JPH07251475A - Laminated film - Google Patents

Abstract

PURPOSE:To provide a gas barrier film having high-level gas barrier properties. CONSTITUTION:A laminated film is obtained by laminating at least one layer composed of a resin compsn. containing an inorg. laminar compd. with a particle size of 5mum or less and an aspect ratio of 50-5000 on the membrane layer 2 of metal or metal oxide formed on at least one surface of a resin film 3.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminated film having excellent gas barrier properties.

[0002]

BACKGROUND OF THE INVENTION Although various functions are required for packaging, various gas barrier properties for protecting contents are important properties that affect the storability of foods. Distribution forms, diversification of packaging technology, regulation of additives However, due to changes in tastes and the like, the need for it is increasing. The gas barrier property was also a weak point of general plastic materials. Degradation factors of food include oxygen, light, heat, water, etc., and oxygen is particularly important as a substance causing it. The barrier material is a material that is indispensable for effectively blocking oxygen and at the same time controlling the deterioration of foods such as gas filling and vacuum packaging.In addition to oxygen gas, various gases, organic solvent vapors, fragrances, etc. By having a barrier function,
It can be used for rust prevention, deodorization, and sublimation prevention, and is used in many fields such as confectionery bags, skipjack packs, retort pouches, carbon dioxide beverage containers, and other food products, cosmetics, agricultural chemicals, medical care, and the like.

Among the films made of thermoplastic resin, particularly oriented films of polypropylene, polyester, polyamide and the like have excellent mechanical properties, heat resistance and transparency and are widely used as packaging materials. There is. However, when these films are used for food packaging, they have insufficient oxygen and other gas barrier properties,
Various problems such as oxidative deterioration and alteration of contents due to aerobic microbes, permeation of aroma components, loss of flavor, and moistening of contents by external moisture, resulting in poor mouthfeel. Tend to occur. Therefore, a method such as stacking another film layer having a good gas barrier property is usually adopted.

As a method of exhibiting gas barrier properties, there is a method of dispersing a flat inorganic material in a resin. For example, in JP-A-62-148532, a concentration of 1,6-hexanepolycarbonate diol of 30 is used. % Polyurethane resin solution 100 parts by weight Mica fine powder 25 parts by weight, dimethylformamide 60 parts by weight A coating liquid composition is coated on a releasable substrate, dried, and then peeled off from the substrate. The method is described. Also, Japanese Patent Laid-Open No. 64-043554
In the publication, an aqueous solution of ethylene / vinyl alcohol copolymer in methanol has an average length of 7 μm and an aspect ratio of 14 μm.
A method of adding 0 mica, pouring it into cold water for precipitation, filtering, drying, pelletizing and then obtaining a film is described. Further, JP-A-3-93542
Japanese Patent Application Laid-Open Publication No. 2004-242242 discloses a coating composition in which modified silyl group-containing modified polyvinyl alcohol and synthetic hectorite are in a weight ratio of 50:50.
T), and heat treatment (130-150).
C.) is described. However, the films obtained by these techniques have gas barrier properties
It's not enough, and it's not always satisfactory.

Conventionally, as one of important means for imparting gas barrier properties, at least one of films made of a thermoplastic resin, metal such as aluminum or silica,
A method is known in which an oxide such as alumina is formed into a thin film by a method such as vacuum deposition to provide a barrier property. However, there is a problem that the performance of the film is greatly reduced due to the deformation of the film due to the fact that pinholes are easily generated in the process of forming the thin film and the flexibility and mechanical strength of the thin film are insufficient. It is not always satisfactory.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a gas barrier molded article or film having a high level of gas barrier property.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that a film obtained by laminating a layer composed of an inorganic layered compound and a resin on a metal or oxide thin film is remarkably excellent. The inventors have found that a gas barrier property is exhibited and have completed the present invention.

According to the present invention, an inorganic layered compound having a particle size of 5 μm or less and an aspect ratio of 50 or more and 5000 or less and a resin are provided on a metal or oxide thin film layer formed on at least one surface of a resin film. And a layered film formed by laminating at least one layer made of a resin composition. .

The inorganic layered compound used in the present invention is
An inorganic compound in which unit crystal layers are stacked on each other to have a layered structure. In other words, "layered compound" means
A compound or substance having a layered structure, and a "layered structure" is a structure in which atoms are strongly bonded by covalent bonds or the like and the densely arranged faces are stacked in parallel by weak bonding forces such as van der Waals forces. Say. The “inorganic layered compound” that can be used in the present invention has an aspect ratio of 50 or more and 5000 or less and a particle size of 5 μm as measured by the method described below.
The following are not particularly limited. From the viewpoint of gas barrier properties, the aspect ratio is preferably 100 or more (particularly 200 or more). When the aspect ratio is less than 50, the gas barrier property is insufficiently expressed. On the other hand, it is technically difficult to obtain an inorganic layered compound having an aspect ratio of more than 5,000, and it is expensive in terms of cost or economy. From the viewpoint of ease of manufacturing, the aspect ratio is preferably 2000 or less (further 1500 or less). From the viewpoint of the balance between gas barrier properties and easiness of production, the aspect ratio is more preferably in the range of 200 to 3000. From the viewpoint of film formability or moldability when formed into a film, the “particle size” measured by the method described below is preferably 5 μm or less. If the particle size exceeds 5 μm, the film-forming property or moldability of the resin composition tends to deteriorate. From the viewpoint of transparency of the resin composition, the particle size is preferably 3 μm or less. When the film of the present invention is used for applications where transparency is important (for example, food applications), it is particularly preferable that the particle size is 1 μm or less. Also, this transparency is
The total light transmittance at a wavelength of 500 nm is preferably about 80% or more (more preferably 85% or more). Such transparency can be suitably measured with, for example, a commercially available spectrophotometer (manufactured by Hitachi, Ltd., self-recording spectrophotometer Model 330). Specific examples of the inorganic layered compound include graphite, phosphate-based derivative-type compounds (zirconium phosphate-based compounds), chalcogenides [Group IV (Ti, Zr,
Hf), group V (V, Nb, Ta) and group VI (Mo,
W) is a dichalcogenide and is represented by the formula MX ₂ . Here, X represents chalcogen (S, Se, Te). ], Clay-based minerals and the like can be mentioned.

Since it is extremely difficult to measure the true particle size in a resin composition, the particle size of the inorganic layered compound used in the present invention is a value determined by a dynamic light scattering method in a solvent.
When sufficiently swelling with a solvent of the same kind as the solvent used in the dynamic light scattering method to form a composite with the resin, the particle size of the inorganic layered compound in the resin can be considered to be close to the particle size in the solvent.

The aspect ratio (Z) of the inorganic layered compound used in the present invention is represented by the relationship Z = L / a.
[L is a particle size obtained by a dynamic light scattering method in a solvent, and a is a unit thickness of the inorganic layered compound (unit thickness a is a measurement of the inorganic layered compound alone by a powder X-ray diffraction method or the like. It is a value determined by.)]. However, Z = L / a
, The interplanar spacing d obtained from powder X-ray diffraction of the composition
Exists and satisfies the relationship of a <d. Here, it is necessary that the value of da is larger than the width of the resin single chain in the composition. Z cannot necessarily be said to be the true aspect ratio of the inorganic layered compound in the resin composition, but for the following reasons,
It is quite valid.

Direct measurement of the aspect ratio of the inorganic layered compound in the resin composition is extremely difficult. Composition powder X
Between the interplanar spacing d obtained by the line diffraction method and the unit thickness a determined by the powder X-ray diffraction measurement of the inorganic layered compound alone, a <d
If the value of da is equal to or more than the width of the resin single chain in the composition, it means that the resin is inserted between the layers of the inorganic layered compound in the resin composition. It is clear that the thickness of the layered compound is the unit thickness a. In addition, it is extremely difficult to measure the true particle size in the resin composition, but in the case of swelling sufficiently with a solvent of the same kind as the solvent used in the dynamic light scattering method to form a composite with the resin, It can be considered that the particle size of the inorganic layered compound in is very close to that in the solvent (however, the particle size L determined by the dynamic light scattering method is the major axis Lma of the inorganic layered compound).
Since it is considered that x does not exceed x, the true aspect ratio Lmax / a cannot theoretically fall below the definition Z of the aspect ratio in the present invention. ). From the above two points, the definition of the aspect ratio of the present invention is considered to be relatively valid. In the present invention, the aspect ratio or particle size means the aspect ratio and particle size defined above. For details of how to obtain a and d, refer to, for example, Shu Iwao et al., Encyclopedia of Clay, pages 35 and below and pages 271 and below, 1985, Asakura Shoten Co., Ltd. 5-11).
The width of the resin single chain in the composition can be determined by simulation calculation or the like (for example, Okamura et al., Introduction to Polymer Chemistry, pages 103 to 110, 1981).
Years, Kagaku Dojin), 4-5 angstroms for polyvinyl alcohol (2-3 angstroms for water molecules). Thus, the diffraction peak (corresponding to the surface spacing d) observed in the powder X-ray diffraction of the resin composition
The integrated intensity of is a relative ratio of the reference diffraction peak (corresponding to the surface spacing a) to the integrated intensity of 2 or more (further 10
Or more) is preferable. FIG. 5 is a graph schematically showing the relationship between the X-ray diffraction peak of the inorganic layered compound and the unit thickness a of the compound. FIG. 6 is a graph schematically showing the relationship between the X-ray diffraction peak of the resin composition containing the inorganic layered compound and the plane spacing d of the composition. FIG. 7 shows the relationship between the X-ray diffraction peak of the resin composition and the interplanar spacing d of the composition when the peak corresponding to the interplanar spacing d overlaps with the halo (or background) and is difficult to detect. It is a graph which shows typically. In this figure, 2
The area excluding the base line on the lower angle side than θd is defined as the peak corresponding to the surface spacing d (θd is the diffraction angle corresponding to “unit thickness a + width of single resin chain”). FIG. 8 shows polyvinyl alcohol PVA117H /
3 is a graph showing an X-ray diffraction peak of a Kunipia F composition and a graph showing an X-ray diffraction peak of Kunipia F (montmorillonite). FIG. 9 is a graph showing an X-ray diffraction peak (pattern of FIG. 6) of the composition having the interplanar spacing d = 19.62 angstrom. In FIG. 10, the surface spacing d = 32.
X-ray diffraction peak of the 94 Å composition (Fig. 6).
And the pattern of FIG. 7). FIG. 11 shows
8 is a graph showing X-ray diffraction peaks (pattern of FIG. 7) of a composition having a surface spacing d of 44.13 Å or more.

As the inorganic layered compound having a large aspect ratio, an inorganic layered compound which swells and cleaves in a solvent is preferably used. The degree of "swelling / cleavage" of the inorganic layered compound used in the present invention in a solvent is as follows.
It can be evaluated by the "cleavage" test. The swelling property of the inorganic layered compound is preferably about 5 or more (more preferably about 20 or more) in the following swelling test.
On the other hand, the cleavage property of the inorganic layered compound is preferably about 5 or more (more preferably about 20 or more) in the following cleavage property test. In these cases, a solvent having a density lower than that of the inorganic layered compound is used as the solvent. When the inorganic layered compound is a natural swelling clay mineral, it is preferable to use water as the solvent. <Swelling test>: Inorganic layered compound 2 g, solvent 100 mL
Slowly add to the container (contain a 100 mL graduated cylinder). After shaking and standing, the volume of the former (inorganic layered compound dispersed layer) is read from the scale of the interface between the inorganic layered compound dispersed layer and the supernatant after 24 hours at 23 ° C. The larger this value, the higher the swelling property. <Cleavability test>: 30 g of the inorganic layered compound is used as the solvent 150
Add slowly to 0 mL, disperser (manufactured by Asada Tekko KK, Despar MH-L, blade diameter 52 mm, rotation speed 3100 rp)
m, container volume 3 L, bottom-blade distance 28 mm), and dispersed at a peripheral speed of 8.5 m / sec for 90 minutes (23
℃), take 100 mL of the dispersion liquid, put it in a 100 mL graduated cylinder and let stand for 60 minutes, then read the volume of the inorganic layered compound dispersion layer from the scale of the interface with the supernatant. The larger this value, the higher the cleavability. As the inorganic layered compound that swells and cleaves in a solvent, a clay mineral that has a swelling and cleaving property in a solvent can be preferably used. Clay-based minerals are generally
A type having a two-layer structure having an octahedron layer having a central metal such as aluminum or magnesium on a tetrahedral layer of silica, and a tetrahedral layer of silica having an octahedron layer having a central metal such as aluminum or magnesium. It is classified as a type consisting of a three-layer structure in which is sandwiched from both sides. Examples of the former include kaolinites and antigorites, and examples of the latter include smectites, vermiculites and mica depending on the number of interlayer cations. Specifically, kaolinite, dickite,
Nacrite, halloysite, antigorite, chrysotile, pyrophyllite, montmorillonite, hectorite, tetrasilylic mica, sodium teniolite, muscovite, margarite, talc, vermiculite, phlogopite, xanthophyllite, chlorite, etc. be able to.

The solvent for swelling the present inorganic layered compound is not particularly limited. For example, in the case of a natural swelling clay mineral, water, alcohols such as methanol, dimethylformamide, dimethylsulfoxide, acetone and the like can be mentioned. Alcohols such as methanol are more preferred.

The resin used in the present invention is not particularly limited, but for example, polyvinyl alcohol (PV
A), ethylene-vinyl alcohol copolymer (EVO
H), polyvinylidene chloride (PVDC), polyacrylonitrile (PAN), polysaccharides, polyacrylic acid and its esters, and the like.

As a preferred example, the weight percentage of hydrogen bonding groups or ionic groups per unit weight of resin is 20% to.
A high hydrogen-bonding resin satisfying the ratio of 60% can be mentioned. A more preferable example is one in which the weight percentage of hydrogen-bonding groups or ionic groups per unit weight of the resin of the high hydrogen-bonding resin satisfies the ratio of 30% to 50%. Examples of the hydrogen-bonding group of the high-hydrogen-bonding resin include a hydroxyl group, an amino group, a thiol group, a carboxyl group, a sulfonic acid group, and a phosphoric acid group, and examples of the ionic group include a carboxylate group, a sulfonate ion group, and a phosphoric acid group. Ionic groups, ammonium groups, phosphonium groups and the like can be mentioned. Among the hydrogen-bonding groups or ionic groups of the high hydrogen-bonding resin, more preferable examples include a hydroxyl group, amino group, carboxyl group, sulfonic acid group, carboxylate group, sulfonate ion group, ammonium group, and the like. To be

Specific examples include, for example, polyvinyl alcohol, ethylene-vinyl alcohol copolymer having a vinyl alcohol fraction of 41 mol% or more, hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, amylose, amylopectin, pullulan, curdlan, xanthan. Polysaccharides such as chitin, chitosan, cellulose, pullulan, chitosan, etc., polyacrylic acid, sodium polyacrylate, polybenzenesulfonic acid, sodium polybenzenesulfonate, polyethyleneimine, polyallylamine, its ammonium salt polyvinylthiol, poly Glycerin, etc. are mentioned.

Further preferred examples of the high hydrogen bond resin include polyvinyl alcohol and polysaccharides.
The polyvinyl alcohol used in the layer containing the inorganic layered compound of the present invention is a polymer having a monomer unit of vinyl alcohol as a main component. Examples of such "polyvinyl alcohol" include, for example, a polymer obtained by hydrolyzing or transesterifying (saponifying) the acetic ester portion of a vinyl acetate polymer (precisely, it is a copolymer of vinyl alcohol and vinyl acetate). And a polymer obtained by saponifying a trifluorovinyl acetate polymer, a vinyl formate polymer, a vinyl pivalate polymer, a t-butyl vinyl ether polymer, a trimethylsilyl vinyl ether polymer (“polyvinyl alcohol”).
For more details, refer to, for example, "The World of PVA", edited by Poval Society, 1992, Polymer Publishing Co., Ltd .; Nagano et al., Poval, 1981, Polymer Publishing Co., Ltd.) . The degree of "saponification" in polyvinyl alcohol is preferably 70% or more in terms of molar percentage, and 85
% Or more, more preferably 98% or more, a so-called completely saponified product. The degree of polymerization is 100.
Or more and 5000 or less (more preferably 200 or more and 3
000 or less is preferable).

The term "polysaccharide" as used herein means a biopolymer synthesized in a biological system by polycondensation of various monosaccharides, and here, those chemically modified based on them are also included. For example, cellulose and cellulose derivatives such as hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, amylose, amylopectin, pullulan, curdlan, xanthan, chitin,
Examples include chitosan.

When the resin used in the present invention is a high hydrogen-bonding resin, a hydrogen-bonding group cross-linking agent may be used for the purpose of improving its water resistance (meaning barrier property after water resistance environment test). it can.

The crosslinking agent for hydrogen-bonding group is not particularly limited, but examples thereof include titanium coupling agents, silane coupling agents, melamine coupling agents, epoxy coupling agents, isocyanate coupling agents,
A copper compound, a zirconia compound, etc. are mentioned, More preferably, a zirconia compound is mentioned.

Specific examples of zirconia compounds include zirconium oxychloride, zirconium hydroxychloride, zirconium tetrachloride, zirconium halides such as zirconium bromide, zirconium sulfate, basic zirconium sulfate, zirconium nitrate and other mineral acids. Zirconium salts of organic acids such as salts, zirconium formate, zirconium acetate, zirconium propionate, zirconium caprylate, zirconium stearate, ammonium zirconium carbonate, sodium zirconium sulfate, ammonium zirconium acetate, sodium zirconium oxalate, sodium zirconium citrate, citric acid Zirconium complex salts such as zirconium ammonium,
And so on.

The amount of the cross-linking agent for hydrogen-bonding groups added is the ratio (K) of the number of moles of cross-linking groups (CN) of the cross-linking agent to the number of moles of hydrogen-bonding groups (HN) of the high hydrogen-bonding resin (K) [. That is, K = C
N / HN] is not particularly limited as long as it is in the range of 0.001 or more and 10 or less, but is preferably in the range of 0.01 or more and 1 or less.

The composition ratio (volume ratio) of the inorganic layered compound and the resin used in the present invention is not particularly limited,
Generally, the volume ratio of (inorganic layered compound / resin) is 5/95.
To 90/10, and more preferably the volume ratio is 5/95 to 50/50. Also, 5/95 to 30/70
In the range of 7, the flexibility of the film is improved, and 7/93 to 17/8
In the range of 3, there are advantages that the deterioration of the barrier property due to bending is small and the peel strength is strong. Also,
When the volume fraction of the inorganic layered compound is smaller than 5/95,
The barrier performance is not sufficient, and if it exceeds 90/10, the film-forming property is not good.

The method of blending the composition comprising the inorganic layered compound and the resin is not particularly limited. For example, a solution in which the resin is dissolved and a dispersion in which the inorganic layered compound has been swollen and cleaved in advance are mixed, and then the solvent is used. The method of removing the swelling, the dispersion of swelling and cleaving the inorganic layered compound is added to the resin, the method of removing the solvent, the swelling of the inorganic layered compound is added to the solution of the resin.
After cleavage, a method of removing the solvent, a method of thermally kneading the resin and the inorganic layered compound, and the like can be mentioned. The former three methods are preferably used as a method for easily obtaining a particularly large aspect ratio.

In the former three methods, the solvent is removed from the system and then heat-aged at 110 ° C. or higher and 220 ° C. or lower to improve the water resistance of the film (meaning the barrier property after the water resistance environment test). To do. Although the aging time is not limited, it is necessary that the film reaches at least the set temperature, and in the case of a method using a heating medium contact such as a hot air dryer, it is preferably 1 second or more and 100 minutes or less. The heat source is also not particularly limited, and includes heat roll contact, heat medium contact (air, oil, etc.), infrared heating, microwave heating,
Various other types can be applied. In addition, the water resistance effect here is remarkably high when the resin is a high hydrogen-bonding resin, and when the inorganic layered compound is a clay mineral having a swelling property.

The metal or oxide thin film used in the present invention is not particularly limited as a metal, but one that is stable in air is preferable, and aluminum whose film surface is oxidatively stabilized after forming the thin film is preferably used. . As the oxide, aluminum oxide, silicon oxide, titanium oxide, zinc oxide and the like are preferable, and the oxidation state thereof may be various.

The film thickness of the metal or oxide thin film used in the present invention is preferably 1 nm or more and 1000 nm or less. It is more preferably 10 nm or more and 300 nm or less.

The method of forming the metal or oxide thin film used in the present invention is not particularly limited, and a CVD method, a sputtering method, a sol-gel method or the like can be used in addition to the general vacuum deposition method. The metal is not particularly limited, but one that is stable in air is preferable, and aluminum whose film surface is stabilized by oxidation after forming a thin film is preferably used. As the oxide, aluminum oxide, silicon oxide, titanium oxide, zinc oxide and the like are preferable, and the oxidation state thereof may be various.

The resin film for forming the metal or oxide thin film used in the present invention is not particularly limited, but biaxially oriented polyethylene terephthalate, biaxially oriented nylon, biaxially oriented polypropylene and the like are preferably used.

The method for laminating the layer containing the inorganic layered compound on the thin film layer of metal or oxide is not particularly limited. A coating method in which a coating liquid of the composition is applied to the surface of a substrate on a thin film layer of metal or oxide, followed by drying and heat treatment, a method of laminating a layer containing an inorganic layered compound later, and the like are preferable. Further, the interface between the both may be treated with corona treatment or anchor coating agent. As a coating method, a direct gravure method, a reverse gravure method, a micro gravure method, a roll coating method such as a two roll beat coating method, a bottom feed three reverse coating method, a doctor knife method, a die coating method, a dip coating method, and a bar coating method. Examples thereof include a coating method and a coating method combining these methods.

The coating thickness of the layer containing the inorganic layered compound is not particularly limited, but the dry thickness is preferably 10 μm or less, more preferably 1 μm or less (1 μm or less also has the advantage that the transparency of the laminate is extremely high). It is also preferable for applications that require transparency because it has a matching property. The lower limit is not particularly limited, but is preferably 1 nm or more in order to obtain an effective gas barrier effect.

The base material of the laminated film is not particularly limited, and general base materials such as resin, paper, aluminum foil, wood, cloth and non-woven fabric can be mentioned. As the resin used as the base material, polyethylene (low density, high density), ethylene-
Propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, polypropylene, ethylene-vinyl acetate copolymer,
Polyethylene resin such as ethylene-methyl methacrylate copolymer, ionomer resin and other polyolefin resin, polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, nylon-
6, nylon-6,6, methaxylenediamine-adipic acid condensation polymer, amide resin such as polymethylmethacrylimide, acrylic resin such as polymethylmethacrylate, polystyrene, styrene-acrylonitrile copolymer, styrene-acrylonitrile -Butadiene copolymer, 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, ethylene-vinyl alcohol copolymer, hydrogen-bonding resins such as cellulose derivatives, polycarbonate resins, polysulfone resins, polyethersulfone resins, polyetheretherketone resins, Polyphenylene oxide resins, polymethylene oxide resins, engineering plastics resins such as liquid crystal resin.

Among these, in the laminate in the film form, the outer layer is biaxially stretched polypropylene,
Polyethylene terephthalate, nylon or K-coated polyvinylidene chloride-coated biaxially stretched polypropylene, polyethylene terephthalate, nylon, etc. are preferably arranged, and the inner layer generally has a good heat-sealing property. , For example, polyethylene (low density, high density), ethylene-
Propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, polypropylene, ethylene-vinyl acetate copolymer,
Ethylene-methyl methacrylate copolymer, ionomer resin and the like are preferably used.

Further, in the present invention, various additives such as an ultraviolet absorber, a colorant, an antioxidant and the like may be mixed as long as the effect is not impaired. The present invention includes a laminated film and a laminate having at least one laminated film layer described above.

[0036]

According to the present invention, the particle size of the inorganic layered compound consisting of the resin and the inorganic layered compound is 5 μm or less on the metal or oxide thin film layer formed on at least one surface of the resin film, Aspect ratio of 50 to 500
By stacking layers of 0 or less, it becomes possible to obtain a gas barrier laminated film having a high level of gas barrier property which has never been obtained.

That is, the film of the present invention is used as a packaging material for foods, such as miso, pickles, side dishes, baby foods, boiled konjac, chikuwa, kamaboko, seafood products, meatballs, hamburgers, genghis khan, ham,
Sausage, other processed meat products, green tea, coffee, black tea, bonito flakes, grated kelp, potato chips, butter peanuts and other oil confectionery, rice crackers, biscuits, cookies, cakes, steamed buns, castella, cheese, butter, mochi, soup, sauce Widely used for foods, ramen, etc., as well as pet foods, agricultural chemicals / fertilizers, infusion packs, etc., as well as semiconductor packaging, oxidizing chemical packaging, precision material packaging, and other medical, electronic, chemical, mechanical, and other industrial materials. It is used for a wide range of applications such as packaging.

[0038]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto.

The methods for measuring various physical properties are described below. [Oxygen permeability] Oxygen permeability measuring device (OX-TRAN 1
0 / 50A, manufactured by MOCON), temperature 31 ° C (humidity control thermostat 2
1 ° C. (relative humidity showed about 61%). [Thickness measurement] A thickness of 0.5 μm or more was measured by a digital thickness meter. When the thickness is less than 0.5 μm, a weight analysis method (the weight measurement value of a film having a certain area is divided by the area and further divided by the specific gravity of the composition), or in the case of a laminate of the composition of the present invention and a substrate, , Elemental analysis method (a method for obtaining the ratio of the resin composition layer of the present invention to the base material from the ratio of the specific inorganic element analysis value (derived from the composition layer) of the laminate and the specific element fraction of the inorganic layered compound alone) It was [Measurement of Particle Size] Ultrafine particle size analyzer (BI-90, manufactured by Brookhaven Co., Ltd.) was used under the conditions of a temperature of 25 ° C. and a water solvent. The central diameter determined by the photon correlation method by the dynamic light scattering method was defined as the particle diameter L. [Aspect ratio calculation] X-ray diffractometer (XD-5A,
Diffraction measurement was performed on the inorganic layered compound alone and the resin composition by a powder method using Shimadzu Corporation. Thus, the interplanar spacing (unit thickness) a of the inorganic layered compound was determined, and it was further confirmed from the diffraction measurement of the resin composition that the interplanar spacing of the inorganic layered compound was wide. Using the particle size L obtained by the above method, the aspect ratio Z is Z = L /
It was determined by the formula a.

[Example 1] Natural montmorillonite (Kunipia F; manufactured by Kunimine Industries Co., Ltd.) was deionized water (0.7 μS /
cm or less) so as to be 2 wt%, and this is used as an inorganic layered compound dispersion liquid (liquid A). The particle size of the natural montmorillonite is 560 nm, the a value obtained from powder X-ray diffraction is 1.2156 nm, and the aspect ratio Z is 46.
It is 1. In addition, polyvinyl alcohol (PVA117
H; manufactured by Kuraray Co., Ltd., saponification degree: 99.6%, polymerization degree: 1700) is dissolved in ion-exchanged water (0.7 μS / cm or less) to a concentration of 2 wt% to obtain a resin solution (solution B). Liquid A and B
The liquid and the solid component ratio (volume ratio) were mixed so that the inorganic layered compound / resin was 3/7, and this was used as a coating liquid. 12 μm thick silicon oxide vapor deposition film (MO
S; gravure coating (test coater; Yasui Seiki Co., Ltd .: micro gravure coating method, coating speed 3 m / min, drying temperature 80 ° C. (heater on the inlet side) 100 degreeC (heater on the outlet side) was performed to obtain a laminated film. The dry thickness of the coating layer was 0.3 μm. The oxygen permeability of this laminated film at 30 ° C. and 60% RH was 0.1 cc / m 2 / day or less. (Table 1) [Examples 2 to 6] Table 1 shows the substrate, the inorganic layered compound, the resin, the ratio of the inorganic layered compound and the resin, the crosslinking agent for the hydrogen-bonding group, and the heat treatment conditions after the film formation. Example 1 with different configurations
A laminated film was prepared by the method described above and an oxygen permeability test was conducted. The results are excellent in gas barrier properties as shown in Table 1. [Example 7] Zirconium ammonium carbonate (Zircosol AC manufactured by Daiichi Rare Element Industry Co., Ltd.)
7 (aqueous solution containing 15 wt% in terms of zirconium oxide) was added to the mixed solution of solution A and solution B so that the ratio of 1 mol of zirconium element to 15 mol of hydroxyl group of polyvinyl alcohol was obtained. An oxygen permeability test was conducted in the same manner as in Example 1 except that the other configurations were as shown in Table 1. The results were excellent in gas barrier properties as shown in Table 1. [Example 8] Zirconium ammonium carbonate (Zircosol AC7 manufactured by Daiichi Rare Elements Industry Co., Ltd. (15 wt% zirconium oxide-containing aqueous solution)) was used as a cross-linking agent for hydrogen-bonding groups based on 15 mol of hydroxyl groups of polyvinyl alcohol. The mixture was added to the liquid mixture of liquid A and liquid B in a molar ratio. Other than the constitutions shown in Table 1, the film was formed in the same manner as in Example 1 and then the film was formed at 140 ° C.
Heat treatment was performed for 0 minutes. As a result of the oxygen permeability test, the first
As shown in the table, the gas barrier property was excellent. [Example 9] An unstretched polypropylene film (Toyobo: Pyrene film CT) was prepared by using a urethane adhesive (Sanyo Kasei: Eunoflex J3) in the layered inorganic compound-containing layer of the laminated film obtained in Example 1. A thickness of 60 μm) was dry-laminated to obtain a laminated film. 30 of this laminated film
Oxygen permeability at 60 ℃ and 60% RH is 0.1cc / m 2 / day
It was below, and was excellent in heat sealability and transparency. Comparative Example 1 Without using the inorganic layered compound dispersion liquid (liquid A),
Polyvinyl alcohol (PVA117H; manufactured by Kuraray Co., Ltd., saponification degree: 99.6%, polymerization degree: 1700) was dissolved in a concentration of 2 wt%, and a resin solution (solution B) was prepared in the same manner as in Example 1. Then, a film was obtained and an oxygen permeability test was conducted. The results were inferior in gas barrier properties as shown in Table 1. [Comparative Examples 2 to 4] Oxygen permeability tests of the metal and oxide vapor deposition films shown in Table 1 were conducted. The results were inferior in gas barrier properties as shown in Table 1. [Comparative Example 5] A film was produced in the same manner as in Example 1 except that the resin solution (B solution) was not used. However, the synthetic mica powder was peeled from the laminated film, and scratches were conspicuous on the film surface, resulting in good lamination. No film was obtained.

[0041]

[Table 1] Abbreviation MOS: Silicon oxide vapor-deposited polyethylene terephthalate film (Oike Kogyo: product name MOS) VMPET: Aluminum oxide vapor-deposited polyethylene terephthalate film (Toyo Aluminum: product name VMPET) AL: Aluminum vapor-deposited polyethylene terephthalate film (Oike industrial product: Tetrait) F: Natural montmorillonite (Kunimine Industries: product name Kunipia F) H: Polyvinyl alcohol (Kuraray: Poval 117
H, degree of polymerization 1700, degree of saponification 99.6 mol%) Z: ammonium zirconium carbonate aqueous solution (manufactured by Daiichi Rare Element Industry: Zircosol AC7) A: heat treatment of laminated film (after drying) at 140 ° C. for 10 minutes

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a layer structure of a cross section of a laminated film of the present invention.

FIG. 2 is a conceptual diagram of the layer structure of the cross section of the laminated film of the present invention.

FIG. 3 is a conceptual diagram of the layer structure of the cross section of the laminated film of the present invention.

FIG. 4 is a conceptual diagram of a layer structure of a cross section of the laminated film of the present invention.

FIG. 5 is a graph schematically showing the relationship between the X-ray diffraction peak of an inorganic layered compound and the unit thickness a of the compound.

FIG. 6 is a graph schematically showing the relationship between the X-ray diffraction peak of a resin composition containing an inorganic layered compound and the interplanar spacing d of the composition.

FIG. 7 is an X-ray diffraction peak of the resin composition when the peak corresponding to the interplanar spacing d overlaps with the halo (or background) and is difficult to detect, and the interplanar spacing of the composition. It is a graph which shows the relationship with d typically.

FIG. 8 shows polyvinyl alcohol PVA117.
It is a graph which shows the X-ray diffraction peak of H / Kunipia F composition, and the graph which shows the X-ray diffraction peak of Kunipia F (montmorillonite).

FIG. 9 is a graph showing an X-ray diffraction peak (pattern of FIG. 6) of a composition having an interplanar spacing d = 19.62 angstroms.

FIG. 10 is a graph showing X-ray diffraction peaks (patterns in FIGS. 6 and 7) of a composition having an interplanar spacing d = 32.94 angstroms.

FIG. 11 is a graph showing an X-ray diffraction peak (pattern of FIG. 7) of a composition having an interplanar spacing d of 44.13 Å or more.

[Explanation of symbols]

 1 Layer Containing Inorganic Layered Compound 2 Metal or Oxide Thin Film Layer 3 Resin Film 4 Base Material for Lamination

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08K 7/00 KCJ C08L 29/04 LGM (72) Inventor Toshiya Kuroda 2-10 Tsukahara, Takatsuki, Osaka No. 1 Sumitomo Chemical Co., Ltd.

Claims (12)

[Claims] 1. An inorganic layered compound having a particle size of 5 μm or less and an aspect ratio of 50 or more and 5000 or less and a resin on a metal or oxide thin film layer formed on at least one surface of a resin film. A laminated film formed by laminating at least one layer made of the resin composition described above. 2. The laminated film according to claim 1, wherein the inorganic layered compound swells and cleaves in a solvent. 3. The laminated film according to claim 2, wherein the inorganic layered compound is a swelling clay mineral. 4. The aspect ratio of the inorganic layered compound is 200.
It is-3000, The laminated film of Claim 1, 2 or 3 characterized by the above-mentioned. 5. The volume ratio of (inorganic layered compound / resin) is (5
/ 95) to (90/10). 5. The laminated film according to claim 1, wherein the laminated film is in the range of / 95) to (90/10). 6. The laminated film according to claim 1, wherein the resin is a high hydrogen-bonding resin. 7. The laminated film according to claim 6, wherein the high hydrogen-bonding resin has a weight percentage of hydrogen-bonding groups or ionic groups per unit weight of resin of 30% or more and 50% or less. . 8. The laminated film according to claim 6, wherein the high hydrogen-bonding resin is polyvinyl alcohol or polysaccharide. 9. The laminated film according to claim 6, wherein the layer containing the inorganic layered compound contains a crosslinking agent for a hydrogen-bonding group. 10. The laminated film according to claim 9, wherein the crosslinking agent for hydrogen-bonding groups is a zirconia compound. 11. A laminate having at least one layer of the laminated film according to any one of claims 1 to 10. 12. The laminate according to claim 1, which has an oxygen permeability of 0.2 cc / m ² · day · atm or less at 30 ° C. and 60% RH. Film or laminate.