JP2022077216A - Oxygen-barrier laminated film - Google Patents

Abstract

To provide a laminated film which is a film having a metal-deposited layer and is excellent in oxygen barrier property.SOLUTION: There is provided an oxygen-barrier laminated film 10A formed by laminating: a stretched polyvinyl alcohol-based resin layer 12; and a vapor deposited film 14 having a metal-deposited layer 14b. The vapor deposited film having the metal-deposited layer is excellent in vapor barrier property, however, has insufficient oxygen barrier property. The polyvinyl alcohol-based resin layer, on the other hand, is excellent in oxygen barrier property, and the oxygen barrier property of the polyvinyl alcohol-based resin layer is further enhanced since the polyvinyl alcohol-based resin layer is stretched, therefore, the polyvinyl alcohol-based resin layer 12 can exhibit an extremely excellent oxygen barrier property by recoupling the oxygen barrier property of the vapor deposited film.SELECTED DRAWING: Figure 1

Description

The present invention relates to a laminated film having a metal vapor deposition layer and having excellent oxygen barrier properties.

As is well known, a thin-film film having a metal-deposited layer is excellent in blocking properties (barrier properties) of various gases such as oxygen gas and water vapor (Patent Document 1).

However, although the thin-film film having the metal-deposited layer is extremely excellent in water vapor barrier property, it cannot be said that the oxygen barrier property is sufficient.

Japanese Unexamined Patent Publication No. 2018-52551

Therefore, an object of the present invention is to provide a laminated film having a metal vapor deposition layer and having excellent oxygen barrier properties.

That is, the invention according to claim 1 is an oxygen barrier laminated film characterized in that it is formed by laminating a stretched polyvinyl alcohol-based resin layer and a vapor-filmed film having a metal-deposited layer.

Next, the invention according to claim 2 is the oxygen barrier laminated film according to claim 1, wherein the polyvinyl alcohol-based resin layer is laminated on the stretched base film.

Next, the invention according to claim 3 is characterized in that the base film and the polyvinyl alcohol-based resin layer are stretched in the same direction by stretching the base film coated with the polyvinyl alcohol-based resin. The oxygen barrier laminated film according to claim 2.

Next, the invention according to claim 4 is characterized in that the stretched polyvinyl alcohol-based resin film and the stretched base film are laminated via an adhesive layer. It is a laminated oxygen barrier film.

Next, the invention according to claim 5 is the oxygen barrier laminated film according to any one of claims 1 to 4, wherein the metal vapor deposition layer is composed of an aluminum vapor deposition layer.

Next, the invention according to claim 6 is characterized in that the thin-film deposition film comprises a non-stretched film as a vapor-filming substrate and a metal vapor-deposited layer laminated on the vapor-deposited substrate. The oxygen barrier laminated film according to any one of 5.

As described above, the thin-film film having a metal-deposited layer is excellent in water vapor barrier property, but is not sufficient in oxygen barrier property. On the other hand, the polyvinyl alcohol-based resin layer has an excellent oxygen barrier property, and since the polyvinyl alcohol-based resin layer is stretched, the oxygen barrier property is further improved. It supplements the oxygen barrier property and exhibits extremely excellent oxygen barrier property.

FIG. 1 is an explanatory cross-sectional view showing an example of the oxygen barrier laminated film of the present invention. FIG. 2 is an explanatory cross-sectional view showing another example of the oxygen barrier laminated film of the present invention.

Hereinafter, specific examples of the present disclosure will be described with reference to the accompanying drawings. FIG. 1 is an explanatory cross-sectional view showing a first example of the oxygen barrier laminated film of the present invention.

As can be seen from FIG. 1, the laminated film 10A is configured by adhering two types of films with an adhesive layer 15 and laminating them.

Of the two types of films constituting the laminated film 10A, one of the films is composed of a base film 11, a polyvinyl alcohol-based resin layer 12, and a printing layer 13. In this film, first, a polyvinyl alcohol-based resin was applied to the base film 11 to form a polyvinyl alcohol-based resin layer 12, and then the film was stretched to simultaneously stretch the base film 11 and the polyvinyl alcohol-based resin layer 12. It is a thing. Therefore, the base film 11 and the polyvinyl alcohol-based resin layer 12 are stretched in the same stretching direction and at the same stretching ratio. The print layer 13 is printed and formed on the surface of the stretched polyvinyl alcohol-based resin layer 12.

The base film 11 may be any plastic film. For example, polyester film, polyethylene film, polypropylene film, polystyrene film, nylon film, polycarbonate film, polyacrylic nitrile film, polyimide film and the like.

Further, as the polyvinyl alcohol-based resin layer 12, a polyvinyl alcohol resin or a derivative thereof can be used. For example, it is a copolymer resin of ethylene and vinyl alcohol.

Further, of the two types of films constituting the film 10A, the other film is a thin-film deposition film 14 formed by laminating a metal vapor-film deposition layer 14b on a vapor-film deposition substrate 14a.

Any film can be used as the vapor-deposited substrate 14a. It may be a single-layer structure film or a multi-layer structure film.

As the single-layer structure film, for example, a polyester film, a polyethylene film, a polypropylene film, a polystyrene film, a nylon film, a polycarbonate film, a polyacrylic nitrile film, a polyimide film and the like can be used. A stretched film may be used, but a non-stretched film can be preferably used. For example, unstretched polypropylene film.

Further, as the film having a multilayer structure, it is possible to use a film in which the above-mentioned single-layer film is laminated.

As a typical example of the metal-deposited layer 14b, an aluminum-deposited layer can be mentioned. Of course, it may be a thin-film deposition layer of another metal. For example, copper, silver, etc.

The metal vapor deposition layer 14b can be formed on the surface of the vapor deposition substrate 14a by using a vacuum process such as a vacuum vapor deposition method, a sputtering method, or a plasma chemical vapor deposition method.

The polyvinyl alcohol-based resin layer 12 is laminated, and the stretched base film 11 and the vapor-deposited film 14 can be adhered to each other by the adhesive layer 15. As the adhesive constituting the adhesive layer 15, a general-purpose dry laminating adhesive can be used. It is desirable that the base film 11 is arranged so that the polyvinyl alcohol-based resin layer 12 faces the vapor-deposited film 14, and the metal-deposited layer 14b of the vapor-film-deposited film 14 faces the polyvinyl alcohol-based resin layer 12. It is desirable to arrange them in such a way. The illustrated example is a film 10A in which each film is arranged and laminated so that the adhesive layer 15 is in contact with both the polyvinyl alcohol-based resin layer 12 and the metal vapor-deposited layer 14b.

In this film 10A, the polyvinyl alcohol-based resin layer 12 is laminated on the vapor-deposited film 14, and since the polyvinyl alcohol-based resin layer 12 is stretched, the lack of oxygen barrier property of the vapor-deposited film 14 is stretched. The polyvinyl alcohol-based resin layer 12 supplements. Therefore, the oxygen barrier property of the vapor-filmed film 14 is greatly improved while keeping the high water vapor barrier property.

Next, FIG. 2 is an explanatory cross-sectional view showing a second example of the oxygen barrier laminated film of the present invention.

The oxygen barrier film 10B is different from the first example in that the polyvinyl alcohol-based resin film 12'formed separately from the base film 11 is used as the polyvinyl alcohol-based resin layer.

The base film 11 is stretched, and the polyvinyl alcohol-based resin film 12'is also stretched, but the stretching step of the base film 11 and the stretching step of the polyvinyl alcohol-based resin film 12'are also separate from each other. It is done independently. Therefore, the stretching direction of the base film 11 and the stretching direction of the polyvinyl alcohol-based resin film 12'can be different from each other. Further, the draw ratio of the base film 11 and the draw ratio of the polyvinyl alcohol-based resin film 12'can be different from each other. Although the stretching direction and stretching ratio of the base film 11 and the stretching direction and stretching ratio of the polyvinyl alcohol-based resin film 12'can be the same, it is difficult to make them exactly the same.

The base film 11 and the polyvinyl alcohol-based resin film 12'can be adhesively laminated with the adhesive layer 16. As the adhesive constituting the adhesive layer 16, a general-purpose dry laminating adhesive can be used.

Regarding other points, the laminated film 10B according to the second example is the same as the laminated film 10A according to the first example.

(Example 1)
An unstretched polyethylene terephthalate film is used as the base film 11, and a polyvinyl alcohol resin is applied thereto to form a polyvinyl alcohol-based resin layer 12, and then the base film 11 and the polyvinyl alcohol-based resin layer 12 are stretched. And were stretched at the same time.

Further, an unstretched polypropylene film (CPP) was used as the thin-film deposition base material 14a, and aluminum was vacuum-deposited on the unstretched polypropylene film (CPP) to form a metal-deposited layer 14b.

Then, the polyvinyl alcohol-based resin layer 12 and the metal-deposited layer 14b were adhesively laminated using a dry-laminate adhesive so as to face each other, and the laminated film according to Example 1 was manufactured.

(Example 2)
A biaxially stretched polyethylene terephthalate film was used as the base film 11. Further, as the polyvinyl alcohol-based resin layer, a polyvinyl alcohol resin film 12'that was formed and stretched separately from the base film 11 was used. Then, these films 11 and 12'were bonded and laminated to each other using a dry laminating adhesive.

Further, the same vapor-filmed film 14 as that of the vapor-filmed film 14 of Example 1 was used. That is, an unstretched polypropylene film (CPP) was used as the base material 14a, and aluminum was vacuum-deposited on the unstretched polypropylene film (CPP) to form a metal-deposited layer 14b, thereby forming the vapor-deposited film 14.

Then, the polyvinyl alcohol-based resin layer 12 and the metal-deposited layer 14b were adhesively laminated using a dry-laminate adhesive so as to face each other to produce a laminated film according to Example 2.

(Comparative Example 1)
Instead of the thin-film deposition film 14, a non-stretched polypropylene film (CPP) without a metal vapor deposition layer was used. Regarding other points, the laminated film of Comparative Example 1 was produced in the same manner as in Example 1.

(Comparative Example 2)
The laminated film of Comparative Example 2 was produced in the same manner as in Example 1 except that the base film 11 without the polyvinyl alcohol-based resin layer 12 was used without applying the polyvinyl alcohol resin.

(evaluation)
For the laminated films of Examples 1 and 2 and Comparative Examples 1 and 2, the oxygen permeability (trade name: OXTRAN-2 / 20, manufactured by MOCON) was used to measure the oxygen permeability (cm ³ / (m ² ). day · MPa))) was measured. The measurement results are shown in Table 1. In the table, "film adhesion" means that the polyvinyl alcohol resin film 12'produced separately from the base film 11 is adhered to the base film 11.

As can be seen from this result, in Comparative Example 1 which has a metal vapor deposition layer but does not have a polyvinyl alcohol-based resin layer, its oxygen permeability is relatively high and does not exhibit sufficient oxygen barrier properties.

On the other hand, in Examples 1 and 2 having the polyvinyl alcohol-based resin layer stretched together with the metal vapor-deposited layer, the oxygen permeability is suppressed to a low level and excellent oxygen barrier property is exhibited. Moreover, the polyvinyl alcohol-based resin layer is formed by applying the polyvinyl alcohol-based resin to the base film, or the polyvinyl alcohol resin film 12'produced separately from the base film 11 is adhered to the base film 11. It does not depend on whether it was formed by

In Comparative Example 2 which has a polyvinyl alcohol-based resin layer but does not have a metal vapor deposition layer, its oxygen permeability is the highest. Therefore, in order to exhibit sufficient oxygen barrier properties, a stretched polyvinyl alcohol-based resin layer is required. It can also be understood that both the metal vapor deposition layer and the metal vapor deposition layer are required.

10A, 10B: Oxygen barrier laminated film 11: Base film 12: Polyvinyl alcohol resin layer 12': Polyvinyl alcohol resin film 13: Printing layer 14: Vapor film 14a: Vapor base 14b: Metal vapor deposition layer 15: Adhesive Agent layer 16: Adhesive layer

Claims (6)

An oxygen barrier laminated film characterized by being formed by laminating a stretched polyvinyl alcohol-based resin layer and a vapor-filmed film having a metal-deposited layer. The oxygen barrier laminated film according to claim 1, wherein the polyvinyl alcohol-based resin layer is laminated on the stretched base film. The oxygen barrier laminating according to claim 2, wherein the base film and the polyvinyl alcohol-based resin layer are stretched in the same direction by stretching the base film coated with the polyvinyl alcohol-based resin. the film. The oxygen barrier laminated film according to claim 2, wherein the stretched polyvinyl alcohol-based resin film and the stretched base film are laminated via an adhesive layer. The oxygen-barrier laminated film according to any one of claims 1 to 4, wherein the metal-deposited layer is composed of an aluminum-deposited layer. The oxygen-barrier laminated film according to any one of claims 1 to 5, wherein the thin-film vapor-deposited film comprises a non-stretched film as a thin-film vapor-deposited base material and a metal-deposited layer laminated on the thin-film-deposited film. ..

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