JP6497053B2 - Gas barrier coating liquid and gas barrier packaging material - Google Patents

Description

  The present invention relates to a gas barrier coating solution and a gas barrier packaging material.

  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 excellent gas barrier properties such as oxygen under dry conditions. However, the packaging material made of these polymers has a problem that the gas barrier property such as oxygen is greatly lowered due to its hydrophilicity under a high humidity condition, and a problem that resistance to humidity and hot water is poor.

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 gas barrier property even under high humidity.
However, such a gas barrier packaging material requires a plurality of types of coating liquids during production, 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 was necessary to retort or expose to a humid environment for a long time.

In Patent Document 4, a solution or dispersion of a mixture containing a polycarboxylic acid polymer, a polyvalent metal compound, one of a volatile base or acid, and a solvent is applied onto each of the two inorganic layers. A method has been proposed in which two organic thin films each having an inorganic layer laminated on one surface are obtained and each organic thin film is laminated to obtain a laminated film for a moisture-proof film. In the aforementioned Patent Document 1, a method using a solution or dispersion of a mixture containing a polycarboxylic acid polymer, a polyvalent metal compound, a volatile base, and a solvent is also proposed.
In these solutions or dispersions, the reaction between the polycarboxylic acid polymer and the polyvalent metal compound is suppressed by a volatile base or acid. After coating, the reaction between the polycarboxylic acid polymer and the polyvalent metal compound proceeds by removing the volatile base or acid from the coating film by drying. Therefore, the layer containing the polyvalent metal salt of the polycarboxylic acid polymer can be formed with a single liquid.
In these solutions or dispersions, in order to suppress solidification due to the reaction between the polycarboxylic acid polymer and the polyvalent metal compound, and the resulting decrease in coating properties, a volatile base that is a reaction inhibitor or A large amount of acid is added.

Japanese Patent No. 4373797 Japanese Patent No. 5012895 JP 2005-125893 A Japanese Patent No. 4765090

However, the liquid stability of the solution or dispersion is insufficient, and precipitation is likely to occur during storage. If precipitation occurs in the liquid, a uniform film cannot be formed.
In addition, if the volatile base or acid remains, the reaction between the polycarboxylic acid polymer and the polyvalent metal compound is hindered, and the gas barrier property becomes insufficient. It is necessary to remove the acid sufficiently. However, since a large amount of volatile base or acid is blended, a large amount of heat is required for drying. Furthermore, when ammonia is used as the volatile base, there is also a problem that the working environment is deteriorated due to a large amount of ammonia volatilizing.

  The present invention has been made in view of the above circumstances, and even when the content of the volatile base or acid is small, the coating property is good, and the polyvalent metal salt of the polycarboxylic acid polymer can be obtained in a single solution. An object of the present invention is to provide a gas barrier coating liquid that can form a layer containing the liquid and has excellent liquid stability, and a gas barrier packaging material using the same.

The present invention has the following aspects.
[1] The following components (A), (B), (C), (D) and a solvent are included,
When the number of moles of the component (B) is 1, the total number of moles of the component (C) and moles of the component (D) is 0.05 to 8.5 moles. Gas barrier coating liquid.
(A): a polycarboxylic acid polymer.
(B): Multivalent metal ion.
(C): Volatile base or acid (except carbonic acid).
(D): Carbonate ion.
[2] [1] a layer a coating film formed by drying consisting barrier coating solution according to, when measuring the infrared absorption spectrum by the transmission ^method, the range of 1490cm ^-1 ~1659cm -1 gas barrier comprising the maximum peak height in absorbance inner and ^(alpha), the layer ratio (α / β) is 1 or more and maximum peak height absorbance in the range of 1660cm ^-1 ~1750cm -1 (β) Packaging material.

  According to the present invention, the coating property is good even when the content of the volatile base or acid is small, a layer containing a polyvalent metal salt of a polycarboxylic acid polymer can be formed in one liquid, and the liquid stability It is possible to provide a gas barrier coating solution that is excellent in gas resistance and a gas barrier packaging material using the same.

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.

≪Gas barrier coating liquid≫
The gas barrier coating liquid of the present invention comprises the following component (A), component (B), component (C), component (D), and solvent:
When the number of moles of the component (B) is 1, the total number of moles of the component (C) and moles of the component (D) is 0.05 to 8.5 moles. And
(A): a polycarboxylic acid polymer.
(B): Multivalent metal ion.
(C): Volatile base or acid (except carbonic acid).
(D): Carbonate ion.
The coating liquid for gas barrier of the present invention is a component other than the component (A), the component (B), the component (C), the component (D) and the solvent as long as the effects of the present invention are not impaired. May further be included.

<(A) component>
The “polycarboxylic acid polymer” is a polymer having two or more carboxyl groups in the molecule.
Examples of the component (A) include (co) polymers of ethylenically unsaturated carboxylic acids; copolymers of ethylenically unsaturated carboxylic acids and other ethylenically unsaturated monomers; alginic acid, carboxymethylcellulose, pectin And acidic polysaccharides having a carboxyl group in the molecule. 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.

As the component (A), from the viewpoint of gas barrier properties of the obtained gas barrier packaging material, at least one polymerizable property selected from the group consisting of acrylic acid, maleic acid, methacrylic acid, itaconic acid, fumaric acid and crotonic acid. Polymers containing structural units derived from monomers are 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.

As the component (A), among the above, a polymer containing 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 is preferable. .
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 component (A) is preferably 2,000 to 10,000,000. If the number average molecular weight of the polycarboxylic acid polymer is 2,000 or more, the resulting gas barrier packaging material has better water resistance, and gas barrier properties and transparency may deteriorate due to moisture, or whitening may occur. Absent. When the number average molecular weight of the component (A) is 10,000,000 or less, the viscosity of the gas barrier coating liquid of the present invention does not become too high, and the coating property is hardly impaired.
The number average molecular weight of the component (A) is more preferably 5,000 to 1,000,000 from the viewpoint of water resistance of the obtained gas barrier packaging material.
In addition, the number average molecular weight of (A) component is the number average molecular weight of polystyrene conversion calculated | required by the gel permeation chromatography (GPC).
(A) A component may be used individually by 1 type and may use 2 or more types together.

<(B) component>
The component (B) is a polyvalent metal ion.
“Polyvalent metal ion” is a metal ion having a valence of 2 or more.
Specific examples of polyvalent metal ions include alkaline earth metal ions such as beryllium ions, magnesium ions, calcium ions, titanium ions, zirconium ions, chromium ions, manganese ions, iron ions, cobalt ions, nickel ions, copper ions, Examples include transition metal ions such as zinc ions, aluminum ions, and the like.
These (B) components may be used individually by 1 type, or may use 2 or more types together.

As the component (B), divalent metal ions are preferable from the viewpoint of gas barrier properties and manufacturability of the gas barrier packaging material.
Among these, at least one selected from the group consisting of alkaline earth metal ions, cobalt ions, nickel ions, copper ions and zinc ions is preferable, and selected from the group consisting of magnesium ions, calcium ions, copper ions and zinc ions. At least one is particularly preferred.

<(C) component>
The component (C) is a volatile base or acid (excluding carbonic acid).

  Examples of the volatile base include ammonia, methylamine, ethylamine, dimethylamine, diethylamine, triethylamine, morpholine, ethanolamine and the like. Among these, ammonia is preferable from the viewpoints of coating solution stability and gas barrier properties.

  As the volatile acid, various inorganic acids and organic acids can be used, and examples thereof include hydrochloric acid, acetic acid, sulfuric acid, oxalic acid, citric acid, malic acid, and tartaric acid.

<(D) component>
(D) A component is a carbonate ion.
In the present invention, “carbonate ion” is a general term for CO ₃ ²⁻ and HCO ₃ ⁻ .
The component (D) contained in the gas barrier coating liquid may be CO ₃ ²⁻ , HCO ₃ ^−, or both CO ₃ ²⁻ and HCO ₃ ⁻ .

<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).

  As the solvent, water or a mixed solvent of water and an organic solvent is preferable from the viewpoint of solubility of the component (A).

<Other ingredients>
Examples of other components include other polymers, monovalent metal compounds, inorganic layered compounds (such as montmorillonite), and 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.

  As another component, you may include the component derived from the supply source of (B) component, or the supply source of (D) component. For example, when the polyvalent metal compound described later is used as the supply source of the component (B) during preparation of the gas barrier coating liquid, a component derived from the polyvalent metal compound may be included. (D) When using the carbonate mentioned later as a supply source of a component, the component derived from carbonate may be included.

<Composition>
In the gas barrier coating liquid of the present invention, when the number of moles of the component (B) is 1, the sum of the number of moles of the component (C) and the number of moles of the component (D) (hereinafter referred to as “(C + D)”. / B ") is 0.05 to 8.5 moles, preferably 3 to 8.5 moles.
When (C + D) / B is within the above range, the liquid stability of the gas barrier coating solution is excellent. For example, even when the component (B) is contained in an amount exceeding 1 chemical equivalent with respect to all the carboxyl groups of the component (A), precipitates are hardly generated in the gas barrier coating solution during storage. In addition, a layer that exhibits excellent gas barrier properties can be formed.

The content of each component in the gas barrier coating liquid of the present invention is not particularly limited as long as (C + D) / B is within the above range.
From the viewpoint of coating suitability, the total content of the component (A) and the component (B) in the gas barrier coating solution is 0.1% by mass to 50% by mass with respect to the total amount of the gas barrier coating solution. Is preferred.

The content of the component (B) in the gas barrier coating solution is preferably 0.2 chemical equivalents or more and 0.8 chemical equivalents or more and 10 chemical equivalents or less with respect to all the carboxyl groups of the component (A). More preferably, it is more preferably 0.8 chemical equivalents or more and 5 chemical equivalents or less.
When the content of the component (B) is 0.2 chemical equivalent or more, the gas barrier property and moisture resistance of the layer formed from the gas barrier coating liquid can be sufficiently improved.

  The content of the component (C) and the content of the component (D) in the gas barrier coating solution are such that (C + D) / B is within the above range.

When the component (C) is a volatile base, the content of the component (C) in the gas barrier coating solution is preferably 1 chemical equivalent or more with respect to all the carboxyl groups of the component (A). It is more preferably 30 chemical equivalents or less, and further preferably 1 chemical equivalent or more and 15 chemical equivalents or less.
By adding one or more chemical equivalents of a volatile base, the component (B) forms a complex with the base. Thereby, it can suppress that (A) component and (B) component react in a coating liquid, and the coating liquid for gas barriers can maintain the state of a transparent and uniform solution.
On the other hand, the lower the volatile base content, the better the gas barrier properties are manifested under conditions of less heat, such as low temperature drying, when the barrier layer is formed by coating and drying the gas barrier coating liquid. be able to. Further, the volatilization amount of the base is small, and the influence on the working environment (for example, an irritating odor caused by ammonia) is reduced.

  When component (C) is a volatile acid, the blending amount of component (C) in the step of producing the gas barrier coating liquid is the same as described above for all carboxyl groups of component (A). 1 chemical equivalent or more, preferably 1 chemical equivalent or more and 30 chemical equivalents or less, more preferably 1 chemical equivalent or more and 10 chemical equivalents or less.

  When the gas barrier coating solution contains an optional additive, the additive amount in the gas barrier coating solution is the ratio of the mass of the component (A) to the mass of the additive (component (A): additive). 70:30 to 99.9: 0.1, and more preferably 80:20 to 98: 2.

<Preparation method>
The gas barrier coating liquid of the present invention can be prepared by dissolving a component (A), a component (B) supply source, a component (C), and a component (D) supply source in a solvent. You may add another component as needed. The order in which the (A) component, the (B) component supply source, the (C) component, and the (D) component supply source are dissolved in the solvent is not particularly limited.
When the supply source of the component (B) also corresponds to the supply source of the component (D) (for example, a carbonate of a polyvalent metal), and the predetermined (C + D) / B can be achieved only by the supply source of the component (B). May prepare the gas barrier coating liquid of the present invention by dissolving the component (A), the supply source of the component (B), and the component (C) in a solvent.

(B) As a supply source of a component, a polyvalent metal, a polyvalent metal compound, etc. are mentioned.
The polyvalent metal is a simple substance of a polyvalent metal element having a metal ion valence of 2 or more. Specific examples of the polyvalent metal include alkaline earth metals such as beryllium, magnesium and calcium, transition metals such as titanium, zirconium, chromium, manganese, iron, cobalt, nickel, copper and zinc, and aluminum.
Specific examples of the polyvalent metal compound include oxides, hydroxides, carbonates, organic acid salts, inorganic acid salts of the above polyvalent metals, ammonium complexes of the above polyvalent metals, and 2-4 of the polyvalent metals. Secondary amine complexes, or carbonates or organic acid salts of these complexes are exemplified. Organic salts include acetate, oxalate, citrate, lactate, phosphate, phosphite, hypophosphite, stearate, monoethylenically unsaturated carboxylate, etc. It is done. Examples of inorganic acid salts include chlorides, sulfates and nitrates. Besides these, polyvalent metal alkylalkoxides can be used as the polyvalent metal compound.
These sources of component (B) may be used alone or in combination of two or more.

  (B) As a supply source of a component, at least 1 sort (s) selected from the group which consists of a bivalent metal and its compound is preferable, and the metal selected from the group which consists of alkaline-earth metal, cobalt, nickel, copper, and zinc More preferred are oxides, hydroxides, carbonates, organic acid salts (for example, acetates), ammonium complexes of metals selected from the group consisting of cobalt, nickel, copper and zinc, and carbonates of the complexes. Among these, metal oxides, hydroxides and carbonates selected from the group consisting of magnesium, calcium, copper and zinc, ammonium complexes of copper or zinc, and carbonates of the complexes are particularly preferable.

As long as the gas barrier property of the gas barrier packaging material is not impaired, a monovalent metal compound, for example, a monovalent metal salt of a polycarboxylic acid polymer is mixed with the supply source of the component (B), or A source of component (B) that contains the monovalent metal compound can be used.
The form of the (B) component supply source is not particularly limited. For example, solid, powder, pellets and the like can be mentioned.

Examples of the supply source of component (D) 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.
As the supply source of the component (D), among the above, ammonium carbonate or ammonium hydrogen carbonate is preferable from the viewpoint that the gas barrier property is not impaired, the handling is easy, and the liquid stability of the gas barrier coating liquid is more excellent.
These sources of component (D) may be used alone or in combination of two or more.

(C + D) / B can be calculated from the raw materials used in the preparation of the gas barrier coating solution.
The gas barrier coating solution uses b (g) zinc oxide as the supply source of the component (B), c (g) ammonia as the component (C), and d (g) ammonium carbonate as the supply source of the component (D). This will be described in more detail with reference to an example.
The zinc oxide b (g) is b / 8.38 mol.
The c (g) of ammonia is c / 18 mol.
The d (g) of ammonium carbonate ((NH ₄ ) ₂ CO ₃ ) is d / 96.09 mol. Therefore, the number of moles of the carbonate component derived from ammonium carbonate is d / 96.09 mole, and the number of moles of the volatile base component derived from ammonium carbonate is 2d / 96.09.
Therefore, the number of moles of (carbonic acid component + volatile base / acid component) is (d / 96.09 + c / 18 + 2d / 96.09) / (b / 81.38).

The chemical equivalents of the component (B) and the component (C) for all the carboxyl groups of the component (A) in the gas barrier coating liquid can be calculated from the raw materials used for the preparation of the gas barrier coating liquid.
The chemical equivalent will be described in detail by taking as an example the case where the component (A) is polyacrylic acid and the source of the component (B) is magnesium 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 0.2 equivalent of magnesium oxide is added to 100 g of polyacrylic acid, 1.39 × 0.2 = 0.278 mol of magnesium oxide is added to neutralize the carboxyl group. do it.
Since the valence of magnesium is divalent and the molecular weight of magnesium oxide is 40, the mass of 0.2 equivalent of magnesium oxide with respect to 100 g of polyacrylic acid is 5.56 g (0.139 mol).

<Effect>
In the gas barrier coating liquid of the present invention, since it contains the component (A), the component (B), and the component (C), the component (A) and the component (B) react with each other in the coating liquid to form a solid. Is suppressed, and coating is possible. Further, when the gas barrier coating liquid is applied onto the support and dried, the component (C) is removed, whereby the components (A) and (B) react in the coating film, A layer containing a polyvalent metal salt of a carboxylic acid polymer is formed. When the polycarboxylic acid polymer is cross-linked with a polyvalent metal, the oxygen barrier property is not easily lowered due to moisture absorption. Therefore, the layer exhibits a high oxygen barrier property not only in a low humidity region but also in a high humidity region.

  Moreover, in the gas barrier coating liquid of the present invention, since the component (D) is contained in such an amount that (C + D) / B is within the above range, the liquid stability is excellent. For example, precipitation is unlikely to occur during storage. Therefore, the uniformity of the formed layer is excellent.

In addition, by including the component (D) in such an amount that (C + D) / B is within the above range, the amount of the component (C) necessary for suppressing the reaction between the component (A) and the component (B) is reduced. Less.
Therefore, in the gas barrier coating liquid of the present invention, the content of the component (C) can be reduced as compared with the conventional case. When the content of the component (C) is small, the component (C) is sufficiently removed even if the drying after coating is performed under a condition with less heat (such as low temperature drying), and the component (A) and the component (B) ) The reaction with the component proceeds satisfactorily and excellent gas barrier properties are easily exhibited. Further, when ammonia is used as a volatile base, the amount of ammonia volatilized during drying is reduced, and a specific irritating odor can be suppressed.

≪Gas barrier packaging material≫
Gas barrier packaging material of the present invention is a layer formed by drying the coating film formed of the gas barrier coating solution of the invention described above, when measuring the infrared absorption spectrum, 1490cm ^-1 ~1659cm ^-1 A layer (α / β) having a ratio (α / β) of 1 or more to the maximum peak height (α) of absorbance within the range of ¹ to the maximum peak height (β) of absorbance within the range of 1660 cm ^{−1 to} 1750 cm ⁻¹ ( (Hereinafter also referred to as “layer (I)”).

When the coating film comprising the gas barrier coating liquid of the present invention is dried, the component (A) and the component (B) react in the coating film to form a polyvalent metal salt of a polycarboxylic acid polymer. . That is, the layer (I) contains a polyvalent metal salt of a polycarboxylic acid polymer.
In the layer (I), the component (B) may form a polyvalent metal salt of a polycarboxylic acid polymer, or may form a polyvalent metal complex salt of a polycarboxylic acid polymer. Further, the unreacted component (B) may be present in the layer (I) as particles, molecules, or the like.
Here, the metal complex means a complex of a polyvalent metal (cobalt, nickel, copper, zinc, etc.) and a volatile base. Examples of the metal complex include zinc and copper tetraammonium complexes.

<Maximum peak height ratio (α / β)>
The ratio (α / β) of the maximum peak height of the absorbance in the infrared absorption spectrum will be described.
The maximum peak height (α) is infrared absorption of C═O stretching vibration of 1560 cm ⁻¹ belonging to a carboxyl group (—COO ⁻ ) forming a salt (hereinafter also referred to as “carboxyl group salt”). It is the maximum peak height of the absorbance of the spectrum. That is, usually, salts of carboxyl groups (-COO ^-) C = O stretching vibration attributable to ^the infrared wave number range of 1490cm ^-1 ~1659cm -1, an absorption peak having an absorption maximum in the vicinity of 1560 cm ^-1 give.

The maximum peak height (β) is the maximum peak height of the absorbance of the infrared absorption spectrum that is separated and independent from the maximum peak height (α), and 1700 cm ⁻¹ of C = attributed to a free carboxyl group (—COOH) It is the maximum peak height of absorbance in the infrared absorption spectrum of O stretching vibration. That is, normally, C = O stretching vibration attributable to the free carboxyl group (-COOH) ^is an infrared wave number range of 1660cm ^-1 ~1750cm -1, giving an absorption peak having an absorption maximum in the vicinity of 1700 cm ^-1.

The absorbance when the infrared absorption spectrum of the layer (I) is measured is proportional to the amount of chemical species having infrared activity present in the gas barrier packaging material.
Therefore, the ratio (α / β) of the maximum peak height of absorbance in the infrared absorption spectrum is such that the polyvalent metal salt of carboxyl group (—COO ⁻ ), the free carboxyl group (—COOH) in layer (I) It can be used as a scale representing the ratio of.

The gas barrier coating solution, within a range not to impair the gas barrier properties, the addition of metal compound comprising a monovalent metal, a monovalent metal salt of a carboxyl group (-COO ^-) C = O stretching vibration attributable to the , 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 this case, the absorption peak of absorbance in the infrared absorption spectrum includes two C═O stretching vibrations derived from a monovalent metal salt of a carboxyl group and a polyvalent metal salt of a carboxyl group. Even in such a case, as described above, the ratio of the maximum peak height (α / β) of the absorbance in the infrared absorption spectrum is such that the polyvalent metal salt of a carboxyl group (—COO ⁻ ) and the free carboxyl group (—COOH) It can be used as a scale that represents the ratio of.

By measuring the ratio (α / β) of the maximum peak height of the absorbance in the infrared absorption spectrum of the layer (I), the ionization degree of the layer (I) can be determined.
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 all carbonyl carbons (assigned to free carboxyl groups and salts of carboxyl groups) of the polycarboxylic acid polymer in 1 g of layer (I). Y is layer (I) It is the number of moles of carbonyl carbon attributed to the salt of the carboxyl group contained in the polycarboxylic acid polymer in 1 g.)

  The degree of ionization is the ratio of the number of carboxyl group salts to the total number of carboxyl groups in the polycarboxylic acid polymer (the total number of free carboxyl groups and carboxyl group salts), and is the maximum absorbance peak in the infrared absorption spectrum. Compared with the height ratio (α / β), it can be determined as a more strict ratio of chemical species.

“All the carboxyl groups of the polycarboxylic acid polymer” means the carboxyl group of the component (A) that was not involved in the reaction, and the polycarboxylic acid produced by the reaction of the components (A) and (B). Contains carboxyl group of polyvalent metal salt of acid. From the measurement of the infrared absorption spectrum, it can be confirmed that a polyvalent metal salt of polycarboxylic acid is produced.
The carboxyl group of the component (A) is a free carboxyl group, and a part thereof may be a monovalent metal salt. The carboxyl group of the polyvalent metal salt of the polycarboxylic acid polymer includes a polyvalent metal salt of a carboxyl group, and may include a free carboxyl group or a monovalent metal salt of a carboxyl group.

The infrared absorption spectrum can be measured using, for example, FT-IR2000 manufactured by PERKIN-ELMER. Specifically, transmission method The infrared absorption spectrum of the sample, ATR method (attenuated total reflection method) were measured by a KBr pellet method, diffuse reflection method, the photoacoustic method (PAS ^{method), 1490cm -1 ~1659cm} -1 maximum peak height absorbance in the range of (alpha) and ^1660cm maximum peak absorbance in the range of ^-1 ~1750cm -1 height (beta) is measured, the ratio of the maximum peak height of absorbance (alpha / beta ).
The infrared absorption spectrum is preferably measured by the transmission method or the ATR method from the viewpoint of simplicity.
Examples of the ATR method include measurement conditions using KRS-5 (thallium bromoiodide), an incident angle of 45 degrees, a resolution of 4 cm ⁻¹ , and an integration count of 30 times.
For the infrared absorption spectrum measurement method using FT-IR, reference can be made to, for example, “The Basics and Practice of FT-IR” by Tasumi Mitsuo.

As a typical measurement condition example of the peak ratio of the infrared absorption spectrum, the gas barrier packaging material comprises a support and a layer (I) formed on the support, and the support and the layer (I) There is a stack of integral, if the support does not absorb light in the optical and 1700 cm ^-1 vicinity of 1560 cm ^-1 vicinity, remains of the laminate, to measure the infrared absorption spectrum. On the other hand, when the support absorbs light of light and 1700 cm ^-1 vicinity of 1560 cm ^-1 vicinity to measure the surface of the layer (I) in the ATR method. As the measurement conditions of the ATR method, from the viewpoint of the penetration depth, Ge (germanium) is used, and the measurement conditions can be given at an incident angle of 45 degrees, a resolution of 4 cm ⁻¹ , and an integration count of 30.

In order to obtain the ionization degree from the measurement result of the infrared absorption spectrum, the ionization degree of the gas barrier packaging material can be calculated using a calibration curve prepared in advance.
The calibration curve used here is created by the following procedure.
The component (A) is neutralized with a known amount of sodium hydroxide in advance, and coated on a plastic film substrate, for example, to prepare a standard sample in the form of a coating film. The C = O stretching vibration of the carbonyl carbon attributed to the free carboxyl group (—COOH) and the carboxyl group salt (—COO ^— Na ⁺ ) in the standard sample thus prepared is separated and detected by measuring the infrared absorption spectrum. be able to. Therefore, obtaining the maximum peak height in absorbance 1560 cm ^-1 and (alpha), the maximum peak height in absorbance 1700 cm ^-1 and (beta) ratio of (α / β). Here, since the component (A) is neutralized with a known amount of sodium hydroxide in advance, the molar ratio of the free carboxyl group (—COOH) and the carboxyl group salt (—COO ^— Na ⁺ ) in the polymer. (Number ratio) is known. Therefore, first, several kinds of standard samples are prepared by changing the amount of sodium hydroxide, and the infrared absorption spectrum is measured.
Next, a calibration curve can be created by regression analysis of the relationship between the ratio of the maximum peak height of absorbance (α / β) and the known molar ratio.
By using the calibration curve, the molar ratio between the free carboxyl group (—COOH) in the sample and the polyvalent metal salt of the carboxyl group (—COO ⁻ ) is obtained from the result of infrared absorption spectrum measurement of the unknown sample. It is done.
From the result, the degree of ionization can be obtained by the equation (1).
The infrared absorption spectrum is mainly derived from the chemical structure of the carboxyl group, and is less affected by the metal species of the salt.

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 support 1 and a barrier layer 3 laminated on one surface of the support 1.

(Support)
Examples of the material constituting the support 1 include plastics, papers, rubbers, and the like. Among these, plastics are preferable from the viewpoint of adhesion to the support 1 and the layer formed on the support 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-based polymers or fluorine-based polymers such as polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, and polyvinylidene fluoride; the aforementioned chlorine-based polymers or fluorine-based 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 support 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.

  The form of the support 1 is not particularly limited, and examples thereof include a film, a sheet, a bottle, a cup, a tray, a tank, and a tube. In the present embodiment, a film or a sheet is preferable from the viewpoint of laminating the barrier layer 3 and the like.

The thickness of the support 1 varies depending on its use and the like, but is preferably 5 μm to 5 cm.
In the use of a film or sheet, the thickness of the support 1 is preferably 5 μm to 800 μm, and more preferably 5 μm to 500 μm.
When the thickness of the support 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 support 1, the surface of the support 1 may be subjected to surface activation treatment such as corona treatment, flame treatment, and plasma treatment.

(Barrier layer)
The barrier layer 3 is the layer (I) described above. In other words, a layer of coating formed by drying consisting barrier coating solution of the present invention, when an infrared absorption spectrum was measured by a transmission method, the maximum absorbance in the range of 1490cm ^-1 ~1659cm ^-1 peak height and ^(alpha), the ratio between the maximum peak height in absorbance in the range of ^{1660cm -1 ~1750cm -1 (β) (} α / β) is one or more layers.

  If the ratio (α / β) of the maximum peak height is 1 or more, the ratio of carboxyl groups that are polyvalent metal salts is sufficiently large among all the carboxyl groups of the polycarboxylic acid polymer, and the barrier The layer 3 exhibits a high oxygen barrier property not only in a low humidity region but also in a high humidity region. That is, since the free carboxyl group having high water absorption is cross-linked with a polyvalent metal, the molecular chain of the polycarboxylic acid polymer is difficult to spread even in a high humidity region, and the oxygen barrier property is not easily lowered.

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, a sufficient oxygen gas barrier can be formed when the barrier layer 3 is formed even under conditions with a small amount of heat, such as low-temperature drying, so that ionic cross-linking with a polyvalent metal is rapidly formed. Sex is expressed.

(Oxygen permeability)
The gas barrier packaging material 10 generally has an oxygen permeability of 30 cm ³ and a relative humidity of 70% of 300 cm ³ (STP) / (m ² · day · MPa) or less, preferably 200 cm ³ (STP) / ( m ² · day · MPa) or less, more preferably 100 cm ³ (STP) / (m ² · day · MPa) or less, particularly preferably 50 cm ³ (STP) / (m ² · day · MPa) or less. It is.

(Method for producing gas barrier packaging material)
The gas barrier packaging material 10 can be manufactured, for example, by a manufacturing method including the following step (α1).
(Α1): A process of forming the barrier layer 3 by applying the gas barrier coating liquid of the present invention on one surface of the support 1 and drying it.

[Step (α1)]
The coating method of the gas barrier coating liquid of the present invention is not particularly limited, and examples thereof include a casting method, a dipping method, a roll coating method, a gravure coating method, a screen printing method, a reverse coating method, a spray coating method, and a kit coating method. , Die coating method, metering bar coating method, chamber doctor combined coating method, curtain coating method and the like.

After the gas barrier coating liquid is applied, the formed coating film is dried to remove the solvent, whereby the barrier layer 3 is formed. For drying, the temperature, time, and the like are set so that the ratio (α / β) of the maximum peak height is 1 or more.
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.
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.

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 support 1, an anchor coat layer 5 laminated on one surface of the support 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 support 1 and the barrier layer 3.

(Anchor coat layer)
The anchor coat layer 5 is provided to improve the adhesion between the support 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 can be easily obtained, which is excellent in terms of adhesion to the support 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 10 can be manufactured, for example, by a manufacturing method including the following steps (β1) and (β2).
(Β1): A step of forming the anchor coat layer 5 by applying a coating liquid containing a resin on one surface of the support 1 and drying it.
(Β2): A step of forming the barrier layer 3 by applying the coating liquid for gas barrier of the present invention on the surface of the support 1 on which the anchor coat layer 5 is formed and drying it.
If there is a commercial product in which the anchor coat layer 5 is formed on one surface, there is no problem even if it is used, 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)]
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 support 1, a lower barrier layer 7 stacked on one surface of the support 1, and an upper barrier layer 9 stacked on the lower barrier layer 7.
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 support 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 a manufacturing method including the following steps (γ1) and (γ2).
(Γ1): A step of forming the lower barrier layer 7 on one surface of the support 1.
(Γ2): a step of forming the upper barrier layer 9 by applying the gas barrier coating liquid of the present invention on the surface of the support 1 on which the lower barrier layer 7 is formed and drying it.

[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 support 1 and the denseness of the lower barrier layer 7, a plasma assist method or an ion beam assist method can be used in addition to the heating means.
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 support 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)]
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 stacked on one surface of the support 1 has been described, but the barrier layer 3 may be stacked on both surfaces of the support 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 support 1.
Even if the anchor coat layer 5 is provided between one or both of the support 1 and the first barrier layer 7 and 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)>
The gas barrier packaging material of the present invention may be laminated with other base materials 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 to the gas-barrier packaging material of this invention, you may give at least 1 sort (s) of processing 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 of the present invention 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 layer (I) (barrier layer 3) formed using the gas barrier coating liquid of the present invention, oxygen excellent in both low and high humidity ranges. Has barrier properties. That is, it is known that the polycarboxylic acid polymer exhibits a high oxygen barrier property in a low humidity region, but in a high humidity region, the molecular chain expands due to moisture absorption and the oxygen barrier property decreases. In the barrier layer 3, since the polycarboxylic acid polymer is a polyvalent metal salt (ionically cross-linked with a polyvalent metal), the molecular chain is difficult to expand and has an excellent oxygen barrier property even in a high humidity region. Show.

In the gas barrier packaging material of the present invention, the layer (I) can be formed by a simple process of applying a gas barrier coating liquid and drying. Therefore, a gas barrier packaging material can be manufactured with a general-purpose coating apparatus without performing a special process (for example, high-temperature and high-pressure processing such as retort processing). Moreover, since oxygen barrier property is expressed by one layer (I), a gas barrier packaging material can be manufactured in one step. Therefore, a gas barrier packaging material can be manufactured at low cost.
Further, in the present invention, as described above, the content of the component (C) in the gas barrier coating liquid can be reduced as compared with the prior art, and the amount of heat required for drying in the manufacturing process of the gas barrier packaging material can be reduced. Can be suppressed. Moreover, when ammonia is used as the volatile base, the irritating odor peculiar to ammonia in the production process can be suppressed by reducing the ammonia content.

  Because of these effects, the gas barrier packaging material of the present invention is suitable as a gas barrier packaging material for precision metal parts such as foods, beverages, medicines, pharmaceuticals, and electronic parts that are susceptible to deterioration due to the influence of oxygen and the like. Used for.

  Hereinafter, the present invention will be described in detail with reference to examples. However, the present invention is not limited to these examples.

[Preparation Example 1]
Coating liquid B1 was prepared by the following procedure.
A polycarboxylic acid polymer, a polyvalent metal compound, ammonia water, ammonium carbonate, and 2-propanol were mixed at a blending ratio shown in Table 1 to prepare a coating liquid B1. (C + D) / B in the coating liquid B1 was 7.92 mol.
As the polycarboxylic acid polymer, polyacrylic acid (Wako first grade, number average molecular weight 5,000) manufactured by Wako Pure Chemical Industries, Ltd. was used.
As the polyvalent metal compound, copper oxide manufactured by Wako Pure Chemical Industries, Ltd. was used.
As the ammonia water, ammonia water (28%, Wako first grade) 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 2-propanol, 2-propanol manufactured by Tokyo Chemical Industry Co., Ltd. was used.

[Preparation Example 2]
A coating solution B2 was prepared in the same manner as in Preparation Example 1, except that the polycarboxylic acid polymer was changed to polyacrylic acid (Wako primary, number average molecular weight 1,000,000) manufactured by Wako Pure Chemical Industries, Ltd. did.

[Preparation Example 3]
Coating liquid B3 was prepared in the same manner as in Preparation Example 1, except that the polyvalent metal compound was changed to zinc oxide (Wako Grade 1) manufactured by Wako Pure Chemical Industries.

[Preparation Example 4]
A coating liquid B4 was prepared in the same manner as in Preparation Example 1 except that the mixing ratio of each material was changed as shown in Table 2. (C + D) / B in the coating liquid B4 was 5.8 mol.

[Preparation Example 5]
A coating solution B5 was prepared in the same manner as in Preparation Example 4 except that the ammonium carbonate of the coating solution B4 was changed to ammonium hydrogen carbonate manufactured by Wako Pure Chemical Industries, Ltd. (C + D) / B in the coating liquid B5 was 5.3 mol.

[Preparation Example 6]
A coating liquid B6 was prepared in the same manner as in Preparation Example 1 except that the mixing ratio of each material was changed as shown in Table 3. (C + D) / B in the coating liquid B6 was 5.3 mol.

[Preparation Example 7]
As an additive, 0.28 g of KBE9007 (3-isocyanatopropyltriethoxysilane) manufactured by Shin-Etsu Silicone Co., Ltd. was added to the coating liquid B1 to prepare a coating liquid B7.

[Preparation Example 8]
A coating solution B8 was prepared in the same manner as in Preparation Example 1 except that ammonium carbonate was not added. (C + D) / B in the coating liquid B8 was 2.63 mol.

[Preparation Example 9]
A coating liquid B9 was prepared in the same manner as in Preparation Example 1 except that the mixing ratio of each material was changed as shown in Table 4. (C + D) / B in the coating liquid B9 was 47.6 mol.

[Preparation Example 10]
A coating liquid B10 was prepared in the same manner as in Preparation Example 1 except that copper oxide was not added.

[Preparation Example 11]
A coating solution B11 was prepared in the same manner as in Preparation Example 1, except that the polycarboxylic acid polymer was not added.

[Preparation Example 12]
A coating solution B12 was prepared in the same manner as in Preparation Example 1, except that polyvinyl alcohol (trade name: Kuraray Poval PVA-105, manufactured by Kuraray Co., Ltd.) was added instead of the polycarboxylic acid polymer.

[Example 1]
As a base material, a coating liquid B1 is applied to one surface of a biaxially stretched polyethylene terephthalate film Lumirror P60 (thickness 12 μm) manufactured by Toray Industries, Inc. using a bar coater (wet 6 μm), and dried in an oven at 80 ° C. A barrier layer having a thickness of 0.3 μm was formed to obtain a base material / barrier layer gas barrier packaging material.

[Example 2]
A gas barrier packaging material for the substrate / barrier layer was obtained in the same manner as in Example 1 except that the substrate was changed to a stretched nylon film (thickness 15 μm) manufactured by Unitika.

[Example 3]
Gas barrier packaging material for base material / barrier layer in the same manner as in Example 1 except that the base material was changed to vapor-deposited PET (polyethylene terephthalate) barrier locks 1011RG-CW (thickness 12 μm) manufactured by Toray Film Processing Co., Ltd. Got.

[Example 4]
As a base material, a biaxially stretched polypropylene film U-1 (thickness 20 μm) manufactured by Mitsui Chemicals Tosero Co., Ltd. was used.
11.1 g of water-based polyester resin (Pesresin A-647GEX solid content 20% by mass, manufactured by Takamatsu Yushi Co., Ltd.) is dissolved in 49.2 g of water, and 1.7 g of water-dispersed polyisocyanate (Duranate WT30-100, manufactured by Asahi Kasei Chemicals Corporation). Was added and stirred. Subsequently, 38.0 g of 2-propanol was added and stirred to obtain an anchor coating agent.
The obtained anchor coating agent was coated on a substrate using a Mayer bar (RK 303-K303 bar manufactured by RK Print-Coat Instruments) so that the thickness after drying was 0.2 μm. And dried for 30 seconds to form an anchor coat layer.
On the anchor coat layer, the coating liquid B1 is applied by a bar coater (wet 6 μm) and dried in an oven at 80 ° C. to form a barrier layer having a film thickness of 0.3 μm. A gas barrier packaging material for the barrier layer was obtained.

[Examples 5 to 10]
As shown in Table 5, the base material / barrier layer gas barrier packaging material was obtained in the same manner as in Example 1 except that the coating liquid B1 was changed to the coating liquids B2 to B7 as shown in Table 5.

[Comparative Examples 1-5]
As shown in Table 5, the base material / barrier layer gas barrier packaging material was obtained in the same manner as in Example 1 except that the coating liquid B1 was changed to the coating liquids B8 to B12 as shown in Table 5.

[Evaluation]
(1) Liquid stability of coating liquid The coating liquids B1 to B12 were observed by visual observation after storage for 1 day immediately after preparation and at room temperature, and the liquid stability was evaluated in the following three stages. The results are shown in Table 5.
A: No precipitation occurs after storage for 1 day.
B: Precipitation did not occur immediately after preparation, but precipitation occurred after storage for 1 day.
C: Precipitation occurred immediately after preparation.

(2) Measurement of oxygen permeability The oxygen permeability of the gas barrier packaging materials of Examples 1 to 10 and Comparative Examples 1 to 5 was measured by the following procedure. The results are shown in Table 5.
The oxygen permeability of the gas barrier packaging material was measured under the conditions of a temperature of 30 ° C. and a relative humidity of 70% using an oxygen permeation tester OXTRAN (registered trademark) 2/20 manufactured by Modern Control.
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.
When the measured value exceeded about 1500 cm ³ (STP) / (m ² · day · MPa), the oxygen permeation tester automatically stopped, and in this case “measurement impossible” was displayed.

(3) Measurement of maximum peak height ratio (α / β) For the gas barrier packaging materials of Examples 1 to 10 and Comparative Examples 1 to 5, the coated surface was measured by the ATR method, and the maximum peak height ratio was measured. (Α / β) was determined. The results are shown in Table 2.

  As shown in Table 5, the coating liquids B1 to B7 used in Examples 1 to 10 were excellent in liquid stability. Further, the gas barrier packaging materials obtained using these coating liquids had a very low oxygen permeability and excellent gas barrier properties as compared with the gas barrier packaging materials of Comparative Examples 1 to 5.

  From the above, the liquid stability of the gas barrier coating liquid of the present invention is excellent, and by using the coating liquid, it is excellent only in a general coating apparatus without performing high heat and high pressure processing such as retort processing. It has been found that a gas barrier packaging material exhibiting gas barrier properties can be produced.

DESCRIPTION OF SYMBOLS 1 Support body 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 (2)

The following (A) component, (B) component, (C) component, (D) component and a solvent,
Wherein when the number of moles of component (B) was 1, the (C) the total mole number of components and the number of moles of the component (D), Ri 0.05 to 7.92 mol der,
Content of said (C) component is 1 chemical equivalent or more and 7 chemical equivalent or less with respect to all the carboxyl groups of said (A) component, The coating liquid for gas barriers characterized by the above-mentioned.
(A): a polycarboxylic acid polymer.
(B): Multivalent metal ion.
(C): a volatile salt groups.
(D): Carbonate ion. Maximum a layer formed by drying the coating film formed of the gas barrier coating solution according to claim 1, when measuring the infrared absorption spectrum, the absorbance in the range of 1490cm ^-1 ~1659cm ^-1 peak height and ^(alpha), gas barrier packaging material ratio (α / β) comprises a layer is one or more of the maximum peak height in absorbance in the range of 1660cm ^-1 ~1750cm -1 (β).

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