JP2000233476A - Transparent barrier film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give an excellent transparency and excellent gas barrier properties against oxygen, water vapor or the like to this film by a method wherein a vapor deposited film made of inorganic oxide is formed on the surface layer plane of a multilayered polypropylene film, at least the surface layer of which is made of a low melting polypropylene resin layer. SOLUTION: A transparent barrier film 1 is produced by providing a vapor deposited film made of inorganic oxide on the surface layer plane of a multilayered polypropylene film 3, at least the surface layer of which is made of a low melting polypropylene resin layer 2. In this case, the multilayered polypropylene film 3 is formed by a plurality of polypropylene resin layers, the melting points of which become higher in succession from its surface layer to its inner layer. The vapor deposited film 4 of the inorganic oxide is produced by means of a vacuum deposited method, a plasma chemical vapor phase growth method or the like. Thus, a film, which is excellent in transparency as an enough flexibility, and is excellent in oxygen gas barrier properties, water vapor gas barrier properties or the like can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a transparent barrier film, and more particularly, to a transparent barrier film having excellent transparency and excellent gas barrier properties against oxygen gas, water vapor and the like.

[0002]

2. Description of the Related Art Conventionally, various packaging materials having excellent oxygen gas barrier properties and water vapor barrier properties have been developed and proposed. One of them has recently been a substrate such as a plastic film. On one side of the film, using physical vapor deposition, or chemical vapor deposition, etc.,
For example, a deposition film provided with a deposition film of an inorganic oxide such as silicon oxide or aluminum oxide has been proposed. This material is excellent in oxygen gas barrier properties, water vapor barrier properties, etc., and has transparency, and is attracting attention as a packaging material suitable for environmental protection. In recent years, other plastic films, or paper base materials etc. It is laminated with packaging materials and is suitable for filling and packaging of various articles such as foods and drinks, pharmaceuticals, cosmetics, detergents, and the like, and is expected to expand its demand.

[0003]

However, in the above-described vapor-deposited film, the oxygen gas barrier property and the water vapor barrier property are certainly improved, but this is because all kinds of base films such as plastic films are used. It is not something that fits. For example, a biaxially oriented polypropylene film is used as a base film such as a plastic film, and on one surface thereof, using a physical vapor deposition method, for example, a deposited film of an inorganic oxide such as silicon oxide or aluminum oxide. When the is provided, the biaxially stretched polypropylene film as the base film is deteriorated or shrunk due to the influence of heating at the time of vapor deposition because the heat resistance is inferior to the biaxially stretched polypropylene film as the base film. However, it becomes extremely difficult to form a desirable vapor-deposited film thereon, and as a result, it is not expected to improve oxygen gas barrier properties and the like. For this reason,
When a biaxially stretched polypropylene film is used as the base film, by using a plasma chemical vapor deposition (CVD) method, which can perform a vapor deposition process at a relatively low temperature,
It has been proposed to produce a vapor deposition film provided with a vapor deposition film of an inorganic oxide such as silicon oxide, thereby making it possible to produce a vapor deposition film having improved oxygen gas barrier properties and the like. However, the above-mentioned plasma chemical vapor deposition (CV)
D)), but often
It is easy to produce a yellowed deposited film or the like, and the cause is that the biaxially stretched polypropylene film itself turns yellow due to the action of plasma, or turns yellow due to coloring of the deposited film. It is estimated that Generally, the biaxially stretched polypropylene film itself has a very poor oxygen gas barrier property (about 1000 c).
c / m ² / day or more). Therefore, in a vapor-deposited film in which a vapor-deposited film of an inorganic oxide such as silicon oxide is provided on a biaxially stretched polypropylene film, the oxygen gas barrier property and the like are in a film quality state. For example, if there is a slight defect in the deposited film, the oxygen gas barrier property is remarkably reduced, and a sufficient oxygen gas barrier property cannot be expected. For example, a biaxially stretched polyethylene terephthalate film or a nylon film is used as a base film, and a vapor-deposited film provided with a vapor-deposited film of an inorganic oxide such as silicon oxide using a plasma chemical vapor deposition method. Even if a vapor-deposited film provided with a vapor-deposited film of an inorganic oxide such as silicon oxide is produced by applying the optimal production conditions for producing Since the stretched polypropylene film itself is very poor in oxygen gas barrier properties, it is extremely difficult to produce a vapor-deposited film having sufficient oxygen gas barrier properties even after forming a vapor-deposited thin film. For this reason, when forming a vapor deposition film of an inorganic oxide such as silicon oxide on one surface of a biaxially stretched polypropylene film using a plasma chemical vapor deposition method (CVD method), for example, the line speed is slightly reduced. Consider the deposition conditions such as increasing the content of the monomer gas for vapor deposition in the gas mixture composition for vapor deposition, or increasing the power of the electric power supplied to the cooling / electrode drum, and forming the vapor deposition film. However, in such a case, there is a problem that the thickness of the deposited film tends to be increased, and as a result, it is difficult to form a deposited film having high bending resistance. Further, as described above, when the vapor deposition film is formed by increasing the power of the electric power supplied to the cooling / electrode drum, the biaxially stretched polypropylene film itself as the base film itself becomes yellow due to the plasma irradiation during the vapor deposition. Phenomena such as change or deterioration.
A considerable impact is given to the axially stretched polypropylene film itself. For example, in the layer of the biaxially stretched polypropylene film itself, its lamellar structure is destroyed, its strength and the like are deteriorated, and therefore, other resin films are laminated. Even when manufacturing a laminated material as a packaging material, a cohesive failure or the like occurs from a portion where the strength is deteriorated, delamination occurs at that portion, and a packaging container or the like is manufactured using the above-described vapor-deposited film. However, there is a problem that it is difficult to manufacture a useful packaging container or the like having excellent oxygen gas barrier properties and water vapor barrier properties. Further, the biaxially stretched polypropylene film has a very inert surface, is inferior in surface wettability, and can be processed at a relatively low temperature using a plasma-enhanced chemical vapor deposition (CVD) method. Even if a vapor-deposited film of an inorganic oxide is formed, the adhesion to the vapor-deposited film is poor, and as a result, there is a problem that a sufficiently satisfactory oxygen gas barrier property or the like cannot be obtained. Therefore, the present invention
Using a biaxially oriented polypropylene film as the base film, using a chemical vapor deposition method such as plasma, no destruction of the lamellar structure in the film layer, etc., was observed, and it had excellent transparency and oxygen gas, water vapor, etc. An object of the present invention is to provide a transparent barrier film having excellent gas barrier properties.

[0004]

As a result of various studies to solve the above problems, the present inventor has used a biaxially oriented polypropylene film as a base film, and When forming a deposited thin film of an inorganic oxide such as silicon oxide on one surface using a plasma-enhanced chemical vapor deposition method or the like, at least paying attention to using a multilayer polypropylene film having a surface layer made of a low-melting polypropylene resin layer. Then, on the surface of the multilayer polypropylene film, a transparent barrier film was produced by providing an inorganic oxide deposited film such as silicon oxide using a plasma chemical vapor deposition method or the like. Does not show the destruction of the lamella structure by plasma irradiation, deterioration of its strength, etc., and also prevents its yellowing, etc. In addition, excellent transparency, and excellent in flexibility, and also can form a vapor-deposited thin film of an inorganic oxide such as silicon oxide excellent in oxygen gas barrier properties, water vapor barrier properties, etc., other resin films, Alternatively, laminated with a packaging material such as a paper base, for example, food and drink, pharmaceuticals, cosmetics,
The present invention has been completed by finding that a transparent barrier film useful for producing a packaging container or the like suitable for filling and packaging of various articles such as detergents and the like can be produced.

That is, the present invention relates to a transparent barrier film characterized in that at least the surface layer is provided with a vapor-deposited inorganic oxide film on the surface of a multilayer polypropylene film comprising a low melting point polypropylene resin layer. is there.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the drawings. First, FIG. 1 is a schematic sectional view showing a layer configuration of an example of the transparent barrier film according to the present invention. As shown in FIG. 1, the transparent barrier film 1 according to the present invention has, as shown in FIG. That is the basic configuration.

In the above-mentioned transparent barrier film according to the present invention, at least the surface layer of the multilayer polypropylene film composed of a low-melting polypropylene resin layer will be described in more detail. First, as the low-melting polypropylene resin layer constituting the multilayer polypropylene film, Is
A layer composed of a polypropylene resin layer containing a low-melting polypropylene resin or a polypropylene resin layer composed of only a low-melting polypropylene resin can be used. Specifically, in the present invention, as shown in FIG. 2, the multilayer polypropylene film has a melting point of at least 2 which gradually increases from the surface layer toward the inner layer.
Layers or more of polypropylene resin layers 11, 12,..., 00
What consists of the multilayer polypropylene film A consisting of these can be used. In the present invention, examples of the multilayer polypropylene film include, for example, a homopolymer of propylene or a copolymer of propylene and ethylene, another monomer such as an α-olefin such as butene-1, and the like, and One or two or more blends of a polypropylene resin having a melting point in the range of about 150 ° C. to 170 ° C. are used, and the melting points thereof are gradually increased from the surface layer toward the inner layer. A multi-layer polypropylene resin produced by molding into two or more layers using, for example, a T-die co-extrusion method, a co-inflation method, or a coating method. Film or sheet can be used. In the present invention, as the multilayer polypropylene film, for example, a conventional stretching method such as a tenter method or a tube method is used.
Axial or biaxially stretched uniaxial or 2
An axially stretched multi-layer polypropylene film can be used. In the present invention, the thickness of the multilayer stretched polypropylene film can be appropriately set in consideration of the stability at the time of producing the film or sheet, but is preferably about 10 to 100 μm, preferably about 10 to 100 μm. , 15-50
μm is desirable. In the present invention, the above-mentioned multilayer polypropylene film may be provided with a primer in advance on its surface, if necessary, in order to increase its heat resistance and adhesion to a deposited film of an inorganic oxide such as silicon oxide. Co
Agent layer or the like can also be provided. The surface of the above-mentioned multilayer polypropylene film can be optionally subjected to a surface activation treatment such as a corona treatment, a plasma treatment, a framing treatment and the like, if necessary. Furthermore, in the present invention, depending on the application, for example, an antistatic agent,
A desired additive such as an ultraviolet absorber, a plasticizer, a lubricant, a filler, and the like may be arbitrarily added within a range that does not affect the transparency, and a multilayer polypropylene film containing the additive may be used.

Further, in the present invention, as shown in FIG. 3, at least the surface layer of the multilayer polypropylene film is constituted by a low melting point polypropylene resin layer 11, and a barrier resin is used as an intermediate layer. A polypropylene resin layer composed of a barrier resin layer 11a and further using a polypropylene resin having a higher melting point than the above-mentioned surface layer, between the surface layer and the intermediate layer, and / or below the intermediate layer. Alternatively, a multilayer polypropylene film A ₁ formed by arbitrarily laminating two or more layers 12,... 00
Can be used. Thus, as the multilayer polypropylene film, for example, as described above, a propylene homopolymer, or propylene and ethylene,
It is composed of a copolymer with another monomer such as an α-olefin such as butene-1 and has a melting point of 150 ° C. to 170 ° C.
Or 2 types of polypropylene resin within the range of
More than one kind of blends are used, and these are combined so that the melting point thereof is gradually increased from the surface layer toward the inner layer, and further, the barrier resin constituting the intermediate layer is combined, for example, co-extrusion with a T-die. , A co-inflation method, a coating method, or the like, and a multilayer polypropylene resin film or sheet having a barrier resin layer in the intermediate layer. In the above, as the barrier resin, oxygen gas,
A resin having a barrier property against water vapor and the like, and which can be coextruded with a polypropylene resin, for example, ethylene-
Saponified vinyl acetate copolymer, vinyl alcohol-based resin, polyacrylonitrile-based resin, polyamide-based resin,
Polyester resins, polyvinylidene chloride resins, and others can be used. Of course, in the present invention,
In the same manner as described above, the multi-layer polypropylene film may be uniaxially or biaxially stretched using a normal stretching method such as a tenter method or a tube method. Axial or biaxially oriented multilayer polypropylene films can be used. In the present invention, the thickness of the above-mentioned multilayer stretched polypropylene film can be appropriately set in consideration of the stability during the production of the film or sheet.
It is desirably about 0 μm, preferably about 15 to 50 μm.
In the present invention, as the above-mentioned multilayer polypropylene film, as necessary, in order to improve the heat resistance and adhesion with a deposited film of an inorganic oxide such as silicon oxide,
A primer coating agent layer or the like may be provided on the surface in advance. The surface of the above-mentioned multilayer polypropylene film can be optionally subjected to a surface activation treatment such as a corona treatment, a plasma treatment, a framing treatment and the like, if necessary. Furthermore, in the present invention, depending on the application, for example, an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant, a filler, and other additives as desired, within a range that does not affect the transparency thereof. In addition, a multilayer polypropylene film or the like containing them can be used.

Next, in the transparent barrier film according to the present invention, the vapor-deposited film of an inorganic oxide will be described in more detail. First, as the vapor-deposited film of an inorganic oxide, a metal oxide is basically used. Any amorphous thin film can be used. For example, silicon (S
i), aluminum (Al), magnesium (Mg),
Calcium (Ca), potassium (K), tin (Sn),
Sodium (Na), boron (B), titanium (Ti),
A thin film in which an oxide of a metal such as lead (Pb), zirconium (Zr), or yttrium (Y) is made amorphous can be used. Thus, as a material suitable for a packaging material or the like, a thin film in which an oxide of a metal such as silicon (Si) or aluminum (Al) is made amorphous can be given. Thus, a thin film in which the above metal oxide is made amorphous can be referred to as a metal oxide such as silicon oxide, aluminum oxide, and magnesium oxide. For example, MO _X such as SiO _X , AlO _X , MgO _X, etc.
(However, in the formula, M represents a metal element, and the value of X varies depending on the metal element.) The range of the value of X is silicon (Si).
Is 0 to 2, aluminum (Al) is 0 to 1.5, magnesium (Mg) is 0 to 1, calcium (Ca)
Is 0 to 1, potassium (K) is 0 to 0.5, tin (S
n) is 0 to 2, sodium (Na) is 0 to 0.5,
Boron (B) is from 0 to 1, 5 and titanium (Ti) is from 0 to
2. Lead (Pb) is 0 to 1 and zirconium (Zr) is 0.
~ 2, yttrium (Y) can take values in the range of 0-1.5. In the above, when X = 0, it is a perfect metal, it is not transparent and cannot be used at all, and the upper limit of the range of X is a completely oxidized value. In the present invention, as the packaging material, generally,
Examples other than silicon (Si) and aluminum (Al) are rarely used. Silicon (Si) has a value in the range of 1.0 to 2.0, and aluminum (Al) has a value in the range of 0.5 to 1.5. Can be used. In the present invention, the thickness of the inorganic oxide thin film as described above, depending on the type of metal used, or metal oxide, etc., for example,
About 50-3000Å, preferably 100-1000Å
It is desirable to arbitrarily select and form within the range of the order.
Further, in the present invention, the inorganic oxide deposited film is not limited to one layer of the inorganic oxide thin film, but may be in the form of a laminate in which two or more layers are stacked. As the metal oxide, one type or a mixture of two or more types may be used to form a vapor deposited film of an inorganic oxide mixed with different materials.

Next, a method for forming a deposited film of an inorganic oxide in the present invention will be described. Examples of such a method include a physical vapor deposition method such as a vacuum deposition method, a sputtering method, and an ion plating method. Physica
l Vapor Deposition method, PVD
Method) or a chemical vapor deposition method such as plasma-enhanced chemical vapor deposition, thermal chemical vapor deposition, or photochemical vapor deposition (Che).
medical Vapor Deposition method, CV
D method) and the like. In the present invention, the method for forming a vapor-deposited film of an inorganic oxide will be described more specifically. The metal oxide as described above is used as a raw material, and this is heated to be vapor-deposited on the surface of a multilayer polypropylene film. Oxidation reaction deposition method in which a metal or metal oxide is used as a raw material, oxygen is introduced and oxidized to deposit on the surface of the multilayer polypropylene film, and plasma-assisted oxidation in which the oxidation reaction is further assisted by plasma An evaporation film can be formed by a reactive evaporation method or the like. Further, in the present invention, when forming a deposited film of silicon oxide, the deposited film can be formed by a plasma chemical vapor deposition method using organosiloxane as a raw material. In the present invention, when producing a transparent barrier film used as a packaging material, a vacuum evaporation method or a plasma chemical vapor deposition method is mainly used.

In the present invention, the above-described vacuum vapor deposition method will be specifically described. FIG. 4 is a schematic configuration diagram showing an example of a vacuum vapor deposition method using a roll-up type vacuum vapor deposition apparatus. As shown in FIG. 4, the unwinding roll 2 is placed in a vacuum chamber 22 of a winding type vacuum evaporation apparatus 21.
3 is fed out of the multi-layer polypropylene film 24, and the multi-layer polypropylene film 24 is further cooled via guide rolls 25 and 26 to a cooled coating drum 27.
To guide. Thus, the multilayered polypropylene film 24 guided on the cooled coating drum 27
For example, aluminum (metal), aluminum oxide, or the like is used as the evaporation source 28 on the surface of the substrate, and these are put in a crucible 29, and aluminum (metal) heated in the crucible 29 or aluminum oxide is used. Is evaporated, and at this time, a vapor deposition film of aluminum oxide is formed through the masks 31 and 31 while oxygen gas or the like is ejected from the oxygen outlet 30. Then, a vapor deposition film of aluminum oxide is formed on the surface of the aluminum oxide film. The multi-layered polypropylene film 24 formed as above is wound up on a winding roll 32 via guide rolls 25 'and 26', whereby the transparent barrier film according to the present invention can be manufactured. In the present invention, the thickness of the thin film mainly composed of the deposited film of aluminum oxide as the deposited film of the inorganic oxide is preferably about 50 to 300 °, more preferably about 100 to 250 °. Therefore, in the above, when the thickness is more than 300 ° and further 250 °,
It is not preferable because the flexibility of the film is reduced and cracks and the like are easily generated in the film.
If it is less than 00 °, it is not preferable because it is difficult to exhibit effects such as barrier properties. In the above, for example, an electron beam (EB) method, a high-frequency induction heating method, a resistance heating method, or the like is used as a method for heating the deposition material. The above example is an example of a method for producing a transparent barrier film according to the present invention by forming a vapor-deposited film of an inorganic oxide using the vacuum vapor deposition method,
The present invention is not limited by this example.

Next, in the present invention, the above-mentioned plasma enhanced chemical vapor deposition method will be described. FIG. 5 is a schematic configuration diagram illustrating an example of a plasma enhanced chemical vapor deposition method using a plasma enhanced chemical vapor deposition apparatus. As shown in FIG. 5, first, a multi-layer polypropylene film 44 is unwound from an unwinding roll 43 disposed in a vacuum chamber 42 of a plasma chemical vapor deposition apparatus 41, and further, is fixed through an auxiliary roll 45. It is conveyed at a speed and supplied onto the cooling / electrode drum 46 peripheral surface. Next, in the present invention, the raw material volatile supply device 4
From 7, 48, and 49, for example, a monomer gas for vapor deposition of an organic silicon compound or the like, an oxygen gas, an inert gas, or a mixed gas for vapor deposition composed of other materials is introduced into the vapor deposition chamber 42 through the raw material supply nozzle 50; The glow discharge plasma 51 deposits a deposited film of an inorganic oxide such as silicon oxide on the surface of the multilayer polypropylene film 44 on the peripheral surface of the cooling / electrode drum 46 to form a film. Thus, a predetermined voltage is applied to the cooling / electrode drum 46 from a power source 52 disposed outside the vacuum chamber 42, and a magnet 53 is provided near the cooling / electrode drum 46.
Is disposed to promote the generation of plasma 51, and then a multi-layered polypropylene film 44 on which a vapor-deposited film of an inorganic oxide such as silicon oxide is formed on the surface layer,
4 and wound up on a take-up roll 55 to produce the transparent barrier film of the present invention.
In the figure, reference numeral 56 denotes a vacuum pump. The above example is an example of a method for producing a transparent barrier film according to the present invention by forming an evaporated film of an inorganic oxide such as silicon oxide using a plasma enhanced chemical vapor deposition method. It is not limited by.

In the above, the thin film mainly composed of a deposited film of silicon oxide as a deposited film of an inorganic oxide is made of a silicon compound having at least silicon and oxygen as constituent elements, and further, carbon or carbon as a trace constituent element. It contains one or more elements of hydrogen, and has a film thickness of about 50 to 300 °, more preferably 100 to 25 °, as described above.
0 ° is desirable, so in the above, 300 °,
Further, when the thickness is more than 250 °, the flexibility of the film is reduced and cracks and the like are easily generated in the film, which is not preferable. In addition, when the thickness is less than 50 °, and further less than 100 °, the barrier property etc. This is not preferable because it is difficult to achieve the effect. Thus, in the present invention, as the silicon oxide vapor deposition film as described above, an organic silicon compound is used as a raw material, and a vapor deposition film formed by a plasma chemical vapor deposition method using a low-temperature plasma generator or the like is used. can do. In the above, as the organic silicon compound, for example, 1.1.3.3-tetramethyldisiloxane, hexamethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethyl Silane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane,
Phenyltrimethoxysilane, methyltriethoxysilane, octamethylcyclotetrasiloxane, and the like can be used. In the present invention, among the above-mentioned organosilicon compounds, the use of 1.1.3.3-tetramethyldisiloxane or hexamethyldisiloxane as a raw material is advantageous in terms of handleability and formed deposited film. It is a particularly preferable raw material in view of its properties and the like. In addition, as the inert gas, for example, an argon gas, a helium gas, or the like can be used. Furthermore, in the above, as the low-temperature plasma generator, for example, a high-frequency plasma, a pulse wave plasma, a microwave plasma or the like may be used.
In the present invention, in order to obtain highly active and stable plasma, it is desirable to use a generator using a high-frequency plasma method.

In the present invention, since a multilayer polypropylene film is inferior in heat resistance, it is preferable to form a deposited film of an inorganic oxide such as silicon oxide by a physical vapor deposition method (PVD method) such as a vacuum deposition method. Since the multi-layer polypropylene film causes phenomena such as thermal degradation or thermal shrinkage, and it may be difficult to form a sufficiently satisfactory vapor-deposited film, it is difficult to form a vapor-deposited film at a low temperature. It is preferable to form a vapor deposition film using a vapor deposition method (CVD method). Thus, in the present invention, in the above-mentioned plasma chemical vapor deposition method (CVD method), a mixed gas composition for vapor deposition comprising a monomer gas for vapor deposition of an organic silicon compound, an oxygen gas, an inert gas, and the like is used as a raw material. When introduced into the vacuum chamber through the supply nozzle, the content of the oxygen gas is increased in the composition of the mixed gas composition for vapor deposition, while the content of the monomer gas for vapor deposition is reduced. Increase the current of plasma power,
The voltage value is reduced, and plasma irradiation is performed under mild conditions, thereby forming a vapor-deposited film that is thin, transparent, and has excellent flexibility and oxygen gas barrier properties. On the other hand, it is possible to form an evaporated film having a slightly poor water vapor barrier property. By the way, the multilayer polypropylene film itself has a water vapor barrier property of about 5 to 6 g / m ² / day, which is extremely excellent. It can supplement itself, thereby improving the oxygen gas barrier property by the vapor deposition film, and the multi-layer polypropylene film itself has excellent water vapor barrier property, such as silicon oxide which is excellent in oxygen gas barrier property, water vapor barrier property, etc. It is possible to produce a transparent barrier film composed of a multilayer polypropylene film having an inorganic oxide vapor-deposited film.

Further, in the present invention, in the above-mentioned plasma chemical vapor deposition method (CVD method), a mixed gas composition for vapor deposition comprising a monomer gas for vapor deposition of an organic silicon compound or the like, an oxygen gas, an inert gas, etc. Is introduced into the vacuum chamber through the raw material supply nozzle, when the content of the oxygen gas is increased and the content of the monomer gas for the deposition is reduced in the composition of the mixed gas composition for the deposition, the The ratio of the polar portion of the deposited film increases, as a result, the adhesion between the base film and the deposited film, that is, the multilayer polypropylene film and the deposited film of an inorganic oxide such as silicon oxide is improved, and By improving the adhesion between the two, the oxygen gas barrier property is also improved. Further, in the present invention, when the content of the oxygen gas is increased as described above, and the content of the monomer gas for deposition is reduced, and the plasma chemical vapor deposition is performed, a deposition film of an inorganic oxide such as silicon oxide is formed. In this case, the silicon oxide vapor-deposited film comprises a silicon oxide vapor-deposited continuous thin film represented by the formula SiO _X ,
Can be increased, and a vapor-deposited thin film having extremely excellent transparency can be formed. Furthermore,
In the present invention, the content of the oxygen gas is increased as described above, while the content of the monomer gas for vapor deposition is reduced, and the plasma chemical vapor deposition is performed. When forming the vapor deposition film, the oxygen plasma gas increases. From this, yellowing of the multilayer plastic film as a base film is suppressed, as a result,
This makes it possible to improve the transparency of a transparent barrier film composed of a multilayer polypropylene film having a deposited film of an inorganic oxide such as silicon oxide.

In the present invention, when performing the plasma chemical vapor deposition, the content of the oxygen gas in the mixed gas composition for vapor deposition containing at least a monomer gas for vapor deposition, an oxygen gas, and an inert gas is as follows. Specifically, in the composition of the mixed gas composition for vapor deposition, it is preferable that the content be contained in the range of about 75% or more. In the above, if the content is less than 75%, it becomes difficult to obtain a vapor-deposited thin film having excellent oxygen gas barrier properties, and further, if the amount of oxygen gas is reduced, the multilayer plastic film tends to turn yellow. As the gas volume decreases,
Conversely, the content ratio of the monomer gas for vapor deposition or the inert gas increases, which is not preferable because the yellowing of the multilayer plastic film tends to increase remarkably. Incidentally, the content of oxygen gas as described above is, for example, in the case of the optimal conditions for performing plasma-enhanced chemical vapor deposition using a biaxially stretched polyethylene terephthalate film or a biaxially stretched nylon film as a base film for vapor deposition. In comparison with, the amount is about twice as large.

In the present invention, when performing the plasma chemical vapor deposition, at least a monomer gas for vapor deposition,
Oxygen gas, and, in the mixed gas composition for vapor deposition containing an inert gas, as the content of the monomer gas for vapor deposition,
Specifically, in the composition of the mixed gas composition for vapor deposition,
It is preferred that the content be within about 5% or less. In the above, when the content of the vapor deposition monomer gas exceeds 5%, the concentration of the vapor deposition monomer gas becomes high in the vapor deposition mixed gas composition, and the thickness of the formed vapor deposition film becomes high. This is undesirable because the flexibility is reduced.

In the present invention, the composition of the mixed gas for vapor deposition includes at least a monomer gas for vapor deposition in a range of 2.5 to 5%, an oxygen gas in a range of 75% or more, and A mixed gas composition for vapor deposition containing an inert gas in a range of 5 to 20% and further containing other components, if necessary, can be used. In the above, for example, the monomer gas for vapor deposition is
If it is less than 2.5%, it is not preferable because a vapor-deposited film can hardly be formed on the multilayer polypropylene film, and sufficient barrier properties cannot be obtained. In the present invention, the inert gas contains 5%
If the amount is less than 20%, the plasma becomes unstable, which is not preferable. If the amount exceeds 20%, the amount of the mixed gas for vapor deposition (monomer, oxygen gas, etc.) is reduced. It is not preferable because it becomes difficult to form. The unit of% is based on the volume ratio.

Further, in the present invention, it is preferable to use a mixed gas composition for vapor deposition having a content ratio of oxygen gas / monomer gas for vapor deposition of 10 or more as the above-mentioned mixed gas composition for vapor deposition. . Thus, in the present invention, the content ratio of oxygen gas / monomer gas for vapor deposition is preferably from 10 to 30. As described above, if the content ratio of oxygen gas / monomer gas for vapor deposition is less than 10, it is not preferable because it becomes difficult to form a vapor-deposited film having a sufficient oxygen barrier property.
If the content ratio of the monomer gas for vapor deposition exceeds 30, it is not preferable because the film quality of the vapor deposited film hardly changes.

Next, in the present invention, the above-mentioned mixed gas composition for vapor deposition is introduced into a vacuum chamber through a raw material supply nozzle, and a vapor-deposited film of an inorganic oxide such as silicon oxide is formed by glow discharge plasma. It is preferable to form the film on a multi-layer polypropylene film and form a film. At this time, the cooling / electrode drum is supplied with a current of less than 10 kW from a power source disposed outside the chamber. It is desirable to carry out plasma chemical vapor deposition under mild conditions to produce a transparent barrier film having a continuous thin film of inorganic oxide vapor deposition. In the above, when the current value exceeds 10 kW, the conditions of plasma chemical vapor deposition become severe, for example, a multilayer polypropylene film is
In response to the impact, yellowing or deterioration occurs, which makes it difficult to suppress the occurrence. In addition, the plasma becomes unstable, and the arcing phenomenon becomes very likely to occur, resulting in poor plasma resistance. This is not preferable because a large number of holes are likely to be formed in the multilayer polypropylene film, and it is difficult to form a vapor-deposited thin film having excellent oxygen gas barrier properties.

Next, in the present invention, the silicon oxide deposited film by the plasma chemical vapor deposition method constituting the transparent barrier film according to the present invention is represented by the formula SiO _x (where X is
Is a continuous vapor-deposited thin film mainly composed of silicon oxide represented by the number of 0 to 2, and further, from the viewpoint of transparency, barrier properties and the like, the formula SiO _x (where X is 1) 0.3 to 1.9
Represents the number of It is preferable that the thin film is mainly composed of a silicon oxide deposited film represented by the formula (1). Further, the above-mentioned deposited thin film of silicon oxide is made of silicon oxide containing silicon and oxygen as constituent elements, and is made of one or more kinds of trace constituent elements consisting of carbon, hydrogen, silicon, or oxygen. It consists of a vapor-deposited continuous thin film of silicon oxide containing at least one compound. Further, when the silicon oxide vapor-deposited thin film contains a compound made of carbon, the content of carbon is reduced in the depth direction of the film thickness. Thus,
The film structure of the above-described deposited film is, for example, an X-ray photoelectron spectrometer (Xray Photoelectron Sp).
, Electroncopy, XPS), Secondary Ion Mass Spectrometer (Secondary Ion Mass Spe
This can be confirmed by analyzing the deposited film using a method of analyzing the surface by ion etching in the depth direction using a surface analysis device such as troscopy (SIMS).

The transparent barrier film according to the present invention comprises:
The surface layer uses a multilayer polypropylene film composed of a low-melting point polypropylene resin layer, and since an inorganic oxide vapor-deposited film is provided on the surface thereof, during vapor deposition, particularly, during plasma vapor deposition, as a base film. The multilayer polypropylene film prevents the influence of the impact and the like. In the present invention, since the surface layer is composed of the low melting point polypropylene resin layer, crystallization after stretching during film formation is unlikely to occur, and a lamella structure is unlikely to be formed. As a result, deterioration due to plasma or the like during vapor deposition occurs It is presumed to be due to the absence. Even if the multi-layer polypropylene film as the base film is affected by the plasma irradiation during the plasma deposition and the polypropylene resin constituting the surface layer is decomposed, deteriorated, etc., the surface layer is composed of a low melting point polypropylene resin layer. Therefore, the decomposed and degraded components enter into the molten polypropylene resin layer further below, and structurally form a polypropylene resin film that is different from the previous and has higher strength. It is presumed that there is. Further, in the transparent barrier film according to the present invention, as a multilayer polypropylene film, when the intermediate layer, when using a multilayer polypropylene film containing a barrier resin layer,
The barrier properties exhibit a synergistic effect with the barrier properties of the inorganic oxide vapor-deposited film, thereby enabling production of a transparent barrier film having extremely excellent high barrier properties.

The transparent barrier film according to the present invention produced as described above is, for example, a packaging material constituting a packaging container such as a resin film, a paper base material, a metal material, synthetic paper, cellophane, etc. The present invention is capable of producing various composite films by, for example, laminating, and producing a packaging material suitable for filling and packaging various articles. As the resin film, specifically, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene,
Polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid or methacrylic acid copolymer, acid-modified polyolefin resin, methylpentene polymer -, Polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, vinyl chloride-vinylidene chloride copolymer, poly (meth) acrylic resin, polyacrylonitrile resin, polystyrene resin Acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polyester resin, polyamide resin, polycarbonate resin, polyvinyl alcohol resin, Ethylene-vinyl acetate copolymer Products, fluorine-based resins, diene resins, polyacetal - Le resins, polyurethane resins, nitrocellulose - scan, film or sheet of a known resin other like - Select from them on any can be used. In the present invention, the film or sheet is unstretched,
Any material such as one stretched in a uniaxial or biaxial direction can be used. The thickness is arbitrary, but can be selected from a range of several μm to 300 μm. Further, in the present invention, the film or sheet may be any film such as an extruded film, an inflation film or a coating film. Further, in the above, as the paper substrate, for example, a paper substrate such as a strongly sized bleached or unbleached paper, a paper substrate such as pure white roll paper, kraft paper, paperboard, or processed paper, or the like is used. can do. In the above, as the paper base material constituting the paper layer, it is desirable to use a base material having a basis weight of about 80 to 600 g / m ² , preferably a base weight of about 100 to 450 g / m ² . Further, in the above, as the metal material, for example, aluminum foil, or
A resin film having an aluminum evaporated film or the like can be used.

Next, a method of manufacturing a composite film using the above-mentioned materials in the present invention will be described. Examples of the method include a method of laminating an ordinary packaging material, for example, a wet method. Lamination method, dry lamination method, solventless dry lamination
It can be performed by an extrusion method, an extrusion lamination method, a T-die extrusion molding method, a co-extrusion lamination method, an inflation method, a co-extrusion inflation method, or the like. Thus, in the present invention, when performing the above-mentioned lamination, if necessary, for example, a pre-treatment such as a corona treatment, an ozone treatment, a framing treatment, or the like can be performed on the film. Anchor coating agents such as polyester, isocyanate (urethane), polyethyleneimine, polybutadiene, and organic titanium, or polyurethane, polyacryl, polyester, epoxy, and polyvinyl acetate , Cellulo
Known anchor coating agents, adhesives and the like, such as adhesives for laminating, and other laminating materials, can be used.

Next, in the present invention, a method for producing a bag or a box using the above composite film will be described. For example, when the packaging container is a soft packaging bag made of a plastic film or the like, Using a composite film manufactured by such a method, the heat-sealing resin layer of the inner layer is made to face the surface, and it is folded or two sheets are overlapped, and the peripheral edge is further cut. A bag can be formed by providing a seal portion by heat sealing. Thus, as a bag making method, the above composite film is
The inner layer is bent with its surfaces facing each other, or the two sheets are overlapped, and the peripheral edge of the outer periphery is formed, for example, into a side seal type, a two-way seal type, a three-way seal type, a four-way seal type. Seal type, seal type with envelope, seal type with seal (pillow seal type), seal type with folds, flat bottom type, square bottom type, etc. The heat seal depends on the heat seal form.
To produce various types of packaging containers according to the present invention. In addition, for example, a self-supporting packaging bag (standing pouch) can be manufactured,
Further, in the present invention, a tube container or the like can be manufactured using the above-mentioned composite film. In the above, as a method of heat sealing, for example,
Roll, rotary roll seal, belt seal, impulse seal
It can be performed by a known method such as a seal, a high-frequency seal, an ultrasonic seal, or the like. In the present invention, a spout such as a one-piece type, a two-piece type, or the like, or a zipper for opening and closing can be arbitrarily attached to the packaging container as described above.

Next, in the case of a liquid-filled paper container containing a paper substrate as a packaging container, for example, a composite film in which a paper substrate is laminated is produced as a laminate, and a desired paper container is produced therefrom. A blank plate is manufactured, and thereafter, a body, a bottom, a head and the like are manufactured using the blank plate to manufacture, for example, a liquid paper container of a brick type, a flat type or a gable-top type. be able to. Moreover, the shape can be manufactured by any of a rectangular container, a circular or other cylindrical paper can, and the like.

In the present invention, the packaging container produced as described above is excellent in transparency, gas barrier properties against oxygen, water vapor, etc., impact resistance, and the like.
Having post-processing suitability such as printing, bag making or box making,
In addition, to prevent the peeling of the deposited thin film as a barrier film, and, to prevent the occurrence of thermal cracks, to prevent its degradation, to exhibit excellent resistance as a barrier film, for example,
Food and drink, medicine, detergent, shampoo, oil, toothpaste,
It is excellent in suitability for packing and preservation of various articles such as chemicals and cosmetics such as adhesives and pressure-sensitive adhesives, and other properties.

[0028]

The present invention will be described more specifically with reference to the following examples. Example 1 (1). Two types of polypropylene resins having different melting points are used, and the surface layer is composed of a low melting point polypropylene resin layer.
Co-extruded biaxially stretched multi-layer polypropylene film with a thickness of 20 μm (trade name, C, manufactured by Nimura Chemical Industry Co., Ltd.)
KK-H) and mounted on a delivery roll of a plasma-enhanced chemical vapor deposition apparatus, and having a thickness of 184 mm under the following conditions.
Was formed on the surface of the biaxially stretched multilayer polypropylene film to produce a transparent barrier film according to the present invention. Reaction gas mixture ratio: hexamethyldisiloxane: oxygen gas: helium = 0.5: 10: 2 (unit: slm) Degree of vacuum in vacuum chamber: 5.0 × 10 ⁻⁶ mbar Degree of vacuum in evaporation chamber : 9.0 × 10 ⁻³ mbar Cooling / electrode drum supply power: 10 kW Deposition surface: Corona treated surface (2). Next, the surface of the vapor-deposited thin film of silicon oxide of the transparent barrier film produced above was subjected to a plasma treatment under the following conditions. As a result, the surface tension of the surface of the deposited silicon oxide thin film was changed from 42 dyn to 68 dyn, and the wettability was improved. Plasma supply power: 3 kW Plasma gas: Mixed gas of helium (He) and oxygen (O ₂ ) (3). Next, the plasma-treated transparent barrier film was used, and the film was mounted on one of the rolls of a dry laminator coater, and an adhesive layer was formed on the silicon oxide vapor-deposited thin film surface. On the other hand, a non-stretched polypropylene film having a thickness of 40 μm, which is a sealant film, is mounted on the other delivery roll, and then both are dry-laminated under the following conditions to obtain a composite film. Was manufactured. Adhesive layer: Use urethane-based adhesive (Main agent) Urethane-based (manufactured by Takeda Pharmaceutical Co., Ltd., trade name, Takenet A-515) (Curing agent) Isocyanate-based (manufactured by Takeda Pharmaceutical Co., Ltd., product (A-50) (Mixing ratio) Main agent: Curing agent = 10: 1 (Solvent) Ethyl acetate (Coating amount) 4.0 g / m ² (Dry)

Embodiment 2 (1). Two types of polypropylene resins having different melting points and a saponified ethylene-vinyl acetate copolymer are used, the surface layer of which is composed of a low-melting polypropylene resin layer, and the intermediate layer is a saponified ethylene-vinyl acetate copolymer. Of a biaxially stretched multi-layer polypropylene film having a thickness of 20 μm and extruded from a co-extruded three-layered two-layer, three-layer film made of a compound, is mounted on a delivery roll of a plasma-enhanced chemical vapor deposition apparatus. The deposited thin film of silicon oxide of 179 °
A transparent barrier film according to the present invention was produced by forming the film on the surface of an axially stretched multilayer polypropylene film. Reaction gas mixture ratio: hexamethyldisiloxane: oxygen gas: helium = 0.5: 10: 2 (unit: slm) Degree of vacuum in vacuum chamber: 5.0 × 10 ⁻⁶ mbar Degree of vacuum in evaporation chamber : 9.0 × 10 ⁻³ mbar Cooling / electrode drum supply power: 10 kW Deposition surface: Corona treated surface (2). Next, the surface of the vapor-deposited thin film of silicon oxide of the transparent barrier film produced above was subjected to a plasma treatment under the following conditions. As a result, the surface tension of the surface of the deposited thin film of silicon oxide was changed from 39 dyn to 68 dyn, and the wettability was improved. Plasma supply power: 3 kW Plasma gas: Mixed gas of helium (He) and oxygen (O ₂ ) (3). Next, the plasma-treated transparent barrier film was used, and the film was mounted on one of the rolls of a dry laminator coater, and an adhesive layer was formed on the silicon oxide vapor-deposited thin film surface. On the other hand, a non-stretched polypropylene film having a thickness of 40 μm, which is a sealant film, is mounted on the other delivery roll, and then both are dry-laminated under the following conditions to obtain a composite film. Was manufactured. Adhesive layer: Use urethane-based adhesive (Main agent) Urethane-based (manufactured by Takeda Pharmaceutical Co., Ltd., trade name, Takenet A-515) (Curing agent) Isocyanate-based (manufactured by Takeda Pharmaceutical Co., Ltd., product (A-50) (Mixing ratio) Main agent: Curing agent = 10: 1 (Solvent) Ethyl acetate (Coating amount) 4.0 g / m ² (Dry)

Comparative Example 1 (1). A biaxially-stretched polypropylene film having a thickness of 20 μm (trade name, FOK, manufactured by Nimura Chemical Industry Co., Ltd.) was used, and was mounted on a delivery roll of a plasma-enhanced chemical vapor deposition apparatus. Was formed on the surface of the biaxially stretched multilayer polypropylene film to produce a transparent barrier film according to the present invention. Reaction gas mixture ratio: hexamethyldisiloxane: oxygen gas: helium = 0.5: 10: 2 (unit: slm) Degree of vacuum in vacuum chamber: 5.0 × 10 ⁻⁶ mbar Degree of vacuum in evaporation chamber : 6.0 × 10 ⁻³ mbar Cooling / electrode drum supply power: 10 kW Deposition surface: Corona treated surface (2). Next, the surface of the vapor-deposited thin film of silicon oxide of the transparent barrier film produced above was subjected to a plasma treatment under the following conditions. As a result, the surface tension of the surface of the deposited silicon oxide thin film was changed from 42 dyn to 68 dyn, and the wettability was improved. Plasma supply power: 3 kW Plasma gas: Mixed gas of helium (He) and oxygen (O ₂ ) (3). Next, the plasma-treated transparent barrier film was used, and the film was mounted on one of the rolls of a dry laminator coater, and an adhesive layer was formed on the silicon oxide vapor-deposited thin film surface. On the other hand, a non-stretched polypropylene film having a thickness of 40 μm, which is a sealant film, is mounted on the other delivery roll, and then both are dry-laminated under the following conditions to obtain a composite film. Was manufactured. Adhesive layer: Use urethane-based adhesive (Main agent) Urethane-based (manufactured by Takeda Pharmaceutical Co., Ltd., trade name, Takenet A-515) (Curing agent) Isocyanate-based (manufactured by Takeda Pharmaceutical Co., Ltd., product (A-50) (Mixing ratio) Main agent: Curing agent = 10: 1 (Solvent) Ethyl acetate (Coating amount) 4.0 g / m ² (Dry)

Experimental Examples The following data were measured for each of the transparent barrier films and the composite films produced in Examples 1 and 2 and Comparative Example 1. (1). Measurement of Oxygen Permeability This is a condition of 23 ° C. and 90% RH in the United States.
The measurement was carried out using a measuring instrument (model name, OXTRAN) manufactured by MOCON. (2). Measurement of water vapor transmission rate This is a condition of temperature of 40 ° C and humidity of 90% RH in the United States,
The measurement was carried out using a measuring instrument (model name, PERMATRAN) manufactured by MOCON. (3). Color evaluation This is performed by visually observing coloring, measuring with a Macbeth densitometer, and using a color computer manufactured by Suga Test Instruments Co., Ltd.
Evaluation was made by measurement using a tar. -Observation of the coloring by visual observation was performed using a transparent barrier film of 10
The sheets were stacked and visually observed directly. The measurement with a Macbeth densitometer was performed on one transparent barrier film at a total light transmittance of a wavelength of 500 nm. The measurement with a color computer was performed with one transparent barrier film. Measurement conditions: (light source) C2 degree (measurement mode) transmission mode (evaluation value) Yellowness (Yi: the larger the value, the more yellow) (4). Measurement of Laminate Strength This was measured for the composite film after aging using Tensilon. (5). Measurement of flex resistance This is based on the composite film
After bending, the oxygen gas barrier property was measured. The oxygen gas barrier properties were measured as described above. About the above-mentioned measurement result, the following Table 1, Table 2, and Table 3
Shown in

(Table 1) Measurement of oxygen permeability and water vapor permeability In Table 1 above, the oxygen permeability is cc / m ² / da
The unit is y · 23 ° C. · 90% RH, and the water vapor permeability is the unit of g / m ² / day · 40 ° C. · 100% RH.

[0033]

(Table 3) Measurement of laminate strength and flex resistance In Table 3 above, the unit of oxygen permeability is the same as described above.

(1). As is clear from the results of Tables 1 to 3, the oxygen gas barrier property of the example 1 was inferior to that of the comparative example 1, but the oxygen gas barrier property of the example 2 was intermediate between the multilayer polypropylene films. By providing the layer with a barrier resin layer, oxygen gas barrier properties could be greatly improved, and performance equal to or better than that of Comparative Example 1 could be obtained. (2). Regarding transparency and the like, those of Examples 1 and 2 and Comparative Example 1 were almost the same. (3). Regarding the laminate strength, those of Examples 1 and 2 were significantly improved over those of Comparative Example 1. This is considered to be due to the fact that in Examples 1 and 2, the multilayer polypropylene film as the base film was able to prevent deterioration or the like in the vicinity of the surface layer by plasma irradiation or the like during vapor deposition. Next, regarding the bending resistance, those of Examples 1 and 2 were superior to those of Comparative Example 1. This means that, in Examples 1 and 2, similarly to the above, the multilayer polypropylene film as the base film can suppress deterioration due to plasma irradiation at the time of vapor deposition,
It is presumed that this was due to the fact that sufficient laminate intensity could be obtained. On the other hand, in Comparative Example 1, when the biaxially stretched polypropylene film as the base film was laminated due to deterioration due to plasma irradiation or the like at the time of vapor deposition, distortion near the surface layer of the biaxially stretched polypropylene film, cracks and the like in the vapor deposited layer were observed. This is considered to be due to the fact that the oxygen gas barrier property was reduced by these.

[0036]

As is apparent from the above description, the present invention uses a biaxially stretched polypropylene film as a base film, and applies a plasma chemical vapor deposition method or the like to one surface of the biaxially stretched polypropylene film. In forming a deposited thin film of an inorganic oxide such as silicon oxide by utilizing, at least, the surface layer, paying attention to using a multilayer polypropylene film composed of a low melting point polypropylene resin layer, on the surface layer of the multilayer polypropylene film, A transparent barrier film is manufactured by providing a vapor-deposited film of an inorganic oxide such as silicon oxide by using a plasma chemical vapor deposition method or the like, and the multilayer polypropylene film as a base film has a lamellar structure change due to plasma irradiation. Deterioration of strength etc. is not recognized, and its yellowing is also prevented, furthermore, it is excellent in transparency,
And, it is rich in flexibility, and can also form a vapor-deposited thin film of an inorganic oxide such as silicon oxide having excellent oxygen gas barrier properties and water vapor barrier properties, and can be formed of another resin film or a paper base material. Laminated with packaging materials, for example, food and drink,
It is possible to produce a transparent barrier film useful for producing a packaging container or the like suitable for filling and packaging various articles such as pharmaceuticals, cosmetics, detergents, and the like.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a layer configuration of an example of a transparent barrier film according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a layer configuration of an example of a multilayer polypropylene film in the present invention.

FIG. 3 is a schematic cross-sectional view showing a layer configuration of another example of the multilayer polypropylene film in the present invention.

FIG. 4 is a schematic configuration diagram illustrating an example of a vacuum deposition method using a roll-up type vacuum deposition apparatus.

FIG. 5 is a schematic configuration diagram illustrating an example of a plasma enhanced chemical vapor deposition method using a plasma enhanced chemical vapor deposition apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Transparent barrier film 2 Low-melting-point polypropylene resin layer 3 Multilayer polypropylene film 4 Deposition film of inorganic oxide 11, 12, ..., 00 Polypropylene resin layer 11a Barrier resin layer A Multilayer polypropylene film A ₁ Multilayer polypropylene film 21 Winding Type vacuum evaporation apparatus 22 Vacuum chamber 23 Unwinding roll 24 Multilayer polypropylene film 25, 26 Guide roll 27 Coating drum 28 Evaporation source 29 Crucible 30 Oxygen outlet 31 Mask 25 ', 26' Guide roll 32 winding Take-off roll 41 Plasma chemical vapor deposition device 42 Vacuum chamber 43 Unwinding roll 44 Multi-layer polypropylene film 45 Auxiliary roll 46 Cooling / electrode drum 47, 48, 49 Raw material volatile supply device 50 Raw material supply nozzle 51 Gross Conductive plasma 52 Power 53 magnet 54 assist Russia - le 55 winding Russia - le 56 vacuum pump

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // C08L 23:10 F term (Reference) 4F006 AA12 AB74 BA05 CA07 DA01 4F071 AA20 AB18 AF08 AH04 BA01 BB06 BB08 BB11 BC01 4F100 AA17C AA20C AK07A AK07B AK07D AK51G BA04 BA07 BA10A BA10D BA26 CB01 EH66C EJ38B EJ38D GB15 JA04A JA04B JA04D JD03 JD04 JN01 4K030 AA06 AA09 AA14 BA42 BA04 CA07 FA12 GA03

Claims (8)

[Claims] 1. A transparent barrier film characterized in that at least a surface layer of a multilayer polypropylene film comprising a low melting point polypropylene resin layer is provided with an inorganic oxide vapor-deposited film. 2. The transparent barrier film according to claim 1, wherein the low melting point polypropylene resin layer comprises a polypropylene resin layer containing a low melting point polypropylene resin. 3. The transparent barrier film according to claim 1, wherein the low-melting-point polypropylene resin layer is a polypropylene resin layer made of only a low-melting-point polypropylene resin. 4. The multilayer polypropylene film has at least 2 points whose melting points are sequentially increased from the surface layer toward the inner layer.
4. The transparent barrier film according to claim 1, comprising a multi-layer polypropylene film comprising at least one polypropylene resin layer. 5. The multilayer polypropylene film according to claim 1, wherein the multilayer polypropylene film is a biaxially stretched multilayer polypropylene film that has been biaxially stretched.
4. The transparent barrier film described in 1. 6. The transparent barrier according to claim 1, wherein the inorganic oxide deposited film is an inorganic oxide deposited film formed by a chemical vapor deposition method. Film. 7. The transparent material according to claim 1, wherein the inorganic oxide vapor-deposited film is an inorganic oxide vapor-deposited film formed by a plasma enhanced chemical vapor deposition method. Barrier film. 8. The method according to claim 1, wherein the inorganic oxide deposited film is a silicon oxide deposited film formed by a plasma enhanced chemical vapor deposition method. Transparent barrier film.