JP2011037116A - Method for manufacturing gas barrier film and gas barrier film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a gas barrier film with such advantages that an environmental impact by incineration disposal is insignificant, the process to make the film thin and lightweight is provided, the processing procedures of the film during its manufacturing are fewer in number, while ensuring a beautiful gloss, and the manufacturing cost is reduced, and also to provide a gas barrier film thereof. <P>SOLUTION: This method for manufacturing the gas barrier film comprises processes of: forming a printing layer on a surface film, a process to form a vapor deposition layer composed of metal on the printing layer; forming an adhesive layer on the vapor deposition layer, a process to bond a back film to the surface of the adhesive layer; forming the printing layer, a process to form the vapor deposition layer, a process to form the adhesive layer on the vapor deposition layer; and bonding the back side film on the adhesive layer. These processes to form the printing layer, to form the vapor deposition layer, and to form the adhesive layer are executed in a series of continuous processes. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a gas barrier film provided with a vapor deposition layer made of a metal such as aluminum, and a gas barrier film.

In general, a gas barrier film having a high gas barrier property is often used for a packaging film used as a packaging bag for food or the like.
As the gas barrier film, a film using aluminum as a gas barrier layer, which has high gas barrier properties such as oxygen and nitrogen, water vapor barrier properties, and excellent light shielding properties, is widely used.
Since aluminum has a high light reflectivity and a beautiful metallic luster, printing with a beautiful metallic luster in the background can be obtained by forming a printing layer on the surface side of the gas barrier layer made of aluminum.

As a gas barrier film using aluminum as a gas barrier layer, a film using aluminum foil as a gas barrier layer is known. (For example, see Patent Document 1 below)
However, those using aluminum foil have a problem that the environmental load during incineration is large, and in addition, it is difficult to reduce the film thickness and weight.

On the other hand, a gas barrier film using an aluminum vapor deposition layer instead of an aluminum foil as a gas barrier layer is also known.
FIG. 3 is a schematic cross-sectional view showing a gas barrier film using an aluminum vapor deposition layer.
The gas barrier film shown in FIG. 3 has a surface film (A), a printing layer (B), an adhesive layer (C), an aluminum vapor deposition layer (D), and a back film (E) laminated in this order. Is configured.

However, such a gas barrier film has a problem in that since the adhesive layer (C) is provided on the surface side of the aluminum vapor-deposited layer (D), the reflectance of light is lowered and it is difficult to obtain a beautiful gloss. there were.
Furthermore, this gas barrier film forms a printing layer (B) on the surface film (A), then applies an adhesive to form an adhesive layer (C), and further forms an aluminum vapor deposition layer (D) in advance. Since it was manufactured by laminating the prepared back film (E), there were also problems that the number of processing steps was increased and the manufacturing cost was increased.

JP 2003-136638 A

  The present invention has been made to solve the above-described problems of the prior art, has a low environmental load during incineration, can be made thinner and lighter, and has a beautiful gloss. In addition, the present invention provides a method for producing a gas barrier film and a gas barrier film, which are capable of reducing the production cost with fewer processing steps during production.

  The invention according to claim 1 includes a step of forming a printing layer on the surface film, a step of forming a vapor deposition layer made of a metal on the printing layer, a step of forming an adhesive layer on the vapor deposition layer, And a step of adhering a back film on the adhesive layer. The step of forming the printed layer, the step of forming the vapor deposition layer, and the step of forming the adhesive layer are a series of continuous processing steps. It is related with the manufacturing method of the gas barrier film characterized by performing by this.

  The invention according to claim 2 relates to a gas barrier film characterized in that a surface film, a printed layer, a vapor deposition layer made of metal, an adhesive layer, and a back film are laminated in this order.

According to the first aspect of the present invention, after forming the printing layer on the surface film, the vapor deposition layer made of metal is formed on the printing layer, and then the adhesive layer is formed on the vapor deposition layer. An adhesive layer does not intervene between the vapor deposition layer and the vapor deposition layer, and a gas barrier film having a beautiful metallic luster on the background of printing can be obtained.
Moreover, compared with the manufacturing method of the conventional gas barrier film which provides an adhesive bond layer on the surface side of an aluminum vapor deposition layer, a process process can be reduced and it becomes possible to reduce manufacturing cost.
Furthermore, since the process of forming a printing layer, the process of forming a vapor deposition layer, and the process of forming an adhesive layer are performed in a continuous series of processing steps, the production efficiency can be greatly improved.

According to the invention which concerns on Claim 2, since a surface film, a printing layer, the vapor deposition layer which consists of metals, an adhesive bond layer, and a back film are laminated | stacked in this order, a surface film and a vapor deposition layer An adhesive layer is not interposed between the two, and a gas barrier film having a beautiful metallic luster on the background of printing is obtained.
Moreover, since the vapor deposition layer which consists of a metal can be formed thinly compared with the gas barrier film using an aluminum foil, the environmental load at the time of an incineration process is small, and the film thickness reduction and weight reduction are attained.

It is a schematic sectional drawing which shows the gas barrier film which concerns on this invention. It is a schematic block diagram which shows an example of the apparatus for performing a printing layer formation process, a vapor deposition layer formation process, and an adhesive bond layer formation process by a continuous series of processing processes. It is a schematic sectional drawing which shows an example of the conventional gas barrier film.

Hereinafter, preferred embodiments of a method for producing a gas barrier film and a gas barrier film according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing a gas barrier film according to the present invention.
The gas barrier film according to the present invention includes a surface film (1), a printing layer (2), a vapor deposition layer (3) made of metal, an adhesive layer (4), and a back film (5). It is comprised by laminating | stacking in order.

A surface film (1) is a film which forms the surface of the gas barrier film which concerns on this invention.
Examples of the material of the surface film (1) include biaxially stretched polypropylene (OPP), biaxially stretched polyethylene terephthalate (PET), unstretched polypropylene (CPP), stretched polystyrene (OPS), high density polyethylene, medium density polyethylene, Low density polyethylene, linear low density polyethylene (LLDPE), biaxially stretched nylon (ONY), unstretched nylon (CNY) and the like are preferably used.
Also, PVDC coat OP in which OPP is coated with polyvinylidene chloride (PVDC), PVA coat OP in which OPP is coated with PVA (vinylon) resin, and the like can be used. By using these, the gas barrier property can be further enhanced.
Although the thickness of a surface film (1) is not specifically limited, For example, you may be 12-50 micrometers.

  The printing layer (2) is a layer formed on the back side of the surface film (1), and is formed by a known printing method such as gravure printing, flexographic printing, offset printing, screen printing, transfer printing or the like.

A vapor deposition layer (3) is a gas barrier layer formed by vapor-depositing a metal on the printed layer (2) side of the surface film (1).
Aluminum (Al) is most preferably used as a metal for forming the vapor deposition layer (3), but tin (Sn), indium (In), indium tin oxide (ITO), zinc (Zn), silver (Ag). Other types of metals such as may be used.
Although the thickness of a vapor deposition layer (3) is not specifically limited, For example, you may be 300-500 mm.

An anchor coat layer (not shown) is provided between the printing layer (2) and the vapor deposition layer (3) as necessary.
As the anchor coating agent for forming the anchor coating layer, for example, an anchor coating agent such as polyurethane, polyester urethane, vinyl chloride-vinyl acetate copolymer system, acrylic copolymer system or the like can be used.
Although the thickness of an anchor coat layer is not specifically limited, For example, you may be 1-3 micrometers.

The adhesive layer (4) is a layer formed on the back side of the vapor deposition layer (3).
Adhesives for forming the adhesive layer (4) include polyurethane, polyester, polyester-polyurethane, polyether-polyurethane, acrylic, vinyl, polyamide, epoxy, rubber and other adhesives. Can be used.
Although the thickness of an adhesive bond layer (4) is not specifically limited, For example, you may be 1-3 micrometers.

A back film (5) is a film which forms the back surface of the gas barrier film which concerns on this invention.
Examples of the material of the back film (5) include biaxially stretched polypropylene (OPP), biaxially stretched polyethylene terephthalate (PET), unstretched polypropylene (CPP), stretched polystyrene (OPS), high density polyethylene, medium density polyethylene, Low density polyethylene, linear low density polyethylene (LLDPE), biaxially stretched nylon (ONY), unstretched nylon (CNY) and the like are preferably used. Although the thickness of a back film (5) is not specifically limited, For example, you may be 30-150 micrometers.

The gas barrier film according to the present invention has a layer structure of “surface film / printing layer / deposition layer / adhesive layer / back film” as described above.
Specific layer configurations of the gas barrier film according to the present invention include “OPP20 / printing layer / deposition layer / adhesive layer / CP40”, “PET12 / printing layer / deposition layer / adhesive layer / LLD40”, “PET12”. / Printing layer / deposition layer / adhesive layer / LLD50 ”and the like can be exemplified, but the present invention is not limited to these configurations. In addition, the numerical value described in the layer structure has shown thickness (micrometer).

Next, the manufacturing method of the gas barrier film according to the present invention will be described.
The method for producing a gas barrier film according to the present invention includes a step of forming a printed layer on a surface film (printed layer forming step) and a step of forming a vapor deposited layer made of metal on the printed layer (deposited layer forming step). And a step of forming an adhesive layer on the vapor deposition layer (adhesive layer forming step), and a step of bonding a back film on the adhesive layer (back surface film bonding step).

In the manufacturing method which concerns on this invention, a printing layer formation process, a vapor deposition layer formation process, and an adhesive bond layer formation process are performed by a continuous series of processing processes.
FIG. 2 is a schematic configuration diagram illustrating an example of an apparatus for performing a printing layer forming step, a vapor deposition layer forming step, and an adhesive layer forming step in a continuous series of processing steps. Hereinafter, the printing layer forming step, the vapor deposition layer forming step, and the adhesive layer forming step of the manufacturing method according to the present invention will be described with reference to FIG. 2, but in the present invention, it is not always necessary to use the apparatus shown in FIG. Alternatively, other devices may be used as long as at least the above three steps can be performed in a continuous series of processing steps.

  The apparatus shown in FIG. 2 includes an unwinding unit (10), a printing unit (20), a vacuum deposition chamber (30), a roll coater (40), a drying chamber (50), and a winding unit (60).

The unwinding part (10) winds the surface film (1) in a roll shape, and the surface film (1) is unwound from the unwinding part (10) and supplied to the printing part (20).
A printing part (20) forms a printing layer (2) on the back surface of a surface film (1) by well-known printing methods, such as gravure printing, flexographic printing, offset printing, screen printing, and transfer printing.

The surface film (1) after the printing layer (2) is formed in the printing unit (20) is introduced into the vacuum deposition chamber (30).
The vacuum deposition chamber (30) includes an introduction / extraction section (31) through which a film is introduced and taken out, a plurality of decompression sections (32), a deposition section (33) in which a deposition layer is formed, a decompression section (32), And an exhaust means (34) for depressurizing the vapor deposition section (33).

  The decompression section (32) is a small room provided to increase the degree of vacuum in stages, and between individual decompression sections, between the decompression section and the introduction / extraction section (31) or the vapor deposition section (33). Are partitioned by sheet roll groups (35) arranged in multiple stages. A deflector roll (36) for applying tension to the film is disposed in the middle of the upper and lower sheet roll groups (35).

The vapor deposition section (33) is provided with equipment for forming a vapor deposition layer in the vacuum chamber, and is maintained in a high vacuum state by the exhaust means (34).
In the vapor deposition section (33), a cooling roll (331) that supports the film and cools from the back surface thereof, a crucible (332) that is disposed below the cooling roll (331) and contains a vapor deposition material, and a crucible (332) ) Is heated to evaporate the vapor deposition material.

The surface film (1) introduced into the vacuum deposition chamber (30) is continuously introduced from the introduction / extraction section (31) under atmospheric pressure, and the degree of vacuum is increased stepwise by the plurality of decompression sections (32). Then, it is introduced into the vapor deposition section (33) in a vacuum state. The surface film (1) introduced into the vapor deposition section (33) is wound around the cooling roll (331), and the vapor deposition material evaporated from the crucible (332) by heating by the heating means is the surface opposite to the cooling roll (331) ( A vapor deposition layer (3) is formed by vapor deposition on the printed layer side surface.
The film after the vapor deposition layer (3) is formed is taken out from the vapor deposition section (33), and the degree of vacuum is gradually reduced through the plurality of decompression sections (32), and then the introduction / extraction section (31). And is taken out from the vacuum deposition chamber (30).

The film taken out from the vacuum deposition chamber (30) is sent to the roll coater (40).
The roll coater (40) forms an adhesive layer (4) by continuously applying an adhesive on the vapor deposition layer (3) formed on the printed layer (2) side of the surface film (1). For example, a gravure roll coater or a reverse roll coater can be used.

The film on which the adhesive layer (4) is formed by the roll coater (40) is sent to the drying chamber (50).
The drying chamber (50) generates high-temperature (usually 80 to 120 ° C.) gas and / or airflow (wind) from a heat source, and evaporates the solvent contained in the adhesive applied by the roll coater (40). dry.
The film from which the adhesive has been dried by the roll coater (40) is once wound on the roll of the winding unit (60).

As described above, the production efficiency can be improved by performing the printing layer forming step, the vapor deposition layer forming step, and the adhesive layer forming step in a series of continuous processing steps using an apparatus as shown in FIG. It becomes possible.
That is, after forming a vapor deposition layer with a conventional vapor deposition apparatus, when forming an adhesive layer with another apparatus such as an extrusion lamination apparatus, the vapor deposition layer forming process and the adhesive layer forming process are performed on different dates. However, in the present invention, the manufacturing efficiency can be greatly improved by performing these steps in a continuous series of processing steps (performing each step without taking time between the steps).

In the case where an anchor coat layer is provided between the printing layer (2) and the vapor deposition layer (3), an anchor coat layer is provided between the printing unit (20) and the vacuum vapor deposition chamber (30) in the apparatus shown in FIG. An anchor coat coater is provided.
In this case, the film on which the printing layer (2) is formed in the printing section (20) is sent to the anchor coat coater to form the anchor coating layer on the printing layer (2), and then the vacuum deposition chamber ( 30), the vapor deposition layer (3) is formed on the anchor coat layer.

  In the back film bonding step, the film wound up around the winding section (60) is continuously unwound and is unwound from another roll (not shown) onto the adhesive layer (4) of the film. The film (5) is adhered. As a bonding method, a dry laminating method is preferably used, but is not limited thereto, and other known bonding methods may be used.

The gas barrier film according to the present invention having the configuration shown in FIG. 1 is obtained through the printing layer forming step, the vapor deposition layer forming step, the adhesive layer forming step, and the back surface film adhering step described above.
In the gas barrier film thus obtained, no adhesive layer (4) is interposed between the surface film (1) and the vapor deposition layer (3). Therefore, it becomes a gas barrier film having a beautiful metallic luster of the vapor deposition layer (3) on the background of the printing layer (2).

Examples of the gas barrier film according to the present invention are shown below. However, the present invention is not limited to the following examples.
Example 1
As a gas barrier film having a layer structure consisting of “surface film / print layer / anchor coat layer / evaporation layer / adhesive layer / back film”, the surface film is PVDC coat OP (trade name: KOP) (thickness 20 μm), Using the apparatus shown in FIG. 2, the anchor coat layer is urethane resin + nitrified cotton resin, the vapor deposition layer is aluminum, the adhesive layer is a solvent-free urethane adhesive, and the back film is CPP (thickness 40 μm). The film of Example 1 was produced by the method. In addition, the printing layer was made into two types, what provided the base layer which consists of white ink (with white), and those which did not provide (without white).
(Example 2)
A film having the same layer structure as that of Example 1 except that the surface film is made of OPP (thickness 20 μm) was produced by the above production method using the apparatus shown in FIG.
(Example 3)
A film having the same layer configuration as that of Example 1 except that the surface film is made of PVA coat OP (trade name: AOP) (thickness 20 μm) is manufactured by the above manufacturing method using the apparatus shown in FIG. Film.
Example 4
A film having the same layer structure as in Example 1 except that the surface film is made of PVA coat OP (trade name: XOP) (thickness: 20 μm) is manufactured by the above manufacturing method using the apparatus shown in FIG. Film.

<Measurement of water vapor transmission rate>
The water vapor permeability of the films of Examples 1 to 4 was measured according to JIS K7129. The measurement conditions were 40 ° C. × 90% RH.
<Measurement of oxygen permeability>
The oxygen permeability was measured for the films of Examples 1 to 4 in accordance with JIS K7126-1. The measurement conditions were 20 ° C. × 90% RH.

Table 1 shows the measurement results of water vapor permeability and oxygen permeability.
In Table 1, the catalog values of water vapor permeability and oxygen permeability of KOP film, AOP film, and XOP film are shown as Reference Examples 1, 3, and 4, respectively.

As shown in Table 1, when comparing Example 1 and Reference Example 1, Example 3 and Reference Example 3, Example 4 and Reference Example 4, respectively, the water vapor permeability and oxygen permeability of the film of the Example are The value was much smaller than that of the reference example.
From this result, it was confirmed that the barrier film according to the present invention has excellent water vapor barrier properties and oxygen barrier properties.

<Gelbo test>
A gelbo test (50 times) was performed on the films of Examples 1 to 4. Gervo environmental conditions were 20 ° C. × 63% RH. Table 2 shows the measurement results of water vapor permeability and oxygen permeability for the film before the test (initial stage) and after the test.
In Table 2, water vapor permeability and oxygen permeability measured for films (OPP20 / PE10-15 / AL VM-PET12 / CPP20-25) used in commercially available potato chips (Calby) packaging bags. These values are also shown as a reference example.

As shown in Table 2, the surface films of the examples composed of KOP, AOP, and XOP (Examples 1, 3, and 4) were superior in oxygen barrier properties after the gelbo test compared to the reference examples. The value was inferior in terms of water vapor barrier properties.
Although the surface film of the example consisted of KOP, AOP, and XOP (Examples 1, 3, and 4), the water vapor permeability and the oxygen permeability were not significantly decreased before and after the test, but the surface film was OPP. The sample (Example 2) had a significant decrease in oxygen permeability.
From this result, it was confirmed that when a film having a coating layer such as a PVDC coat was used as the surface film, a gas barrier film having excellent bending resistance was obtained.

  The gas barrier film according to the present invention is suitably used as a material film for packaging bags for containing foods, cosmetics, detergents, shampoos and the like.

DESCRIPTION OF SYMBOLS 1 Front film 2 Print layer 3 Deposition layer 4 Adhesive layer 5 Back film

Claims (2)

Forming a printed layer on the surface film;
Forming a deposited layer made of metal on the printed layer;
Forming an adhesive layer on the deposited layer;
A process of adhering a back film on the adhesive layer,
A method for producing a gas barrier film, wherein the step of forming the printed layer, the step of forming the vapor deposition layer, and the step of forming the adhesive layer are performed in a continuous series of processing steps.   A gas barrier film comprising a surface film, a printed layer, a vapor deposition layer made of a metal, an adhesive layer, and a back film laminated in this order.

Images