WO2022075030A1

WO2022075030A1 - Resin composition, molded object, layered product, gas-barrier material, coating material, and adhesive

Info

Publication number: WO2022075030A1
Application number: PCT/JP2021/034027
Authority: WO
Inventors: 祐章宇佐見; 久美子秋葉
Original assignee: Dic株式会社
Priority date: 2020-10-08
Filing date: 2021-09-16
Publication date: 2022-04-14
Also published as: JPWO2022075030A1

Abstract

Provided is a resin composition containing poly(aspartic acid), which is a biodegradable material. This resin composition has excellent gas-barrier properties and, when used in layered-product formation, does not especially require a post-treatment step for crosslinking reaction. Specifically, this resin composition comprises poly(aspartic acid) and an inorganic component. The inorganic component is preferably an unorganized layered clay mineral and/or a metal oxide. The layered clay mineral preferably includes montmorillonite. The metal oxide preferably includes zinc oxide.

Description

Resin compositions, molded bodies, laminates, gas barrier materials, coating materials and adhesives

The present invention relates to a resin composition, a molded body, a laminated body, a gas barrier material, a coating material and an adhesive.

In the field of flexible packaging materials used for packaging foods and the like, high barrier properties are required for the purpose of maintaining the quality of contents (food safety) and reducing food loss.
In addition, while packaging is useful for protecting the contents, it is no longer needed after the contents are consumed and is discarded, causing problems such as waste plastic problems, marine pollution, and environmental / food contamination. As this problem becomes more serious, the packaging industry is actively developing new environmentally friendly materials. Under these circumstances, the use of highly biodegradable plastics made from biomass resources is expanding.
Polyaspartic acid is a biodegradable material and is a material that can meet the above-mentioned problems. Therefore, it is desired to provide a gas barrier film using polyaspartic acid.
By the way, conventionally, polyvinyl alcohol (PVA) or the like is known as a barrier material for an aqueous resin, but since the hydrophilicity of the resin is high and the barrier property under high humidity is not exhibited, various improvements are being attempted. ..
For example, a gas barrier film (for example, see Patent Document 1) organically crosslinked with a crosslinking agent such as polyamine and / or a polyol in order to reduce humidity dependence, and a water-insoluble biodegradable resin such as polyamino acid. , A water-insoluble biodegradable resin composition containing a layered silicate has been proposed (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2005-225940 Japanese Patent Application Laid-Open No. 2003-113326

In the above-mentioned Cited Document 1, a carboxyl group-containing polyamino acid is mentioned as a polycarboxylic acid used for forming a gas barrier film, and polyaspartic acid is mentioned as the polyamino acid. However, there is no specific example of a gas barrier film using polyaspartic acid in Cited Document 1. From the contents described in Cited Document 1, it is not possible to provide a gas barrier film using polyaspartic acid having a better gas barrier property.
Further, in Cited Document 1, it is necessary to use a cross-linking agent of a polyamine or a polyol for the gas barrier film, and in order to form a film of the gas barrier film, a cross-linking step (post-treatment step of the cross-linking reaction) is performed after applying the coating liquid. There is a need. The film-forming method that requires a post-treatment step for the cross-linking reaction has problems such as an increase in manufacturing steps and a high temperature during the thermal cross-linking reaction, and if the post-treatment step for the cross-linking reaction is unnecessary. , It is practically preferable because a gas barrier film can be obtained by a simpler process.

In Cited Document 2 above, polyamino acids are mentioned as water-insoluble biodegradable resins. However, since polyaspartic acid is a water-soluble biodegradable resin, it is not possible to provide a resin composition using polyaspartic acid having a better gas barrier property from the contents described in Cited Document 2.
Further, in Cited Document 2, a layered clay mineral which has been organically treated is blended in the resin composition. However, it is known that the organically treated layered clay mineral has a reduced packing property of clay, and there is room for improvement from the viewpoint of improving the gas barrier property.

Therefore, the present invention is a resin composition containing polyaspartic acid, which is a biodegradable material, has excellent gas barrier properties, and further requires a post-treatment step of a crosslinking reaction when forming a laminate. It is an object of the present invention to provide a resin composition which does not.

As a result of diligent studies to solve the above problems, the present inventors have found that the above problems can be solved by using a resin composition containing polyaspartic acid and an inorganic component, and the present invention has been made. Has been completed.

That is, the present invention includes the following aspects.
[1] A resin composition containing polyaspartic acid and an inorganic component.
[2] The resin composition according to [1], wherein the inorganic component is a layered clay mineral and / or a metal oxide that has not been organically treated.
[3] The resin composition according to [2], wherein the layered clay mineral contains montmorillonite.
[4] The resin composition according to [2], wherein the metal oxide contains zinc oxide.
[5] When the inorganic component contains the non-organized layered clay mineral, the content of the layered clay mineral is 5 to 70% by mass with respect to the total solid content of the resin composition. , [2] to any one of [4].
[6] When the inorganic component contains the metal oxide, the content of the metal oxide is 10 to 65 mol% with respect to the molar equivalent number of the carboxylic acid group of the polyaspartic acid [2]. ] To [5].
[7] The molded product of the resin composition according to any one of [1] to [6].
[8] A laminate comprising a base material and a coating layer formed by applying the resin composition according to any one of [1] to [6] onto the base material.
[9] The laminate according to [8], which is used as a packaging material.
[10] A gas barrier material containing the resin composition according to any one of [1] to [6].
[11] A coating material containing the resin composition according to any one of [1] to [6].
[12] An adhesive containing the resin composition according to any one of [1] to [6].

According to the present invention, a resin composition containing polyaspartic acid, which is a biodegradable material, has excellent gas barrier properties, and further requires a post-treatment step of a crosslinking reaction when producing a laminate. It is possible to provide a resin composition that does not.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below is an example for explaining the present invention, and the present invention is not limited to these contents.

(Resin composition)
The resin composition of the present invention contains polyaspartic acid and an inorganic component.
Using the resin composition of the present invention, a laminate can be obtained without performing a post-treatment step of a crosslinking reaction. Further, the obtained laminate is excellent in gas barrier property.

<Polyaspartic acid>
Polyaspartic acid is used as the main material of the resin composition, and the resin composition and the laminate formed by using the resin composition have film forming property, water resistance, durability, physical strength, gas barrier property, and biodegradability. Etc. are given.

The polyaspartic acid according to the present invention contains both a free state polyaspartic acid and a salt of polyaspartic acid derived from the free state polyaspartic acid. The salt of polyaspartic acid is not particularly limited, and for example, an alkali metal salt such as a sodium salt or a potassium salt, an organic amine salt such as a diethanolamine salt or a triethanolamine salt, or a basic amino acid salt may be used.

As the polyaspartic acid, polyaspartic acid produced by a conventionally known method can be used. Examples of the method for producing polyaspartic acid include a method of heat-polymerizing aspartic acid.

The content of polyaspartic acid is not particularly limited, but is preferably 30% by mass or more, more preferably 30% by mass or more, based on the total solid content of the resin composition from the viewpoint of biodegradability and moldability. It is 40% by mass or more, more preferably 50% by mass or more, preferably 95% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less.

<Inorganic component>
As the inorganic component according to the present invention, it is preferable to use a layered clay mineral and / or a metal oxide.
In the present invention, at least one of the above as an inorganic component may be contained in the resin composition, and each of them may be contained alone or in combination. When a layered clay mineral and a metal oxide are combined and contained in a resin composition as an inorganic component, the effect of the present invention can be sufficiently exhibited while suppressing the content of a relatively expensive metal oxide.

<< Layered clay minerals >>
The resin composition of the present invention contains a layered clay mineral that is water-dispersible, so that the layered clay mineral is highly dispersed and complexed in the resin, and has excellent gas barrier properties.
Specific examples of layered clay minerals include kaolinite-serpentine clay minerals (haloisite, kaolinite, enderite, dikite, naphthyl, etc., antigolite, chrysotile, etc.), pyrophyllite-talc (pyrophyllite, etc.). Tarku, Kerorai, etc.), Smectite clay minerals (Montmorillonite, Byderite, Nontronite, Saponite, Hectrite, Sauconite, Stevensite, etc.), Vermiculite clay minerals (Vermiculite, etc.), Mica or Mica clay minerals (White mica, gold) Examples include mica such as mica, margarite, tetrasilic mica, teniolite, etc.), green mudstones (cookate, sudowite, clinochloa, chamosite, nimite, etc.). Among these, smectite group clay minerals (hereinafter abbreviated as smectite) are preferable, and montmorillonite is more preferable, from the viewpoint of easy cleavage (peeling) in an aqueous solution. As the layered clay mineral, one kind may be used alone, or a plurality of kinds may be used in combination.

The interlayer cation of the layered clay mineral is not particularly limited and can be appropriately selected according to the type of the layered clay mineral used. For example, smectite may be obtained by exchanging the interlayer cation of smectite (mostly sodium in the case of natural smectite) with lithium ion, ammonium ion, proton or the like. Examples of smectites preferably used in the present invention include sodium-type smectites, lithium-type smectites, ammonium-type smectites, proton-type smectites and the like. It is not particularly limited because it varies depending on the type of smectite used, but from the viewpoint of improving the barrier property, sodium-type smectite and lithium-ion-type smectite are preferable, and lithium-ion-type smectite having a smaller ionic radius is preferable. Tends to be more preferable.

The total of the ammonium ion equivalent, the lithium ion equivalent, and the hydrogen ion equivalent of smectite may be 50 to 120 meq / 100 g. The sum of the ammonium ion equivalent, the lithium ion equivalent, and the hydrogen ion equivalent of smectite may be 50 meq / 100 g or more, 80 meq / 100 g or more, or 100 meq / 100 g or more, and 120 meq / 100 g or less, or 110 meq / 100 g or less. It's okay. The ammonium ion equivalent of smectite is determined by measuring the amount of cations eluted in a 1N potassium chloride solution, and the lithium ion equivalent is determined by measuring the amount of cations eluted in a 1N ammonium acetate solution by ion chromatography. be able to. Further, the hydrogen ion equivalent can be obtained from the difference between the amount of cations before ion exchange and the amount of cations after ion exchange. For example, when montmorillonite whose interlayer ion is sodium is used, the amount of sodium ions eluted from montmorillonite before and after the ion exchange operation into a 1N ammonium acetate solution is measured by ion chromatography, and the hydrogen ion equivalent is measured from the difference. Can be asked.

As a method for exchanging the interlayer cation of smectite with lithium ion, a conventionally known method can also be used. For example, a method of adding a lithium salt such as lithium hydroxide or lithium chloride to a dispersion of natural sodium-type smectite and exchanging cations can be mentioned. By adjusting the amount of lithium added to the dispersion, the amount of lithium ions in the amount of leached cations of the obtained lithium-type smectite can be appropriately adjusted. The lithium-type smectite can also be obtained by a column method or a batch method using a resin in which a cation exchange resin is ion-exchanged with lithium ions.

As the layered clay mineral, a modified layered clay mineral that has been organically treated may be used, but it is more preferable to use a layered clay mineral that has not been organically treated.
Conventionally, layered clay minerals have been blended into resins as fillers for the purpose of improving the heat resistance of resins such as plastics. However, since layered clay minerals having high water dispersibility are hydrophilic, they have a low affinity for hydrophobic resins, and it is difficult to disperse them in the resin as they are and to combine them. Therefore, when the layered clay mineral is compounded with the resin, the layered clay mineral is usually modified by an organic treatment to control the hydrophilicity / hydrophobicity. However, the organically treated layered clay mineral is not suitable from the viewpoint of improving the gas barrier property because the packing property of the clay is lowered. In addition, a separate step for organic treatment is required, which increases the number of manufacturing steps.
Since the resin composition of the present invention contains hydrophilic polyaspartic acid, the layered clay mineral has a high affinity for the resin. Therefore, the layered clay mineral that has not been organically treated can be highly dispersed and compounded in the resin. Therefore, as the layered clay mineral according to the present invention, it is more preferable to use a layered clay mineral that has not been organically treated.

The content of the layered clay mineral is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 20% by mass or more, and particularly preferably 30% by mass or more, based on the total solid content in the resin composition. It is preferably 70% by mass or less, more preferably 60% by mass or less, and further preferably 50% by mass or less. When the content of the layered clay mineral is at least the above lower limit, the water vapor barrier property and the oxygen barrier property (for example, the oxygen barrier property under high humidity) become excellent. On the other hand, when the content of the layered clay mineral is not more than the above upper limit, the formability of the laminated body is excellent and the adhesion to the substrate is improved. In addition, higher gas barrier properties tend to be obtained under high humidity.

<< Metal Oxide >>
The resin composition of the present invention may use a metal oxide as an inorganic component. By mixing polyaspartic acid and a metal oxide in a coating liquid such as water or an aqueous solvent, the carboxylic acid group of polyaspartic acid and the metal oxide are crosslinked in the coating liquid. Therefore, when forming a laminate using the resin composition of the present invention, it is not necessary to separately perform a cross-linking step (post-treatment step of the cross-linking reaction) after applying the coating liquid. Further, the temperature in the crosslinking reaction in the coating liquid is about 20 to 60 ° C., which is lower than the temperature in the post-treatment step of the crosslinking reaction (about 200 ° C. or higher). Therefore, the method for forming a laminate using the resin composition of the present invention is simple and excellent in production efficiency. In addition, the obtained laminate has excellent gas barrier properties.

The metal oxide is not particularly limited as long as it can crosslink the carboxylic acid group of polyaspartic acid, and is, for example, an oxide of an alkaline earth metal (magnesium Mg, calcium Ca, strontium Sr, barium Ba, etc.), Periodic Table 8 Oxides of group metals (iron Fe, ruthenium Ru, etc.), oxides of group 11 metals of the periodic table (copper Cu, etc.), oxides of metals of group 12 of the periodic table (zinc Zn, etc.), metals of group 13 of the periodic table (aluminum Al) Etc.) and other oxides. As the metal oxide, one type may be used alone, or a plurality of types may be used in combination.

Among the above, a metal having a high ionization tendency is preferable from the viewpoint of easily reacting with polyaspartic acid constituting the resin composition, and a divalent metal oxide is preferable from the viewpoint of gas barrier property. The metal oxide according to the present invention is preferably at least one of zinc oxide (ZnO), magnesium oxide (MgO) and calcium oxide (CaO), and zinc oxide is more preferable.

From the viewpoint of obtaining excellent gas barrier properties, it is preferable that the metal oxide is granular and the particle size is small. The particle size of the metal oxide is not particularly limited, but is fine particles having an average particle size of 500 nm or less and 10 nm or more. Particularly preferably, it is fine particles having a diameter of 20 nm to 300 nm. The average particle size here can be measured using a dynamic light scattering type particle size distribution measuring device, for example, LB-500 (manufactured by HORIBA, Ltd.).

The content of the metal oxide is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 20 mol% or more, and particularly preferably 30 mol%, based on the molar equivalent number of the carboxylic acid groups of polyaspartic acid. The above is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less. When the content of the metal oxide is at least the above lower limit, the water vapor barrier property and the oxygen barrier property (for example, the oxygen barrier property under high humidity) become excellent. On the other hand, when the content of the metal oxide is not more than the above upper limit, the formability of the laminate is excellent and the adhesion to the substrate is improved. In addition, higher oxygen barrier properties can be obtained under high humidity.

<Other ingredients>
The resin composition may contain other components in addition to the above-mentioned polyaspartic acid and inorganic components, depending on the intended purpose.

<< Modifier >>
The resin composition may further contain a modifier. Examples of the modifier include a coupling agent, a silane compound, an acid anhydride and the like. When the resin composition contains these modifiers, for example, when the layered clay mineral is contained as an inorganic component, the wettability of the layered clay mineral is improved and the dispersibility in the resin composition is improved. Can be done. As the modifier, one type may be used alone, or a plurality of types may be used in combination.
Examples of the coupling agent include a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent and the like.

<< Solvent >>
The resin composition may contain a solvent depending on the intended use. Examples of the solvent include organic solvents such as methyl ethyl ketone, acetone, ethyl acetate, butyl acetate, toluene, dimethylformamide, acetonitrile, methyl isobutyl ketone, methanol, ethanol, propanol, methoxypropanol, cyclohexanone, methyl cellosolve, ethyl diglycol acetate, and the like. Examples thereof include propylene glycol monomethyl ether acetate. The type and amount of the solvent may be appropriately selected depending on the intended use.

<< Additives >>
The resin composition may contain various additives (excluding the above-mentioned polyaspartic acid, inorganic components, and compounds corresponding to modifiers) as long as the effects of the present invention are not impaired. Additives include, for example, organic fillers, inorganic fillers, stabilizers (antioxidants, heat stabilizers, UV absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, crystal nucleating agents, etc. Examples thereof include oxygen scavengers (compounds having an oxygen scavenging function), tackifiers and the like. These various additives are used alone or in combination of two or more.

<Use of resin composition>
Preferred embodiments of the method of using the resin composition include use in gas barrier materials, coating materials, adhesives and the like. For example, the resin composition of the present invention can be used as a gas barrier material or a coating material.
Further, when the resin composition of the present invention has adhesive performance, it can be used as an adhesive.

<< Gas barrier material >>
Since the resin composition of the present invention is excellent in water vapor barrier property and oxygen barrier property, it can be suitably used as a gas barrier material. The gas barrier material may be any material containing the above-mentioned resin composition.

<< Coating material >>
The resin composition of the present invention can be suitably used as a coating material. The coating material may be any material containing the above resin composition. The form of the coating material is not limited as long as it satisfies various properties as a barrier coating material.
There is no particular limitation on the coating method of the coating material. As a specific method, various coating methods such as roll coating and gravure coating can be exemplified. Further, the coating device is not particularly limited.

<< Adhesive >>
When the resin composition of the present invention has adhesive performance, it can be suitably used as an adhesive. The adhesive may be any one containing the above resin composition. The form of the adhesive is not particularly limited, and it may be a liquid or paste-like adhesive, or it may be a solid adhesive.
Since the resin composition of the present invention has excellent gas barrier properties, this adhesive can be suitably used as an adhesive for gas barriers.

In the case of a liquid or pasty adhesive, it may be a one-component adhesive or a two-component adhesive with a separate curing agent. In the case of a liquid or paste-like adhesive, the method of use is not particularly limited, but it may be applied to one adhesive surface, then the other adhesive surface may be bonded and adhered, and after being injected into the interface of the adhesive surface, the adhesive may be used. It may be glued.
In the case of a solid adhesive, an adhesive formed into a powder, a chip, or a sheet may be placed at the interface of the adhesive surface and thermally melted to adhere and cure.

(Manufacturing method of resin composition)
The resin composition of the present invention is not particularly limited and can be produced according to a conventionally known method. For example, each component is well mixed in water or a water-soluble solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, and methyl ethyl ketone, and then stirred under the conditions of 20 ° C to 60 ° C for about 0.1 to 24 hours. And so on.

(Molded body)
The molded product of the present invention can be obtained by molding the above-mentioned resin composition. The molding method is arbitrary and may be selected in a timely manner depending on the intended use. The molded product may be made of a resin composition or may be made of a cured product of the resin composition. Further, as long as the molded body is formed by molding a resin composition, there is no particular limitation on whether or not the molded body itself is a self-supporting film. The shape of the molded body is not limited, and may be, for example, a plate or sheet having a film thickness of more than 250 μm, or a film having a film thickness of 250 μm or less, and has a three-dimensional shape. It may be coated on a base material, or may be molded in a form existing between the base materials.

When producing a plate-shaped or sheet-shaped molded body, the resin composition is molded by using, for example, an extrusion molding method, a flat press, a deformed extrusion molding method, a blow molding method, a compression molding method, a vacuum molding method, an injection molding method, or the like. There is a way to do it. When producing a film-shaped molded product, for example, melt extrusion method, solution casting method, inflation film molding, cast molding, extrusion lamination molding, calendar molding, sheet molding, fiber molding, blow molding, injection molding, rotation molding, Coating molding can be mentioned. When the resin composition is cured by heat or active energy rays, the resin composition may be molded by using various curing methods using heat or active energy rays.

If the resin composition is liquid, it may be molded by coating. Examples of the coating method include a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, a doctor blade method, a curtain coating method, a slit coating method, a screen printing method, an inkjet method, and a dispense method. Can be mentioned.

The molded product of the present invention exhibits excellent gas barrier properties (water vapor barrier properties and oxygen barrier properties). In particular, the molded product of the present invention is excellent in oxygen barrier property, especially in the medium humidity range (barrier measurement under 75% humidity RH condition).
The oxygen permeability of the molded product under a humidity of 75% RH condition is preferably 15 cc / m ² / day / atm or less, more preferably 5 cc / m ² / day / atm or less, still more preferably 2 cc / m ² . It is less than / day / atm.

(Laminated body)
A preferred embodiment using the resin composition of the present invention includes a laminate having a coating layer containing the above-mentioned resin composition on a substrate.
The laminated body may have a two-layer structure or may have a three-layer structure or more.

The material of the base material is not particularly limited and may be appropriately selected depending on the intended use. Examples thereof include wood, metal, resin film, paper, silicon, modified silicon and the like, and a base material obtained by joining different materials. It may be. The shape of the base material is not particularly limited, and may be any shape depending on the purpose, such as a flat plate, a sheet shape, or a three-dimensional shape having a curvature on the entire surface or a part thereof. Further, there are no restrictions on the hardness, transparency, etc. of the base material.

When a resin film is used as the base material, the resin film to be used may be appropriately selected according to the purpose. For example, when used as a packaging material, the outermost layer is a thermoplastic resin film selected from polyethylene terephthalate (hereinafter abbreviated as PET), biaxially stretched polypropylene (hereinafter abbreviated as OPP), and polyamide, and the innermost layer is unstretched. A composite film consisting of two layers using a thermoplastic resin film selected from polypropylene (hereinafter abbreviated as CPP) and a low-density polyethylene film (hereinafter abbreviated as LLDPE), or an outermost layer selected from, for example, PET, polyamide, and OPP. It consists of three layers using a thermoplastic resin film to be formed, a thermoplastic resin film to form an intermediate layer selected from OPP, PET and polyamide, and a thermoplastic resin film to form an innermost layer selected from CPP and LLDPE. Examples thereof include a composite film and a film having more layers than this. In particular, in the case of PET film, when PET using ethylene glycol based on a non-petroleum-derived raw material is used as a raw material, the plant-derived content of the entire laminate can be increased, and the laminate is more environmentally friendly. It is especially preferable because you can get a body. Further, the surface of the laminate may be subjected to various surface treatments such as flame treatment and corona discharge treatment, if necessary, so that an adhesive layer without defects such as film breakage and repelling is formed.

The thickness of the base material is not particularly limited and is appropriately selected depending on the intended use of the laminate of the present invention, but is preferably 0. It is 1 to 500 μm, more preferably 1 to 300 μm, and even more preferably 10 to 200 μm.

The thickness of the coating layer is not particularly limited and is appropriately selected depending on the application in which the laminate of the present invention is used, but from the viewpoint of more reliably obtaining the gas barrier property of the laminate, it is 0.05 μm or more. It is preferable to do so. The upper limit of the thickness of the coating layer is not particularly limited, but is preferably about 0.5 to 5 μm from the viewpoint of economic efficiency and the like.

The laminate of the present invention exhibits excellent gas barrier properties (water vapor barrier properties and oxygen barrier properties). In particular, the laminate of the present invention is excellent in oxygen barrier property, especially in the medium humidity range (barrier measurement under 75% humidity RH condition). The oxygen permeability of the laminate under 75% RH humidity conditions is preferably 15 cc / m ² / day / atm or less, more preferably 5 cc / m ² / day / atm or less, still more preferably 2 cc / m ² . It is less than / day / atm.

<Manufacturing method of laminated body>
The laminate may be provided with a coating layer containing the above-mentioned resin composition, and the coating layer may be formed by direct coating or direct molding on the substrate, or the molded body of the resin composition may be laminated. May be good.
In the case of direct application, the application method is not particularly limited, and the spray method, spin coating method, dip method, roll coating method, blade coating method, doctor roll method, doctor blade method, curtain coating method, slit coating method, screen printing Examples include the method and the inkjet method. In the case of direct molding, in-mold molding, insert molding, vacuum forming, extrusion laminating molding, press molding and the like can be mentioned.
Further, the laminate may be obtained by applying a substrate precursor to a cured product of the resin composition and curing it, and the substrate precursor or the resin composition is in an uncured or semi-cured state. It may be obtained by curing after adhering with. The precursor of the base material is not particularly limited, and examples thereof include various curable resin compositions.
Further, the resin composition of the present invention does not require a post-treatment step of a crosslinking reaction when forming a laminate. When the resin composition of the present invention is used, a laminate can be obtained in a simpler process.

In the present invention, in order to impart even higher gas barrier properties, a film in which a vapor-deposited layer of a metal such as aluminum or a metal oxide such as silica or alumina is laminated, polyvinyl alcohol, or ethylene / vinyl alcohol are used together. A barrier film containing a gas barrier layer such as a polymer or vinylidene chloride can be used in combination to impart higher gas barrier properties. Above all, by using a film provided with a thin-film film of a metal oxide such as aluminum, silica, or alumina (so-called thin-film film) in combination with the laminate of the present invention, the coating layer is reinforced to impart extremely high gas barrier properties. Can be done.

<Types of gas components that can block permeation>
Gases that can be blocked by the laminate of the present invention include oxygen, inert gases such as carbon dioxide, nitrogen and argon, alcohol components such as methanol, ethanol and propanol, phenols such as phenol and cresol, and low molecules. Examples thereof include aroma components composed of compounds such as soy sauce, sauce, miso, lemonen, menthol, methyl salicylate, coffee, cocoa shampoo, and rinse.

<Application of laminated body and molded body>
The laminate of the present invention provided with the resin composition of the present invention on a substrate and the molded body of the present invention obtained by molding the resin composition of the present invention are excellent in gas barrier properties, particularly oxygen barrier properties. It can be suitably used in various fields such as electric / electronic parts, automobile parts, mechanical parts, and structural parts.
It can also be applied to packaging applications such as foods, pharmaceuticals, and electronic members.
Preferred embodiments of applying the laminate include, for example, packaging materials and barrier paper.

<< Packaging material >>
The resin composition of the present invention and the laminate having the resin composition can be used as a packaging material used for packaging foods and the like.
Packaging materials used for packaging foods and the like are required to have functions such as protection of contents, retort resistance, heat resistance, transparency, and processability. The gas barrier function is especially important for maintaining the quality of the contents.
By utilizing the laminate of the present invention, it is possible to provide a packaging material having excellent gas barrier properties (particularly oxygen barrier properties).

<< Barrier paper >>
The laminate of the present invention can be used as a barrier paper as a paper material having a barrier property.
For example, a barrier paper having a coating layer formed on a paper substrate by coating or impregnating the paper substrate in the form of an aqueous solution or an aqueous dispersion of a resin composition shall be applied to various paper sheets and paper containers. Can be done.
For example, it can be used as a barrier paper as a paper packaging material for acceptable foods such as dry food and coffee, or as a barrier paper as a paper packaging material for non-appropriate foods such as powder detergent.
As a method for applying or impregnating an aqueous solution, an aqueous emulsion, or an aqueous dispersion containing the resin composition of the present invention on a paper substrate, for example, air knife coating, bar coating, roll coating, gravure coating, cast coating, blade Examples include coating, gate roll coating, kiss roll coating, dipping method, spray coating and the like. Using the above method, the resin composition of the present invention can be applied to or impregnated into a paper substrate, and further, for example, by impregnating with a size press, the inside of the paper substrate can be impregnated.

Hereinafter, the present invention will be specifically described with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the present invention is not limited to the following examples.

(Production example of porris succinimide)
100 parts of L-aspartic acid (manufactured by Jiangsu Qiancheng Bio-Engineering Co. Ltd.), 10 parts of 85% phosphoric acid, 224 parts of mesitylene in a four-necked flask equipped with a stirrer. , And 96 parts of sulfolan.
Under normal pressure, the temperature was raised to 150 to 160 ° C. and held for 5 hours to carry out a polycondensation reaction. The water generated during the reaction was further heated to 170 ° C. and distilled off the system. After completion of the reaction, the reaction solution was filtered to obtain a reaction product.
The obtained product was washed 4 times with 400 parts of distilled water and then dried under reduced pressure at 80 ° C. for 24 hours to obtain 72 parts of porris succinimide powder. When the polystyrene-equivalent molecular weight of the obtained succinimide was determined by GPC measurement, the weight average molecular weight was 64,000.

(Production example of polyaspartic acid)
100 parts of porris succinimide obtained in the above production example was slurried in 450 parts of distilled water (concentration 18 wt%). 500 parts of 2N-NaOH (1.0 eq with respect to porris succinimide) was added dropwise to this slurry over 6 hours. Then, the NaOH-treated liquid of the porris succinimide was put into a liquid containing 1000 parts of an ion exchange resin (Amberlite IR120B-H manufactured by Organo Corporation) in 1700 parts of distilled water. After stirring and holding for about 30 minutes, the ion exchange resin was separated by filtration and freeze-dried to obtain a powder of polyaspartic acid. From the acid value measurement of polyaspartic acid, the acid value was 470 mg-KOH / g. The weight average molecular weight of polyaspartic acid was 100,000.
The acid value was measured according to the acid value measuring method described in JIS-K0070.

(Preparation example of ZnO dispersion)
ZnO (manufactured by Sakai Chemical Industry Co., Ltd., FINEX-50) with a primary particle diameter of 20 nm and distilled water: 700 g are mixed, and the diameter is 0.3 mm in a bead mill (manufactured by Ashizawa Finetech Co., Ltd .: Labostar Mini LMZ015). After dispersion treatment using the zirconia beads of No. 1 for 1 hour, the beads were sieved to obtain a ZnO dispersion having a solid content concentration of 30%. The particle size of ZnO in this dispersion was 88 nm.

<Example 1>
To 100 parts of the aqueous solution of polyaspartic acid (concentration 14.3% by weight) obtained in the production example, 280 parts of an aqueous dispersion (concentration 4%) of sodium-type montmorillonite (Kunipia F manufactured by Kunimine Industry Co., Ltd.) was added. The mixture was stirred and held for 1 hour to prepare a coating liquid. Apply this coating solution to the corona-treated surface of a 12 μm PET film (E-5100 manufactured by Toyobo Co., Ltd.) using a bar coater so that the coating thickness becomes 2 μm after drying, and immediately after coating, a dryer at 80 ° C. It was heat-treated in it for 2 minutes. As a result, a molded body of each resin composition was formed on the PET film, and the laminated film (laminated body) of Example 1 was obtained. The montmorillonite content at this time is 44 wt% with respect to the total solid content.
In order to evaluate the gas barrier property of the laminated film, the oxygen permeability was measured.
The oxygen permeability is measured according to JIS-K7126 (isopressure method) at a temperature of 23 ° C, 0% RH, and using an oxygen permeability measuring device "OX-TRAN1 / 50" manufactured by MOCON. The test was carried out at a temperature of 23 ° C. and an atmosphere of 75% RH. In addition, RH represents relative humidity.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 2>
In Example 1, 280 parts of an aqueous dispersion (concentration 4%) of sodium-type montmorillonite (Kunipia F, manufactured by Kunimine Industry Co., Ltd.) was used as an aqueous dispersion (concentration) of lithium-type montmorillonite (Kunipia M, manufactured by Kunimine Industry Co., Ltd.). 4%) The laminated film of Example 2 was obtained by the same method except that it was changed to 280 parts. The montmorillonite content at this time is 44 wt% with respect to the total solid content.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 3>
In Example 1, an aqueous dispersion (concentration 4%) of sodium-type montmorillonite (Kunipia F, manufactured by Kunimine Industry Co., Ltd.) and an aqueous dispersion (concentration 4%) of lithium-type montmorillonite (Kunipia M, manufactured by Kunimine Industry Co., Ltd.) were used. ) The laminated film of Example 3 was obtained by the same method except that it was changed to 154 parts. The montmorillonite content at this time is 30 wt% with respect to the total solid content.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 4>
In Example 1, an aqueous dispersion (concentration 4%) of sodium-type montmorillonite (Kunipia F, manufactured by Kunimine Industry Co., Ltd.) and an aqueous dispersion (concentration 4%) of lithium-type montmorillonite (Kunipia M, manufactured by Kunimine Industry Co., Ltd.) were used. ) The laminated film of Example 4 was obtained by the same method except that it was changed to 357 parts. The montmorillonite content at this time is 50 wt% with respect to the total solid content.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 5>
Seven parts of the ZnO dispersion (concentration: 30 wt%) obtained in the preparation example was mixed with 100 parts of an aqueous solution of polyaspartic acid (concentration: 10% by weight), and the mixture was stirred and held for 30 minutes to prepare a coating liquid. Apply this coating solution to the corona-treated surface of a 12 μm PET film (E-5100 manufactured by Toyobo Co., Ltd.) using a bar coater so that the coating thickness becomes 2 μm after drying, and immediately after coating, a dryer at 80 ° C. It was heat-treated in it for 2 minutes. As a result, a molded body of each resin composition was formed on the PET film, and the laminated film of Example 5 was obtained. The ZnO content at this time is 60 mol% with respect to the carboxylic acid group of polyaspartic acid.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 6>
3.5 parts of the ZnO dispersion (concentration: 30 wt%) obtained in the preparation example was mixed with 100 parts of an aqueous solution of polyaspartic acid (concentration: 10% by weight), and the mixture was stirred and held for 30 minutes, and then sodium-type montmorillonite (concentration: 30 wt%). 3 parts of Kunipia F) powder manufactured by Kunimine Kogyo Co., Ltd. was slowly added and stirred and held for 3 hours to prepare a uniformly dispersed coating liquid. Apply this coating solution to the corona-treated surface of a 12 μm PET film (E-5100 manufactured by Toyobo Co., Ltd.) using a bar coater so that the coating thickness becomes 2 μm after drying, and immediately after coating, a dryer at 80 ° C. It was heat-treated in it for 2 minutes. As a result, a molded body of each resin composition was formed on the PET film, and the laminated film of Example 6 was obtained. The montmorillonite content at this time is 21 wt% with respect to the total solid content, and the ZnO content is 30 mol% with respect to the carboxylic acid group of polyaspartic acid.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Example 7>
In Example 6, the same method was used except that 3 parts of sodium-type montmorillonite (Kunipia F, manufactured by Kunimine Industry Co., Ltd.) was changed to 1 part of lithium-type montmorillonite (Kunipia M, manufactured by Kunimine Industry Co., Ltd.). , The laminated film of Example 7 was obtained. The montmorillonite content at this time is 8 wt% with respect to the total solid content, and the ZnO content is 30 mol% with respect to the carboxylic acid group of polyaspartic acid.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

<Comparative Example 1>
An aqueous solution of polyaspartic acid (concentration 14.3% by weight) obtained in the production example was used as a coating liquid, and a 12 μm PET film (E-5100 manufactured by Toyobo Co., Ltd.) was dried using a bar coater on the corona-treated surface. The coating was applied so that the coating thickness was 2 μm, and immediately after the coating, heat treatment was performed in a dryer at 80 ° C. for 2 minutes. As a result, a molded product of each resin composition was formed on the PET film, and the laminated film of Comparative Example 1 was obtained.
The measurement results of the oxygen permeability of the obtained laminated film are shown in Table 1 below.

From the results of the oxygen permeability of the laminated films of Examples 1 to 7, the laminated film formed by using the resin composition according to the present invention exhibits excellent oxygen barrier properties (particularly oxygen barrier properties in the medium humidity range). Was confirmed. On the other hand, the laminated film of Comparative Example 1 containing no inorganic component according to the present invention was inferior in oxygen barrier property in the medium humidity range.
Further, the laminated films of Examples 1 to 4 do not require a cross-linking step when forming the laminated film, and the laminated film can be formed by a simple step. Further, in the laminated films of Examples 5 to 7, a crosslinked structure is formed in the coating liquid under low temperature conditions when forming the laminated film. Therefore, in the laminated films of Examples 5 to 7, it is not necessary to separately perform a cross-linking step (post-treatment step of the cross-linking reaction) after applying the coating liquid, and the laminated film can be formed by a simple step. Is.

Claims

A resin composition containing polyaspartic acid and an inorganic component.
The resin composition according to claim 1, wherein the inorganic component is a layered clay mineral and / or a metal oxide that has not been organically treated.
The resin composition according to claim 2, wherein the layered clay mineral contains montmorillonite.
The resin composition according to claim 2, wherein the metal oxide contains zinc oxide.
When the inorganic component contains the unorganized layered clay mineral,
The resin composition according to any one of claims 2 to 4, wherein the content of the layered clay mineral is 5 to 70% by mass with respect to the total solid content of the resin composition.
When the inorganic component contains the metal oxide,
The resin composition according to any one of claims 2 to 5, wherein the content of the metal oxide is 10 to 65 mol% with respect to the molar equivalent number of the carboxylic acid group of the polyaspartic acid.
A molded product of the resin composition according to any one of claims 1 to 6.
A laminate comprising a base material and a coating layer obtained by applying the resin composition according to any one of claims 1 to 6 onto the base material.
The laminate according to claim 8, which is used as a packaging material.
A gas barrier material containing the resin composition according to any one of claims 1 to 6.
A coating material containing the resin composition according to any one of claims 1 to 6.
An adhesive containing the resin composition according to any one of claims 1 to 6.