JP6852304B2 - Transparent gas barrier film - Google Patents

Description

The present invention relates to a transparent gas barrier film and a method for producing the same.

The gas barrier film is used, for example, as a packaging material or a sealing material for packaging an article.

For example, packaging materials used for packaging foods, pharmaceuticals, hard disks, semiconductor modules, etc. need to be capable of protecting the contents packaged thereby. In particular, packaging materials used for food packaging need to suppress oxidation and alteration of proteins and fats and oils, and maintain taste and freshness. In addition, packaging materials used for packaging pharmaceutical products that need to be handled in a sterile condition are required to suppress deterioration of the active ingredient and maintain its efficacy. As described above, as a packaging material for protecting the quality of these contents, a gas barrier film having a gas barrier property that blocks oxygen, water vapor, and other gases that alter the contents is required.

In addition, as packaging materials for packaging pharmaceutical products, sealing materials for sealing inkjet tanks, and packaging materials for export such as resins, acceleration tests under high temperature and high humidity, prevention of solvent evaporation at high temperatures, and There is a demand for a gas barrier film exhibiting gas barrier properties suitable for transportation by sea (particularly transportation via the equatorial line), that is, a gas barrier film exhibiting stable and high gas barrier performance even in a harsh environment.

The gas barrier film is also used as a back surface protective sheet for solar cells. The back surface protective sheet for a solar cell is for preventing the patterned silicon thin film, which is a portion of the solar cell module that generates photovoltaic power, from being deteriorated by humidity or the like. The back surface protective sheet for the solar cell is installed on the back surface of the solar cell module main body. As this back surface protective sheet, a gas barrier film that has high barrier performance against gases such as oxygen and water vapor and does not deteriorate the gas barrier performance even when used under harsh conditions such as outdoors, that is, has high durability is required. Be done.

Conventionally, as a packaging material made of plastic, among polymers such as polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), and polyacrylonitrile (PAN), relatively Films made of resins that can achieve high gas barrier performance and multilayer films made by laminating or coating these resins have been preferably used.

However, these resin films are highly temperature-dependent in gas barrier performance, and the gas barrier performance is deteriorated at high temperature or high humidity. Further, when these resin films are applied to food packaging applications, their gas barrier performance is often significantly deteriorated when boiled or retort-treated under high temperature and high pressure conditions. Further, a multilayer film using a PVDC-based resin has a low humidity dependence of gas barrier performance but a high temperature dependence, and ^{can obtain high gas barrier performance (for example, 1 cc / m 2} , day, atm or less). Can not. And PVDC, PAN, etc. have a high risk of generating harmful substances at the time of disposal or incineration.

Therefore, when high gas barrier performance is required, it is necessary to add a metal foil such as aluminum foil to the resin film to ensure the gas barrier performance. However, since the metal foil is opaque, it is difficult to visually confirm the contents of the packaged product packaged with the packaging material containing the metal foil without opening the package. In addition, such packages cannot be inspected by a metal detector or heat-treated in a microwave oven.

In order to solve these problems, many gas barrier films in which an oxide film made of an oxide such as aluminum oxide or silicon oxide is formed as a gas barrier layer on a plastic film have been put into practical use.

Such a gas barrier layer can be formed with high productivity by using a dry coating method, especially a vacuum vapor deposition method. Examples of the dry coating method other than the vacuum vapor deposition method include a sputtering method and a chemical vapor deposition (CVD) method. However, in the sputtering method, although a gas barrier film having excellent gas barrier performance can be obtained, the production speed is significantly slowed down. Further, the CVD method also has a demerit that when it is used for forming a gas barrier layer, the production speed becomes slower than that of the vacuum vapor deposition method.

For the formation of the oxide film using the vacuum vapor deposition method, for example, a metal such as aluminum or a non-metal such as silicon is used as the film forming material, and this film forming material is heated and evaporated in the reaction vessel and also in the reaction vessel. This is performed by introducing a reactive gas such as oxygen into the hair and reacting them to deposit the oxide of the film-forming material on the film. The transparency of the oxide film obtained by this method increases as the collision of the reactive gas with the vaporized particles generated by evaporating the film-forming material increases.

Further, the oxide film formed by the vacuum vapor deposition method can also be formed by using ceramics such as silicon oxide as the film forming material. Also in this method, transparency can be further improved by introducing a reactive gas such as oxygen into the reaction vessel and promoting the above reaction.

The oxide film obtained by such a method is excellent in transparency, but on the other hand, its resistance to physical stress such as stretching is inferior to that of the metal film. Therefore, the gas barrier film containing the oxide film is significantly deteriorated in gas barrier performance by, for example, stretching.

For example, in the formation of a gas barrier layer by a vacuum vapor deposition method, when aluminum is used as a film forming material and a reactive gas such as oxygen is introduced into a reaction vessel, a gas barrier layer made of alumina can be obtained. The gas barrier film provided with this gas barrier layer has excellent transparency and does not interfere with inspection by a metal detector. However, the gas barrier layer made of alumina has very poor resistance to physical stress such as stretching. In addition, alumina is converted to boehmite by hot water treatment such as steam treatment and retort treatment. Therefore, the gas barrier performance of this gas barrier film is significantly deteriorated when, for example, stretching treatment or hot water treatment is performed. If the ratio of oxygen atoms to aluminum atoms is reduced, the gas barrier layer made of alumina approaches the aluminum layer in terms of composition, but the transparency is greatly reduced and physical stress such as stretching is achieved. There is little improvement in resistance to.

Further, the gas barrier film in which the gas barrier layer made of silicon oxide is formed by the vacuum vapor deposition method has excellent transparency and does not interfere with the inspection by the metal detector. And, this gas barrier film does not cause deterioration of gas barrier performance due to boehmite formation of alumina. However, although the gas barrier layer made of silicon oxide is superior to the gas barrier layer made of alumina in resistance to physical stress such as stretching, it is significantly inferior to the gas barrier layer made of aluminum. In a gas barrier film provided with a gas barrier layer made of silicon oxide, if the ratio of oxygen atoms to silicon atoms in the gas barrier layer is reduced, the gas barrier performance is improved, but in addition to the decrease in transparency, physical stretching and the like are performed. Resistance to physical stress also deteriorates.

Regarding the improvement of resistance to physical stress such as stretching of the gas barrier layer, it has been proposed to form a SiOC film by a plasma CVD method (Patent Documents 1 and 2). However, when the plasma CVD method is used, it is necessary to increase the amount of raw materials introduced in order to improve the film formation rate. In that case, the gas barrier performance may be lowered and the transmittance may be lowered.

Further, for the purpose of improving resistance to physical stress such as stretching, it has been proposed to repeat dry coating and wet coating to form a multilayer gas barrier layer. However, if this method is adopted, the productivity will decrease.

Japanese Unexamined Patent Publication No. 2005-219427 Japanese Unexamined Patent Publication No. 2009-190216

An object of the present invention is to make it possible to produce a gas barrier film having excellent resistance to physical stress such as stretching and transparency with high productivity.

According to one aspect of the present invention includes a plastic substrate, a gas barrier layer provided on at least one surface of the plastic substrate, wherein the gas barrier layer is provided on the plastic substrate, denoted by AlO _x is Ri Do a material satisfying and 0 ≦ x ≦ 1.40, a first aluminum-containing layer thickness Ru near the range of 3 to 10 nm, is provided directly on the first aluminum-containing layer, with SiO _y Ri Do from materials meeting inscribed and 1.50 ≦ y ≦ 1.85, thickness and 5 to area by the near of 40nm silicon oxide layer is provided directly on the silicon oxide layer, denoted by AlO _z is Ri Do a material satisfying and 0 ≦ z ≦ 1.40, the film thickness is transparent gas barrier film including a second aluminum-containing layer Ru near the range of 3 to 10nm are provided.

Before SL transparent gas barrier film, the gas barrier further comprising a protective layer provided on the layer, the protective layer is a water-soluble polymer, a metal alkoxide, and at least one selected from the group consisting of reaction products of metal alkoxide It is preferable to include the type.

Further, the transparent gas barrier film further includes a pretreatment layer provided between the plastic base material and the gas barrier layer, and the pretreatment layer is a coat layer or a surface treatment layer based on a resin material. Is preferable.

According to the present invention, it is possible to produce a gas barrier film having excellent resistance to physical stress such as stretching and transparency with high productivity.

A cross-sectional view schematically showing a transparent gas barrier film according to an embodiment of the present invention. FIG. 6 is a diagram schematically showing an apparatus that can be used for manufacturing the transparent gas barrier film of FIG.

FIG. 1 is a cross-sectional view schematically showing a transparent gas barrier film according to an embodiment of the present invention. The transparent gas barrier film 1 shown in FIG. 1 includes a plastic film 10 which is a plastic base material, and a gas barrier layer 11 formed on the plastic film 10.

As the plastic film 10, for example, a known plastic base material for a gas barrier film can be used. Examples of the material of the plastic film 10 include polyimide-based (polyethylene, polypropylene, etc.), polyester-based (polyethylene naphthalate, polyethylene terephthalate, etc.), polyamide-based (nylon-6, nylon-66, etc.), polystyrene, ethylene vinyl alcohol, and the like. Examples thereof include polyvinyl chloride, polyimide, polyvinyl alcohol, polycarbonate, polyether sulfone, acrylic, cellulose type (triacetyl cellulose, diacetyl cellulose, etc.), but are not particularly limited.

It is preferable to use a transparent film as the plastic film 10 from the viewpoint of appearance and the advantage that the contents can be confirmed. The thickness of the plastic film 10 is not particularly limited, but is preferably in the range of 12 to 100 μm in consideration of processability when forming the transparent gas barrier film 1.

The gas barrier layer 11 includes a first aluminum-containing layer 11a, a silicon oxide layer 11b, and a second aluminum-containing layer 11c. The first aluminum-containing layer 11a, the silicon oxide layer 11b, and the second aluminum-containing layer 11c are laminated on the plastic film 10 in this order.

The first aluminum-containing layer 11a is made of a _{material represented by AlO x} and satisfying 0 ≦ x ≦ 1.40. The second aluminum-containing layer 11c is made of a _{material represented by AlO z} and satisfying 0 ≦ z ≦ 1.40. Increasing x and z reduces the resistance of the gas barrier layer 11 to physical stress such as stretching.

The film thickness of each of the first aluminum-containing layer 11a and the second aluminum-containing layer 11c is preferably in the range of 3 to 10 nm in consideration of productivity, gas barrier property, and transmittance. If the film thickness is too small, it is difficult to obtain stable gas barrier performance. Further, if the film thickness is excessively increased, the production speed is slowed down, the cost may be increased, and the transmittance is lowered.

The silicon oxide layer 11b is made of a _{material represented by SiO y} and satisfying 1.50 ≦ y ≦ 1.85. When y is made excessively small, the resistance of the gas barrier layer 11 to physical stress such as stretching is lowered, and the transmittance of the transparent gas barrier film 1 is also lowered. If y is excessively increased, the initial performance regarding the gas barrier performance deteriorates.

The thickness of the silicon oxide layer 11b is preferably in the range of 5 to 40 nm. If the film thickness is too small, it is difficult to obtain stable gas barrier performance. Further, if the film thickness is excessively increased, the production speed is slowed down, the cost may be increased, and the transmittance is lowered.

The transmittance of the gas barrier film 1 is preferably 80% or more, and more preferably 85% or more, in consideration of visibility when used as a packaging material and improvement in appearance. If this transmittance is lowered, transparency cannot be ensured and the appearance is impaired.

As described above, the gas barrier layer 11 of the transparent gas barrier film 1 includes the first aluminum-containing layer 11a, the silicon oxide layer 11b, and the second aluminum-containing layer 11c.

A gas barrier film similar to the transparent gas barrier film 1 except that the silicon oxide layer 11b is omitted is excellent in resistance to physical stress such as stretching. However, such a gas barrier film cannot achieve a high transmittance when the film thickness of the gas barrier layer is increased in order to achieve high gas barrier performance.

Further, the gas barrier film similar to the transparent gas barrier film 1 except that the first aluminum-containing layer 11a and the second aluminum-containing layer 11c are omitted is a case where the film thickness of the gas barrier layer is increased in order to achieve high gas barrier performance. However, high transmittance can be achieved. However, such a gas barrier film has insufficient resistance of the gas barrier layer to physical stress such as stretching.

Further, in the gas barrier film similar to the transparent gas barrier film 1 except that only one of the first aluminum-containing layer 11a and the second aluminum-containing layer 11c is omitted, the film thickness of the gas barrier layer is increased in order to achieve high gas barrier performance. Even in some cases, high transmittance can be achieved. However, such a gas barrier film has insufficient resistance of the gas barrier layer to physical stress such as stretching.

On the other hand, the above-mentioned transparent gas barrier film 1 has excellent resistance of the gas barrier layer 11 to physical stress such as stretching, and the thickness of the first aluminum-containing layer 11a and the second aluminum-containing layer 11c is in the range of 3 to 10 nm. It has excellent transparency by keeping it inside. Further, as will be described later, the transparent gas barrier film 1 can be manufactured with high productivity.

The transparent gas barrier film 1 can be deformed in various ways.
For example, in the transparent gas barrier film 1 of FIG. 1, the gas barrier layer 11 is provided only on one surface of the plastic film 10, but the gas barrier layer 11 may be provided on both sides of the plastic film 10.

Further, a pretreatment layer may be provided between the plastic film 10 and the gas barrier layer 11 for the purpose of further improving the gas barrier performance and the adhesion. The pretreatment layer is a coating based on a resin material. A layer, that is, an anchor coat layer may be provided. Alternatively, prior to forming the gas barrier layer 11 as the pretreatment layer, the surface of the plastic film 10 is subjected to physical treatment such as (1) plasma treatment, corona treatment, and frame treatment, and (2) acid. Alternatively, the surface treatment layer may be formed by performing a surface treatment such as a chemical treatment such as a chemical treatment with an alkali.

Further, a protective layer or the like may be provided on the gas barrier layer 11. The protective layer preferably contains at least one selected from the group consisting of water-soluble polymers, metal alkoxides, and reaction products of metal alkoxides. Above all, it is desirable to provide a coating film containing a metal alkoxide as the protective layer. Further, a nylon film, a polypropylene film or the like may be laminated on the nylon film or polypropylene film. The "reaction product of metal alkoxide" means a hydrolysis product of metal alkoxide, a polycondensation product thereof, or both of them.

As the metal alkoxide, specifically, ^one _{represented by the general formula R 1 mM} (OR ² ) _n can be used. Here, R ¹ and R ² are organic groups having 1 to 8 carbon atoms, M is a metal atom, and m and n are natural numbers. Examples of the metal atom include Si, Ti, Al, Zr and the like.

^{R 1} _m Si (OR ² ) _{n in} which the metal atom M is Si includes tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, and Examples thereof include dimethyldiethoxysilane.

^{Examples of R 1} _m Zr (OR ² ) _{n in} which the metal atom M is Zr include tetramethoxyzirconium, tetraethoxyzaldehyde, tetraisopropoxyzurizer, and tetraptoxyzurizer.

^{Examples of R 1} _m Ti (OR ² ) _{n in} which the metal atom M is Ti include tetramethoxytitanium, tetraethoxytitanium, tetraisopropoxytitanium, and tetrabutoxytitanium.

^{Examples of R 1} _m Al (OR ² ) _{n in} which the metal atom M is Al include tetramethoxyaluminum, tetraethoxyaluminum, tetraisopropoxyaluminum, and tetrabutoxyaluminum.

The above metal alkoxide may be used alone or in combination of two or more. Further, the reaction product thereof may be used in place of the metal alkoxide or in addition to the metal alkoxide.

One or more of acrylic acid, polyvinyl alcohol, urethane compound, and polyester compound may be mixed with the metal alkoxide and / or the reaction product thereof. In particular, it is desirable to mix with a swellable material.

When performing lamination, it is preferable to use a urethane-based adhesive as the adhesive. The lamination is preferably performed by, for example, a dry lamination method, a non-solvent lamination method, an extrusion lamination method, or a knee ram lamination method.

Next, a method for producing the transparent gas barrier film 1 will be described with reference to FIGS. 1 and 2.
FIG. 2 is a diagram schematically showing an apparatus that can be used for manufacturing the transparent gas barrier film shown in FIG. The manufacturing apparatus 2 shown in FIG. 2 is a vacuum vapor deposition apparatus. The manufacturing apparatus 2 evaporates the vacuum chamber 20, the unwinding roller 21, the guide roller 22, the film forming rolls 23a to 23c, the winding roller 24, the container 25a to 25c, the vapor deposition material 26a to 26c, and the vapor deposition material 26a to 26c. It includes sources 27a-27c and a vacuum pump (not shown).

The vacuum chamber 20 is a reaction vessel for forming the gas barrier layer shown in FIG. The vacuum chamber 20 is connected to a vacuum pump.
The internal space of the vacuum chamber 20 is vertically partitioned by a partition plate 20a. The partition plate 20a is provided with three openings.

The unwinding roller 21, the guide roller 22, and the winding roller 24 are installed in the area above the partition plate 20a in the internal space of the vacuum chamber 20. Further, the film forming rolls 23a to 23c are installed in the region above the partition plate 20a in the internal space of the vacuum chamber 20 so that they partially protrude below the partition plate 20a at the position of the opening. There is.

The containers 25a to 25c are respectively installed in the area below the partition plate 20a in the internal space of the vacuum chamber 20. The containers 25a to 25c contain the vapor deposition materials 26a to 26c, respectively. The vapor deposition materials 26a and 26c are made of, for example, aluminum. The thin-film deposition material 26b is made of, for example, silicon oxide.

The evaporation sources 27a to 27c are, for example, straight-ahead electron beam guns. The evaporation sources 27a to 27c evaporate or sublimate the vapor deposition materials 26a to 26c, respectively.

The transparent gas barrier film 1 is manufactured by using the manufacturing apparatus 2 by, for example, the following method.
First, the vacuum pump is operated to evacuate the internal space of the vacuum chamber 20.

Next, the plastic film 10 is unwound from the unwinding roller 21, guided by the guide roller 22 to the film forming rolls 23a to 23c and the winding roller 24, and wound on the winding roller 24.

On the other hand, the evaporation sources 27a and 27c are operated to evaporate or sublimate the vaporized materials 26a to 26c. In FIG. 2, reference numerals 28a to 28c indicate electron beams emitted from the evaporation sources 27a and 27c, respectively. Reference numerals 29a to 29c indicate vapors of the vapor-deposited materials 26a to 26c, respectively.

The steams 29a to 29c diffuse upward from the containers 25a to 25c, respectively, and come into contact with the plastic film 10 on the film forming rolls 23a to 23c at the position of the opening. Then, the plastic film 10 passes on the film forming rolls 23a to 23c in this order. As a result, aluminum, silicon oxide, and aluminum are deposited on the plastic film 10 in this order. In this way, the plastic film 10 shown in FIG. 1 is obtained.

When the first aluminum-containing layer 11a and the second aluminum-containing layer 11c are formed, an oxidation gas such as oxygen is not introduced, but a residual gas such as water is present in the formation space. Since oxidation by this residual gas occurs, the first aluminum-containing layer 11a and the second aluminum-containing layer 11c contain an oxygen component.

The manufacturing method described with reference to FIG. 2 can be modified in various ways.
For example, in the manufacturing apparatus 2 of FIG. 2, a straight-moving electron beam gun is used as the evaporation source 27a to 27c, but a deflecting electron beam gun may be used as the evaporation source 27a to 27c, and a high film forming speed is achieved. In order to develop it, a Pierce type flat cathode type electron gun capable of inputting a large amount of power may be used.

Further, the vapor deposition method is not limited to the electron beam vapor deposition method, and the vapor deposition materials 26a and 26c may be heated by using a resistance heating method, a high frequency induction heating method, or the like to cause evaporation or sublimation of the materials. The resistance heating method may be a method in which the pit filled with the vapor deposition material is directly resistance-heated, or when the first aluminum-containing layer 11a and the second aluminum-containing layer 11c are formed, the resistance heating portion is made of aluminum. It may be a resistance heating method of a type that feeds a wire. Regardless of which method is adopted, it is desirable that the structure is such that a high film forming rate can be exhibited.

When forming the gas barrier layer 11, oxygen or an organic silane-based monomer may be introduced into the vacuum chamber 20. Higher permeability can be achieved by depositing silicon oxide in the presence of oxygen or organic silane-based monomers. In particular, when silicon oxide is deposited in the presence of an organic silane-based monomer, the effects of improving the transmittance and improving the resistance to physical stress such as stretching are further enhanced.

However, when such a reactive gas is introduced, the pressure in the vacuum chamber 20 increases, and as a result, the mean free path of the vaporized particles resulting from the evaporation of the vaporized material is shortened. Therefore, the number of collisions of the vapor-deposited particles increases, much of the kinetic energy of the vapor-deposited particles is lost, and the gas barrier performance may deteriorate.

As a countermeasure, it is effective to newly apply kinetic energy to the vapor-deposited particles in order to compensate for the lost kinetic energy. Of these, a method using plasma, particularly a method capable of achieving a high plasma density, is preferable. As a method for generating plasma at a high density, for example, any one of an inductively coupled plasma (ICP) method, a helicon wave plasma method, a microwave plasma method, and a hollow cathode discharge method can be used.

When forming a film at a high film forming rate, the number of deposited particles is very large. Therefore, when plasma cannot be generated at a high density, the number of plasma-generated particles is smaller than that of the vapor-deposited particles, and it is difficult to sufficiently compensate for the lost kinetic energy.

When plasma is generated at a high density, the lost kinetic energy can be sufficiently compensated, and therefore, even if film formation is performed at a high film formation rate, deterioration of gas barrier performance can be sufficiently suppressed. The gas barrier performance can be further improved. Further, in this case, the reaction between the vapor-deposited particles and the reactive gas can be promoted.

Aluminum deposition is carried out in an atmosphere that is substantially free of oxygen. That is, the evaporation and deposition of aluminum for forming the first aluminum-containing layer 11a and the second aluminum-containing layer 11c is performed in an atmosphere substantially free of oxygen. When aluminum is vapor-deposited in an atmosphere containing a high concentration of oxygen, an alumina layer is formed. This alumina layer has excellent transmittance, but has very poor resistance to physical stress such as stretching. When aluminum is vapor-deposited in an atmosphere that does not substantially contain oxygen, an aluminum-containing layer having excellent resistance to physical stress of stretching can be obtained.
In the "atmosphere that does not substantially contain oxygen", oxygen is not supplied to the region between the film forming roll 23a and the vapor deposition material 26a or the region between the film forming roll 23c and the vapor deposition material 26c. , The atmosphere in those regions when the inside of the vacuum chamber 20 is evacuated. The description "atmosphere substantially free of oxygen" does not preclude the oxygen-containing compounds remaining in the vacuum chamber 20 from being mixed into the atmosphere in the region.

The gas barrier film manufacturing apparatus is not limited to the structure shown in FIG. For example, the arrangement of rolls and the like may be changed. Further, a plasma processing device or a reactive gas introduction device may be installed. Examples of the method of introducing the reactive gas into the vacuum chamber 20 include a method of installing a pipe or the like and supplying the reactive gas to the vapor of the vapor-deposited material through the pipe or the like. For example, when depositing silicon oxide in the presence of oxygen or an organic silane-based monomer, the pipe is installed so that one end thereof faces the region between the film forming roll 23b and the vapor deposition material 26b shown in FIG. Then, the reactive gas may be supplied to the other end.

(Example 1)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.40) represented by _{AlO x} on one side of a polyethylene terephthalate film (P60 manufactured by Toray Industries, Inc.) having a thickness of 12 μm. A silicon oxide layer made of a material represented by _{SiO y} (y = 1.85) and a second aluminum-containing layer made of a material represented by _{AlO z (z = 1.40) were formed in this order.}
When the first and second aluminum-containing layers were formed, aluminum was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced. Further, when the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.65 was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced.
As described above, a transparent gas barrier film was produced.

(Example 2)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.40) represented by _{AlO x} on one side of a 12 μm-thick polyethylene terephthalate film (P60 manufactured by Toray Corporation). A silicon oxide layer made of a material (y = 1.50) represented by _{SiO y} and a second aluminum-containing layer made of a material (z = 1.40) represented by _{AlO z were formed in this order.}
When the first and second aluminum-containing layers were formed, aluminum was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced. Further, when the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.40 was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced.
As described above, a transparent gas barrier film was produced.

(Example 3)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.40) represented by _{AlO x} on one side of a polyethylene terephthalate film (P60 manufactured by Toray Industries, Inc.) having a thickness of 12 μm. A silicon oxide layer made of a material represented by _{SiO y} (y = 1.70) and a second aluminum-containing layer made of a material represented by _{AlO z (z = 1.40) were formed in this order.}
When the first and second aluminum-containing layers were formed, aluminum was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced. Further, when the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.61 was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced.
As described above, a transparent gas barrier film was produced.

(Comparative Example 1)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.40) represented by _{AlO x} on one side of a 12 μm-thick polyethylene terephthalate film (P60 manufactured by Toray Corporation). A silicon oxide layer made of a material (y = 2.00) represented by _{SiO y} and a second aluminum-containing layer made of a material (z = 1.40) represented by _{AlO z were formed in this order.}
When the first and second aluminum-containing layers were formed, aluminum was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced. When the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.65 was used as a material for vapor deposition, and oxygen gas was introduced.
As described above, a transparent gas barrier film was produced.

(Comparative Example 2)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.40) represented by _{AlO x} on one side of a polyethylene terephthalate film (P60 manufactured by Toray Industries, Inc.) having a thickness of 12 μm. A silicon oxide layer made of a material represented by _{SiO y} (y = 1.30) and a second aluminum-containing layer made of a material represented by _{AlO z (z = 1.40) were formed in this order.}
When the first and second aluminum-containing layers were formed, aluminum was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced. Further, when the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.20 was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced.
As described above, a transparent gas barrier film was produced.

(Comparative Example 3)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.50) represented by _{AlO x} on one side of a polyethylene terephthalate film (P60 manufactured by Toray Industries, Inc.) having a thickness of 12 μm. A silicon oxide layer made of a material represented by _{SiO y} (y = 1.70) and a second aluminum-containing layer made of a material represented by _{AlO z (z = 1.50) were formed in this order.}
When forming the first and second aluminum-containing layers, aluminum was used as a material for vapor deposition, and oxygen gas was introduced. Further, when the silicon oxide layer was formed, silicon oxide having an atomic ratio of oxygen to silicon of 1.61 was used as a material for vapor deposition, and a reactive gas such as oxygen gas was not introduced.
As described above, a transparent gas barrier film was produced.

(Comparative Example 4)
Using the manufacturing apparatus 2 of FIG. 2, a first aluminum-containing layer made of a material (x = 1.50) represented by _{AlO x} on one side of a 12 μm-thick polyethylene terephthalate film (P60 manufactured by Toray Corporation). A silicon oxide layer made of a material (y = 2.00) represented by _{SiO y} and a second aluminum-containing layer made of a material (z = 1.50) represented by _{AlO z were formed in this order.}
When forming the first and second aluminum-containing layers, aluminum was used as a material for vapor deposition, and oxygen gas was introduced. When the silicon oxide layer was formed, oxygen gas was introduced using silicon oxide having an atomic ratio of oxygen to silicon of 1.85 as a material for vapor deposition.
As described above, a transparent gas barrier film was produced.

(Evaluation 1)
The water vapor transmittance (WVTR) of the transparent gas barrier film according to Examples 1 to 3 and Comparative Examples 1 to 4 was measured at 40 ° C. and 90% RH atmosphere by a water vapor permeability measuring device (MOCON PERMATRAN 3/21 manufactured by Mocon Co., Ltd.). Measured under conditions. The results are shown in Table 1.
Further, each of the transparent gas barrier films according to Examples 1 to 3 and Comparative Examples 1 to 3 was cut into fragments having a length of 20 cm. Then, both ends of each fragment were held and a tension of 11.8 N was applied to the fragments, which were stretched at a rate of 100 μm / sec until the stretch ratio reached 5%. Then, the WVTR of each fragment was measured. The results are shown in Table 1.

(Evaluation 2)
The transmittance of the transparent gas barrier films according to Examples 1 to 3 and Comparative Examples 1 to 4 was measured with a spectrophotometer (UV-2450 manufactured by SHIMADZU) with the baseline as the atmosphere. The results are shown in Table 1. The transmittance of the polyethylene terephthalate film (P60 manufactured by Toray Industries, Inc.) having a thickness of 12 μm was 85.9% T.

(Evaluation 3)
The compositions of the first and second aluminum-containing layers and the silicon oxide layer contained in the transparent gas barrier films according to Examples 1 to 3 and Comparative Examples 1 to 4 were measured by a photoelectron spectrometer (JPS-9010MX manufactured by JEOL Ltd.). .. The results are shown in Table 1.

(Evaluation result 1)
As shown in Table 1, the transparent gas barrier films according to Examples 1 to 3 had little deterioration in gas barrier performance due to stretching. In particular, the transparent gas barrier film according to Example 1 had the least deterioration in gas barrier performance due to stretching.
The transparent gas barrier film according to Comparative Example 1 had little deterioration in gas barrier performance after stretching, but was inferior in gas barrier performance before stretching. Further, the transparent gas barrier films according to Comparative Examples 2 to 4 were excellent in gas barrier performance before stretching, but the deterioration of gas barrier performance due to stretching was large.

(Evaluation result 2)
As shown in Table 1, the transparent gas barrier films according to Examples 1 to 3 and Comparative Examples 1, 3 and 4 had a transmittance of 80% or more. On the other hand, the transparent gas barrier film according to Comparative Example 2 had a low permeability.

The transparent gas barrier film of the present invention can be used, for example, as a packaging material for packaging foods, beverages, pharmaceuticals or other articles. In this case, the transparent gas barrier film can be used in various forms such as bags, lids, and packing films. Alternatively, the transparent gas barrier film of the present invention can also be used as a sealing material for an inkjet tank sealing film and a solar cell back sheet.
The inventions described in the original claims are added below.
[1]
A plastic base material and a gas barrier layer provided on at least one surface of the plastic base material are provided.
The gas barrier layer is
A first aluminum-containing layer provided on the plastic substrate and made of a material _{represented by AlO x} and satisfying x ≦ 1.40.
A silicon oxide layer provided on the first aluminum-containing layer _{and made of a material represented by SiO y} and satisfying 1.50 ≦ y ≦ 1.85.
A second aluminum-containing layer provided on the silicon oxide layer and made of a material represented by _{AlO z and satisfying z ≦ 1.40.}
Transparent gas barrier film containing.
[2]
Item 2. The transparent gas barrier film according to Item 1, wherein the first and second aluminum-containing layers have a film thickness in the range of 3 to 10 nm, and the silicon oxide layer has a film thickness in the range of 5 to 40 nm.
[3]
Item 1 or 2 further comprising a protective layer provided on the gas barrier layer, wherein the protective layer contains at least one selected from the group consisting of a water-soluble polymer, a metal alkoxide, and a reaction product of the metal alkoxide. The transparent gas barrier film described in.
[4]
A pretreatment layer provided between the plastic base material and the gas barrier layer is further provided, and the pretreatment layer is any one of Items 1 to 3 which is a coating layer or a surface treatment layer based on a resin material. The transparent gas barrier film described in the section.
[5]
Evaporation and deposition of aluminum, sublimation and deposition of silicon oxide, evaporation and deposition of aluminum by any method selected from the group consisting of electron beam deposition method, resistance heating method and high frequency induction heating method in vacuum. In this order, a gas barrier layer containing the first aluminum-containing layer, the silicon oxide layer, and the second aluminum-containing layer is formed on at least one surface of the plastic base material. A method for producing a transparent gas barrier film, wherein the evaporation and deposition of aluminum for forming the second aluminum-containing layer is carried out in an atmosphere substantially free of oxygen.
[6]
When forming the gas barrier layer, any method selected from the group consisting of the electron beam vapor deposition method, the resistance heating method and the high frequency induction heating method, an induction coupling plasma method, a helicon wave plasma method, and a microwave. Item 5. The method for producing a transparent gas barrier film according to Item 5, wherein any method selected from the group consisting of a plasma method and a holocathode discharge method is used in combination.
[7]
Item 5. The method for producing a transparent gas barrier film according to Item 5 or 6, wherein when the gas barrier layer is formed, an organic silane-based monomer is introduced into a reaction vessel for forming the gas barrier layer.

1 ... Transparent gas barrier film, 2 ... Manufacturing equipment, 10 ... Plastic film, 11 ... Gas barrier layer, 11a ... First aluminum-containing layer, 11b ... Silicon oxide layer, 11c ... Second aluminum-containing layer, 20 ... Vacuum chamber, 20a ... Partition plate, 21 ... unwinding roller, 22 ... guide roller, 23a ... film forming roll, 23b ... film forming roll, 23c ... film forming roll, 24 ... winding roller, 25a ... container, 25b ... container, 25c ... container, 26a ... Evaporated material, 26b ... Evaporated material, 26c ... Evaporated material, 27a ... Evaporation source, 27b ... Evaporation source, 27c ... Evaporation source, 28a ... Electron beam, 28b ... Electron beam, 28c ... Electron beam, 29a ... Steam, 29b ... steam, 29c ... steam.

Claims (3)

A plastic base material and a gas barrier layer provided on at least one surface of the plastic base material are provided.
The gas barrier layer is
Provided on the plastic substrate, Ri Do from materials meeting is and x ≦ 1.40 notation AlO _x, a first aluminum-containing layer Ru near the range of thickness of 3 to 10 nm,
Directly provided on the first aluminum-containing layer, Ri Do from materials meeting by and 1.50 ≦ y ≦ 1.85 denoted by SiO _y, and the thickness is 5 to area by the near of 40nm silicon oxide layer ,
Wherein provided directly on the silicon oxide layer, Ri Do from materials meeting is and z ≦ 1.40 notation AlO _z, transparent including a second aluminum-containing layer thickness Ru near the range of 3 to 10nm Gas barrier film. The first aspect of claim 1, further comprising a protective layer provided on the gas barrier layer, wherein the protective layer comprises at least one selected from the group consisting of a water-soluble polymer, a metal alkoxide, and a reaction product of the metal alkoxide. The transparent gas barrier film described. The first or second claim, further comprising a pretreatment layer provided between the plastic base material and the gas barrier layer, wherein the pretreatment layer is a coating layer or a surface treatment layer based on a resin material. Transparent gas barrier film.

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