JP2002361778A - Gas barrier film, its laminate and their manufacturing methods - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas barrier film having high gas barrier properties and excellent transparency and to provide its laminate. SOLUTION: The gas barrier film comprises a transparent thin film layer containing 2 to 64 atomic % of an oxygen, 0.5 to 56 atomic % of a nitrogen, 0.5 to 55 atomic % of a silicon and 5 to 80 atomic % of an aluminum and formed on at least one surface of a plastic film. Here, a total concentration of the oxygen, the nitrogen, the silicon and the aluminum is 30 to 100 atomic %. The film may be further converted into a laminate obtained by further coating a polyolefin film layer on the transparent thin film layer, and both are the most suitable for a packaging container material for containing a drug.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent film having a high gas barrier property, a laminate thereof, and a method for producing the same. The present invention relates to laminates and methods for producing the same.

[0002]

BACKGROUND OF THE INVENTION Pharmaceuticals, especially infusions, have conventionally been stored and stored in glass containers in order to maintain their quality for a long period of time. Recently, there has been a gradual shift to the use of plastic containers due to demands for weight reduction, compactness, and improvement in impact resistance. However, plastic containers generally have a higher permeability of gas such as oxygen and water vapor than glass containers, and therefore a plastic container having more excellent gas barrier properties is required.

In recent years, in order to reduce the permeability of plastic products for gases such as oxygen and water vapor, for example, Japanese Patent Laid-Open No. 5-83
No. 18 discloses that silica (SiO _x ) or alumina (Al) is formed on a polyester film by utilizing a vacuum evaporation method, a sputtering method, or a chemical vapor deposition method (CVD).
_Ox ) Various films formed with a thin film have been proposed. Since some of such films have good transparency, there is a possibility that a container having transparency suitable for confirming the storage state of the content liquid may be formed therefrom. However, containers for pharmaceuticals that require strict quality assurance require extremely high gas barrier properties, and thus are required to be further improved to further enhance the barrier performance of gases such as oxygen and water vapor.

[0004]

Accordingly, an object of the present invention is to provide a gas barrier film having high gas barrier properties and excellent transparency, and a laminate thereof. Another object of the present invention is to provide a gas barrier film suitable for a container and packaging material for pharmaceuticals such as an infusion which requires a high gas barrier property, and a laminate thereof. Further, the present invention is to provide a method for producing such a gas barrier film and a laminate.

[0005]

That is, according to the present invention, at least one surface of a plastic film has an oxygen concentration of 2 or less.
-64 atomic%, nitrogen concentration 0.5-56 atomic%, silicon concentration 0.5-55 atomic%, and aluminum concentration 5-80
A transparent thin film layer of atomic% is formed, wherein the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to
It relates to a gas barrier film which is 100 atomic%.

The plastic film is preferably a film formed of at least one resin selected from the group consisting of polyester, polyamide, ethylene / vinyl alcohol copolymer, polyolefin, and polyimide. The conductive film is suitable for a packaging container material for storing a medicine.

The present invention also relates to a gas barrier film laminate wherein the transparent thin film layer of the gas barrier film is further covered with a polyolefin film layer, wherein the transparent thin film layer and the polyolefin film layer are:
It is desirable that the layers are laminated via an anchor coat agent layer. Such a laminate is also suitable for a packaging container material for storing a medicine.

[0008] The present invention further provides a plastic film comprising at least one material selected from the group consisting of aluminum, aluminum oxide and aluminum nitride and a group consisting of silicon, silicon oxide and silicon nitride on at least one surface thereof. And a vacuum deposition of a combination with at least one material selected from the group consisting of oxygen and / or nitrogen, if necessary, whereby the oxygen concentration is 2 to 64 atomic% and the nitrogen concentration is 0. .5-56
Forming a transparent thin film layer consisting of at.%, A silicon concentration of 0.5 to 55 at.%, And an aluminum concentration of 5 to 80 at.
Here, the present invention relates to a method for producing a gas barrier film in which the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to 100 atomic%.

[0009] The vapor deposition material may be a combination of aluminum and silicon, a combination of aluminum nitride and silicon, at least one material selected from the group consisting of silicon oxide and silicon nitride, or a combination of aluminum or aluminum oxide and nitride. The combination with silicon is preferable, and the vacuum deposition is performed under the condition that plasma is generated by introducing nitrogen gas into the system, or nitrogen ions are generated near the surface of the plastic film by introducing nitrogen gas into the system. It is desirable to be performed under the following conditions.

Further, the present invention relates to a method for producing a gas barrier film laminate in which a gas barrier film is produced by the above-mentioned method, and then a polyolefin film is bonded to the transparent thin film layer via an anchor coat agent.

[0011]

DETAILED DESCRIPTION OF THE INVENTION Next, the structure of the gas barrier film and the laminate thereof according to the present invention and the method for producing them will be specifically described.

Gas Barrier Film The gas barrier film of the present invention comprises a plastic thin film serving as a substrate and a transparent thin film layer mainly composed of oxygen, nitrogen, silicon and aluminum on a gas barrier layer. It was formed as

The plastic film as the substrate is preferably a film having high transparency and flexibility.
Examples of such a film include polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyamide films such as nylon 6 and nylon 66, films of ethylene-vinyl alcohol copolymer, and polyolefin films such as polyethylene and polypropylene. A film or a polyimide film is preferred.

Among them, films manufactured from polyethylene terephthalate (PET), polyethylene naphthalate, nylon 6, and ethylene / vinyl alcohol copolymer (sold by Kuraray Co., Ltd. under the trade name “EVAL”) It is more preferable because it has excellent physical properties such as transparency, gas barrier properties, and mechanical strength. These films may be stretched films, or may be unstretched films,
Further, a laminated film in which two different kinds of films are combined may be used, and a blended film in which those resins are mixed may be used. The thickness of the film is usually 5 to 200
μm, preferably 10 to 50 μm.

The composition of the transparent thin film layer has an oxygen concentration of 2 to 2.
64 at%, preferably 18 to 40 at%, nitrogen concentration 0.5 to 56 at%, preferably 2 to 20 at%, silicon concentration 0.5 to 55 at%, preferably 3 to 32 at%,
And an aluminum concentration of 5 to 80 atomic%, preferably 5
-45 atomic%. Here, the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to 10
0 atomic%, preferably 36 to 100 atomic%. Other elements mainly include carbon. Note that the composition can be analyzed using a technique such as X-ray photoelectron spectroscopy or Auger electron spectroscopy.

When the composition is within the above range, the thin film layer is amorphous, exhibits high gas barrier properties, and has excellent transparency. The thickness of the thin film layer is usually 1
When the thickness is within the range of 0 to 500 nm, preferably 20 to 150 nm, the thin film layer has flexibility, so that it is difficult to crack and a high gas barrier effect can be maintained.

Such a transparent thin film layer may be provided on one side or both sides of a plastic film as a substrate. That is, it may be a two-layer structure of plastic film / transparent thin film layer, or a three-layer structure of transparent thin film layer / plastic film / transparent thin film layer. When the transparent thin film layers are formed on both sides, the gas barrier performance may be further enhanced as compared with the case of forming one side. For example, higher gas barrier properties may be obtained by distributing the thickness of the thin film layer on both sides than by forming a thick thin film layer on one side. When a transparent thin film layer is formed on both surfaces, the type and thickness of each thin film layer can be appropriately changed.

This gas barrier film is colorless and transparent, and hardly differs from the transparency and hue of the plastic film as the substrate. A commercially available gas barrier film having a silica thin film formed on the surface of a PET film has transparency but is colored yellow, making it difficult to confirm the storage state of the contents when used as a packaging container material. .

For evaluating the transparency of a film, for example, JIS
The visible light transmittance measurement method specified in R3106 is suitable, and the evaluation of yellowness can be performed by measuring the parallel light transmittance on the short wavelength side. The visible light transmittance of the gas barrier film obtained by the present invention is almost the same as that of the PET film, but the visible light transmittance of the silica thin film-forming film is 3 to 4% lower than that of the PET film. Further, when the parallel light transmittance of the silica thin film-formed film is measured on the short wavelength side of about 380 to 400 nm, it shows a remarkably low value. Since the gas barrier film according to the present invention is colorless and transparent as described above, it is suitable as a material for forming a packaging container for which the status of the contents needs to be confirmed.

Gas Barrier Film Laminate Such a gas barrier film can be used as it is, but its thin film layer may be coated with an organic polymer film layer to be converted into a laminate. In the case of a laminate, the surface coating layer protects the transparent thin film layer,
Alternatively, effects such as adding another property such as heat sealing property to the gas barrier film and further improving the gas barrier property can be expected. Such a surface coating layer is not particularly limited as long as it is formed of a film suitable for the above-mentioned purpose, but it is preferable to provide a layer of a polyolefin film such as a polyethylene film or a polypropylene film. Further, another polymer film or metal layer may be laminated on the surface of the substrate film opposite to the thin film layer.

When laminating a polyolefin film or the like on the thin film layer surface side or the opposite substrate film surface side,
By providing an adhesive layer between the layers, both layers can be firmly joined. As the adhesive, an anchor coating agent or a carboxylic acid-modified polyolefin can be used, and a urethane-based or isocyanate-based anchor coating agent used in a dry lamination method, and a maleic acid-modified polyolefin used in an extrusion lamination method are preferable. In particular, use of an anchor coat agent is desirable.

The gas barrier film or the above-mentioned laminate can be used as a four-layered body, a six-layered body, a seven-layered body, etc. by sequentially laminating them. Further, a laminate having a structure in which the gas barrier films are joined together may be used. The bonding surface at that time may be any of the base film, the transparent thin film, the base film and the transparent thin film. Among such laminates, the plastic film layer /
A laminate having a four-layer structure of a transparent thin film layer / anchor coating agent layer / polyolefin film layer, and a polyolefin film layer / anchor coating agent layer / transparent thin film layer / plastic film layer / transparent thin film layer / anchor coating agent layer / polyolefin film The seven-layered laminated body is preferable because of its simple structure and high gas barrier performance.

The oxygen permeability of the gas barrier film and the laminate thereof described above may be 0.1 to 2.5 (cc) as shown in the examples described later. / M ² · day · atm) and the laminate is 0.5 (cc / m ² · day · atm)
It can be seen that it has a very high gas barrier property as shown below. Furthermore, since it also has excellent transparency, it can be used for hermetic packaging of various articles using the same.

For example, one or two laminates having the structure of plastic film layer / transparent thin film layer / anchor coating agent layer / polyolefin film layer are placed on top of each other so that the polyolefin film layers face each other inward.
When the periphery is heat-sealed to have a container shape, it can be suitably used as a liquid storage container.

Method for Producing Gas Barrier Film The method for producing a gas barrier film according to the present invention comprises:
This is a dry process of forming a transparent thin film layer mainly composed of oxygen, nitrogen, silicon and aluminum on a plastic film as a substrate in a vacuum vessel system. Specifically, a transparent thin film layer is easily formed on at least one surface of a plastic film from a thin film layer forming material by applying a method such as a vacuum evaporation method, a sputtering method, and a chemical vapor deposition method (CVD). can do. Among them, the vacuum deposition method is a preferable method because the film formation rate is high and the productivity is high.

As the vapor deposition material, at least one material selected from the group consisting of aluminum, aluminum oxide, and aluminum nitride, and silicon, silicon oxide,
And a combination with at least one material selected from the group consisting of silicon nitride.

Examples of preferable material combinations are as follows. (1) Combination of aluminum nitride and silicon or silicon oxide (2) Combination of aluminum or aluminum oxide and silicon nitride (3) Combination of aluminum nitride and silicon nitride (4) Combination of aluminum and silicon

Of these, a combination of aluminum and silicon, a combination of aluminum nitride and silicon, a combination of aluminum and silicon nitride, and a combination of aluminum nitride and silicon nitride are particularly preferred.

The evaporation material may be heated after mixing a plurality of types, or each material may be heated separately in the same system. For example, when materials having similar melting points are used in combination, the former can be used, and when there is a difference in melting points, the respective transparent thin film layers can be formed by the latter. As a heating method of the evaporation material, a resistance heating method, an electron beam method, or the like can be used, and a suitable heating method may be selected depending on the type of the material, and the same method may be employed in the same system, Different methods may be used.

A required amount of oxygen may be supplied into the system, or oxygen remaining in a film forming reaction vessel (vacuum chamber) or a plastic substrate may be used, or may be taken from water vapor or the like. You may. Alternatively, reactive vapor deposition may be performed by introducing nitrogen as a reactive gas into the system. When a nitride is not used as a deposition material, nitrogen is required as a reactive gas. When conditions for generating nitrogen plasma or conditions for irradiating the vicinity of the surface of the plastic substrate with nitrogen ions are employed, it becomes easier to more effectively introduce nitrogen into the transparent thin film layer. When irradiating with nitrogen plasma or nitrogen ions, applying a negative bias to the plastic substrate makes it easier to introduce nitrogen more effectively.

Prior to the formation of the transparent thin film layer, the surface of the plastic film may be subjected to corona discharge treatment, glow discharge treatment, or other surface treatment, whereby the thin film layer is firmly joined to the plastic film surface. In addition, a thin film having a uniform thickness can be formed.

According to such a method, at least one surface of the plastic film has an oxygen concentration of 2 to 64 at%, a nitrogen concentration of 0.5 to 56 at%, and a silicon concentration of 0.5 to 5 at%.
A colorless and transparent thin film layer of 5 atomic% and an aluminum concentration of 5 to 80 atomic% can be easily formed.
Here, the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to 100 atomic%, preferably 36 to 100 atomic%.

The method of manufacturing the laminate The gas barrier film thus manufactured is
A laminate can be manufactured by coating and bonding a polymer film, for example, a polyolefin film on the surface of the transparent thin film layer. When the transparent thin film layer and the polymer film can be directly bonded, the coating material may be directly extruded and laminated on the gas barrier film. An adhesive resin, for example, a carboxylic acid-modified polyolefin resin may be extruded and laminated with the molecular film.

A more preferred method is a method called dry lamination, in which an anchor coating agent, for example, a urethane-based or isocyanate-based adhesive is applied on a polymer film to be a coating layer using a gravure coater or the like to form an anchor coating agent layer. By forming and pressing a transparent thin film layer of a gas barrier film on the layer, the two can be firmly joined. This dry lamination method is similarly applied to the case where another film is bonded to the surface of the gas barrier film opposite to the transparent thin film layer side, or the gas barrier film or a laminate thereof is bonded to each other. Can be.

[0035]

Next, the present invention will be described through examples.
The present invention is not limited by these examples.

Example 1 A transparent thin film layer having a thickness of 50 nm was formed on a PET film having a thickness of 12 μm by vacuum evaporation using silicon having a purity of 99.999% and aluminum nitride having a purity of 99.9%. Formed. As a heating method, a resistance heating method was used for silicon, and an electron beam heating method was used for aluminum nitride. During the vapor deposition, a nitrogen gas was circulated to generate plasma by a 13.56 MHz high frequency power supply (power 300 W) to obtain a transparent gas barrier film.

Next, a urethane anchor coating agent (Takelac A-606 (adhesive), trade name, Takeda Pharmaceutical Co., Ltd.) and Takenate A-10 (cured) were coated on a low-density linear polyethylene film having a thickness of 60 μm using a gravure coater. Agent)) was applied so as to be 66 (cc / m ² ). Thereafter, the coated surface was dried using a dryer at 80 ° C., and the anchor coating agent layer was adhered to the transparent thin film layer side of the gas barrier film obtained earlier to prepare a transparent gas barrier film laminate.

(Example 2) Silicon nitride having a purity of 99.5% and a purity of 99.5% were formed on a PET film having a thickness of 12 µm.
Vacuum deposition was performed using 999% aluminum as a deposition material to form a transparent thin film layer having a thickness of 80 nm. As a heating method, a resistance heating method was used for aluminum, and an electron beam heating method was used for silicon nitride. During vapor deposition, nitrogen gas was ionized and irradiated near the surface of the PET film as a substrate. Next, the transparent gas barrier film thus obtained was dry-laminated with a low-density linear polyethylene film via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

Example 3 On a PET film having a thickness of 12 μm, silicon having a purity of 99.999% and a purity of 9
Vacuum evaporation was performed using 9.999% aluminum as an evaporation material to form a transparent thin film layer having a thickness of 50 nm. As a heating method, a resistance heating method was used for aluminum, and an electron beam heating method was used for silicon. During deposition, nitrogen gas is passed
Plasma was generated by a 3.56 MHz high frequency power supply (power 300 W). A low-density linear polyethylene film was dry-laminated with the transparent gas barrier film thus obtained via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

(Example 4) Silicon nitride having a purity of 99.5% and a purity of 99.5% were formed on a PET film having a thickness of 12 µm.
Vacuum evaporation was performed using 9% aluminum nitride as an evaporation material to form a transparent thin film layer having a thickness of 60 nm. As a heating method, silicon nitride and aluminum nitride were put into a tungsten hearth at a weight ratio of 1: 1 and an electron beam heating method was used. During deposition, a nitrogen gas was circulated and 13.56 M
The plasma was generated by a high frequency power supply of 400 Hz (power 400 W). A low-density linear polyethylene film was dry-laminated with the transparent gas barrier film thus obtained via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

(Comparative Example 1) 99.9% pure SiO ₂ and 99.9% pure PET were formed on a PET film having a thickness of 12 μm.
Vacuum deposition was performed using 99% α-Al ₂ O ₃ as a deposition material to form a transparent thin film layer having a thickness of 50 nm. As a heating method, a resistance heating method was used for silicon oxide, and an electron beam heating method was used for aluminum oxide. A low-density linear polyethylene film was dry-laminated on the thus obtained gas barrier film via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

(Comparative Example 2) Vapor deposition was performed on a PET film having a thickness of 12 μm by electron beam heating using aluminum nitride having a purity of 99.9% as a deposition material.
A 30 nm transparent thin film layer was formed. During vapor deposition, a nitrogen gas was flowed, and a 13.56 MHz high frequency power supply (power 300
In W), a plasma was generated. A low-density linear polyethylene film was dry-laminated on the thus obtained gas barrier film via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

Comparative Example 3 A transparent thin film layer having a thickness of 64 nm was formed on a PET film having a thickness of 12 μm by using SiO ₂ having a purity of 99.9% as a deposition material. As the heating method, an electron beam heating method was used. A low-density linear polyethylene film was dry-laminated on the thus obtained gas barrier film via an anchor coat agent in the same manner as in Example 1 to prepare a gas barrier film laminate.

The compositions of the transparent thin films formed in Examples and Comparative Examples were measured, and the oxygen permeability of the gas barrier film and the gas barrier film laminate was measured. The results are shown in Table 1. . Here, the composition of the transparent thin film was measured by X-ray photoelectron spectroscopy (XPS). Further, the oxygen permeability was measured at 40 ° C. and 0% RH using a gas permeability measuring device manufactured by MOCON.

[0045]

[Table 1]

Example 5 The gas barrier film obtained in Example 1 was measured for visible light transmittance for evaluating transparency, and wavelength 390 for evaluating yellowness.
The parallel light transmittance measurement in nm was performed, and the results are shown in Table 2. Note that a spectrophotometer U-3400 manufactured by Hitachi, Ltd. was used as a measuring device, and the light incident surface was on the transparent thin film layer side.

Comparative Example 4 A film on which a silica thin film was formed (a product of Mitsubishi Kojin Pax Co., Ltd., trade name: Tech Barrier) was used as a gas barrier film.
The visible light transmittance and the parallel light transmittance were measured in the same manner as described above, and the results are shown in Table 2.

(Comparative Example 5) The visible light transmittance and the parallel light transmittance of a PET film having a thickness of 12 μm were measured in the same manner as in Example 5, and the results are shown in Table 2.

[0049]

[Table 2]

From the results shown in Table 2, it can be seen that the film used in Example 5 has high transparency and is less yellowish than the film used in Comparative Example 4.

[0051]

Industrial Applicability The gas barrier film and the laminate thereof according to the present invention have high gas barrier properties and excellent transparency, and are used for storage containers of pharmaceuticals that require particularly high gas barrier properties during storage. It is suitable as a material.
Further, according to those production methods, a gas barrier film having high gas barrier properties and excellent transparency and a laminate thereof can be easily produced.

Continued on the front page F-term (reference) 3E086 BA04 BA13 BA15 BB01 CA28 4F100 AA12B AA13B AA19B AA20B AB10B AB11B AK01A AK03A AK03C AK41A AK42 AK45A AK49A AK51G AK63 AK69A02 BA01 BA02 BA03 BA02 BA03 BA02 BA03

Claims (13)

[Claims] An oxygen concentration of 2 to 64 at.% And a nitrogen concentration of 0.5 to 56 on at least one surface of a plastic film.
A transparent thin film layer having an atomic%, a silicon concentration of 0.5 to 55 atomic%, and an aluminum concentration of 5 to 80 atomic% is formed, wherein the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to 100 atomic%. A gas barrier film characterized by the following. 2. The method according to claim 1, wherein the plastic film is a film formed from at least one resin selected from the group consisting of polyester, polyamide, ethylene / vinyl alcohol copolymer, polyolefin, and polyimide. The gas barrier film according to claim 1. 3. The gas barrier film according to claim 1, wherein the gas barrier film is a packaging container for storing a medicine.
Or the gas barrier film according to 2. 4. The gas barrier film laminate according to claim 1, wherein the transparent thin film layer of the gas barrier film according to claim 1 is further covered with a polyolefin film layer. 5. The gas barrier film laminate according to claim 4, wherein the transparent thin film layer and the polyolefin film layer are laminated via an anchor coat agent layer. 6. The gas barrier film laminate according to claim 1, wherein
The gas barrier film laminate according to claim 4, wherein the laminate is a packaging container material for storing a medicine. 7. At least one material selected from the group consisting of aluminum, aluminum oxide and aluminum nitride and at least one material selected from the group consisting of silicon, silicon oxide and silicon nitride on at least one surface of the plastic film The combination with at least one material is used as a deposition material and vacuum-deposited, optionally in the presence of oxygen and / or nitrogen, whereby an oxygen concentration of 2
-64 atomic%, nitrogen concentration 0.5-56 atomic%, silicon concentration 0.5-55 atomic%, and aluminum concentration 5-80
A transparent thin film layer consisting of at.% Is formed, wherein the total concentration of oxygen, nitrogen, silicon and aluminum is 30 to 100.
A method for producing a gas barrier film, characterized in that the content is at least atomic%. 8. The method according to claim 7, wherein the vapor deposition material is a combination of aluminum and silicon. 9. The method according to claim 1, wherein the deposition material comprises aluminum nitride,
The method for producing a gas barrier film according to claim 7, wherein the method is a combination with at least one material selected from the group consisting of silicon, silicon oxide, and silicon nitride. 10. The method for producing a gas barrier film according to claim 7, wherein said vapor deposition material is a combination of aluminum or aluminum oxide and silicon nitride. 11. The gas barrier film according to claim 7, wherein the vacuum deposition is performed under a condition in which a plasma is generated by introducing a nitrogen gas into the system. Production method. 12. The vacuum deposition method according to claim 7, wherein the vacuum deposition is performed under a condition in which nitrogen gas is introduced into the system and nitrogen ions are generated near the surface of the plastic film.
11. The method for producing a gas barrier film according to any one of items 10. 13. A gas comprising the steps of: producing a gas barrier film by the method according to claim 7; and bonding a polyolefin film on the transparent thin film layer via an anchor coat agent. A method for producing a barrier film laminate.