JPH09314728A - Gas barrier laminated film bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an inside visible and to have high barrier properties by fusion-bonding an aluminum foil laminated film and the marginal part of a transparent film having a thin film layer of the oxide of one kind of an element selected from silicon, aluminum, and magnesium together. SOLUTION: A gas barrier laminated film bag is made by fusion-bonding an aluminum foil laminated film and a transparent laminated film having a thin film together. In the thin film layer of the transparent laminated film, which is required to shut off gas such as oxygen and steam while keeping transparency, a substance which forms the thin film layer is made at least the oxide of a kind of element selected from among silicon, aluminum, and magnesium. To seal as a bag, fusion bonding layers are formed in the innermost layers of the transparent laminated film having the thin film layer and the aluminum foil laminated film, and the peripheral parts are fusion-bonded to each other by a hot plate heat sealing method etc.

Description

Detailed Description of the Invention

[0001]

The present invention relates to foodstuffs, pharmaceuticals,
The present invention relates to a gas barrier laminated film bag which has a high gas barrier property in the fields of electronic parts, works of art, precision machine parts, etc. and which allows confirmation of the packaging contents.

[0002]

2. Description of the Related Art When a plastic laminated film is used as a packaging material, generally, two plastic laminated films are heat-sealed around each other and used as a bag. Conventionally, in the case of a packaging material that requires a high gas barrier property, a film obtained by laminating an aluminum foil has been used.
However, a packaging material using such an aluminum foil has a drawback that it is opaque and the contents cannot be seen from the outside, although it has excellent gas barrier properties. On the other hand, vinylidene chloride, a vinylidene chloride resin film composed of a copolymer containing vinylidene chloride as a main component,
And vinylidene chloride resin-coated films obtained by coating these vinylidene chloride resins on polypropylene, polyester, and polyamide are generally used as packaging materials having gas barrier properties, but these gas barrier properties are not sufficient, and high gas barrier properties. It was unsuitable for packaging materials that require good properties.

Further, polyvinyl alcohol films such as polyvinyl alcohol films and ethylene-vinyl alcohol copolymer films are widely used as packaging materials because of their excellent oxygen barrier properties, but they are inferior in water vapor barrier properties. It has a drawback that the oxygen barrier property is also lowered under the condition of high humidity. In addition, a film obtained by vapor-depositing silicon oxide on a biaxially stretched nylon film or a biaxially stretched polyester film (Japanese Patent Publication No. 53-1295).
3), polyethylene terephthalate film, a film obtained by vapor deposition of magnesium oxide on a biaxially oriented polypropylene film (Japanese Patent Laid-Open No. 60-27532), and the like have been proposed. These vapor deposition films also have gas barrier properties, particularly water vapor barrier properties. Was not sufficient and was insufficient for applications requiring high gas barrier properties.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a packaging bag which has a high gas barrier property and whose inside is visible.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above drawbacks, the present inventors have found that an aluminum foil laminated film and at least one element selected from silicon, aluminum and magnesium are oxidized. By using a gas barrier laminated film bag formed by heat-sealing the peripheral portions of a transparent laminated film having a thin film layer of a product, a gas barrier laminated film bag having a transparent and extremely high barrier property is obtained. The present invention has been accomplished and the present invention has been achieved.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The gas barrier laminate film bag of the present invention comprises a bag produced by heat-sealing two different types of films, one of which is an aluminum foil laminate film, The other type of film is a transparent laminated film having a thin film layer.

The aluminum foil used in the aluminum foil laminated film of the present invention is not particularly limited as long as it is used in a general packaging aluminum foil laminated film. When the thickness of the aluminum foil is too thin, there is a problem of pinholes, and when it is too thick, there are problems of cost and flexibility, so that the thickness of 3 to 20 μm is preferably used.

The substrate film used for the transparent laminated film having the thin film layer of the present invention is not particularly limited as long as it is a transparent plastic film, but it is a film made of polyolefin such as polyethylene, polypropylene or polybutene, polyethylene terephthalate, polyethylene. -2
A film made of polyester such as 6-naphthalate,
Examples thereof include films made of polyamide such as nylon 6 and nylon 12, films made of polycarbonate, polyvinyl alcohol, polyvinyl butyral and the like. Further, these films may be a single layer or a laminated film composed of different resins, and known additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant, and a colorant are added to the raw material resin. It may be one. The base film is
From the viewpoint of strength, elongation and thermal characteristics, a stretched film is preferable, but an unstretched film may be used. Furthermore, on the surface of the base film, prior to forming the thin film layer,
It may be subjected to surface treatment such as corona discharge treatment, flame treatment, plasma treatment, glow discharge treatment, surface roughening treatment, or anchor coating treatment using a known anchor coating agent.

There is no particular limitation on the thickness of the base film used for the transparent laminated film having a thin film layer used in the present invention, and those having a thickness in the range of 3 to 400 μm can be suitably used, but the mechanical strength and From the point of flexibility, 5-2
It is preferably in the range of 00 μm.

Since the thin film layer of the transparent laminated film having the thin film layer of the present invention needs to block gases such as oxygen and water vapor while maintaining transparency, the substance forming the thin film layer is silicon, aluminum or magnesium. It is necessary to be an oxide of at least one element selected from the above.

In the transparent laminated film having a thin film layer of the present invention, it is necessary to provide the above thin film layer on at least one surface of the base plastic film. As a method for forming the thin film layer, a conventionally known method such as a vacuum vapor deposition method, an ion plating method, a sputtering method and a CVD method can be adopted.

In the present invention, the thickness of the thin film layer formed on at least one of the base films of the transparent laminated film having the thin film layer varies depending on the material forming the thin film layer, the base material, etc. Generally 300-3000
Å thickness is preferred, more preferably 400-1500
Å. This is because if the thickness of the thin film layer is less than 300Å, the gas barrier property is poor due to insufficient film thickness, and if it exceeds 3000Å, cracks due to bending or the like are likely to occur.

The aluminum foil laminated film used in the present invention has both sides of the aluminum foil, and the transparent laminated film having a thin film layer is newly provided to protect the aluminum foil and the thin film layer on at least the surface provided with the thin film layer. It is necessary to laminate another transparent film. The film to be laminated is not particularly limited as long as it is transparent,
Examples of the film include polyolefin resins such as polyethylene and polypropylene, vinylidene chloride resins, polyester resins such as polyethylene terephthalate. The thickness of the film to be laminated can be selected in the range of 5 to 200 μm according to the application.

Further, it is necessary to provide a heat-sealing layer as the innermost layer of the transparent laminated film and the aluminum foil laminated film having a thin film layer for sealing as a bag. Examples of transparent films that can be used as the heat-sealing layer include known heat-sealing films such as low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, polypropylene, and ionomer. Further, the transparent film used as the heat-sealing layer can also be used as a protective film for the thin film layer.

When laminating such another film, a known method such as a dry laminating method using a urethane adhesive, an acrylic adhesive, a polyester adhesive or the like and an extrusion laminating method are used. I can.

As a method for producing a bag using the gas barrier laminate film of the present invention, a generally used bag-making method by heat fusion is used. Specifically, a hot plate heat sealing method, a rotating roll sealing method, and a belt are used. The sealing method, the impulse sealing method, the high frequency welder sealing method, and the ultrasonic sealing method are exemplified. In addition, in the packaging method using the gas barrier laminate film of the present invention, a bag prepared in advance may be used, or the bag may be packaged while being formed.

In the gas barrier laminated film bag of the present invention, a gas absorbent such as a desiccant, an oxygen scavenger, a carbon dioxide absorbent or an acidic gas absorbent can be used. The bag can exert its function more effectively.

[0018]

The present invention will be described below in more detail with reference to specific examples of the present invention. In addition, the test method of the physical-property value in the following examples is shown. Oxygen transmission rate: The heat-sealing layer surface of the test film is used as the inner surface, and three sides are heat-sealed to prepare a 220 mm × 300 mm gas barrier laminated film bag. After replacing the inside of this gas barrier laminated film bag with nitrogen,
1 and put the last side that is not heat-sealed by heat-sealing and leave it in a thermo-hygrostat at 40 ° C and 95% RH to adjust the oxygen concentration inside the bag with time by Shimadzu GC It was measured by -14A type gas chromatography. The oxygen transmission rate was calculated from the obtained change in oxygen concentration. Water vapor transmission rate: The heat-sealing layer surface of the test film is set to the inner surface, and three sides are heat-sealed to produce a 100 mm × 100 mm gas barrier laminated film bag. 10 g of silica gel was put in the gas barrier laminated film bag and then sealed,
It was left in a thermo-hygrostat at 40 ° C. and 95% RH, and the weight of the entire bag was measured over time. The moisture permeability was calculated from the obtained weight change.

Example 1 Polyethylene terephthalate (PET) having a thickness of 12 μm
A transparent vapor-deposited film in which a silicon oxide thin film layer is formed on one surface of the film ["MOS-T" manufactured by Oike Kogyo Co., Ltd.]
R ”) vapor-deposited surface is coated with a urethane adhesive [manufactured by Toyo Morton Co., Ltd.] at 3.3 g / m ² to form an adhesive layer,
A 100 μm LLDPE film [“TUX-FCD” manufactured by Tohcello Co., Ltd.) was laminated on the adhesive layer. As a result, the transparent vapor deposition film / LLDPE with the PET surface facing outside
A two-layer laminated film of the film was obtained. Similarly, 3.3 g / m ² of urethane adhesive is applied to both sides of the aluminum foil having a thickness of 12 μm to form an adhesive layer, and a PET film having a thickness of 12 μm is laminated on the adhesive layer. A 100 μm LLDPE film was laminated on the adhesive layer on the opposite side. This allows PET film / aluminum foil /
A three-layer laminated film of LLDPE film was obtained. These LLDPE surfaces of the transparent laminated film having a thin film layer and the aluminum foil laminated film were used as inner surfaces, and three sides were heat-sealed to produce bags of 220 × 300 mm and 100 × 100 mm. The oxygen barrier rate and the moisture permeability of the obtained gas barrier laminated film bag were measured by the methods described above. Table 1 shows the results.

Example 2 Instead of the silicon oxide vapor-deposited transparent film (“MOS-TR” manufactured by Oike Kogyo KK) of Example 1, a thickness of 12 μm was used.
In the same manner as in Example 1 except that a transparent vapor-deposited film [“VM-PET1011” manufactured by Toyo Metalizing Co., Ltd.] in which an aluminum oxide thin film layer is formed on one surface of the PET film was used, oxygen permeability, The water vapor transmission rate was measured.
Table 1 shows the results.

Example 3 A transparent vapor-deposited film having a silicon oxide thin film layer formed on one side of a polyvinyl alcohol (PVA) film having a thickness of 12 μm (“Tech Barrier S” manufactured by Mitsubishi Chemical Corporation).
3.3g / m ² of urethane-based adhesive is applied on both sides to form an adhesive layer, and 20μ is applied to the adhesive layer on the silicon oxide vapor deposition layer side.
m oriented polypropylene (OPP) film is laminated,
An LLDPE film was laminated on the opposite surface. As a result, a three-layer laminated film of OPP film / PVA side transparent vapor deposition film / LLDPE film was obtained. Oxygen permeability and moisture permeability were measured in the same manner as in Example 1 except that this film was used in place of the two-layer laminated film of the transparent vapor deposition film / LLDPE film with the PET surface outside in Example 1. Table 1 shows the results.

Comparative Example 1 Oxygen permeability and moisture permeability were measured in the same manner as in Example 1 except that the transparent vapor-deposited laminated film used in Example 1 was used instead of the aluminum laminated film of Example 1. Table 1 shows the results.

Comparative Example 2 A 15 μm film of nylon coated with vinylidene chloride [“N8100AE” manufactured by Toyobo Co., Ltd.] 0.55 g / m ² of urethane adhesive (manufactured by Toyo Morton Co., Ltd.) as an anchor coating agent 20 μm laminated polyethylene film (made by Nippon Unicar “800
8 ") and a 60 μm linear low-density polyethylene film by the extrusion laminating method [“ TU manufactured by Tohcello Co., Ltd. ”
X-TC "] was laminated to obtain a three-layer laminated film. With respect to the obtained three-layer laminated film, oxygen permeability and moisture permeability were measured in the same manner as in Example 1. Table 1 shows the results.

[0024]

[Table 1]

[0025]

According to the present invention, it is possible to obtain a packaging bag which is transparent and has a gas barrier property against oxygen, water, carbon dioxide, corrosive gas and the like which cannot be achieved by the conventional transparent plastic film. Therefore, it is very useful as a packaging bag having a high gas barrier property and capable of confirming the packaging contents in the fields of foods, pharmaceuticals, electronic parts, arts, precision machine parts and the like.

Claims (1)

[Claims] 1. An aluminum foil laminated film and silicon,
A gas barrier laminated film bag obtained by heat-sealing peripheral portions of a transparent laminated film having a thin film layer which is an oxide of at least one element selected from aluminum and magnesium.