JPH11314674A - Gas barrier container, and packaging material for food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give excellent gas barrier property to a preliminarily formed container, and to enable the recycling after the use. SOLUTION: In a packaging material, an anchor layer is preferably laminated on a preliminarily formed container, and further, a gas barrier layer having the resin composition containing inorganic compounds is laminated preferably by a coating method. The container is preferably formed by a blow molding method, a vacuum molding method, or a compressed air molding method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a gas barrier container which is excellent in gas barrier properties and can store contents such as food which easily deteriorates when exposed to the outside air for a good and long time, and this gas barrier container. It relates to a packaging material for food.

[0002]

2. Description of the Related Art Conventionally, containers having gas barrier properties (hereinafter referred to as gas barrier containers) have been used in order to prevent the stored / packaged contents from coming into contact with the outside air as much as possible. Such a gas barrier container is usually obtained by molding a laminate having a layer having gas barrier properties.

Various methods are used for producing such a gas barrier container. For example, the gas barrier container can be produced by an extrusion molding method in which a gas barrier resin and polypropylene are co-extruded.

[0004] The extrusion molding method is a processing method having a very wide range of applications, and includes various processes such as a rod-shaped or tubular molded product, a film-shaped or sheet-shaped molded product, bonding with paper, metal foil, and resin film. It can be used for manufacturing molded products. Therefore, it is very widely used in the production of molded articles, including the production of gas barrier containers.

[0005]

However, in the gas barrier container obtained by the extrusion molding (co-extrusion) as described above, the melting of the resin layer as the gas barrier layer and the other constituent layers of the laminate such as the base material or the like is difficult. Since the physical properties often do not match, there is a problem that good molding cannot be performed.

Further, the gas barrier layer of a gas barrier container (laminated body) is usually considerably thick because the resin layer serving as a gas barrier layer cannot exhibit gas barrier properties unless it has a certain thickness. It is difficult for the gas barrier layer to be almost completely separated from other components of the laminate, such as a substrate. Therefore, when disposing of the used gas barrier container, the gas barrier container contains a large amount of different kinds of materials (resin to be a gas barrier layer), which causes a problem of reducing recyclability.

[0007] Therefore, there has been a demand for a gas barrier container which imparts good gas barrier properties to a container obtained in advance by extrusion molding or the like and enables recycling after use.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that a coating liquid comprising a resin composition having an inorganic layered compound is preferably applied to the inner surface of a preformed container. It has been found that a gas barrier container exhibiting good gas barrier properties can be obtained by coating with a coating, and the present invention has been completed.

That is, in the gas barrier container of the present invention, in order to solve the above-mentioned problem, a gas barrier layer made of a resin composition having an inorganic layered compound is laminated on an inner surface of a preformed container. It is characterized by.

According to the above construction, the gas barrier layer made of the resin composition having the inorganic layered compound is formed on the preformed container, so that the container has a different shape than usual. However, excellent gas barrier properties can be imparted. Further, since the gas barrier layer has the inorganic layered compound as described above, it can exhibit excellent impact resistance even in comparison with various layers which are conventionally formed later. Furthermore, since the formed gas barrier layer is a thin film, recycling after using the gas barrier container can be facilitated.

The gas barrier layer is preferably laminated by coating a coating liquid comprising a resin composition having an inorganic layered compound. Thereby, the gas barrier layer can be formed more uniformly and easily.

The material of the container in which the gas barrier layer is formed can be paper or resin, but is not particularly limited. In the case of a resin, it may be foamed. The molding method is preferably a resin molding method by any one of a blow molding method, a vacuum molding method, a pressure molding method, an injection molding method, and a press molding method.
Specific molded products include, for example, squeeze bottles used for packaging of mayonnaise, ketchup, dressing, and the like, and liquid filling tanks for storing and packaging liquids. However, the type and shape of the container are not limited to those obtained by these molding methods.

[0013] Oxygen permeability of the gas barrier container according to the present invention it is more preferable that it has preferably, equal to or less than 0.1mL / m ² · day · atm that is equal to or less than 1mL / m ² · day · atm , 0.05mL / m ² · day ·
More preferably, it is atm or less. When the oxygen permeability is within this range, deterioration of the stored and packaged contents can be suppressed, and the contents can be held for a longer period.

In the gas barrier container according to the present invention, the inorganic layered compound is preferably swelled and cleaved in a dispersion medium. The gas barrier layer is obtained by subjecting a mixed solution of a resin composition having an inorganic layered compound to high pressure dispersion treatment. It is preferably obtained. The pressure conditions for the high-pressure dispersion treatment are as follows:
It is preferably at least 100 kgf / cm ² ,
0 kgf / cm ² or more, more preferably 1 kgf / cm ² or more.
It is particularly preferred that it is not less than 000 kgf / cm ² .

Further, the aspect ratio of the inorganic layered compound is as follows:
It is preferably in the range of 50 to 5000, and more preferably in the range of 200 to 3000.

The resin composition preferably contains a high hydrogen bonding resin. At this time, the weight ratio between the inorganic layered compound and the high hydrogen bonding resin is (1/100) to
(100/1), preferably (1/1).
More preferably, it is in the range of 20) to (10/1). Further, the high hydrogen bonding resin preferably has a molar percentage of hydrogen bonding group or ionic group per unit weight of the resin of 30% or more and 50% or less. It is preferable that the product is a polysaccharide, a polysaccharide, or an ethylene-vinyl alcohol copolymer and a modified product thereof.

By providing each of these components, the gas barrier property of the container can be further improved, and the deterioration of the contents can be suppressed more effectively.

[0018] A food packaging material according to the present invention is characterized in that it comprises a gas barrier container having the above-described configuration. Therefore, it is possible to provide a food packaging material capable of preserving the contents for a long period of time, and to form a gas barrier layer later. , A food packaging material having a high degree of freedom such that a gas barrier layer is appropriately formed can be obtained.

[0019]

FIG. 1 shows an embodiment of the present invention.
The following is a description based on FIG.
The gas barrier container according to the present invention is obtained by laminating a gas barrier layer having an inorganic layered compound on the inner surface of a preformed container.

The inorganic layered compound used in the gas barrier layer is an inorganic compound having a layered structure in which unit crystal layers are stacked on each other, and when cleaved, the particle size is 5 μm or less, and the aspect ratio is gas barrier. The property is not particularly limited as long as the aspect ratio is in the range of 200 to 3,000, more preferably in the range of 200 to 3,000.

When the aspect ratio is less than 50, the gas barrier property is not sufficient, and when the aspect ratio is more than 5000, it is technically difficult and economically expensive. Further, when the particle size is 3 μm or less, the transparency becomes better, and when the particle size is 1 μm or less, it is more preferable for applications in which transparency is important.

Specific examples of the above-mentioned inorganic layered compound include graphite, phosphate derivative type compounds (such as zirconium phosphate type compounds), chalcogenides, and clay minerals. Here, the “chalcogen compound” includes a group IV (Ti, Zr, Hf) and a group V (V, Nb, T).
a) and dichalcogenides of group VI (Mo, W), wherein the compound is of the formula MX ₂ (M is the above element, X is the chalcogen (S,
Se, Te). ).

The particle size of the above-mentioned inorganic layered compound means a particle size obtained by a diffraction / scattering method in a dispersion medium. It is extremely difficult to measure the true particle size in the gas barrier layer.
In the case where the dispersion medium of the same kind as the dispersion medium used in the scattering method is sufficiently swollen and cleaved to be combined with the resin used for the gas barrier layer, the cleaved unit crystal layer in the resin 32 of the gas barrier layer 3 shown in FIG. The particle size of 31 can be considered to correspond to the particle size of the cleaved inorganic layered compound in the dispersion medium.

[Method for Determining Average Particle Diameter] Methods for determining the average particle diameter of particles in a liquid include a method based on a diffraction / scattering method, a method based on a dynamic light scattering method, a method based on a change in electric resistance, and a method using an underwater microscope. A method by image processing or the like is possible.

In the dynamic light scattering method, when the resin and the particles coexist, the apparent liquid viscosity is different from that of the pure dispersion medium, so that it is difficult to evaluate the method. There is a problem of resolution in the method using image processing after photographing in a submerged microscope, and each method is difficult to use.

In the method based on the diffraction / scattering method, when a resin solution, for example, an aqueous resin solution has substantially little scattering (transparency), and scattering originating from the particles is dominant, the particles are dispersed regardless of the presence or absence of the resin. It is preferable because information on only the particle size distribution can be obtained.

[Measurement of Average Particle Size by Diffraction / Scattering Method] The particle size distribution and average particle size measurement by the diffraction / scattering method are carried out by irradiating a dispersion obtained by dispersing a swollen and cleaved inorganic layered compound in an aqueous dispersion medium. The diffraction / scattering pattern obtained when the light is allowed to pass through is calculated by using the Mie scattering theory or the like to calculate the most consistent particle size distribution of the pattern.

As a commercially available device, a particle size measuring device (LS230, LS200, L
S100, manufactured by Coulter Co., Ltd.), laser diffraction particle size distribution analyzer (SALD2000, SALD2000A, S
ALD3000, manufactured by Shimadzu Corporation) Laser diffraction / scattering type particle size distribution analyzer (LA910, LA700, LA5)
00, manufactured by Horiba and Microtrack SP
A, Microtrack FRA, manufactured by Nikkiso Co., Ltd.).

[Aspect Ratio Measurement Method] The aspect ratio (Z) is a ratio obtained from the relationship of Z = L / a. Here, L is the particle diameter (volume-based median diameter) of the inorganic layered compound in the dispersion obtained by the particle diameter measurement method by the above-mentioned diffraction / scattering method, and a is the cleaved unit shown in FIG. This is the unit thickness of the crystal layer 31. The “unit thickness a” is a value determined based on the result of independently measuring the thickness of the inorganic layered compound by a powder X-ray diffraction method described later or the like.

More specifically, as schematically shown in the graph of FIG. 2 in which 2θ is on the horizontal axis and the intensity of the X-ray diffraction peak is on the vertical axis, the lowest peak of the observed diffraction peaks is shown. From the angle θ corresponding to the peak, the Bragg equation (nλ = 2Dsi
The interval determined based on nθ, n = 1, 2, 3,... is defined as “unit thickness a” (for details of the powder X-ray diffraction method, for example, see “ Guide (a) ”, page 69 (1985) published by Kagaku Dojinsha).

When the resin composition corresponding to the gas barrier layer 3 obtained by removing the dispersion medium from the dispersion is subjected to powder X-ray diffraction, usually, the plane spacing of each of the dispersed inorganic layered compounds in the resin composition is determined. Can be obtained as the surface distance d shown in FIG.

More specifically, as shown schematically in the graph of FIG. 3 in which the horizontal axis indicates 2θ and the vertical axis indicates the intensity of the X-ray diffraction peak, the diffraction corresponding to the above “unit thickness a” is shown. Of the diffraction peaks observed at a lower angle (larger interval) than the peak position, the interval corresponding to the peak at the lowest angle is defined as “plane interval d” (a <d).

As schematically shown in the graph of FIG. 4, when it is difficult to detect the peak corresponding to the above-mentioned "surface distance d" by overlapping with a halo (or background), the angle lower than 2θd is used. The area of the portion excluding the baseline is set as the peak corresponding to the “surface distance d”.
Here, “θd” is a diffraction angle corresponding to “(unit thickness a) + (width of single resin chain)” (for details of the method of calculating the surface distance d, see, for example, Shuichi Iwami et al. Ed., "Encyclopedia of Clay", p. 35 or less and p. 271 or less, 1985
Year, see Asakura Shoten Co., Ltd.).

Usually, the difference between the above-mentioned surface distance d and "unit thickness a", that is, the value of k = (da) (when converted to "length") constitutes the resin composition. It is equal to or greater than the width of a single resin chain [k = (da) ≧ width of a single resin chain]. Such “width of a single resin chain” can be determined by simulation calculation or the like (for example, “Introduction to Polymer Chemistry”, pp. 103-110,
1981, see Chemical Doujinshi), and in the case of polyvinyl alcohol, it is 4 to 5 angstroms (2 to 3 angstroms for water molecules).

It is extremely difficult to directly measure the "true aspect ratio" of the unit crystal layer 31 in the gas barrier layer 3. Although the above aspect ratio Z = L / a is not always equal to the “true aspect ratio” of the unit crystal layer 31 in the gas barrier layer 3, the aspect ratio Z is “true” for the following reason. It is reasonable to approximate the "aspect ratio".

There is a relation of a <d between the plane spacing d of the resin composition obtained by the powder X-ray diffraction method and the “unit thickness a” obtained by the powder X-ray diffraction measurement of the inorganic layered compound alone. And the value of (da) is the value of resin 1 in the composition.
If the width of the main chain or more, in the resin composition,
The resin is inserted between the layers of each inorganic layered compound. Therefore, the unit crystal layer 31 in the gas barrier layer 3
Is approximated by the above “unit thickness a”, that is, the “true aspect ratio” of the unit crystal layer 31 in the gas barrier layer 3 is referred to as the “aspect ratio Z” in the dispersion of the inorganic layered compound. There is sufficient validity to approximate with.

As described above, although it is extremely difficult to measure the true grain size of the unit crystal layer 31 in the gas barrier layer 3, the unit crystal layer 31 in the resin 32 of the gas barrier layer 3 is extremely difficult.
Is the particle size of the dispersion liquid (resin / inorganic layered compound / dispersion medium)
Can be considered to correspond to the particle size L of the inorganic layered compound.

However, the particle diameter L in the dispersion obtained by the diffraction / scattering method is considered to be very unlikely to exceed the major axis Lmax of the inorganic layered compound, so that the true aspect ratio (Lmax / a) is low. The possibility that the ratio is lower than the “aspect ratio Z” used in the present invention (Lmax / a <Z) is theoretically considerably low.

From the above two points, it is considered that the definition Z of the aspect ratio used in the present invention has sufficient validity. In the present specification, “aspect ratio” or “particle size” means “aspect ratio Z” defined above or “particle size L determined by a diffraction / scattering method”.

From the viewpoint of easily giving a large aspect ratio, an inorganic layered compound having a property of swelling and cleaving in a dispersion medium is preferably used.

The swelling of the inorganic layered compound in the dispersion medium
The degree of "cleavage" can be evaluated by the following "swelling / cleavage" test. The swellability of the inorganic layered compound is
In the following swellability test, the swelling value is preferably about 5 or more (more preferably, about 20 or more). On the other hand, the cleavage property of the inorganic layered compound is preferably about 5 or more (and more preferably about 20 or more) in the cleavage test. In these cases, a liquid having a density smaller than the density of the inorganic layered compound is used as the dispersion medium. When the inorganic layered compound is a natural swellable clay mineral, it is preferable to use water as the dispersion medium.

<Swelling test> 100 mL of the dispersion medium was placed in a 100 mL measuring cylinder, and 2 g of the inorganic layered compound was added thereto.
Add slowly. After standing, the volume (mL) of the inorganic layered compound dispersed layer is read as the swelling value from the scale at the interface between the inorganic layered compound dispersed layer and the supernatant after 24 hours at 23 ° C. The larger the value, the higher the swelling property.

<Cleaving test> 30 g of an inorganic layered compound was slowly added to 1500 mL of a dispersion medium, and a dispersing machine [Despa MH-L, manufactured by Asada Tekko Co., Ltd., blade diameter 52 mm, rotation speed 3]
100 rpm, container capacity 3 L, distance 28 between bottom and blade
mm] at a peripheral speed of 8.5 m / sec for 90 minutes (23 ° C.), take 100 mL of the dispersion liquid, put it in a graduated cylinder and let stand for 60 minutes, and then, from the interface with the supernatant, the volume of the inorganic layered compound dispersed layer Read (mL) as cleavage value.

As the inorganic layered compound which swells and cleaves in the dispersion medium, a clay mineral which swells and cleaves in the dispersion medium is particularly preferably used. Such clay minerals are generally
On the top of the tetrahedral layer of silica, a two-layer structure with an octahedral layer with aluminum or magnesium as the central metal, and on an octahedral layer with a silica tetrahedral layer with aluminum or magnesium as the central metal Is classified into a type having a three-layer structure in which is narrowed from both sides. The former two-layer structure type includes a kaolinite group and an antigolite group, and the latter three-layer structure type includes a smectite group and a smectite group depending on the number of interlayer cations.
Vermiculite, mica and the like can be mentioned.

As these clay minerals, more specifically, kaolinite, dickite, nacrite, halloysite, antigolite, chrysotile, pyrophyllite, montmorillonite, beidellite, nontronite, saponite, sauconite, stevensite, hectite Light, tetrasilicyl mica, sodium teniolite, muscovite, margarite, talc, vermiculite, phlogopite, zansophyllite, chlorite and the like can be mentioned.

A clay mineral treated with an organic substance (hereinafter sometimes referred to as an organically modified clay mineral) can also be used as an inorganic layered compound. See Clay Encyclopedia).

Among the above clay minerals, smectites, vermiculites, and micas are preferable, and smectites are more preferable from the viewpoint of swelling or cleavage. Examples of the smectite group include montmorillonite, beidellite, nontronite, saponite, sauconite, stevensite, and hectorite.

The dispersion medium for swelling or cleaving the inorganic layered compound is, for example, water,
Examples include alcohols such as methanol, ethanol, propanol, isopropanol, ethylene glycol and diethylene glycol, dimethylformamide, dimethyl sulfoxide, and acetone, and more preferably alcohols such as water and methanol.

In the case of organically modified clay minerals, aromatic hydrocarbons such as benzene, toluene and xylene; ethers such as ethyl ether and tetrahydrofuran; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; n-pentane; Aliphatic hydrocarbons such as n-hexane and n-octane; halogenated hydrocarbons such as chlorobenzene, carbon tetrachloride, chloroform, dichloromethane, 1,2-dichloroethane and perchloroethylene; ethyl acetate; methyl methacrylate ( MMA), dioctyl phthalate (DOP), dimethylformamide,
Examples include dimethyl sulfoxide, methyl cellosolve, and silicone oil.

The gas barrier container according to the present invention is obtained by laminating the gas barrier layer 3 made of the resin composition containing the above-mentioned inorganic layered compound on a container previously molded into a desired shape. The method for laminating the gas barrier layer 3 is not particularly limited. However, in order to laminate the thinner gas barrier layer 3 effectively, a method of preparing a coating liquid composed of the resin composition containing the inorganic layered compound and coating the coating liquid is very suitably used. Can be.

The resin contained in the above-mentioned coating liquid is not particularly limited. For example, polyolefin resin, polyester resin, amide resin, acrylic resin, styrene resin, acrylonitrile resin, cellulose resin,
Examples include a halogen-containing resin, a hydrogen bonding resin, a liquid crystal resin, a polyphenylene oxide resin, a polymethylene oxide resin, a polycarbonate resin, a polysulfone resin, a polyethersulfone resin, and a polyetheretherketone resin.

Preferred examples of the resin include a resin containing a high hydrogen bonding resin having a hydrogen bonding group or an ionic group described below. The content of the hydrogen bonding group or the ionic group in the high hydrogen bonding resin (when both are included, the total amount of both) is usually 20 to 60 mol%, preferably 30 to 50 mol%. is there. The content of these hydrogen bonding groups and ionic groups can be measured, for example, by a nuclear magnetic resonance (NMR) technique (1H-NMR, 13C-NMR, etc.).

The above-mentioned hydrogen bonding group includes a hydroxyl group, an amino group, a thiol group, a carboxyl group, a sulfonic acid group,
Examples of the ionic group include a carboxylate group, a sulfonate ion group, a phosphate ion group, an ammonium group, and a phosphonium group. Among the hydrogen bonding groups or ionic groups, more preferred are a hydroxyl group, an amino group, a carboxyl group, a sulfonic acid group, a carboxylate group, a sulfonic acid ionic group, an ammonium group and the like.

Specific examples of the high hydrogen bonding resin include, for example, polyvinyl alcohol, an ethylene-vinyl alcohol copolymer having a vinyl alcohol content of 40 mol% or more, polysaccharides, polyacrylic acid and its esters, and polyacrylic acid. Sodium acid, polysulfonic acid, sodium polysulfonate, polyethyleneimine, polyallylamine and its quaternary ammonium salt, polyvinyl thiol, polyglycerin and the like. Among the above-mentioned resins, more preferred are polyvinyl alcohol and polysaccharides.

Here, the polyvinyl alcohol is, for example, a polymer obtained by hydrolyzing or transesterifying (saponifying) an acetic ester portion of a vinyl acetate polymer (ie, a copolymer of vinyl alcohol and vinyl acetate). And a polymer obtained by saponifying a vinyl trifluoroacetate polymer, a vinyl formate polymer, a vinyl pivalate polymer, a t-butyl vinyl ether polymer, a trimethylsilyl vinyl ether polymer, etc. (for details of polyvinyl alcohol). Is, for example, edited by the Poval Society, "World of PVA", 1992,
Nagano et al., “Poval” 1981
Year, see Polymer Publishing Association).

"Saponification" in polyvinyl alcohol
Is preferably 70% or more in terms of molar percentage, more preferably 85% or more, and particularly preferably 98% or more, a so-called fully saponified product. The degree of polymerization of polyvinyl alcohol is preferably from 100 to 5,000, more preferably from 200 to 3,000. Furthermore, the PVA referred to in the present invention may be modified with a small amount of a comonomer as long as the object of the present invention is not hindered.

The modified polyvinyl alcohol is as follows:
In the process of producing polyvinyl alcohol, a vinyl ester, particularly a vinyl acetate monomer, is copolymerized with another unsaturated monomer copolymerizable therewith. Examples of the other unsaturated monomers include olefins such as ethylene, propylene, α-hexene and α-octene, (meth) acrylic acid, crotonic acid, maleic acid (anhydride), fumaric acid, and itaconic acid. Sulfonic acid-containing monomers such as vinylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid and the like, and their alkali salts, dimethylaminoethyl (meta) )
Acrylate, diethylaminoethyl (meth) acrylate, trimethyl-2-(-1- (meth) acrylamide-1,1-dimethylethyl) ammonium chloride, trimethyl-3- (1- (meth) acrylamidopropyl) ammonium chloride, -Vinyl-2-ethylimidazole and other quaternizable cationic monomers,
Examples include styrene, alkyl vinyl ether, (meth) acrylamide, and others.

The ratio of these copolymer components is not particularly limited, but is 5 to vinyl alcohol units.
0 mol% or less, preferably 30 mol% or less is preferable, and various forms obtained by any method such as random copolymerization, block copolymerization, and graft copolymerization are used as the form of copolymerization. .

Among these copolymers, a block copolymer obtained by copolymerizing a polycarboxylic acid component with a polyvinyl alcohol component is particularly preferably used, and when the polycarboxylic acid component is polymethacrylic acid, Particularly preferred. Further, the block copolymer is particularly preferably an AB block copolymer in which a polyacrylic acid chain is extended at one end of a polyvinyl alcohol chain, and the polyvinyl alcohol block component (a) Weight ratio of acrylic acid block component (b) (a) /
(B) is preferably 50/50 to 95/5,
In the case of 60/40 to 90/10, particularly preferable gas barrier properties are completed, and the bonding characteristics with the base material layer are remarkably completed. Further, among other modified forms, one particularly preferred form is a silyl group-modified polyvinyl alcohol resin composed of a saponified vinyl ester polymer modified with at least one compound having a silyl group in the molecule. is there.

The method for obtaining the modified polymer having such a composition is not particularly limited, but a silyl group is added to a vinyl alcohol polymer such as polyvinyl alcohol or modified polyvinyl acetate obtained by a conventional method. Reacting a compound having a silyl group into the polymer, or activating the terminal of polyvinyl alcohol or a modified product thereof, and introducing an unsaturated monomer having a silyl group in the molecule to the terminal of the polymer. Various modification methods such as graft copolymerization of the unsaturated monomer to a vinyl alcohol polymer molecular chain, a copolymer comprising a vinyl ester monomer and an unsaturated monomer having a silyl group in the molecule. And saponifying it, or polymerizing a vinyl ester in the presence of a silyl group-containing mercaptan or the like and saponifying it. Introducing silyl groups into Runado end,
Various methods such as are effectively used.

As the modified polyvinyl alcohol-based resin obtained by such various methods, any resin may be used as long as it has a silyl group in the molecule. The silyl group contained in the molecule may be an alkoxyl group or a silyl group. Those having a reactive substituent such as an acyloxyl group and a hydrolyzate of a silanol group or a salt thereof are preferable, and among them, a silanol group is particularly preferable.

Compounds having a silyl group in the molecule used for obtaining these modified polyvinyl alcohol resins include trimethylchlorosilane, dimethylchlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, triethylfluorosilane. Organohalosilanes such as silane, organosilicon esters such as trimethylacetoxysilane and dimethyldiacetoxysilane, organoalkoxysilanes such as trimethylmethoxysilane and dimethyldimethoxysilane,
Examples include organosilanols such as trimethylsilanol and diethylsilanediol, aminoalkylsilanes such as N-amiethyltrimethoxysilane, and organosilicon isocyanates such as trimethylsiliconisocyanate. The degree of modification by these silylating agents can be arbitrarily adjusted depending on the type, amount and reaction conditions of the silylating agent used.

The unsaturated monomer used in the method for saponifying a copolymer of a vinyl ester monomer and an unsaturated monomer having a silyl group in the molecule is vinyltrimethoxysilane. Many vinylsilane-based compounds such as vinylalkoxysilane and vinylmethyldimethoxysilane represented by vinyltriethoxysilane, and alkyl- or allyl-substituted vinylalkoxysilane represented by vinyltriisopropoxysilane; Further, polyalkylene glycol-modified vinyl silanes in which a part or all of these alkoxy groups are substituted with a polyalkylene glycol such as polyethylene glycol can be given. Furthermore, 3- (meth) acrylamino-propyltrimethoxysilane, 3
(Meth) acrylamide-alkylsilane represented by-(meth) acrylamide-propyltriethoxysilane and the like can also be preferably used.

On the other hand, a method for polymerizing a vinyl ester in the presence of a mercaptan having a silyl group and then saponifying the silyl group to introduce a silyl group into the terminal includes an alkoxysilylalkyl such as 3- (trimethoxysilyl) -propylmercaptan. Mercaptan is preferably used.

The suitable range varies depending on the degree of modification of the modified polyvinyl alcohol-based resin of the present invention, that is, the content of the silyl group, the degree of saponification, etc., but it is important for the gas barrier property which is the object of the present invention. It becomes a factor. The content of the silyl group is usually 30 mol% or less, preferably 10 mol% or less, particularly preferably 5 mol% or less, as a monomer containing a silyl group, based on the vinyl alcohol unit in the polymer. Used. Although the lower limit is not particularly limited, the effect is particularly remarkably exhibited when it is 0.1 mol% or more.

The above silylation rate indicates the ratio of the introduced silyl group after the silylation to the amount of the hydroxyl group contained in the polyvinyl alcohol resin before the silylation.

Of course, these various polyvinyl alcohol resins may be used singly. However, as long as the object of the present invention is not impaired, they may be used as copolymers with other copolymerizable monomers or mixed with other monomers. It can be used in combination with other possible resin compounds. Examples of such a resin include polyacrylic acid or esters thereof, polyester resin, polyurethane resin, polyamide resin, epoxy resin, melamine resin, and others.

The polysaccharide is a biopolymer synthesized in a biological system by polycondensation of various monosaccharides, and here includes those chemically modified based on them. Examples include cellulose and cellulose derivatives such as hydroxymethylcellulose, hydroxyethylcellulose and carboxymethylcellulose, amylose, amylopectin, pullulan, curdlan, xanthan, chitin, chitosan and the like.

The ethylene-vinyl alcohol copolymer (hereinafter referred to as EVOH) has a vinyl alcohol content of from 40 mol% to 80 mol%, more preferably from 45 mol% to 75 mol%. It means a certain EVOH. In addition, the melt index of EVOH (temperature 190
The value measured under the conditions of ° C and a load of 2160 g; hereinafter, referred to as MI) is not particularly limited, but is 0.1 to 50 g / 10 minutes. Further, the EVOH referred to in the present invention may be modified with a small amount of a comonomer as long as the object of the present invention is not hindered.

The above-mentioned modified form of EVOH is modified to be crosslinked, preferably modified to be soluble in alcohol. In order to impart such properties, a silyl group is introduced into EVOH.

The introduction of the silyl group can be performed, for example, by using 3-isocyanatopropyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, triethylfluoroorganohalosilane,
It is carried out by reacting a reactive silane compound, such as trimethylacetoxysilane, with a hydroxyl group of EVOH.

The introduction of the silyl group, that is, the silylation, must be carried out so that at least EVOH becomes soluble in alcohol. Specifically, it is preferable that the silylation rate is 0.2 mol% or more. The upper limit of the silylation rate is not particularly limited from the viewpoint of alcohol solubility, but from the viewpoint of the arrangement of the inorganic layered compound in the present invention,
It is preferably at most 5 mol%, more preferably at most 2 mol%. The above silylation rate is the value of EVO before silylation.
It shows the ratio of the introduced silyl groups after silylation to the amount of hydroxyl groups contained in the H resin.

Modified EVOH into which the above silyl group has been introduced
Is dissolved in an alcohol-based solvent due to the presence of the introduced silyl group by heating and dissolving with an alcohol or a mixed solvent of alcohol / water. The modified EVOH dissolved in the solvent, on the other hand, cross-links by a part of the introduced silyl group reacting by a dealcoholization reaction and a dehydration reaction. In the above reaction, the presence of water is essential, and it is preferable to use a mixed solvent of alcohol / water.

The coating liquid is a liquid in which the above-mentioned inorganic layered compound and resin are dispersed or dissolved in a dispersion medium. From the viewpoint of the gas barrier properties of the obtained gas barrier container, the dispersion medium is preferably a liquid that swells or cleaves the above-mentioned inorganic layered compound.

The composition ratio of the inorganic layer compound to the resin in the coating liquid is not particularly limited, but generally, the weight ratio of the inorganic layer compound to the resin (inorganic layer compound / resin) is 1/100 to 100%. 100/1, furthermore 1/20 to 10/1
Is preferably within the range. The higher the weight ratio of the inorganic layered compound is, the more excellent the gas barrier property is, but in consideration of the bending resistance, the range of 1/20 to 2/1 is more preferable.

The concentration of the highly hydrogen-bonding resin and the inorganic layered compound in the above coating solution is generally preferably in the range of 0.1% by weight to 70% by weight, and preferably 1% by weight. More preferably in the range of ~ 15% by weight,
It is more preferable that it is in the range of 4% by weight to 10% by weight from the viewpoint of productivity.

Gas barrier layer 3 (coating solution) in the present invention
In the case where the resin used is a high hydrogen bonding resin, a crosslinking agent for a hydrogen bonding group can be used for the purpose of improving the water resistance of the gas barrier layer 3.

Preferable examples of the crosslinking agent include coupling agents such as titanium coupling agents, silane coupling agents, melamine coupling agents, epoxy coupling agents, isocyanate coupling agents, and the like. Epoxy compounds, copper compounds, zirconium compounds, organometallic compounds and the like can be mentioned. From the viewpoint of improving water resistance, organometallic compounds, zirconium compounds, water-soluble epoxy compounds, silane coupling agents are more preferably used,
More preferably, it is an organic metal compound such as an organic titanium compound.

Specific examples of the zirconium compounds include zirconium halides such as zirconium oxychloride, zirconium hydroxychloride, zirconium tetrachloride and zirconium bromide; and mineral acids such as zirconium sulfate, basic zirconium sulfate and zirconium nitrate. Zirconium salts of organic acids such as zirconium formate, zirconium acetate, zirconium propionate, zirconium caprylate and zirconium stearate;
Examples include zirconium complex salts such as ammonium zirconium carbonate, sodium zirconium sulfate, ammonium zirconium acetate, sodium zirconium oxalate, sodium zirconium citrate, and zirconium ammonium citrate.

Specific examples of the water-soluble epoxy compound include sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, glycidyl ether epoxy resin, heterocyclic epoxy resin, glycidylamine epoxy resin, and aliphatic epoxy resin. I can give it.

Examples of the silane coupling agent include amino silane coupling agents, vinyl or methacryloxy silane coupling agents, epoxy silane coupling agents, methyl silane coupling agents,
Chloro silane coupling agents and mercapto silane coupling agent systems are exemplified.

Preferable examples of the crosslinking agent for a hydrogen-bonding group include a reaction for forming a cross-linked structure by reacting with a plurality of functional groups of a high hydrogen-bonding resin, that is, an organic metal compound capable of a cross-linking reaction. For example, the above-mentioned organometallic compounds which react with a plurality of hydroxyl groups of polyvinyl alcohol and form a cross-linking by a coordination bond or an ionic bond between a metal atom of the organometallic compound and an oxygen atom of the hydroxyl group are preferable.

The above-mentioned organometallic compounds capable of undergoing a crosslinking reaction are:
Higher crosslinking reactivity and higher crosslinking efficiency than inorganic metal salts. However, if the cross-linking reactivity is too high, the cross-linking reaction proceeds in the coating solution and coating (coating) becomes impossible, but the cross-linking reactivity of the organometallic compound can be changed by appropriately changing the ligand. Easy to control. The organic metal compound is also superior to the inorganic metal salt in that it has the advantage that the reactivity is easily controlled. Among the organometallic compounds, an organometallic compound having a chelating ligand such as acetylacetonate has an appropriate crosslinking reactivity and is preferable as a crosslinking agent for a hydrogen bonding group.

Preferred examples of such organometallic compounds include organic titanium compounds, organic zirconium compounds, organic aluminum compounds and organic silicon compounds.

Specific examples of the organic titanium compound include titanium orthoesters such as tetra-n-butyl titanate, tetraisopropyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate and tetramethyl titanate; titanium acetylacetonate;
Titanium chelates such as titanium tetraacetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate, titanium triethanolamine, titanium ethyl acetoacetate, and titanium acylates such as polyhydroxytitanium stearate. No.

Specific examples of the organic zirconium compound include zirconium normal propylate, zirconium normal butyrate, zirconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium bisacetylacetonate, zirconium acetylacetonate bisethylacetoacetate and the like. No.

Specific examples of the organoaluminum compound include aluminum acetylacetonate, aluminum organic acid chelate and the like. Examples of the organic silicon compound include a silicon compound having a ligand included in the compounds exemplified as the organic titanium compound or the organic zirconium compound.

Among these, a chelate compound is preferred in terms of stability in a coating solution. In terms of the stability of the coating solution, the stability is greatly improved by setting the coating solution to be acidic. The above acidic conditions include a pH of 5
Or less, more preferably pH 3 or less. There is no particular lower limit on the pH of the coating solution, but usually the pH is 0.1.
5 or more. As the addition method, it is preferable to dilute with an alcohol and add. By including the step of mixing the resin and the crosslinking agent, the gas barrier layer 3 in which the resin is crosslinked can be obtained.

The amount of the crosslinking agent to be added is not particularly limited, but the ratio K (K = CN / HN) of the number of moles of the crosslinking group (CN) of the crosslinking agent to the number of moles of the hydrogen bonding group (HN) of the resin is used. But,
It is preferable to use it in the range of 0.001 or more and 10 or less. More preferably, the molar ratio K is in the range of 0.01 or more and 1 or less.

The method of blending or producing the resin composition comprising the above-mentioned inorganic layered compound and resin is not particularly limited.
From the viewpoint of uniformity or ease of operation at the time of blending, for example, after mixing a liquid obtained by dissolving a resin in a solvent and a dispersion obtained by previously swelling and cleaving an inorganic layered compound with a dispersion medium,
A method of removing a solvent and a dispersion medium (method 1), a method in which a dispersion liquid in which an inorganic layered compound is swollen and cleaved by a dispersion medium is mixed with a resin, the resin is dissolved in the dispersion medium, and then the dispersion medium is removed. Method (method 2), a method in which an inorganic layered compound is added to a liquid in which a resin is dissolved in a solvent, and the inorganic layered compound is swelled and cleaved using the solvent as a dispersion medium to form a dispersion, and the solvent is removed (method 3). Alternatively, a method of hot-kneading the resin and the inorganic layered compound (method 4) can be used. The former three methods are preferably used from the viewpoint that a large aspect ratio of the inorganic layered compound can be easily obtained. In the former three cases, it is preferable to perform treatment using a high-pressure dispersion device from the viewpoint of dispersibility of the inorganic layered compound.

As a high-pressure dispersion device, for example, Microflu
There is an ultra-high pressure homogenizer (trade name: Microfluidizer) manufactured by idics Corporation or a Nanomizer manufactured by Nanomizer, and a Menton-Gaulin type high-pressure dispersing apparatus such as a homogenizer manufactured by Izumi Food Machinery.

In the above three methods, after removing the solvent and the dispersion medium from the system and laminating, the resulting gas barrier container is subjected to heat aging at, for example, 110 ° C. or more and 220 ° C. or less. Is preferable because it can improve the water resistance (meaning of gas barrier properties after a water resistance environment test).

Although the aging time is not limited, it is necessary that the gas barrier container reaches at least a set temperature. For example, in the case of a method using a heat medium such as a hot air dryer,
It is preferably from 1 second to 100 minutes. There is no particular limitation on the heat source, and various methods such as heat roll contact, heat medium contact (air, oil, etc.), infrared heating, and microwave heating can be applied.

The above aging treatment exhibits a particularly excellent effect in improving the water resistance when the resin is a high hydrogen bonding resin.

The high-pressure dispersion treatment in the present invention is, as shown in FIG. 5, by passing a composition mixture obtained by mixing particles to be dispersed or a dispersion medium, etc., through a plurality of narrow tubes 11 to collide with each other. Dispersing under special conditions such as high shear and high pressure.

In such a high-pressure dispersion treatment, the composition mixture is preferably passed through a thin tube 11 having a diameter of 1 μm to 1000 μm. When the composition mixture passes through the small tube 11, a maximum pressure condition is applied to the composition mixture. It is preferable that a pressure of 100 kgf / cm ² or more is applied.
/ Cm ² or more, more preferably 1000 kgf / cm ²
The above is particularly preferred. In addition, the composition mixture is a thin tube 11
When passing through the inside, the maximum arrival speed of the composition mixture is 1
00 m / s or more, and the heat transfer rate is 1
It is preferably at least 00 kcal / hr.

The principle of the high-pressure treatment in the high-pressure dispersion treatment apparatus used for the high-pressure dispersion treatment will be schematically described.
The composition mixture is sucked into the feeder tube 13 having a larger diameter than the thin tube 11 by the pump 12 and taken in. Subsequently, a high pressure is applied to the composition mixture in the feeder tube 13 by the pump 12. At this time,
Check valve provided on feeder tube 13 (not shown)
As a result, the composition mixture in the feeder tube 13 is
Extruded toward one. Therefore, the composition mixture is in a high-pressure and high-speed state in the thin tube 11,
Each of the inorganic layered compound particles of the composition mixture collides with each other and the inner wall of the thin tube 11, and the diameter and thickness, particularly the thickness, of each of the inorganic layered compound particles are finely divided and more uniformly dispersed. Then, it is taken out of the discharge pipe 14 to the outside.

For example, when the flow velocity at the point where the maximum velocity is instantaneously reached with respect to the composition mixture as the processed sample in the thin tube 11 is 300 m / s, the volume is 1 × 10 5
^-3 m ³ a in cubic passed by ^{1 / (3 × 10 5)} sec, when the temperature of the composition mixture is raised 35 ° C., energy is transferred to the composition mixture by pressure loss. The heat transfer rate is such that the specific gravity of the composition mixture is 1 g / cm ^{3 and the} specific heat 1 ca.
At 1 / g ° C., it is 3.8 × 10 ⁴ kcal / hr.

In the gas barrier container according to the present invention, corona treatment, flame plasma treatment, ozone treatment, electron beam irradiation treatment, and anchor treatment are performed to improve the adhesion between the gas barrier layer 3 and the substrate. You may go during. Although any of these processes is not particularly limited, for example, an anchor process is suitably used.

The anchor treatment is a treatment for forming an anchor layer 2 between a substrate 1 and a gas barrier layer 3 as shown in FIG. The material of the anchor layer 2 is not particularly limited, but preferably contains an isocyanate compound and an active hydrogen compound.

As the isocyanate compound contained in the anchor layer 2, tolylene diisocyanate (TD)
I), 4,4'-diphenylmethane diisocyanate (MD
I), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), 4,4'-methylenebiscyclohexyl isocyanate (H12MDI), isophorone diisocyanate (IPDI) and the like.

The active hydrogen compound may be any compound having a functional group capable of binding to an isocyanate compound. Examples thereof include ethylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol,
1,6-hexanediol, neopentyl glycol, low molecular weight polyols such as trimethylolpropane, polyethylene glycol, polyoxypropylene glycol,
Ethylene oxide / propylene oxide copolymers, polyether polyols such as polytetramethylene ether glycol, poly-β-methyl-δ-valerolactone,
Polycaprolactone, polyester polyols such as polyester from diol / dibasic acid, and the like.

In the active hydrogen compound, a low molecular weight polyol is particularly preferable, and a diol in the low molecular weight polyol is more preferable. Here, diols include ethylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and the like, and dibasic acids such as adipic acid, azelaic acid, sebacic acid, and isophthalic acid And terephthalic acid. Other polyols include active hydrogen compounds such as castor oil, liquid polybutadiene, epoxy resin, polycarbonate diol, acrylic polyol, and neoprene.

The mixing ratio between the isocyanate compound and the active hydrogen compound is not particularly limited, but the amount to be added may be determined in consideration of the equivalence relationship between the isocyanate group and the active hydrogen group, for example, —OH, —NH, and —COOH. preferable. For example, the ratio R (R = A) between the number of moles of isocyanate groups (AN) and the number of moles of active hydrogen groups (BN) of the active hydrogen compound
N / BN) is preferably 0.001 or more from the viewpoint of adhesive strength, and is preferably 10 or less from the viewpoint of tackiness and blocking. The number of moles of the isocyanate group and the active hydrogen group can be determined by 1H-NMR and 13C-NMR.

The method of laminating the anchor layer 2 on the container 1 as a base material is not particularly limited, but a coating method using an anchor coating agent solution obtained by dissolving an anchor coating agent containing an isocyanate compound and an active hydrogen compound in a solvent is used. The method is preferred. Specific examples of the coating method include a direct gravure method, a reverse gravure method, a microgravure method, a roll coating method such as a two roll beat coating method and a bottom feed three reverse coating method, and a doctor knife method and a die coating method. Examples include a dip coating method (dipping method), a bar coating method, and a coating method combining these methods.

The solvent component in the anchor coating agent solution is mainly an organic solvent, and includes alcohols, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, esters, ketones, ethers, and the like. Halogenated hydrocarbons and mixed solvents thereof are exemplified.

The coating thickness of the anchor coating agent solution applied to the container 1 in the form of a film is not particularly limited, but is preferably set so that the dry thickness is 0.01 μm to 5 μm. The larger the coating thickness, the better the heat sealing strength, but the lower the gelboflex resistance. Therefore, the coating thickness is more preferably from 0.03 μm to 2.0 μm.
m, more preferably 0.05 μm to 1.0 μm
It is.

With the anchor layer 2, it is possible to obtain better adhesion than simply stacking the gas barrier layer 3 on the container 1. The gas barrier layer 3 may contain a surfactant in order to further improve the adhesiveness of the resin.

The surfactant is not particularly limited as long as it can improve the adhesiveness between the anchor layer 2 and the gas barrier layer 3. Examples of the surfactant include anionic surfactants, cationic surfactants, and the like. Zwitterionic and non-ionic surfactants are included.

Examples of the anionic surfactant include a carboxylic acid type such as an aliphatic monocarboxylate, N-acyloylglutamate, an alkylbenzene sulfonate, a naphthalene sulfonate-formaldehyde condensate, and a sulfosuccinic dialkyl ester. Hydrocarbon-based anionic interfaces such as sulfonic acid type, alkyl sulfate type, sulfate type such as alkyl sulfate polyoxyethylene salt, phosphate type such as alkyl phosphate salt, borate type such as alkyl borate salt Activators, fluorinated anionic surfactants such as sodium perfluorodecanoate and sodium perfluorooctylsulfonate; silicone-based anionics having anionic groups such as polymers having polydimethylsiloxane groups and metal carboxylate Surfactants.

Examples of the cationic surfactant include an amine salt type such as an alkylamine salt and a quaternary ammonium salt type such as an alkyltrimethylammonium salt, a dialkyldimethylammonium salt and an alkyldimethylbenzylammonium salt.

Examples of the amphoteric surfactant include carboxybetaine type such as betaine N, N-dimethyl-N-alkylaminoacetate and glycine such as 1-alkyl-1-hydroxyethyl-1-carboxymethylimidazolinium betaine. Type.

Examples of the nonionic surfactant include ester types such as glycerin fatty acid ester, sorbitan fatty acid ester and sucrose fatty acid ester, polycondensates of polydimethylsiloxane groups and alkylene oxide adducts, and polysiloxane-polyoxyalkylene copolymers. Polymers, ether type such as polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene block polymer, etc., ester ether type such as polyethylene glycol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, aliphatic alkanolamide Alkanolamide type, such as
Fluorine types such as perfluorodecanoic acid-diglycerin ester and perfluoroalkylalkylene oxide compounds are exemplified.

Among the above surfactants, in particular, those having 6 carbon atoms
An alkali metal salt of a carboxylic acid having an alkyl chain of not more than 24 or less, an ether type nonionic surfactant such as polydimethylsiloxane-polyoxyethylene copolymer (silicone nonionic surfactant), Fluorinated nonionic surfactants such as alkyl ethylene oxide compounds (fluorinated nonionic surfactants)
Is preferred.

In the case where a coating liquid is used when forming the gas barrier layer 3, for example, the amount of the surfactant is preferably 0.001 to 5% by weight in the coating liquid from the viewpoint of the effect. 0.003 to 0.5% by weight is more preferable,
Particularly preferred is 0.5 to 0.1% by weight.

The base resin used for the preformed container 1 is not particularly limited, and examples thereof include kraft paper, woodfree paper, imitation paper, glassine paper, parchment paper, synthetic paper, and various types of balls. Paper such as paper, polyethylene (low density, high density), ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer,
Polypropylene resin such as polypropylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ionomer resin, polyethylene terephthalate, polybutylene terephthalate, polyester resin such as polyethylene naphthalate, nylon-6,
Nylon-6,6, meth-xylenediamine-adipic acid condensation polymer, amide resin such as polymethylmethacrylimide, acrylic resin such as polymethylmethacrylate, polystyrene, styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene copolymer Polymer, styrene such as polyacrylonitrile-acrylonitrile resin, cellulose triacetate, hydrophobic cellulose resin such as cellulose diacetate, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, halogen-containing resin such as Teflon, polyvinyl alcohol, High hydrogen bonding resin such as ethylene-vinyl alcohol copolymer, cellulose derivative, polycarbonate resin, polysulfone resin, polyethersulfone resin, polyetheretherketone resin, poly Eniren'okishido resins, polymethylene oxide resins, engineering plastics resins such as liquid crystal resins.

On the surface of the container 1 on which the anchor layer 2 is laminated,
Further, the method of laminating the gas barrier layer 3 is not particularly limited, but a method of applying a coating liquid of the resin composition to the surface of the container 1, drying and heat-treating, or a method of applying the resin composition film to the anchor layer later. A method of laminating 2 is preferred, and a method of performing the above-mentioned coating is particularly preferred. In addition, at the time of coating, the resin contained in the coating liquid is preferably the high hydrogen bonding resin from the viewpoint of dispersibility.

Examples of the coating method include a roll coating method such as a direct gravure method, a reverse gravure method, a microgravure method, a two roll beat coating method, a bottom feed three reverse coating method, a doctor knife method, a die coating method, and a dip coating method. Methods (dipping method), bar coating methods, and coating methods combining these methods.

The film thickness of the gas barrier layer 3 is 10
μm or less is preferable, and 1 μm or less is more preferable.
Particularly preferred is a range of 1 to 1 μm. In particular, when transparency of the gas barrier container is required, the thickness is preferably 1 μm or less. In order to obtain sufficient gas barrier properties, the thickness of the gas barrier layer 3 should be 1 nm.
It is preferable that it is above.

The gas barrier layer 3 formed by the above-described laminating method can exhibit excellent gas barrier properties, and has excellent impact resistance, irrespective of the shape of the container formed in advance, and has a very excellent gas barrier property. It can be a container. When the thickness of the formed gas barrier layer 3 is within the above range, the transparency of the container is not impaired, and the gas barrier layer 3 as an impurity that hinders recycling is reduced. Can be improved.

Further, in the gas barrier container according to the present invention, as shown in FIG.
A sealant layer 4 for improving heat sealability may be laminated. The resin used for the sealant layer 4 is
Although not particularly limited, polyethylene (low-density, high-density), ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer is used because of problems such as heat seal strength, deodorization of food odor, and resin odor. , Ethylene-4-methyl-1-pentene copolymer, ethylene-octene copolymer, polypropylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene- Polyolefin resins such as acrylic acid copolymers, ionomer resins and ethylene-vinyl alcohol copolymers; polyacrylonitrile resins (PAN); polyester resins; and the like are preferably used.

In the gas barrier container according to the present invention, it is preferable to use the sealant layer 4 having a high impact strength, particularly when the sealing property of the contents is required. Examples of such a resin include polyethylene and ethylene-ethylene obtained using a metallocene catalyst or a late transition metal complex catalyst.
Polyolefin resins such as α-olefin copolymers are preferred. Such a sealant layer 4 has a density of 0.92.
It is preferably 0 g / cm ³ or less.

The method for laminating the sealant layer 4 is as follows.
Although not particularly limited, for example, a method in which the resin used for the sealant layer 4 is dissolved in a solvent and coated on the gas barrier layer 3 made of an inorganic layered compound and a resin, and the sealant layer 4 is extruded and laminated on the gas barrier layer 3 Preferred examples include a method and a method of dry laminating the sealant layer 4 on the gas barrier layer 3. The interface between the sealant layer 4 and the gas barrier layer 3 may be subjected to a corona treatment, an ozone treatment, an electron beam treatment, or a treatment such as an anchor coating agent.

Further, as long as the effects of the present invention are not impaired,
At least one of the container 1, the anchor layer 2, the gas barrier layer 3, and the sealant layer 4 may be mixed with various additives such as an ultraviolet absorber, a crosslinking agent, a coloring agent, and an antioxidant.

The gas barrier container according to the present invention has an oxygen permeability of 1 mL / m ² · day · atm or less, preferably 0.1 mL / m ² · day · atm or less, more preferably 0.05 mL / m ² · day · atm or less. / M ² · day · atm. Therefore, oxygen and the like do not enter the container from the outside air. Therefore, the deterioration of the contents is more effectively suppressed, and the contents can be stored for a long period of time.

The shape of the gas barrier container according to the present invention is not particularly limited as long as the gas barrier container is processed into a shape that does not form a gap or a hole through which outside air can enter. Specific examples of the shape of the gas barrier container include, for example, a tray, a cup, a pair of a vacuum / pressure molded container and a lid, a pair of an injection or press molded container and a lid, a squeeze bottle, a bag-in-box, and a brick. Shaped container, gable top, composite container, lami tube, plastic can container, square bottom bag container, paper carton container, bottle,
A tank and the like can be mentioned. Among the above packaging shapes, a squeeze bottle and a liquid filling tank for storing and packaging a liquid are particularly preferable.

As described above, the gas barrier container according to the present invention is suitably used for packaging and preserving contents that are deteriorated by contact with outside air or contain volatile components such as moisture. It is. Such contents are not particularly limited, but include foods, pharmaceuticals, and electronic materials. Among them, many foods are significantly deteriorated by oxygen, and thus the gas barrier container according to the present invention can be suitably used as a food packaging material.

The shape of the food packaging material is not particularly limited, and the food to be packaged is not particularly limited. However, for example, fresh foods such as prepared foods, processed livestock products, and processed marine products are oxidized by contact with oxygen, or the moisture contained in the fresh foods evaporates or deteriorates remarkably. It is particularly suitable as a packaging application for packaging materials.

In addition, many quasi-drugs, including pharmaceuticals and toiletries, are deteriorated by contact with oxygen or evaporation of volatile components such as moisture. It can also be suitably used as a packaging material for pharmaceuticals.

As described above, the gas barrier container according to the present invention is obtained by laminating a gas barrier layer made of a resin composition having an inorganic layered compound on the inner surface of a previously formed container. Therefore, excellent gas barrier properties can be provided regardless of the shape of the container,
It is possible to increase the degree of freedom as a container, for example, by molding a container in advance according to the shape of the contents and then laminating a gas barrier layer later.

Further, since the food packaging material according to the present invention is provided with the gas barrier container, deterioration of the contents can be more effectively suppressed as compared with the conventional food packaging material. Long-term storage can be made possible. Therefore, it is not limited only to foods, but can be used for any packaging in such a form.

[0132]

The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, in this Example and a comparative example, various physical properties of the gas barrier container (food packaging material) were measured as follows.

[Thickness Measurement] The thickness of 0.5 μm or more was measured with a commercially available digital thickness gauge (contact type thickness gauge, trade name: ultra-high precision decimicro head MH-15M, manufactured by Nippon Kogaku Co., Ltd.). On the other hand, a thickness of less than 0.5 μm is determined by a gravimetric method (the measured weight of a container having a certain area is divided by the area,
Furthermore, a calibration curve of the actual coating film thickness and IR absorption was prepared by the IR method or by the IR method, and determined by the calibration curve. Further, in the case of measuring the thickness of the coating film of the resin composition of the present invention, the elemental analysis method (from the specific inorganic element analysis value (derived from the barrier layer) of the container and the specific element fraction of the inorganic layered compound alone) is used. According to the method of the present invention for determining the ratio between the barrier layer and the container.

[Measurement of Particle Size] Using a laser diffraction / scattering particle size distribution analyzer (LA910, manufactured by HORIBA, Ltd.), a volume-based median of particles considered to be an inorganic layered compound present in the resin matrix of the medium. The diameter was measured as a particle diameter L. The undiluted dispersion was measured at a light wavelength of 50 μm in a paste cell, and the diluent of the dispersion was measured at a light wavelength of 4 mm by a flow cell method.

[Aspect Ratio Calculation] X-ray diffractometer (XD
-5A (manufactured by Shimadzu Corporation), the diffraction measurement of the inorganic layered compound alone and the resin composition by the powder method was performed. Thereby, the unit thickness a of the inorganic layered compound was obtained, and further, from the diffraction measurement of the resin composition, it was confirmed that there was a portion where the interplanar spacing d of the inorganic layered compound was widened. Using the particle diameter L obtained by the above-described method, the aspect ratio Z is calculated as follows: Z = L / a
It calculated by the formula of.

[Oxygen Permeability Measurement] Based on JIS K7126, an oxygen permeability measuring device (OX-TRANML: M
OCON) at 23 ° C. and 50% RH.

[Example] Dispersing pot [Product name: Despa MH-
L, manufactured by Asada Tekko Co., Ltd.], 1410 g of ion-exchanged water (specific electric conductivity 0.7 μS / cm or less) was added, and polyvinyl alcohol [PVA117H; manufactured by Kuraray Co., Ltd.
Saponification degree: 99.6%, polymerization degree: 1700] and 50 g under low-speed stirring (1500 rpm, peripheral speed: 4.10 m / min).
Heat to 5 ° C., stir for 1 hour, and dissolve.

Next, the temperature was lowered to 60 ° C. while stirring, and 15 g of 1-butanol was added dropwise to adjust the final 1-butanol fraction to 1% by weight. Then, 25 g of natural montmorillonite (Kunipia F; manufactured by Kunimine Industry Co., Ltd.) was added as powder, and after confirming that montmorillonite was substantially precipitated in the liquid, high-speed stirring (31)
(00 rpm, peripheral speed: 8.47 m / min) for 90 minutes to obtain a resin composition mixed solution (A) having a total solid content concentration of 5 wt%. (The particle size of the cleaved natural montmorillonite (Kunipia F) is 560 nm, the a value obtained from powder X-ray diffraction is 1.2156 nm, and the aspect ratio (Z) is 200 or more.) Further, 1-butanol 9
A liquid obtained by adding 0.18 g of a nonionic surfactant SH3746 (polyoxyethylene-methylpolysiloxane copolymer, manufactured by Dow Corning Toray Co., Ltd.) to a mixed liquid of 2 g and 277 g of isopropyl alcohol was designated as (B). I do.

The liquid (B) was added to the liquid (A) under low-speed stirring (15
00 rpm, peripheral speed 4.10 m / min), and further added titanium acetylacetonate [TC1
00, manufactured by Matsumoto Pharmaceutical Co., Ltd.] under low-speed stirring (1500
(3.3 rpm) at a peripheral speed of 4.10 m / min).

An inner surface of a 700 μm-thick blow-molded polyethylene terephthalate (PET) bottle was coated with an anchor coat agent [Adcoat AD335 / CAT10 = 1.
5/1 (weight ratio): manufactured by Toyo Morton Co., Ltd.] by a dipping method. The dry thickness of the anchor coat layer was 0.15 μm.

Further, as TOP coating liquid, coating liquid 1
Was coated by a dipping method to obtain a PET bottle as a gas barrier container having a gas barrier layer based on the coating liquid 1 formed on the anchor coat layer. The dry thickness of the gas barrier layer was 0.5 μm. This P
When the oxygen permeability of the ET bottle was measured according to the above-described measurement method, it was 0.1 mL / m ² · day · atm or less, which was excellent in barrier properties.

[Comparative Example] Ordinary P without coating solution 1
When the oxygen permeability of the ET bottle (the same one used in the above example) was measured, it was inferior in the barrier property.

As described above, the gas barrier container and the food packaging material according to the present invention show excellent gas barrier properties and can significantly suppress the deterioration of the contents, as is apparent from the results of the oxygen permeability described above. .

[0144]

As described above, the gas barrier container according to the first aspect of the present invention has a structure in which a gas barrier layer made of a resin composition having an inorganic layered compound is laminated on the inner surface of a preformed container. Configuration.

As described above, the gas barrier container according to claim 2 of the present invention has the following features:
The gas barrier layer has a configuration in which the gas barrier layer is laminated by coating a coating liquid comprising a resin composition having an inorganic layered compound.

As described above, the gas barrier container according to the third aspect of the present invention has the structure described in the first or second aspect, and further includes a blow molding method, a vacuum molding method, a pressure molding method, and an injection molding method. This is a configuration made of a resin molded by any one of a molding method and a press molding method.

As described above, the gas barrier container according to claim 4 of the present invention has the following features.
The container is configured to be a squeeze bottle.

As described above, the gas barrier container according to claim 5 of the present invention has the following features.
The container is configured to be a liquid filling tank.

As described above, the gas barrier container according to the sixth aspect of the present invention has an oxygen permeability of 1 mL / m ² · da in addition to the configuration according to any one of the first to fifth aspects.
y ・ Atm or less.

As described above, the gas barrier container according to the seventh aspect of the present invention has a structure in which the inorganic layered compound swells in a dispersion medium in addition to the configuration according to any one of the first to sixth aspects. It is a configuration that cleaves.

As described above, the gas barrier container according to claim 8 of the present invention has a structure in which, in addition to the structure according to any one of claims 1 to 6, the gas barrier layer comprises a resin having an inorganic layered compound. This is a configuration obtained by subjecting a mixed solution of the composition to a high-pressure dispersion treatment.

According to the ninth aspect of the present invention, as described above, in addition to the configuration of the eighth aspect,
The high pressure dispersion treatment is performed under a pressure condition of 100 kgf / cm ² or more.

As described above, the gas barrier container according to the tenth aspect of the present invention, in addition to the configuration according to any one of the first to eleventh aspects, has an aspect ratio of the inorganic layered compound of 50 to 5000. Is within the range.

As described above, the gas barrier container according to the eleventh aspect of the present invention has an aspect ratio of the inorganic layered compound of 200 to 3000 in addition to the configuration according to any one of the first to twelfth aspects. The configuration is within the range.

The gas barrier container according to the twelfth aspect of the present invention is, as described above, in addition to the configuration according to any one of the first to thirteenth aspects, wherein the resin composition comprises a high hydrogen bonding resin. And the weight ratio of the inorganic layered compound to the high hydrogen bonding resin is in the range of (1/100) to (100/1).

[0156] As described above, the gas barrier container according to claim 13 of the present invention, in addition to the configuration according to claim 12, is characterized in that the high hydrogen bonding resin comprises a hydrogen bonding group or an ionic group per unit weight of resin. Mol% is 30% or more, 50%
The configuration is as follows.

As described above, in the gas barrier container according to claim 14 of the present invention, in addition to the structure described in claim 12 or 13, the highly hydrogen-bonding resin is polyvinyl alcohol and a modified product thereof, or a polysaccharide. Or an ethylene-vinyl alcohol copolymer and a modified product thereof.

Therefore, in the above configuration, a gas barrier layer made of a resin composition having an inorganic layered compound is formed on a pre-molded container, so that the container has a different shape than usual. Even if there is, the effect that excellent gas barrier properties can be provided is exerted. Further, since this gas barrier layer has an inorganic layered compound as described above, it also has an effect that it can exhibit excellent impact resistance even compared to various layers formed conventionally. Play.

The food packaging material according to the fifteenth aspect of the present invention is, as described above, any one of the first to fourteenth aspects.
It is a configuration provided with the gas barrier container described in the section.

Therefore, with the above configuration, it is possible to provide a food packaging material capable of preserving the contents for a long period of time, and to form the gas barrier layer later. Various containers are formed in advance in accordance with the shape and type, so that there is an effect that a food packaging material having a high degree of freedom such that a gas barrier layer is appropriately formed can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing the structure of a gas barrier layer according to one embodiment of the present invention.

FIG. 2 is an X-ray diffraction graph of the inorganic layered compound for calculating the “unit thickness a” of the inorganic layered compound in the gas barrier container.

FIG. 3 is an X-ray diffraction graph of an inorganic layered compound for calculating “plane spacing d” of the inorganic layered compound in the gas barrier container.

FIG. 4 calculates the “plane spacing d” of the inorganic layered compound when the peak corresponding to the “plane spacing d” overlaps the halo (or background) and is difficult to detect in the graph of FIG. It is an X-ray diffraction graph at the time.

FIG. 5 is an explanatory view schematically showing a high-pressure dispersion process used in manufacturing the gas barrier container.

FIG. 6 is a schematic sectional view showing an example of a sectional structure of the gas barrier container according to the present invention.

FIG. 7 is a schematic sectional view showing another example of the sectional structure of the gas barrier container of the present invention.

[Explanation of symbols]

 Reference Signs List 1 container 2 anchor layer 3 gas barrier layer 4 sealant layer

Claims (15)

[Claims] 1. A gas barrier container wherein a gas barrier layer made of a resin composition having an inorganic layered compound is laminated on an inner surface of a preformed container. 2. The gas barrier container according to claim 1, wherein said gas barrier layer is laminated by coating a coating liquid comprising a resin composition having an inorganic layered compound. 3. The method according to claim 1, wherein the container is a blow molding method, a vacuum molding method,
The gas barrier container according to claim 1, wherein the gas barrier container is made of a resin molded by any one of a pressure molding method, an injection molding method, and a press molding method. 4. The gas barrier container according to claim 3, wherein said container is a squeeze bottle. 5. The gas barrier container according to claim 3, wherein said container is a liquid filling tank. 6. The gas barrier container according to claim 1, wherein the oxygen permeability is 1 mL / m ² · day · atm or less. 7. The method according to claim 1, wherein said inorganic layered compound swells and cleaves in a dispersion medium.
Item 7. The gas barrier container according to item 1. 8. The gas barrier layer according to claim 1, wherein the gas barrier layer is obtained by subjecting a mixed solution of a resin composition having an inorganic layered compound to high-pressure dispersion.
Item 7. The gas barrier container according to item 1. 9. The method according to claim 1, wherein the high-pressure dispersion treatment is performed at 100 kgf / cm ^2.
9. The gas barrier container according to claim 8, wherein the treatment is performed under the above pressure conditions. 10. An inorganic layered compound having an aspect ratio of 50.
The gas barrier container according to any one of claims 1 to 9, wherein the gas barrier container is in a range from 5,000 to 5,000. 11. An inorganic layered compound having an aspect ratio of 200.
The gas barrier container according to any one of claims 1 to 10, wherein the gas barrier container is in a range of -3000. 12. The above resin composition contains a high hydrogen bonding resin, and the weight ratio of the inorganic layered compound to the high hydrogen bonding resin is in the range of (1/100) to (100/1). The gas barrier container according to any one of claims 1 to 11, characterized in that: 13. The gas barrier container according to claim 12, wherein the high hydrogen bonding resin has a molar percentage of hydrogen bonding groups or ionic groups per unit weight of the resin of 30% or more and 50% or less. 14. The gas barrier according to claim 12, wherein the high hydrogen bonding resin is polyvinyl alcohol and a modified product thereof, or a polysaccharide, or an ethylene-vinyl alcohol copolymer and a modified product thereof. container. 15. A food packaging material comprising the gas barrier container according to any one of claims 1 to 14.