JP3482844B2 - Gas barrier transparent laminate - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate used for packaging foods, pharmaceuticals and other non-foods, and more particularly to a laminate used as a packaging material for packaging requiring sterilization by boiling.

[0002]

2. Description of the Related Art Packaging materials used for packaging foods, pharmaceuticals, and other non-foods contain oxygen, water vapor, and other substances in order to suppress alteration of the contents to be packaged and to retain their functions and properties. It is required to have a gas barrier property that blocks the permeation of gas that alters the contents.

Therefore, conventionally, as a gas barrier layer for imparting a gas barrier property to a packaging material, a packaging material using a metal foil made of a metal such as aluminum which is less affected by temperature, humidity and the like has been generally used.

However, a packaging material using a metal foil made of a metal such as aluminum has an excellent gas barrier property, but has a drawback that the contents cannot be seen through the packaging material and is used. There is also a drawback that the packaging material must be treated as an incombustible material when the packaging material is later discarded, and when the packaging material is used to package the contents, a metal detector is used for the inspection of the contents. There was also a drawback that you could not use.

Therefore, as a packaging material that overcomes these drawbacks, for example, US Pat.
No. 28017, etc., a vapor deposition film made of an inorganic oxide such as silicon oxide, aluminum oxide or tin oxide is formed on a polymer film by a forming means such as a vacuum vapor deposition method or a sputtering method. Vapor-deposited films have been developed. These vapor-deposited films have transparency and further have gas barrier properties against oxygen, water vapor, etc., so they are suitable as packaging materials having both transparency and gas barrier properties that cannot be obtained with metal foils and the like. It is said that.

[0006]

By the way, the above-mentioned vapor-deposited film is a vapor-deposited film alone in which a vapor-deposited film of an inorganic oxide is formed on a polymer film as a packaging material for packaging containers, packaging sheets and the like. Rarely used in. Usually, after the vapor deposition film is formed, as post-processing, various processes such as printing process to print letters, patterns, etc. on the film surface, laminating process with the film, etc., shape processing to a predetermined container shape etc. It is applied and used as a packaging material for packaging containers and packaging sheets. In addition, the packaging material may be subjected to sterilization treatment such as boiling sterilization.

Therefore, the packaging material made of a vapor-deposited film has a problem of deterioration in physical properties due to post-processing or sterilization treatment such as boiling sterilization. For example,
When a sealant film is attached to a vapor-deposited film that is a polymer film on which a vapor-deposited film made of an inorganic oxide is formed, bags are made, and then the contents are filled and sterilized by boiling, delamination is applied to a part of the seal part after sterilization. Is generated and the gas barrier property is deteriorated.

Therefore, so far, the transparency is such that the contents can be directly seen through, the high gas barrier property of blocking the gas or the like which affects the contents, and the gas barrier property even after boiled sterilization. The fact is that no packaging material suitable for a packaging material for boiling has been found, which has all of the boiling resistance such as no deterioration and no delamination.

The present invention is intended to solve the problems of the prior art as described above, and is a highly practical package having excellent transparency, high gas barrier properties, and no deterioration in physical properties even after boiling sterilization. Intended to provide material.

[0010]

You achieve the above Symbol object of SUMMARY OF THE INVENTION The present <br/> invention, on at least one surface of a substrate made of a transparent plastic material, a hydroxyl number of 5 to 200 (KOH mg /
g) an acrylic polyol and an isocyanate compound
The NCO group derived from the isocyanate compound is
Mixed so that it is 50 times or less than the OH group derived from riol
A transparent primer layer made of a mixture, depositing a thin film layer made of non-machine oxides, water-soluble polymer, (a) 1 or more gold
Genus alkoxide or its hydrolyzate, and (b) salt
Drying of an aqueous coating agent containing at least one of tin oxide
Gas barrier coating layer consisting of coating film, and biaxially stretched Niro
Film, biaxially oriented polyethylene terephthalate film
Transparent made of rum or biaxially oriented polypropylene film
A gas barrier transparent laminate comprising a plastic intermediate layer which is sequentially laminated and a polyolefin thermoplastic resin layer which is further laminated thereon as a seal layer.

Particularly, in this gas barrier transparent laminate, the inorganic oxide forming the vapor-deposited thin film layer is composed of aluminum oxide, silicon oxide or a mixture thereof, or the vapor-deposited thin film layer has a thickness of 5 to 300 nm. A certain aspect and an aspect in which the thickness of the transparent primer layer is 0.01 to 2 μm are provided.

A transparent plastic intermediate film made of a biaxially stretched nylon film, a biaxially stretched polyethylene terephthalate film or a biaxially stretched polypropylene film is provided between the vapor-deposited thin film layer of the gas barrier transparent laminate and the polyolefin thermoplastic resin layer. Water-soluble polymer, (a) one or more metal alkoxides or hydrolysates thereof, and (b) between the laminated layers and the vapor-deposited thin film layer and the polyolefin-based thermoplastic resin layer. Tin chloride, an aspect in which a gas barrier film layer composed of a dry coating film of an aqueous coating agent containing at least one of, and further, this gas barrier film layer and a transparent plastic intermediate layer are formed on the vapor-deposited thin film layer. A mode in which the layers are sequentially stacked is provided.

In the gas barrier transparent laminate of the present invention, a transparent primer layer made of a mixture of acrylic polyol and an isocyanate compound is laminated on a transparent plastic substrate, and a vapor deposition thin film layer made of an inorganic oxide is laminated thereon. ing. Here, the vapor-deposited thin film layer is provided as a gas barrier layer like the vapor-deposited film of the conventional vapor-deposited film,
Since the transparent primer layer has excellent interlayer adhesion and smoothness, it enhances the adhesion between the transparent plastic substrate and the deposited thin film layer. Therefore, the gas-barrier transparent laminate of the present invention can prevent the occurrence of delamination due to boiling sterilization and the reduction in gas-barrier property due to it. Further, the gas barrier transparent laminate of the present invention is excellent in transparency and becomes a highly practical packaging material that satisfies the boiling suitability.

Particularly, in the gas barrier transparent laminate of the present invention, a biaxially stretched nylon film, a biaxially stretched polyethylene terephthalate film or a biaxially stretched polypropylene film is provided between the vapor deposition thin film layer and the polyolefin thermoplastic resin layer. According to the embodiment in which the transparent plastic intermediate layer is laminated, the mechanical strength and the thermal stability are further enhanced, so that the packaging bag made of this laminate is crushed when subjected to treatment such as boil sterilization or retort sterilization. The strength is extremely high.

Further, in the gas barrier transparent laminate of the present invention, a water-soluble polymer and (a) at least one metal alkoxide or a hydrolyzate thereof are provided between the vapor-deposited thin film layer and the polyolefin-based thermoplastic resin layer. , And (b) tin chloride, the gas barrier film layer comprising a dry coating film of an aqueous coating agent containing at least one of the above, and a high gas barrier equivalent to the case where an aluminum foil is provided as the gas barrier layer. You can get sex.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view for explaining one embodiment of the gas barrier transparent laminate of the present invention.

The gas barrier transparent laminate 10 shown in FIG. 1 has a transparent primer layer 2, a vapor deposition thin film layer 3, a gas barrier film layer 4, a transparent plastic intermediate layer 5, and a polyolefin thermoplastic resin layer 6 on a substrate 1. It has a structure in which layers are sequentially stacked.

Here, the substrate 1 is made of a transparent plastic material. The degree of transparency of the transparent plastic material forming the base material 1 is not particularly limited as long as the contents to be packaged can be confirmed, but the transparency of the vapor-deposited thin film layer 3 is utilized and the shape of the contents to be packaged. The transmittance at wavelength of 350 nm is 60% so that colors and colors can be recognized accurately.
It is preferable to set it to a degree or more.

Examples of such transparent plastic materials include polyethylene terephthalate (PET),
Examples thereof include polyester films such as polyethylene naphthalate, polyolefin films such as polyethylene and polypropylene, polystyrene films, polyamide films, polyvinyl chloride films, polycarbonate films, polyacrylonitrile films, and polyimide films. These may be stretched or unstretched. Further, as the transparent plastic material, one having mechanical strength and dimensional stability is preferable. Therefore, among the films made of these transparent plastic materials, a polyethylene terephthalate film arbitrarily stretched in the biaxial direction is particularly preferable.

Various well-known additives and stabilizers such as an antistatic agent, an anti-UV agent, a plasticizer and a lubricant can be added to the base material 1. In order to improve the adhesion with the transparent primer layer 2, the base material 1 can be subjected to corona treatment, low temperature plasma treatment, ion bombardment treatment as pretreatment, and further subjected to chemical treatment, solvent treatment and the like. May be.

The thickness of the substrate 1 is not particularly limited, but the thickness suitability as a packaging material for the entire laminate 10 including other layers, the transparent primer layer 2 and the vapor deposition on the substrate 1. Considering workability when the thin film layer 3 and the gas barrier film layer 4 are formed, it is preferably 3 to 200 μm, and more preferably 6 to 30 μm in practical use.

From the viewpoint of mass productivity of the gas barrier transparent laminate 10, it is preferable to use a long film as the substrate 1 so that each layer can be continuously laminated thereon.

The transparent primer layer 2 laminated on the base material 1 enhances the adhesion between the base material 1 and the vapor deposited thin film layer 3,
It is provided to prevent the occurrence of delamination after boiling sterilization. In order to achieve such an object, the present invention requires that the transparent primer layer 2 be formed from a mixture of an acrylic polyol and an isocyanate compound.
That is, when a mixture of an acrylic polyol and an isocyanate compound is used as a material for forming the transparent primer layer 2, a urethane bond is formed by these reactions, so that each of the substrate 1, the transparent primer layer 2 and the vapor deposition thin film layer 3 is formed. The adhesion between layers can be improved.

Here, as the acrylic polyol, an acrylic resin containing a highly reactive vinyl monomer having a hydroxy group such as hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate or acrylate as a copolymerization component can be used. In this case, the hydroxyl value is 5 when considering the reactivity with the isocyanate compound to be mixed.
It is preferable to be set to 200 (KOHmg / g).

On the other hand, the isocyanate compound reacts with the acrylic polyol to form a urethane bond,
It mainly acts as a crosslinking agent or a curing agent. Examples of the isocyanate compound include aromatic tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), aliphatic xylene diisocyanate (XDI) and hexalene diisocyanate (HMDI).
Etc. can be used alone or as a mixture thereof.

The compounding ratio of the acrylic polyol and the isocyanate compound is not particularly limited, but if the isocyanate compound is too small, curing may be poor, and on the other hand, if it is too large, blocking or the like may occur to cause processing problems. Cause problems. Therefore, the compounding ratio of the acrylic polyol and the isocyanate compound is preferably such that the NCO group derived from the isocyanate compound is 50 times or less than the OH group derived from the acrylic polyol, and particularly the NCO group and the OH
It is preferable to mix the base and the group in an equivalent amount. A well-known method can be used as the mixing method, and there is no particular limitation.

The solvent used for preparing the mixture of the acrylic polyol and the isocyanate compound is not particularly limited as long as it can dissolve and dilute the resin formed from the mixture. For example, esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and aromatic hydrocarbons such as toluene and xylene may be used alone or in any combination. From the viewpoint of coating film processing and odor, a mixture of toluene and ethyl acetate is preferable.

In this mixture, various additives such as a curing accelerator such as a tertiary amine, an imidazole derivative, a metal salt compound of carboxylic acid, a quaternary ammonium salt and a quaternary phosphonium salt, a phenol type and a sulfur type are added. It is also possible to add a phosphite-based antioxidant, a leveling agent, a flow control agent, a catalyst, a crosslinking reaction accelerator, a filler and the like.

The thickness of the transparent primer layer 2 is not particularly limited as long as a coating film can be formed uniformly, but it is generally preferably in the range of 0.01 to 2 μm. If the thickness is less than 0.01 μm, it may be difficult to obtain a uniform coating film, and the adhesion may deteriorate. On the other hand, when the thickness exceeds 2 μm, it is difficult to maintain flexibility in the coating film because it is thick, and cracks may occur in the coating film due to external factors, which is not preferable. The particularly preferable thickness of the transparent primer layer 2 is in the range of 0.05 to 0.5 μm.

As a method of forming the transparent primer layer 2,
For example, a known printing method such as an offset printing method, a gravure printing method, or a silk screen printing method, or a known coating method such as roll coating, knife edge coating, or gravure coating can be used. Drying conditions after printing or coating can be those generally taken.

In the gas barrier transparent laminate 10 of FIG. 1, the vapor deposition thin film layer 3 laminated on the transparent primer layer 2 is formed of an inorganic oxide vapor deposition film. This deposited thin film layer 3
Has transparency and a gas barrier property against oxygen, water vapor and the like. The inorganic oxide forming the vapor-deposited thin film layer 3 is not particularly limited as long as the vapor-deposited thin film layer 3 is a transparent layer having a gas barrier property, and various inorganic oxides can be used, such as aluminum oxide and silicon oxide. Inorganic oxides such as tin oxide, tin oxide, magnesium oxide, or mixtures thereof can be used. Among these, aluminum oxide and silicon oxide are particularly preferable.

The vapor deposition thin film layer 3 may be formed on the transparent primer layer 2 by various methods for forming a vapor deposition film. For example, it can be formed by an ordinary vacuum vapor deposition method, and other thin film forming methods such as a sputtering method, an ion plating method, and a plasma vapor deposition method (C
It can also be formed by VD) or the like. However, in view of productivity, the vacuum vapor deposition method is currently the most excellent.
The heating means of the vacuum vapor deposition apparatus used in the vacuum vapor deposition method is preferably an electron beam heating method, a resistance heating method or an induction heating method. In addition, the transparent primer layer 2 of the vapor deposition thin film layer 3
It is also possible to use a plasma assist method or an ion beam assist method in order to improve the adhesion to the above and the denseness of the deposited thin film layer 3. In order to improve the transparency of the vapor-deposited thin film layer 3, reactive vapor deposition in which oxygen gas or the like is blown may be performed when the vapor-deposited film is formed.

The preferred thickness of the vapor-deposited thin film layer 3 varies depending on the type of the inorganic oxide used for its formation, etc., but is generally in the range of 5 to 300 nm, preferably 10 to 15.
0 nm is more preferable. If the film thickness is less than 5 nm, it is difficult to obtain a uniform vapor-deposited film, and the film thickness becomes insufficient, so that the function as a gas barrier layer may not be sufficiently fulfilled. On the contrary, when the film thickness exceeds 300 nm, it is difficult to maintain flexibility in the deposited film,
External factors such as bending and pulling may cause cracks in the deposited film.

In the gas-barrier transparent laminate 10 of FIG. 1, the gas-barrier coating layer 4 imparts the gas-barrier transparent laminate 10 with a gas barrier property as high as that of aluminum. It is stacked. Therefore, the formation of the gas barrier coating layer 4 may be omitted depending on the application of the gas barrier transparent laminate 10 and the like.

The gas barrier coating layer 4 is provided with a water-soluble polymer and (a) one kind as a constituent of the gas barrier coating layer 4 for imparting the gas barrier transparent laminate 10 with a gas barrier property as high as that of aluminum. It is preferably formed from a dry coating film of an aqueous coating agent containing at least one of the above metal alkoxide or its hydrolyzate and (b) tin chloride. More specifically, a water-soluble polymer and tin chloride are used as an aqueous solvent (water or a mixed solution of water and alcohol).
Or a water-soluble polymer and tin chloride are dissolved in an aqueous solvent, and then a solution in which a metal alkoxide or a hydrolyzate thereof is mixed is used as a coating agent, or a metal alkoxide or A coating agent is prepared by dissolving the hydrolyzate in an aqueous solvent. Then, the vapor deposition thin film layer 3 is coated with such a coating agent and heated and dried to form the gas barrier film layer 4 which greatly improves the gas barrier property of the gas barrier transparent laminate 10.

Next, each component contained in this coating agent will be described in more detail.

First, as the water-soluble polymer, polyvinyl alcohol, polyvinylpyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate and the like can be used. In particular, it is preferable to use polyvinyl alcohol (hereinafter referred to as PVA) from the viewpoint of improving the gas barrier property of the gas barrier transparent laminate of the present invention. In this case, as the PVA, those generally obtained by saponifying polyvinyl acetate can be used, and the degree of saponification is not particularly limited. Various types of PVA can be used, from so-called partially saponified PVA in which tens of percent of acetic acid groups remain, to complete PVA in which only a few percent of acetic acid groups remain.

Next, as the metal alkoxide of the component (a), tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ) and triisopropoxy aluminum [Al (O-2′-C ₃ H ₇ ) ₃ ] are used.
Such as M (OR) _n (where M is Si, Ti, A
and R is an alkyl group such as CH ₃ and C ₂ H ₅ ). Of these, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis. Further, hydrolyzates of these metal alkoxides can be used as the component (a), and stannous chloride (SnCl ₂ ) and stannic chloride (SnCl ₄ ) can be used as the tin chloride as the component (b). , Or a mixture thereof can be used. In addition, tin chloride may be used as an anhydride or a hydrate.

For the above-mentioned component (a) and component (b), one or both of them are used together with a water-soluble polymer.

The water-based coating agent for forming the gas-barrier coating layer 4 contains an isocyanate compound, a silane coupling agent, a dispersant, as long as the gas-barrier property is not impaired.
Known additives such as stabilizers, viscosity modifiers, and colorants can be added.

For example, the isocyanate compound added to the coating agent may be one having two or more isocyanate groups (NCO groups) in its molecule, and more specifically, tolylene diisocyanate (TDI). Monomers such as triphenylmethane triisoianate (TTI) and tetramethylxylene diisocyanate (TMXDI), and polymers and derivatives thereof can be used.

As a method of applying the aqueous coating agent for forming the gas barrier film layer 4, conventionally known means such as a dipping method, a roll coating method, a screen printing method and a spray method can be used.

The film thickness of the gas barrier film layer 4 varies depending on the type of coating agent used for its formation and processing conditions, but the film thickness after drying is preferably 0.01 to 50 μm. If the film thickness is less than 0.01 μm, the gas barrier property cannot be sufficiently improved, and the film thickness is 5
If it exceeds 0 μm, cracks are likely to occur in the film, which is not preferable.

In the gas-barrier transparent laminate 10 of FIG. 1, the transparent plastic intermediate layer 5 is formed as necessary in order to enhance the bag breaking strength during boil sterilization or retort sterilization. Therefore, the gas-barrier transparent laminate 1
The transparent plastic intermediate layer 5 may be
Formation is omitted.

As a constituent material of the transparent plastic intermediate layer 5 used for improving the bag breaking strength, a biaxially stretched nylon film, a biaxially stretched polyethylene terephthalate film or a biaxially stretched polypropylene is used from the viewpoint of mechanical strength and thermal stability. It is preferable to use a film. The thickness of the transparent plastic intermediate layer 5 is determined according to the material, required quality and the like, but it is generally preferably 10 to 30 μm. As a method for forming the transparent plastic intermediate layer 5, a known method such as a dry laminating method in which the above-mentioned films are attached using an adhesive such as a two-component curing type urethane resin can be used.

In the gas barrier transparent laminate 10 of FIG. 1, the polyolefin thermoplastic resin layer 6 is laminated as a seal layer used at an adhesive portion when the laminate 10 is formed into a bag-like package or the like. There is. Examples of the constituent material of the polyolefin-based thermoplastic resin layer 6 include polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, ethylene-acrylic acid copolymer. A polyolefin-based thermoplastic resin such as a polymer, an ethylene-acrylic acid ester copolymer and a metal cross-linked product thereof is used. Although the thickness of the polyolefin-based thermoplastic resin layer 6 is determined according to the purpose, it is generally 15 to 200.
It is preferably set to μm. As a method for forming the polyolefin-based thermoplastic resin layer 6, for example, a dry laminating method is used in which a film-shaped one made of the above-mentioned polyolefin-based thermoplastic resin is attached using an adhesive such as a two-component curable urethane resin. You can

Although the gas-barrier transparent laminate 10 shown in FIG. 1 has been described above, the gas-barrier transparent laminate of the present invention includes the layers constituting the gas-barrier transparent laminate 10 of FIG. And can have various layers.

For example, when the gas-barrier transparent laminate is put to practical use as a packaging bag or the like, it is preferable to provide a printed layer on the vapor-deposited thin film layer 3 or the gas-barrier film layer.
The printing layer is a urethane-based, acrylic-based, nitrocellulose-based, rubber-based, vinyl chloride-based, etc. ink binder resin that has been conventionally used, and various additives such as pigments, extender pigments, plasticizers, desiccants and stabilizers. Is a layer composed of an ink in which, for example, characters and pictures can be arbitrarily expressed. As a method for forming the print layer, for example, a known printing method such as an offset printing method, a gravure printing method, a silk screen printing method, or a known coating method such as roll coating, knife edge coating, or gravure coating can be used. The thickness of the printing layer is usually 0.1 to
The thickness is preferably 2.0 μm.

The gas barrier transparent laminate of the present invention is essential.
Not, that have the layers having the gas-barrier transparent laminate 10 of FIG. Therefore, unlike the laminate 10b shown in FIG. 2, the gas barrier film layer 4 and the transparent plastic intermediate layer 5 are not provided, and the transparent primer layer 2, the vapor deposition thin film layer 3 and the polyolefin thermoplastic resin layer are provided on the substrate 1. 6 embodiment and are sequentially stacked, and as the laminate 10c as shown in FIG. 3, no gas barrier coating layer 4, the substrate 1, a transparent primer layer 2, deposited thin film layer 3, the transparent plastic intermediate layer 5 A structure in which the polyolefin-based thermoplastic resin layer 6 is sequentially laminated, or without the transparent plastic intermediate layer 5 like the laminate 10d shown in FIG. 4, the substrate 1, the transparent primer layer 2, the vapor deposition thin film layer 3, gas barrier coating layer 4, a polyolefin-based thermoplastic resin layer 6 are sequentially laminated structure, the onset
It is not a clear gas barrier transparent laminate.

Further, each layer constituting the above-mentioned gas barrier transparent laminate can be formed not only on one surface of the substrate 1 but also on both surfaces.

[0052]

【Example】

Hereinafter, the present invention will be specifically described based on Examples. In addition, the following Examples 1-3 are substrate / transparent primer layer /
A specific example relates to a laminated body of the present invention comprising the depositing the thin film layer / gas barrier coating layer / transparent plastic intermediate layer / polyolefin-based thermoplastic resin layer, Example 1 is an unusual not been formed transparent plastic intermediate layer reference example 2 is unusual that has gas barrier coating layer is formed. Comparison
Examples 1 and 2 are examples in which the transparent primer layer is not provided.
Is.

Example 1 A gas barrier transparent laminate having the same layer structure as that of the gas barrier transparent laminate 10 of FIG. 1 was produced as follows.

First, a 12 μm-thick biaxially stretched polyethylene terephthalate (PET) film was used as the substrate 1, and a resin having the following composition was used as a transparent primer layer 2 on one side of the film by a gravure coating method so as to have a thickness of 0. It was formed to a thickness of 0.1 μm.

[Transparent Primer Layer Forming Resin Composition] Resin: acrylic polyol / isocyanate compound mixing ratio: OH group (acrylic polyol) / NCO group (isocyanate) = 1/1 (equivalent ratio) Dissolving solvent: toluene / ethyl acetate = 5/5

Next, silicon oxide is deposited on the transparent primer layer 2 to a thickness of about 40 nm by a resistance heating vacuum deposition apparatus.
To form a vapor-deposited thin film layer 3.

Further, an aqueous coating agent having the following composition was applied thereon by a bar coater and dried by a dryer at 120 ° C. for 1 minute to form a gas barrier film layer 4 having a thickness of 0.3 μm.

[Aqueous coating agent composition] The following liquid and liquid were mixed at a weight ratio of 60:40 Liquid: tetraethoxysilane 10.4 g and hydrochloric acid (0.1
N) 89.6 g was added, and the mixture was hydrolyzed by stirring for 30 minutes to give a solid content of 3 wt% (SiO ₂ conversion). Hydrolysis solution of polyvinyl alcohol 3 wt% water / isoprobe alcohol solution (water: isopropyl alcohol = 90: 1).
0 (weight ratio))

Then, as the transparent plastic intermediate layer 5, a biaxially stretched nylon film having a thickness of 15 μm is laminated by a dry lamination method with a two-component curing type urethane adhesive, and further, as a polyolefin thermoplastic resin layer 6. A low-density polyethylene film having a thickness of 40 μm was laminated with a two-component curing type urethane adhesive by a dry lamination method to obtain a gas barrier transparent laminate of the example.

Example 2 In Example 1, as the vapor-deposited thin film layer 3, metal aluminum was evaporated by a vacuum vapor deposition apparatus using an electron beam heating system, and oxygen gas was introduced into the vapor-deposited thin film layer 3 to form an aluminum oxide thin film layer having a thickness of 20 nm. A gas barrier transparent laminate of the example was obtained in the same manner as in the example 1 except that the transparent laminate was formed.

Example 3 In the same manner as in Example 1, except that the resin having the following composition was used to form the transparent primer layer 2 and the transparent primer layer 2 having a thickness of 0.2 μm was formed. A gas barrier transparent laminate of the example was obtained.

[Resin composition for forming transparent primer layer] Resin: acrylic polyol / isocyanate compound blending ratio: OH group (acrylic polyol) / NCO group (isocyanate) = 1/4 (equivalent ratio) Solvent: toluene / ethyl acetate = 5/5

Reference Example 1 A gas barrier transparent laminate of Reference Example was obtained in the same manner as in Example 1 except that the transparent plastic intermediate layer 5 was not provided.

Reference Example 2 A gas barrier transparent laminate of Reference Example was obtained in the same manner as in Example 1 except that the gas barrier coating layer 4 was not provided.

Comparative Example 1 A transparent laminate of Comparative Example was obtained in the same manner as in Example 1 except that the transparent primer layer 2 was not provided.

Comparative Example 2 A transparent laminate was obtained in the same manner as in Example 2 except that the transparent primer layer 2 was not provided.

Evaluation Using the laminates obtained in each of the examples and comparative examples, a four-way pouch used for sterilizing a boil was prepared, and water of 150 contents was used as the content.
g, and boil sterilization was performed at 90 ° C. for 30 minutes.
As evaluation items, (1) oxygen permeability before and after boiling (cc /
m ² / day), (2) Lamination strength (gr / 15 mm)
And (3) The occurrence of delamination after boil by visual observation was tested or observed as follows. The results are shown in Table 1.

(1) Oxygen permeability before and after boiling (cc / m ² /
Day): Measuring device: Oxygen permeability measuring device manufactured by Mocon Co., Ltd. Measuring condition: 30 ° C., 70% RH (2) Laminate strength (gr / 15 mm): Measuring device: Tensilon tensile tester Peeling speed: 300 mm / min Peeling angle: 180 ° (3) Delamination occurrence after boil by visual observation: Observation of floating parts etc. at seals etc.

[0069]

[Table 1]

From the results of Table 1, the laminates of Comparative Examples 1 and 2 are transparent enough to allow the contents to be directly seen through, and have a gas barrier property of blocking a gas or the like that affects the contents. it is inferior both after Boyle resistance Boyle be no occurrence of gas barrier properties of the deterioration or delamination GaWaka
It On the other hand, the laminated bodies of Examples 1 to 3 are transparent,
It can be seen that both the gas barrier property and the boiling resistance are excellent, and the suitability as a packaging material subjected to the boiling sterilization treatment is excellent. In addition, from Table 1, the product of Reference Examples 1 and 2
The layered body has a ratio of appearance and overall evaluation.
Although superior to the laminates of Comparative Examples 1-2, Examples 1-3
It can be seen that it is inferior to the laminated body of.

[0071]

EFFECT OF THE INVENTION The laminate of the present invention has excellent transparency, has a high gas barrier property similar to that of aluminum foil, and has general versatility. In particular, since the adhesion of each layer constituting the laminate is high, the suitability for boiling is excellent, and delamination due to boiling sterilization or the like is prevented. Therefore, the laminate of the present invention can be widely used in the packaging field.

[Brief description of drawings]

FIG. 1 is a layer configuration diagram of a gas barrier transparent laminate of the present invention.

FIG. 2 is a gas barrier transparent laminate not included in the present invention.
It is a layer configuration diagram of.

FIG. 3 is a gas barrier transparent laminate that is not included in the present invention.
It is a layer configuration diagram of.

FIG. 4 is a gas barrier transparent laminate which is not included in the present invention.
It is a layer configuration diagram of.

[Explanation of symbols]

1 Base Material 2 Transparent Primer Layer 3 Deposition Thin Film Layer 4 Gas Barrier Coating Layer 5 Transparent Plastic Intermediate Layer 6 Polyolefin Thermoplastic Resin Layer 10, 10b, 10c, 10d Gas Barrier Transparent Laminate

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsunenori Komori 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (56) Reference JP-A-3-231838 (JP, A) JP-A 3-278946 (JP, A) JP-A-61-103966 (JP, A) JP-A-6-106692 (JP, A) JP-A-7-164591 (JP, A) JP-A-8-267641 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B32B 1/00-35/00 C09J 1/00-201/10

Claims (6)

(57) [Claims] On at least one surface according to claim 1] made of a transparent plastic material substrate, and accession <br/> Lil polyol with an isocyanate compound of the hydroxyl number of 5~200 (KOHmg / g), isocyanate
Nate group derived from nate compound is derived from acrylic polyol
Transparent primer layer comprising a mixed mixture such that 50 times or less of OH groups, deposited thin film composed of non-machine oxides, water-soluble polymer, (a) 1 or more metal alkoxides also
At least its hydrolyzate and (b) tin chloride
A coating consisting of a dry coating of an aqueous coating agent containing
Sub barrier film layer, biaxially stretched nylon film,
Axial stretched polyethylene terephthalate film or biaxially stretched
In transparent plastic made of expanded polypropylene film
A gas-barrier transparent laminate, wherein interlayer layers are sequentially laminated, and a polyolefin-based thermoplastic resin layer is laminated thereon as a seal layer. 2. The gas barrier transparent laminate according to claim 1, wherein the inorganic oxide forming the vapor-deposited thin film layer comprises aluminum oxide, silicon oxide or a mixture thereof. 3. The gas barrier transparent laminate according to claim 1, wherein the vapor-deposited thin film layer has a thickness of 5 to 300 nm. 4. The transparent primer layer has a thickness of 0.01 to 2
The gas barrier transparent laminate according to claim 1, which has a thickness of μm. 5. A water-soluble polymer that forms the gas barrier coating layer, gas-barrier transparent laminate according to any one of claims 1 to 4 comprising a polyvinyl alcohol. 6. A metal alkoxide to form a gas barrier coating layer, tetraethoxysilane, triisopropoxyaluminum or gas-barrier transparent laminate according to any one of claims 1 to 5 consisting of a mixture thereof.