although the gas barrier property is poor, the light transmission amount is high and transparent.
Silicon oxide is preferably used particularly when the inorganic vapor deposition layer requires water resistance.

Although the thickness of an inorganic vapor deposition layer changes also with the uses of the gas barrier packaging material 30, and the thickness of the 2nd barrier layer 9, it is preferable that it is 5-300 nm, and it is more preferable that it is 10-50 nm. When the thickness of the inorganic vapor deposition layer is not less than the lower limit of the above range, the continuity of the inorganic vapor deposition layer is good and the gas barrier property is excellent. If the thickness of the inorganic vapor deposition layer is not more than the upper limit of the above range, the inorganic vapor deposition layer is excellent in flexibility (flexibility), and cracks due to external factors such as bending and pulling are unlikely to occur.
The thickness of the inorganic vapor deposition layer can be calculated from the result of a calibration curve obtained by measuring a similar sample in advance with a transmission electron microscope (TEM) using, for example, a fluorescent X-ray analyzer.

Examples of other barrier layers formed by the coating method include layers formed by coating a coating liquid containing a barrier resin and a solvent. The coating liquid may contain a curing agent or the like as necessary.
Various barrier resins can be used as the barrier resin, and examples thereof include polyvinylidene chloride (PVDC) and polyvinyl alcohol (PVA).
The solvent is not particularly limited. For example, water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, toluene , Hexane, heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate, butyl acetate and the like.
From the viewpoint of coating suitability, the solid content concentration of the coating liquid is preferably 0.5 to 50% by mass with respect to the total amount (100% by mass) of the coating liquid.

(Method for producing gas barrier packaging material)
The gas barrier packaging material 30 can be manufactured, for example, by the following manufacturing method (III).
Production method (III):
A step of forming the lower barrier layer 7 on one surface of the substrate 1 (hereinafter also referred to as “step (γ1)”);
On the surface of the substrate 1 on which the lower barrier layer 7 is formed, a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound ( a step of applying a gas barrier coating liquid containing b4) and a solvent to form a coating film comprising the gas barrier coating liquid, and drying the coating film to form the upper barrier layer 9 (hereinafter referred to as “process”). (Also referred to as (γ2) ”),
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to all carboxyl groups in the polycarboxylic acid polymer (b1),
The carbonic acid component equivalent content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal,
The method for producing a gas barrier packaging material, wherein the coating film is dried so that an ammonia content measured by GC per 100 cm ² of the obtained gas barrier packaging material is 2000 µg or less.

[Step (γ1)]
When the lower barrier layer 7 is the same as the upper barrier layer 9, the step (γ1) can be performed in the same manner as the step (α1) in the first embodiment.
When the lower barrier layer 7 is another barrier layer different from the upper barrier layer 9, the other barrier layer can be formed by a known method.
If the lower barrier layer 7 is another barrier layer and there is a commercially available product in which the lower barrier layer 7 is formed on one surface, there is no problem, and the step (γ1) may be omitted.

When the other barrier layer is formed by a vapor deposition method (such as an inorganic vapor deposition layer), various known vapor deposition methods can be used for the formation. For example, a vacuum deposition method, a sputtering method, an ion plating method, a chemical vapor deposition method, and the like can be given.
As a heating means of the vacuum deposition apparatus by the vacuum deposition method, an electron beam heating method, a resistance heating method, an induction heating method, or the like is preferably used. Further, in order to improve the adhesion of the lower barrier layer 7 to the substrate 1 and the denseness of the lower barrier layer 7, in addition to the heating means, a plasma assist method or an ion beam assist method can be used.
At the time of vapor deposition, in order to increase the transparency of the inorganic vapor deposition layer, reactive vapor deposition may be performed by blowing oxygen gas or the like.

When the other barrier layer is formed by a coating method, a coating liquid for forming the barrier layer (for example, a coating liquid containing the above-described barrier resin and solvent) is applied onto the substrate 1 and dried. Can be formed.
It does not specifically limit as a coating method of a coating liquid, For example, the various coating methods quoted by the above-mentioned process ((alpha) 1) can be used.
It does not specifically limit as a drying method, For example, the various drying methods quoted at the above-mentioned process ((alpha) 1) can be used.
Although drying temperature is not specifically limited, When using water or a mixed solvent of water and an organic solvent as a solvent, 40 to 160 degreeC is preferable normally.
The drying pressure is usually preferably normal pressure or reduced pressure, and preferably normal pressure from the viewpoint of facility simplicity.

[Process (γ2)]
Examples of the gas barrier coating liquid are the same as those described in the first embodiment.
The step (γ2) can be performed in the same manner as the step (α1) in the first embodiment.

  Although the gas barrier packaging material of the present invention has been described with reference to the first to third embodiments, the present invention is not limited to these embodiments. Each configuration in the above embodiment, a combination thereof, and the like are examples, and the addition, omission, replacement, and other modifications of the configuration can be made without departing from the spirit of the present invention.

For example, in the first embodiment to the second embodiment, the example in which the barrier layer 3 is laminated on one surface of the base material 1 has been described, but the barrier layer 3 may be laminated on both surfaces of the base material 1. . In this case, the barrier layer 3 laminated on one surface and the barrier layer 3 laminated on the other surface may be the same or different. For example, the composition of the gas barrier coating solution used for each barrier layer, the thickness of each barrier layer, and the like may be different. Similarly, the anchor coat layer 5 in the second embodiment and the first barrier layer 7 and the second barrier layer 9 in the third embodiment may be laminated on both surfaces of the substrate 1.
Even if the anchor coat layer 5 is provided between any one or both between the base material 1 and the first barrier layer 7 and between the first barrier layer 7 and the second barrier layer 9 in the third embodiment. Good.
The gas barrier packaging material of the present invention may be composed only of the barrier layer 3.

<Application (Lamination)>
Other base materials may be laminated on the gas barrier packaging material of the above-described embodiment for the purpose of imparting strength, providing sealing properties, providing easy opening at the time of sealing, providing design properties, and providing light blocking properties. Moreover, after laminating | stacking another base material on a gas-barrier packaging material, you may give at least 1 type of process selected from the group which consists of a retort process, a boil process, and a humidity control process.
Other substrates are appropriately selected according to the purpose, but usually plastic films and papers are preferably used. Further, such plastic films and papers may be used alone, in a laminate of two or more, or may be used by laminating plastic films and papers.
It does not specifically limit as a form of another base material, For example, forms, such as a film, a sheet | seat, a bottle, a cup, a tray, a tank, a tube, are mentioned. Among these base materials, from the viewpoint of laminating gas barrier packaging materials, films and sheets are preferable, and sheets before cup molding and flattened tubes are also preferable.
Examples of a method for laminating the gas barrier packaging material and another base material include a method of laminating by an laminating method using an adhesive. Specific examples of the laminating method include a dry laminating method, a wet laminating method, and an extrusion laminating method.

Although it does not specifically limit as a lamination | stacking aspect of the gas-barrier packaging material of this embodiment and another base material, From a viewpoint of the handleability as a product, for example,
(A) Gas barrier packaging material / polyolefin,
(B) Gas barrier packaging material / polyolefin (tubular) / gas barrier packaging material,
(C) Gas barrier packaging material / nylon / polyolefin,
(D) Gas barrier packaging material / polyolefin / paper / polyolefin,
(E) Polyolefin / gas barrier packaging material / polyolefin,
(F) polyolefin / gas barrier packaging material / nylon / polyolefin,
(G) Polyethylene terephthalate / gas barrier packaging material / nylon / polyolefin and the like.
Moreover, these lamination | stacking aspects can also be laminated | stacked repeatedly.

In these lamination modes, a printing layer or a vapor deposition layer of a metal or a silicon compound may be laminated from the viewpoints of designability, light blocking, moisture resistance, and the like.
When the gas barrier packaging material is a laminate, the laminated surface of the gas barrier packaging material is preferably not arranged in the outermost layer from the viewpoint of gas barrier properties. When the laminated surface of the gas barrier packaging material is disposed in the outermost layer, the barrier layer or the like is scraped, causing a reduction in gas barrier properties.

<Effect>
In the gas barrier packaging material of the present invention, by providing the barrier layer (B), high oxygen barrier properties and water vapor barrier properties are exhibited even when the inorganic vapor deposition layer is not provided. Further, the oxygen barrier property and the water vapor barrier property are not easily affected by humidity, and the oxygen barrier property and the water vapor barrier property are not easily lowered even under high humidity.

  Therefore, the gas barrier packaging material of the present invention is suitably used as a gas barrier packaging material for precision metal parts such as foods, beverages, medicines, pharmaceuticals, and electronic parts, which are easily deteriorated by the influence of oxygen, humidity and the like.

Hereinafter, the present invention will be described in detail with reference to examples. However, the present invention is not limited to these examples.
The measurement method, material, and apparatus used in each example are shown below.

〔Measuring method〕
<Measurement of oxygen permeability (OTR)>
The oxygen permeability (OTR) of the packaging material was measured using an oxygen permeation tester OXTRAN (registered trademark) 2/20 manufactured by Modern Control under the conditions of a temperature of 30 ° C. and a relative humidity of 70%. The measuring method was based on ASTM F1927-98 (2004), and the measured value was expressed in the unit cm ³ (STP) / (m ² · day · MPa). Here, (STP) means standard conditions (0 ° C., 1 atm) for defining the volume of oxygen.

<Measurement of water vapor transmission rate (WVTR)>
The water vapor permeability (WVTR) of the packaging material was measured for moisture permeability at a temperature of 40 ° C. and a relative humidity of 90% using PERMATRAN-W 3/31 manufactured by Modern Control (ASTM F1249-01). The measured value was expressed in the unit of g / (m ² · day).

<Measurement of residual ammonia amount>
The residual ammonia amount of the packaging material was measured using Shimadzu GC-14B (gas chromatograph), inlet temperature 180 ° C., column temperature 80 ° C., flow rate 30 mL / min, detector temperature 200 ° C., current 120 mA, column porapakQ. (Inner diameter: 3.2 mm × 3.1 m), measured with a carrier gas He.
The sample used was a 10 cm × 10 cm sample piece. A sample piece was sealed in a vial (30 mL), heated in an oven at 180 ° C. for 30 minutes, extracted with a syringe by 0.5 mL, and rapidly injected. The measured value was expressed in unit μg / 100 cm ² .

<Measurement of IR spectrum>
The IR spectrum of the packaging material was measured by the ATR method using an Auto Image (IR spectroscopic analyzer) manufactured by Perkin Elmer. For the crystal plate, germanium was used, and the measurement was performed at an incident angle of 45 degrees, a resolution of 4 cm ⁻¹ , and an integration count of 10 times. Maximum peak height of absorbance, a line connecting a straight line and the absorbance of the absorbance and 1900 cm ^-1 of 900 cm ^-1 and a ^baseline, 1300～1490Cm ^-1, each of 1490~1659cm ^-1, 1660~1750cm -1 The maximum value of absorbance (Abs) in the wave number range was read. The ratio (α / β) and ratio (β / γ) were calculated from the determined maximum peak heights (α), (β), and (γ).

[Materials and equipment]
As the polycarboxylic acid, polyacrylic acid (number average molecular weight 250,000, Wako first grade) manufactured by Wako Pure Chemicals was used.
As zinc oxide, zinc oxide manufactured by Wako Pure Chemical Industries (Wako Grade 1) was used.
As the copper oxide, Wako Pure Chemical Industries copper (II) oxide was used.
As ammonia water, ammonia water (25%, Wako first grade) manufactured by Wako Pure Chemical Industries, Ltd. was used.
As the ammonium hydrogen carbonate, ammonium hydrogen carbonate (special grade reagent) manufactured by Wako Pure Chemical Industries, Ltd. was used.
As ammonium carbonate, ammonium carbonate (special grade reagent) manufactured by Wako Pure Chemical Industries, Ltd. was used.
As the Si agent, 3-glycidoxypropyltrimethoxysilane manufactured by Wako Pure Chemical Industries, Ltd. was used.
As 2-propanol, Wako Pure Chemical Industries 2-propanol (Wako first grade) was used.
As the PET film, a biaxially stretched polyethylene terephthalate film Lumirror (registered trademark) P60 (thickness: 12 μm) manufactured by Toray Film Processing Co., Ltd. was used.
As the vapor-deposited PET film, an aluminum oxide vapor-deposited biaxially stretched polyethylene terephthalate film Barrierlox (registered trademark) 1011HG (thickness: 12 μm) manufactured by Toray Film Processing Co., Ltd. was used.
As the nylon film, a stretched nylon film Emblem (registered trademark) ONMB (thickness 15 μm) manufactured by Unitika Ltd. was used.
As the polypropylene film, polypropylene film Treffan (registered trademark) ZK207 (thickness 60 μm) manufactured by Toray Film Processing Co., Ltd. was used.
As the adhesive, a two-component curable adhesive Takelac (registered trademark) A620 (main agent) / Takenate (registered trademark) A65 (curing agent) manufactured by Mitsui Chemicals Polyurethanes was used.
As a laminator, a multi coater TM-MC manufactured by HIRANO TECSEED was used.
The bar coater used was a bar coater (# 6) manufactured by Matsuo Sangyo.

[Preparation Examples 1-9]
Coating materials 1 to 9 were prepared by mixing and stirring the materials shown in Table 1.

[Example 1]
A PET film is used as a base material, and the coating liquid 1 is applied to one surface of the base material by a bar coater, dried in an oven at 60 ° C. for 1 minute, and then heat-treated in an oven at 180 ° C. for 3 minutes. Was performed to form a barrier layer having a thickness of 0.3 μm to obtain a gas barrier packaging material having a base material / barrier layer structure.

[Examples 2-8, Comparative Examples 1-2]
A gas barrier packaging material was obtained in the same manner as in Example 1 except that the coating liquid shown in Table 2 was used in place of the coating liquid 1 and drying and heat treatment were performed under the drying conditions and heat treatment conditions shown in Table 2.

Example 9
A gas barrier packaging material was obtained in the same manner as in Example 1 except that the coating liquid 3 was used in place of the coating liquid 1 and a vapor-deposited PET film was used as the substrate.

Example 10
The gas barrier packaging material obtained in Example 1 was bonded to a nylon film (hereinafter referred to as “Ny”) and a polypropylene film (hereinafter referred to as “CPP”) by a laminator, and cured in an oven at 40 ° C. for 3 days. A gas barrier packaging material having a layer structure of substrate / barrier layer / adhesive / Ny / adhesive / CPP was obtained.

Example 11
The gas barrier packaging material obtained in Example 9 was bonded to Ny and CPP with a laminator and cured in an oven at 40 ° C. for 3 days to obtain a substrate / barrier layer / adhesive / Ny / adhesive / CPP. Thus, a gas barrier packaging material having a layer structure was obtained.

Example 12
The two gas barrier packaging materials obtained in Example 9 were bonded together by a laminator and cured for 3 days in an oven at 40 ° C., and the layer constitution of substrate / barrier layer / adhesive / barrier layer / substrate was obtained. A gas barrier packaging material was obtained.

Example 13
The two gas barrier packaging materials obtained in Example 9 were bonded to Ny and CPP by a laminator and cured in an oven at 40 ° C. for 3 days to obtain a substrate / barrier layer / adhesive / substrate / barrier. A gas barrier packaging material having a layer constitution of layer / adhesive / Ny / adhesive / CPP was obtained.

About the gas barrier packaging material obtained in each example, ratio (α / β), ratio (β / γ), ammonia content per 100 cm ² (residual NH ₃ ), oxygen permeability (OTR), water vapor permeability ( WVTR) was measured. The results are shown in Tables 2-3.

As shown in the above results, the gas barrier properties of Examples 1 to 13 in which the ratio (α / β) of the barrier layer is 0.6 or more, the ratio (β / γ) is 1.0 or more, and the residual NH ₃ is 2000 μg or less. The packaging material had low oxygen permeability (OTR) and water vapor permeability (WVTR), and high oxygen barrier properties and water vapor barrier properties.
On the other hand, the gas barrier packaging material of Comparative Example 1 having a residual NH ₃ of 3000 μg even when the ratio (α / β) of the barrier layer is 0.6 or more and the ratio (β / γ) is 1.0 or more is Further, the oxygen barrier property and the water vapor barrier property, particularly the oxygen barrier property were low.
The ratio (α / β) of the barrier layer obtained using the coating liquid 9 in which the content of the amphoteric polyvalent metal compound is 0.7 chemical equivalents relative to all the carboxyl groups in the polycarboxylic acid polymer. The gas barrier packaging material of Comparative Example 2 with 0.5 had low oxygen barrier properties and water vapor barrier properties.

DESCRIPTION OF SYMBOLS 1 Base material 3 Barrier layer 5 Anchor coat layer 7 1st barrier layer 9 2nd barrier layer 10 Gas barrier packaging material 20 Gas barrier packaging material 30 Gas barrier packaging material

Claims (6)

A barrier layer (B),
The maximum peak height (β) of absorbance in the range of 1490 to 1659 cm ⁻¹ and the maximum peak height of absorbance in the range of 1300 to 1490 cm ⁻¹ when the infrared absorption spectrum of the barrier layer (B) is measured. The ratio (α / β) to the thickness (α) is 0.6 or more, and the maximum peak height (γ) of the absorbance within the range of 1660 to 1750 cm ⁻¹ , the maximum peak height (β) Ratio (β / γ) is 1.0 or more,
A gas barrier packaging material, wherein the ammonia content measured by gas chromatography per 100 cm ² is 2000 μg or less.   The gas barrier packaging material according to claim 1, wherein the barrier layer (B) contains a polycarboxylic acid polymer.   The gas barrier packaging material according to claim 1 or 2, wherein the barrier layer (B) contains a polyvalent metal. The oxygen permeability measured under conditions of a temperature of 30 ° C. and a relative humidity of 70% is 5 cm ³ (STP) / (m ² · day · MPa) or less, and is measured under a temperature of 40 ° C. and a relative humidity of 90%. The gas barrier packaging material according to any one of claims 1 to 3, wherein the water vapor permeability is 1 g / (m ² · day) or less. A method for producing a gas barrier packaging material comprising a barrier layer (B),
Drying a coating film comprising a gas barrier coating solution containing a polycarboxylic acid polymer (b1), an amphoteric polyvalent metal compound (b2), ammonia (b3), a carbonic acid component-containing compound (b4), and a solvent. And forming a barrier layer (B),
The content of the amphoteric polyvalent metal compound (b2) in the gas barrier coating solution is 1.0 chemical equivalent or more with respect to all the carboxyl groups in the polycarboxylic acid polymer (b1),
The ammonia (b3) content is 4.0 chemical equivalents or more with respect to the number of moles in terms of polyvalent metal of the amphoteric polyvalent metal compound (b2),
The carbonic acid component equivalent content of the carbonic acid component-containing compound (b4) is 1.0 chemical equivalent or more with respect to the number of moles of the amphoteric polyvalent metal compound (b2) in terms of polyvalent metal,
The method for producing a gas barrier packaging material, wherein the coating film is dried so that the ammonia content measured by gas chromatography per 100 cm ² of the obtained gas barrier packaging material is 2000 μg or less. .   The method for producing a gas barrier packaging material according to claim 5, wherein the coating film is dried by heat treatment at 160 to 250 ° C for 30 seconds to 10 minutes.

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