JP3780741B2 - Plastic film laminate - Google Patents

Description

【００７３】
参考例１、２および実施例１に対して比較例１及び２は、主成分が水溶性樹脂で密着層が形成されたため、ガスバリア性被膜層形成時に密着層が再溶解して塗布ムラなどの外観不良が発生し、酸素透過率の上昇や密着不良が見られる。また、実施例２〜４に対して比較例３及び４は、密着層などに界面活性剤が添加されていないため、ガスバリア性被膜層の形成状態が悪くピンホールが発生して酸素透過率の上昇が見られる。また、参考例１に対して比較例５では、ガスバリア性被膜層中にモンモリロナイトが含まれていないため、ポリビニルアルコール特有の湿度依存性による酸素透過率の上昇が見られ、さらに、参考例３では金属アルコキシドの添加により酸素透過率を維持したまま耐水性が向上している。以上の実施例のものは、ガスバリア性被膜層状態が良好であり、高度な酸素透過率と高い密着性からガスバリア性包装材料として十分実用性のあるレベルであると言える。
【００７４】
【発明の効果】
以上述べた如く本発明によれば、無機層状化合物と水溶性高分子のガスバリア性被膜層をプラスチックフィルムよりなる基材に塗布するにあたり、密着層としてポリウレタン系樹脂を主たる構成成分とすること、また密着層にカチオン系界面活性剤を配合して形成することで、包装材料として実用性のあるガスバリア性の高いプラスチックフィルム積層体の作成が可能である。
【図面の簡単な説明】
【図１】本発明のプラスチックフィルム積層体の断面図である。
【符号の説明】
１‥‥基材
２‥‥密着層
３‥‥ガスバリア性被膜層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plastic film laminate for packaging used in the packaging field of foods, pharmaceuticals, electronic materials, etc., and the like, and has a particularly high gas barrier property, so that the contents can be obtained from atmospheric oxygen and water vapor. It is related with the plastic film laminated body which interrupts | blocks and suppresses deterioration and a quality change.
[0002]
[Prior art]
In recent years, packaging materials used for packaging foods and non-foods are oxygen, water vapor, and other gases that alter the contents of the packaging material in order to suppress the alteration of the contents and retain their functions and properties. It is necessary to prevent the influence of the above, and it is required to have a gas barrier property that blocks these gases.
[0003]
Therefore, as a conventional gas barrier layer, a metal foil made of a metal such as aluminum or a vapor deposition film thereof, a resin film such as polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinylidene chloride, polyacrylonitrile, or these resins are coated. Plastic films, ceramic deposited films on which inorganic oxides such as silicon oxide and aluminum oxide are deposited have been mainly used.
[0004]
[Problems to be solved by the invention]
However, metal foil and metal vapor-deposited film have excellent gas barrier properties, but the contents cannot be confirmed through the packaging material, metal detectors cannot be used for inspection, and they must be treated as non-combustible materials when discarded after use. There are problems such as unavoidable. Gas barrier resin films and films coated with them are highly temperature and humidity dependent and cannot maintain high gas barrier properties. Furthermore, vinylidene chloride, polyacrylonitrile, etc. may generate harmful substances when discarded or incinerated. There are problems such as. In addition, the ceramic vapor-deposited film or the like has a problem that the vapor-deposited layer lacks flexibility because of ceramic, so that sufficient attention must be paid to processing suitability, and the cost is high because the processing machine is expensive.
[0005]
As a technique for solving such a problem, there is a gas barrier resin film in which a gas barrier coating whose main component is a water-soluble polymer such as polyvinyl alcohol and whose temperature and humidity dependency is suppressed is laminated on a substrate such as a plastic film. In this case, it can be manufactured at low cost by laminating a gas barrier coating layer imparted with a film forming property and adhesion to a plastic material by a wet coating method.
[0006]
The present invention is intended to solve the above-mentioned problems of the prior art, has excellent gas barrier properties with suppressed temperature and humidity dependency, the contents can be seen through, and a metal detector can be used. Another object of the present invention is to provide a gas barrier plastic film laminate having excellent film forming properties and adhesiveness using a wide range of plastic materials as a base material.
[0007]
[Means for Solving the Problems]
  In order to achieve the above object, according to the present invention, first, in claim 1, at least one surface of a base material made of a plastic material has an adhesion layer comprising a polyurethane resin as a main constituent, an inorganic layered compound, and a water-soluble polymer. Gas barrier coating layers with the main constituents ofSecretArrivalIn layersIs a plastic film laminate having a gas barrier property, characterized in that it contains a cationic surfactant.
[0010]
  And claims2In the above, the gas barrier coating layer contains a hydrolyzate of metal alkoxide.1It is set as the plastic film laminated body of description.
[0011]
  And claims3In claim 2, the metal constituting the metal alkoxide is Si, Al or Ti.1 or 2It is set as the plastic film laminated body of description.
[0012]
  And claims4In claim 1, the water-soluble polymer is a polyvinyl alcohol type or a derivative thereof.3The plastic film laminate according to any one of the above.
[0013]
  And claims5In the above, the interlayer distance of the inorganic layered compound in the gas barrier coating layer is increased to 1.2 times or more than the interlayer distance of the inorganic layered compound alone before forming the gas barrier coating layer with the water-soluble polymer. Claims 1 to 3, characterized in that4The plastic film laminate according to any one of the above.
[0014]
  And claims6And wherein the inorganic layered compound is montmorillonite.5The plastic film laminate according to any one of the above.
[0015]
[Action]
  According to the present invention, an adhesion layer and a gas barrier coating layer are sequentially laminated on a plastic substrate.The cationic layer contains a cationic surfactantIn the configuration, since a composite film of a water-soluble polymer and an inorganic layered compound is used as the gas barrier coating layer, it has a high gas barrier property with suppressed temperature and humidity dependency. Furthermore, since both the adhesion layer and the gas barrier coating layer can be applied in-line by wet coating, an existing gravure printing machine can be utilized, continuous production is possible, and low-cost processing is possible.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view illustrating a plastic film laminate of the present invention.
[0017]
The plastic film laminate of the present invention shown in FIG. 1 will be described. A base material 1 in the figure is a film made of a plastic material, on which an adhesive layer 2 mainly comprising a polyurethane-based resin, and further a gas barrier of a composite film mainly comprising an inorganic layered compound and a water-soluble polymer. The conductive film layer 3 is sequentially laminated.
[0018]
  Furthermore, in the present invention, in order to form the gas barrier coating layer 3 in a preferable state.DenseLayering2In order to include a surfactant and form a gas barrier composite material as a coating on a wide range of substrates, a surfactant is added to the adhesion layer 2 containing polyurethane resin as a main constituent.The
[0019]
The base material 1 mentioned above consists of a plastic material, Preferably it is transparent. For example, polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin films such as polyethylene and polypropylene, polystyrene films, polyamide films such as 6-nylon, polycarbonate films, polyacrylonitrile films, polyimide films, etc. A film or the like is used, which may be stretched or unstretched, and preferably has mechanical strength and dimensional stability. These are processed into a film and used.
Of these, a film arbitrarily stretched in the biaxial direction is preferably used, and when it is used as a packaging material, the price, printing suitability, filling suitability, texture, disposability, physical strength, etc. are taken into consideration. Biaxially stretched polypropylene film, polyester film, and polyamide film are more preferable.
[0020]
Various known additives and stabilizers such as antistatic agents, plasticizers, lubricants, antioxidants, and the like may be used on the surface of the substrate 1 to improve adhesion to various films. Therefore, corona discharge treatment, low temperature plasma treatment, ozone treatment, flame treatment, etc. may be performed as pretreatment, and chemical treatment and solvent treatment may be further performed.
[0021]
The thickness of the substrate 1 is not particularly limited, but considers suitability as a packaging material, that other layers may be laminated, and workability when the adhesion layer 2 and the gas barrier coating layer 3 are formed. Then, it is more preferable to set it as 6-30 micrometers depending on a use in the range of 3-200 micrometers practically.
[0022]
  The adhesion layer 2 of the present invention is provided on at least one surface of a base material 1 made of a plastic material, and the film-forming property of the gas barrier coating layer 3 made of a composite of the base material 1, a water-soluble polymer and an inorganic layered compound It is provided for the purpose of improving the adhesion between the layers. In order to achieve the above object, the adhesion layer 2 is a polyurethane resin.DenseLayering2 、 WideIn order to adapt to a range of plastic material base materials, a surfactant is mixed and added to the polyurethane resin constituting the adhesion layer 2Use. BaseWhen using plastic material with surfactant added to material 1GroupIn the case of using a commercially available film as the film used for the material 1, a polypropylene film or the like often contains a surfactant in advance for the purpose of improving the wettability of the coating solution, and the like. In many cases, the surfactant is not contained because the wettability is not improved so much even if a surfactant is added. However, when the base material 1 contains a surfactant, the film forming property of the gas barrier coating layer 3 and the adhesion between the layers are not always obtained, and a surfactant is mixed in the adhesion layer 2. In view of the fact that the method is generally more economical, a surfactant is mixed and added to the polyurethane resin as described above.The
[0023]
The polyurethane-based resin is not particularly limited as long as it has a urethane bond in the main chain or side chain. For example, a polyester polyol or polyether having a urethane bond in the main chain or side chain is of course used. Polyurethane such as polyol and acrylic polyol may be reacted with an isocyanate compound having an isocyanate group to form a urethane bond. Of these, polyurethane resins obtained by mixing polyester polyols such as condensed polyester polyols and lactone polyester polyols and isocyanate compounds such as tolylene diisocyanate, hexamethylene diisocyanate, and xylene diisocyanate are preferred because they have the best adhesion.
[0024]
About a mixing method of both, a well-known method can be used and it does not specifically limit. Also, the blending ratio is not particularly limited, but if there are too few isocyanate compounds, curing failure may be caused. Therefore, the polyol-derived OH groups and the isocyanate compound-derived NCO groups are preferably 1: 0. 5 to 1:40.
[0025]
The surfactant is a general term for an organic composition having a lipophilic group and a hydrophilic group, and since it has an effect of connecting the opposite properties of hydrophilicity and lipophilicity, a detergent raw material, an emulsifier, a dispersion It is used for agents, antistatic agents, lubricants, pigment dispersants, various catalysts and the like.
Surfactant types are classified into anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants depending on the difference in hydrophilic group. By adding these to the polyurethane-based resin constituting the adhesion layer, the surface of the adhesion layer is modified to be hydrophilic, and an effect is exhibited in forming a gas barrier coating layer. In view of economy, cationic surfactants such as amines and pyridine derivatives that can obtain a sufficient effect with a small addition amount are more preferable.
[0026]
The reason why the cationic surfactant exhibits a sufficient function even in a small amount is because the surface of the silicic acid tetrahedral layer on the side where the surface area of the inorganic layered compound which is a constituent component of the gas barrier coating layer is large is charged with a negative charge, The cationic surface active agent is formed in a state in which the inorganic layered compound in the gas barrier coating layer is aligned in parallel to the interface of the adhesion layer by charging the coating surface of the adhesion layer with a positive charge (cation). it is conceivable that.
[0027]
Regarding the addition amount of the surfactant, the mixing ratio of the polyurethane resin / surfactant is preferably in the range of 10,000 / 1 to 10/1 by weight ratio. If it is less than 10000/1, the effect on the formation of the film will not be seen, and if it is more than 10/1, it reacts with the isocyanate compound in the liquid before coating to form a precipitate or the like, and the surfactant is relatively expensive. Therefore, it is not economical.
[0028]
The thickness of the adhesion layer 2 is not particularly limited. However, if the thickness is 0.001 μm or less, the adhesion effect and the film forming effect by the surfactant are weakened. In general, it is preferably in the range of 0.001 to 1 μm, and practically 0.05 to 0.5 μm. The drying method is not particularly limited, and a normal method or the like may be used.
[0029]
Next, the gas barrier coating layer 3 of the present invention will be described. The purpose of this layer is to impart a high level of gas barrier properties and suppress temperature dependence and humidity degradation.
In order to achieve the above object, the gas barrier coating layer is a composite coating comprising an inorganic layered compound and a water-soluble polymer as main components, and more preferably, the interlayer distance of the inorganic layered compound is a composite with a water-soluble polymer. That is, it is 1.2 times or more, more preferably 2 times or more the interlayer distance of the inorganic layered compound alone before the film formation.
[0030]
This interlayer distance can be calculated by determining the bottom reflection (001 plane) of the inorganic layered compound in the gas barrier coating layer by the X-ray diffraction method. That is, according to the calculation based on the X-ray diffraction method, the interlayer distance of the inorganic layered compound before mixing with the water-soluble polymer varies depending on the type of the inorganic layered compound and the type of the water-soluble polymer. It will be 15cm. On the other hand, the interlayer distance of the inorganic layered compound in the gas barrier coating layer in the present invention is 1.2 times or more, more preferably twice or more in order to have gas barrier properties.
[0031]
In the present invention, the inorganic layered compound and the water-soluble polymer are not simply mixed and dispersed in the gas barrier coating layer, but the water-soluble polymer penetrates between the layers of the inorganic layered compound so that it expands. An inorganic layered compound and a water-soluble polymer are complexed at the molecular level. For this reason, it is considered that the gas barrier coating layer has high gas barrier properties and can suppress humidity deterioration and temperature dependency.
[0032]
The gas barrier coating layer will be described in more detail. The inorganic layered compound in the gas barrier coating layer refers to a crystalline inorganic compound having a layered structure, such as kaolinite, halloysite, chlorite, smectite, vermiculite, pyrophyllite, mica and the like. Natural clay minerals and synthetic products such as synthetic smectite. As long as it is an inorganic layered compound, its type, particle size, aspect ratio, and the like can be appropriately selected depending on the desired required quality and the like, and are not particularly limited, but are highly swellable and have a layered structure. Inorganic layered compounds of the smectite group are suitable because a gas-barrier coating layer in which the water-soluble polymer enters between the layers and the layers are enlarged can be easily obtained. Specific examples of the smectite group include montmorillonite and saponite. Among them, montmorillonite is more preferable from the viewpoints of swelling, dispersibility, price and workability.
[0033]
On the other hand, the water-soluble polymer, which is another main component of the gas barrier coating layer, is not particularly limited as long as it is compatible with the inorganic layered compound and easily enters the layer. Polyvinyl alcohols such as alcohol and ethylene-vinyl alcohol copolymer or derivatives thereof, sugars such as cellulose and starch, polymers and derivatives such as polyacrylic acid and methacrylic acid, and the like can be used. Further, judging from the gas barrier property, polyvinyl alcohols or derivatives thereof are more preferable.
[0034]
The above polyvinyl alcohol system is a general term for polymers having hydroxyl groups by polymerization and saponification (alkali treatment) of vinyl acetate, and the degree of saponification is not particularly limited. From 10% remaining partially saponified polyvinyl alcohol to fully saponified polyvinyl alcohol having only a few percent of acetic acid groups remaining, ethylene-vinyl alcohol copolymer polymerized by further containing about 1 to 40 mol% ethylene Can be used widely.
[0035]
About the mixing method of an inorganic layered compound and a water-soluble polymer, a general method can be employ | adopted and it does not specifically limit. Moreover, although the value of a compounding ratio changes with required quality, it is preferable that it is normally the range of 1: 99-90: 10 by the weight ratio of an inorganic layered compound and a water-soluble polymer.
[0036]
In the formation of the gas barrier coating layer, the adjustment of the interlayer distance of the inorganic layered compound in the gas barrier coating layer is carried out by appropriately adjusting the combination of the inorganic layered compound and water-soluble polymer used, the blending ratio, the heating temperature during mixing, etc. This can be done by selecting.
[0037]
In addition, other components can be added to the gas barrier coating layer for various purposes. For example, a hydrolyzate of a metal alkoxide or the like is added for the purpose of further improving the gas barrier property of temperature and humidity dependency, film strength, and water resistance.
[0038]
The metal alkoxide can be represented by the general formula M (OR) n (M is a metal element such as Si, Al, Ti, and R is a lower alkyl group having 1 to 4 carbon atoms). In the invention, for example, tetraethoxysilane or triisopropoxyaluminum can be used. Moreover, as these hydrolysates, both those in which a part of the alkoxide group is hydrolyzed and those that are all hydrolyzed can be used.
[0039]
When obtaining a gas barrier coating layer containing the metal alkoxide hydrolyzate, the metal alkoxide hydrolyzate is added to the composite liquid obtained by mixing the inorganic layered compound and the water-soluble polymer. Just do it. In this case, the addition amount is preferably 1 to 80% by weight with respect to the composite liquid from the viewpoint of water resistance and flexibility.
[0040]
The thickness of the gas barrier coating layer 3 is generally preferably coated so that the thickness after drying is in the range of 0.01 to 50 μm, more preferably in the range of 0.1 to 5 μm. The When the thickness is 0.01 μm or less, it is difficult to obtain a uniform coating film. On the other hand, when the thickness exceeds 50 μm, the film is liable to break and is uneconomical.
[0041]
As a method for forming the adhesion layer 2 and the gas barrier coating layer 3, a normal coating method can be used. For example, dipping method, roll coating, gravure coating, reverse coating, air knife coating, comma coating, die coating, screen printing method, spray coating, gravure offset method and the like can be used. It applies to at least one side of substrate 1 using these coating methods. In this case, the adhesion layer 2 and the gas barrier coating layer 3 may be provided separately, or both layers may be provided simultaneously using a multicolor gravure printing machine or the like. It is more preferable to consider the cost aspect and to form them simultaneously. The drying method is not particularly limited, such as hot air drying, hot roll drying, and infrared irradiation.
[0042]
Further, other layers can be laminated on the gas barrier coating layer 3. For example, a printing layer or a heat seal layer. The printing layer is formed for practical use as a packaging bag or the like, and has been conventionally used as an ink binder resin such as urethane, acrylic, nitrocellulose, polyamide, and vinyl chloride. Characters, pictures, and the like are formed in layers composed of inks to which additives such as various pigments, vehicles, plasticizers, drying agents, stabilizers, and the like are added. As a forming method, for example, a general printing method such as an offset printing method, a gravure printing method, a silk screen printing method, or the like can be used. The thickness is about 0.1 to 2.0 μm.
[0043]
Moreover, when using a multi-color printing machine when laminating | stacking a printing layer, after providing the contact | adherence layer 2 and the gas-barrier film layer 3 previously, a printing layer is laminated | stacked by the printing unit of the same printing machine.
[0044]
The heat seal layer is used as an adhesive part when forming a bag-like package, for example, polyethylene, polypropylene, ethylene-polyvinyl alcohol copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid. Resins such as acid ester copolymers, ethylene-acrylic acid copolymers, ethylene-acrylic acid ester copolymers, and metal cross-linked products thereof are used. As thickness, the range of 15-200 micrometers is generally employ | adopted.
[0045]
As a method for forming the heat seal layer, the film-like material made of the resin is bonded using a one-component wet curing or two-component reaction-curing urethane adhesive, or a non-solvent adhesive. A non-solvent dry laminating method, an extrusion laminating method in which a thermoplastic resin such as polyethylene is melted by heating and extruded into a curtain shape can be formed by a general laminating method.
[0046]
【Example】
The plastic film laminate having gas barrier properties of the present invention will be described in more detail with reference to specific examples.
[0047]
<Adjustment of adhesion layer coating solution>
1) Tolylene diisocyanate (TDI) as an isocyanate compound is added to the main component polyester polyol (molecular weight of about 20000) so that the NCO group derived from the isocyanate compound is 1: 8 in terms of equivalent to the OH group derived from the polyester polyol. The coating liquid 1 which consists of a polyurethane resin component mixed with this was obtained.
[0048]
2) A nonionic surfactant (manufactured by Nippon Oil & Fats Co., Ltd., trade name: Nonion NS220) is added to the coating liquid 1 as an additive at a ratio of 1 to the polyurethane resin component 50 in a solid content weight ratio. A coating solution 2 for an adhesion layer mixed with a surfactant was obtained.
[0049]
3) A cationic surfactant (manufactured by Nippon Oil & Fats Co., Ltd., trade name: cation AB) is added to the coating liquid 1 as an additive at a ratio of 1 to the urethane resin component 200 in a solid content weight ratio, and the interface is added. A coating solution 3 for the adhesion layer mixed with the activator was obtained.
[0050]
4) Polyethyleneimine (manufactured by Toyo Ink Manufacturing Co., Ltd., trade name: AD372) was diluted with a water / methanol = 1/4 solution to obtain a coating solution 4.
[0051]
5) A butadiene-based emulsion (manufactured by Toyo Ink Manufacturing Co., Ltd., trade name: EL451) was diluted with a water / methanol = 1/4 solution to obtain a coating solution 5.
[0052]
<Adjustment of gas barrier coating layer solution>
A) High purity montmorillonite as an inorganic layered compound and polyvinyl alcohol (degree of polymerization 1700) as a water-soluble polymer were diluted with water so as to be 1: 1 in terms of weight to obtain a liquid A.
[0053]
B) A hydrolyzate of tetraethoxysilane (TEOS) as an additive was mixed with the A liquid so that A liquid / TEOS hydrolyzate = 6/4 in terms of weight to obtain B liquid.
[0054]
C) Polyvinyl alcohol (degree of polymerization 1700) as a water-soluble polymer was diluted with water to obtain a liquid C in which the inorganic layered compound was not mixed.
[0055]
  <referenceExample 1>
  As a base material 1, a 20 μm thick biaxially stretched surfactant-added polypropylene film (product name: U-1 manufactured by Tosero Co., Ltd.) is applied to the corona discharge treated surface, and the coating liquid 1 is gravure as an adhesion layer 2. The coated layer was applied and dried by passing through an oven at 80 ° C. to form an adhesion layer. Next, the liquid A was applied as a gas barrier coating layer 3 by a gravure coating method, passed through an oven at 80 ° C. and dried to form a gas barrier coating layer.,A plastic film laminate was obtained.
[0056]
  <referenceExample 2>
  referenceIn Example 1, the same except that the coating liquid 2 was used as the adhesion layer 2InA plastic film laminate was obtained.
[0057]
  <Example1>
  referenceA plastic film laminate of the present invention was obtained in the same manner except that the coating liquid 3 was used as the adhesion layer 2 in Example 1.
[0058]
  <Comparative example 1>
  referenceA plastic film laminate was obtained in the same manner except that the coating liquid 4 was used as the adhesion layer 2 in Example 1.
[0059]
  <Comparative example 2>
  referenceA plastic film laminate was obtained in the same manner except that the coating liquid 5 was used as the adhesion layer 2 in Example 1.
[0060]
  <Example2>
  A coating liquid 3 is applied as an adhesion layer 2 to a corona discharge-treated surface of a biaxially stretched surfactant-free polypropylene film (manufactured by Tosero Co., Ltd., trade name: M-1) having a thickness of 20 μm as a base material 1. It apply | coated by the gravure coat method and passed through 80 degreeC oven, and it dried and formed the contact | adherence layer. Next, the liquid A was applied as a gas barrier coating layer 3 by a gravure coating method, passed through an oven at 80 ° C. and dried to form a gas barrier coating layer, and a plastic film laminate of the present invention was obtained.
[0061]
  <Example3>
  A coating liquid 3 as an adhesion layer 2 is applied by a gravure coating method to a corona discharge-treated surface of a biaxially stretched polyethylene terephthalate film (trade name: P60, manufactured by Toray Industries, Inc.) having a thickness of 12 μm as a base material 1. The adhesive layer was formed by drying through an oven at 0 ° C. Next, the liquid A was applied as a gas barrier coating layer 3 by a gravure coating method, passed through an oven at 80 ° C. and dried to form a gas barrier coating layer, and a plastic film laminate of the present invention was obtained.
[0062]
  <Example4>
  As the base material 1, a coating liquid 3 was applied as an adhesion layer 2 to the corona discharge treated surface of a 15 μm thick biaxially stretched nylon film (trade name: ON-RT, manufactured by Unitika Ltd.) by a gravure coating method, It dried by passing through 80 degreeC oven and formed the contact | adherence layer. Next, the liquid A was applied as a gas barrier coating layer 3 by a gravure coating method, passed through an oven at 80 ° C. and dried to form a gas barrier coating layer, and a plastic film laminate of the present invention was obtained.
[0063]
  <Comparative Example 3>
  Example2In Example 1, except that the coating liquid 1 was used as the adhesion layer 2, a plastic film laminate was obtained in the same manner.
[0064]
  <Comparative example 4>
  Example3In Example 1, except that the coating liquid 1 was used as the adhesion layer 2, a plastic film laminate was obtained in the same manner.
[0065]
  <referenceExample3>
  referenceIn Example 1, the same except that the liquid B was used as the gas barrier coating layer 3InA plastic laminate was obtained.
[0066]
  <Comparative Example 5>
  referenceA plastic film laminate was obtained in the same manner except that the liquid C was used as the gas barrier coating layer 3 in Example 1.
[0067]
<Evaluation>
About each plastic film laminated body of an Example and a comparative example, (1) Gas barrier property coating-layer state, (2) Oxygen permeability (cc / m²(Day / atm), (3) cellophane tape adhesion, and (4) water resistance test.
[0068]
(1) Gas barrier coating layer state
The appearance of the coated film after drying was observed, and the film unevenness and pinholes were visually sensory evaluated.
[0069]
(2) Oxygen permeability
The oxygen permeability was measured under conditions of 30 ° C. and 70% RH using an oxygen permeability measuring device (manufactured by Modern Control, OXTRAN-10 / 50A).
[0070]
(3) Cellophane tape adhesion
A cellophane tape was applied to the coating surface of each plastic film laminate, and then peeled off. It was visually observed whether each layer was not peeled off.
[0071]
(4) Water resistance test
Each plastic film laminate was immersed in tap water at room temperature for 1 minute, and immediately after removal, the coated surface was gently wiped with a cloth, and the remaining state of the layer was visually confirmed.
[0072]
[Table 1]

[0073]
  referenceExample 12 and Example 1On the other hand, in Comparative Examples 1 and 2, since the main component is a water-soluble resin and the adhesion layer is formed, the adhesion layer is re-dissolved when the gas barrier coating layer is formed, resulting in poor appearance such as coating unevenness, and oxygen permeability. Rise and poor adhesion. Examples2~4On the other hand, in Comparative Examples 3 and 4, since no surfactant is added to the adhesion layer or the like, the formation state of the gas barrier coating layer is poor, pinholes are generated, and oxygen permeability is increased. Also,referenceIn Comparative Example 5 with respect to Example 1, since the montmorillonite is not contained in the gas barrier coating layer, an increase in oxygen permeability due to the humidity dependency peculiar to polyvinyl alcohol is observed,referenceExample3In this case, the addition of metal alkoxide improves water resistance while maintaining oxygen permeability. It can be said that those in the above examples are in a state where the gas barrier coating layer is in good condition and sufficiently practical as a gas barrier packaging material because of high oxygen permeability and high adhesion.
[0074]
【The invention's effect】
  As described above, according to the present invention, when an inorganic layered compound and a gas-barrier coating layer of a water-soluble polymer are applied to a substrate made of a plastic film, a polyurethane resin is a main component as an adhesion layer.DenseArrivalCationic system in the layerBy blending and forming a surfactant, it is possible to produce a plastic film laminate having high gas barrier properties that is practical as a packaging material.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a plastic film laminate of the present invention.
[Explanation of symbols]
1. Base material
2 ... Adhesion layer
3. Gas barrier coating layer

Claims (6)

On at least one surface of a substrate made of a plastic material, an adhesion layer to the polyurethane resin as a main component, a gas barrier coating layer to the inorganic layered compound and a water-soluble polymer as a main component are sequentially stacked, before Kimitsu plastic film laminate gas-barrier properties, characterized in that the wear layer contains a cationic surface active agent has been applied. The plastic film laminate according to claim 1, wherein a hydrolyzate of metal alkoxide is contained in the gas barrier coating layer. The plastic film laminate according to claim 1 or 2, wherein the metal constituting the metal alkoxide is Si, Al, or Ti. The plastic film laminate according to any one of claims 1 to 3, wherein the water-soluble polymer is a polyvinyl alcohol type or a derivative thereof. The interlayer distance of the inorganic layered compound in the gas barrier coating layer is 1.2 times or more larger than the interlayer distance of the inorganic layered compound before forming the gas barrier coating layer with the water-soluble polymer. The plastic film laminate according to any one of claims 1 to 4, wherein: 6. The plastic film laminate according to claim 1, wherein the inorganic layered compound is montmorillonite.

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