JP4648935B2 - Gas barrier film manufacturing method and gas barrier film manufacturing apparatus - Google Patents

Description

The present invention relates to a gas barrier film manufacturing method and a gas barrier film manufacturing apparatus .

  Conventionally, various image display devices, electronic display element substrates, solar cell substrates, and the like have been described as being important for their ability to transmit gas and water vapor (hereinafter also referred to as “gas barrier properties”). Therefore, the use of a glass plate has been widely performed.

  Certainly, when a glass plate is used for the substrate, various gases and water vapor do not pass through the glass plate, so that those located inside the glass plate are protected from various gases and water vapor from the outside. However, on the other hand, problems in handling such as easy breakage of the glass plate and increase in weight have been pointed out.

  Therefore, a transparent plastic film has been attracting attention as a substrate that is flexible, difficult to break, and lightweight against a relatively heavy glass plate that is easily broken.

  However, since the plastic film permeates gas and water vapor, the plastic film does not have the gas barrier property as described above, and therefore, the plastic film cannot be used as it is without any processing.

  Accordingly, various studies have been made to develop a plastic film having a gas barrier property (hereinafter also referred to as “gas barrier film”) by applying some processing or treatment to the plastic film. In the early stages of development, development related to laminating metal on the surface of a plastic film has been made, but eventually it becomes an important theme to obtain transparency as well as gas barrier properties, and there is also a demand for improving gas barrier properties. While growing, while maintaining transparency by laminating thin film layers made mainly of oxides, nitrides, oxynitrides, fluorides, etc. of silicon, aluminum, indium, magnesium, etc. on the surface of plastic films Various attempts have been made to obtain higher gas barrier properties.

In order to simply laminate such a group of materials on the surface of a transparent plastic film, a physical vapor deposition method (hereinafter also referred to as “PVD method”), a chemical vapor deposition method (hereinafter referred to as “CVD method”). Or a coating method (hereinafter also referred to as “sol-gel method”). Among these methods, it can be said that the use of the CVD method is most suitable for producing a gas barrier film. This is because when PVD method is used, certainty at the time of lamination is not sufficient, high vacuum conditions are required, and further, cracks are likely to occur in the laminate, that is, gas barrier properties are impaired from cracks. In the case of the sol-gel method, a coating solution obtained by dissolving a raw material in a solvent is applied onto a plastic film and then dried. This is because it is very difficult to secure a necessary and sufficient gas barrier property by generating a large bubble.

  Thus, it can be said that it is theoretically preferable to use a method called a plasma chemical vapor deposition method (plasma CVD method) for producing a gas barrier film. This is because the plastic film used as the base material of the gas barrier film is vulnerable to high heat treatment, and the high temperature applied to the base material in the plasma CVD method is a temperature that can withstand even a plastic film. When a certain substance is laminated on the surface of the plastic film, it can be said that the plasma CVD method is preferable.

  For example, Patent Document 1 discloses this plasma CVD method as an invention that provides a method of improving the yield and improving the film forming speed accordingly.

JP 2005-200710 A

  The invention disclosed in Patent Document 1 is a method for quickly and efficiently vapor-depositing by devising a plasma discharge method if necessary, and according to such a method, a gas barrier film can be quickly obtained with high yield. Can be obtained.

  However, with this alone, it is possible to obtain a gas barrier film with good yield and quickly, and to obtain a gas barrier film that maintains the flexibility as a film while maintaining the high gas barrier property that is the original problem. It cannot be said to have responded enough.

  That is, the invention described in Patent Document 1 efficiently manufactures a gas barrier film having characteristics equivalent to those of a conventional product. Compared with the properties of a conventional product, which has recently been increasing in demand, However, it has not been able to meet the market demand for improving flexibility and ensuring flexibility as before.

The present invention has been made in view of such problems, and the object thereof is to be found in conventional gas barrier films, which have high gas barrier properties but low flexibility, or sufficient flexibility but high gas barrier properties. An object of the present invention is to provide a production method for producing a gas barrier film capable of realizing a high gas barrier property and at the same time ensuring a flexibility equivalent to that of a conventional one, and a production apparatus capable of realizing the production method.

In order to solve the above-mentioned problems, a manufacturing method according to claim 1 of the present invention is a method for manufacturing a gas barrier film in which a gas barrier film is formed on a plastic film as a substrate by a plasma chemical vapor deposition (plasma CVD) apparatus. The plasma CVD apparatus introduces at least a reaction chamber for performing plasma CVD, a vacuum means for evacuating the reaction chamber, and a source gas while using a carrier gas in the reaction chamber. Gas supply means, electric field generating means for applying a high-frequency electric field in the reaction chamber, and film conveying means for conveying the plastic film in the reaction chamber, the electric field generating means, A power supply electrode disposed between the plastic film and a ground electrode, wherein the power supply electrode includes the plastic film; The ground electrode is arranged so that the distance between the ground electrode and the surface of the plastic film and the distance between the power supply electrode gradually approach each other along the direction of transport of the plastic film. And forming a gas barrier film on the plastic film by applying an electric field between a power supply electrode and a ground electrode of the electric field generating means using the plasma CVD apparatus .

A manufacturing method according to claim 2 of the present invention is the method for manufacturing a gas barrier film according to claim 1 , wherein the density of the gas barrier film formed on the plastic film is the smallest on the surface side of the plastic film, It is characterized by increasing sequentially in the thickness direction .

A manufacturing apparatus according to a third aspect of the present invention is a gas barrier film manufacturing apparatus for forming a gas barrier film on a plastic film as a substrate by a plasma chemical vapor deposition (plasma CVD) method. A reaction chamber to be executed, a vacuum means for making the inside of the reaction chamber a vacuum state, a gas supply means for introducing a source gas into the reaction chamber while using a carrier gas, and a high frequency in the reaction chamber An electric field generating means for applying the electric field, and a film conveying means for conveying the plastic film in the reaction chamber, wherein the electric field generating means includes a feeding electrode and a ground electrode arranged with the plastic film interposed therebetween. The power supply electrode is disposed at a substantially constant interval with respect to the surface of the plastic film, and the ground electrode is Distance between the distance and the feeding electrode and the surface of the plastic film, the plastic film in the conveyance direction be arranged so as to close progressively in, characterized by.

A manufacturing apparatus according to a fourth aspect of the present invention is the manufacturing apparatus for a gas barrier film according to the third aspect, wherein the feeding electrode has a flat plate shape .

A manufacturing apparatus according to a fifth aspect of the present invention is the gas barrier film manufacturing apparatus according to the third aspect, wherein the power supply electrode is cylindrical .

  As described above, if the method for producing a gas barrier film according to the invention of the present application, in short, a high-frequency electric field is applied to collide electrons with the raw material gas to make the raw material gas into plasma, which is used as a base material for the transparent plastic film When forming a thin film by stacking on the surface, it is installed on both sides where such transparent plastic is conveyed, against the plane of the transparent plastic film where the supply electrode and ground electrode for applying a high frequency electric field are conveyed Since the gas barrier film obtained by this manufacturing method has a high density, i.e., it is hard and brittle, the gas barrier film obtained by this production method is not hard and parallel. Although it has a high gas barrier property, it lacks flexibility, while the opposite is true, in order to ensure flexibility. Although only a thin film with a low density is laminated, flexibility is provided, but the gas barrier property is not so high. On the other hand, while maintaining high gas barrier property, the flexibility of the transparent plastic film is also to some extent It can be ensured. In addition, silicon oxynitride (SiOxCy) is used as a gas barrier layer for imparting gas barrier properties, and at the same time, any of argon, oxygen, or hydrogen is used as a starting material in order to form such a gas barrier layer. If a mixed gas is used at the same time, it is possible to avoid the generation of a large amount of toxic cyanide.

  Embodiments of the present invention will be described below. The embodiment shown here is merely an example, and is not necessarily limited to this embodiment.

(Embodiment 1)
A manufacturing method for manufacturing a gas barrier film, which is a film having a gas barrier property that does not allow gas such as oxygen and water vapor, to permeate a plastic film as a base material according to the present invention by plasma chemical vapor deposition (plasma CVD method) (Hereinafter, it is also simply referred to as “manufacturing method”) and a manufacturing apparatus for carrying out the manufacturing method will be described as a first embodiment with reference to the drawings.

First, the entire manufacturing method according to the present embodiment will be described. At least in the reaction chamber in which the manufacturing method is performed, the manufacturing method provides a vacuum means for making the inside a vacuum state, and provides gas barrier properties to the inside of the reaction chamber. A method comprising: a gas supply means for introducing a raw material gas to perform; an electric field generating means for applying a high-frequency electric field in the reaction chamber; and a film conveying means for conveying the plastic film in the reaction chamber It is. At the same time, the electric field generating means uses a feeding electrode (cathode) and a ground electrode (anode).

  In the following, description will be made with reference to FIGS. 1 and 2 showing the concept of the apparatus for further carrying out the present embodiment.

First, the reaction chamber 12 is necessary to carry out the manufacturing method according to the present embodiment, which is also referred to as a vacuum chamber. In the plasma CVD method to which the manufacturing method according to the present embodiment belongs in the first place, Of course, the reaction chamber 12 may be a general reaction chamber required for a conventionally known plasma CVD method. For reasons described later, the inner wall surface of the reaction chamber 12 in this manufacturing method is, for example, insulated. It is preferable that the body is covered with an insulation treatment such as being entirely covered. In the following description, the reaction chamber 12 is assumed to be insulated. Further, all the means described further below are basically carried out in the reaction chamber 12, or even if they are prepared outside the reaction chamber 12, they actually act in the reaction chamber 12. I refuse to do that.

First, the vacuum means in the present embodiment will be described. This is a means for evacuating the inside of the reaction chamber 12, and in order to improve the reactivity when performing the plasma CVD method, the atmosphere around the reaction is vacuumed as much as possible. It can be said that it is a necessary means because it is preferable to set the state. This vacuum means brings the reaction chamber into a substantially vacuum state, but in this embodiment, an exhaust pump 9 is provided in order to implement such means . The exhaust pump 9 may be a conventionally known one, and further detailed description thereof will be omitted here.

Although then a gas supply means for introducing a raw material gas for imparting reaction chamber 12 inside the gas barrier properties, which also means for implementing the in and apparatus used to implement the conventional plasma CVD method In order to realize such means , for example, as shown in FIG. 1, the carrier gas is passed from the carrier gas cylinder 6 through the mass flow controller 5 and simultaneously the monomer raw material 8 is passed through the liquid mass flow controller 7 and mixed. Then, the gas is discharged into the reaction chamber 12 through the gas pipe 10.

That is, the monomer raw material 8 is released into the reaction chamber 12 by the carrier gas by the gas supply means , but this monomer raw material 8 becomes a raw material for imparting gas barrier properties to the plastic film as the base material. .

  As the monomer raw material 8, conventionally known materials may be used. For example, silicon oxide carbide or silicon oxide is widely used. In this embodiment, alkoxysilane is used. The carrier gas serves to carry the monomer raw material 8 into the reaction chamber 12 as described above. This carrier gas may also be a conventionally known one, for example, argon, oxygen, nitrogen or the like alone or Any of these may be used as a mixture, and oxygen is used in this embodiment. When the plasma treatment is performed using alkoxysilane and oxygen in this manner, SiOxCy (silicon oxide carbide) is deposited on the base plastic film to form a SiOxCy layer that exhibits gas barrier properties. In this regard, the conventional manufacturing method for forming a SiCxNy (silicon carbonitride) film may generate toxic cyan, which is suitable for mass production even if a highly functional gas barrier film is obtained. However, it can be said that such a risk can be eliminated by the manufacturing method according to the present embodiment in which the above-described SiOxCy film is deposited and used as a layer. The thickness of the gas barrier film in the present embodiment is preferably 100 nm or more and 3000 nm or less. However, if the thickness is less than 100 nm, the layer cannot exhibit sufficient gas barrier properties even if SiOxCy is laminated. This is because if the thickness exceeds 3000 nm, the thickness of the entire gas barrier film obtained is unnecessarily thick.

Also , the plastic film as the base material is transported by the film transporting means , and a device for realizing this may be a conventionally known device, that is, the base plastic film is transported from the unwinding 3 and variously on the way. Thus, the above-described process is performed and the sheet is wound on the winding 4.

In the manufacturing method according to the present embodiment, in the reaction chamber 12 in which the chamber is insulated, the reaction chamber is first brought into a substantially vacuum state by vacuum means , and the film is conveyed in the reaction chamber 12 in the substantially vacuum state. The plastic film as the base material is transported by the means, and in the process of transporting the base plastic film, the surface of the base plastic film is exposed to the electric field generated by the electric field generating means composed of the cathode and the anode, and at the same time the gas supply monomer material for imparting gas barrier properties is released into the reaction chamber is substantially vacuum state by means and plasma by released monomers electric field generating means, and by plasma monomers are deposited on a substrate a plastic film surface Layer, this layer functions as a gas barrier layer, and To gas barrier film is obtained, it is a process called. In addition, a conventionally known device group is installed in order to enable this process in the present embodiment.

The manufacturing method according to this embodiment is as described above. However, in this embodiment, the method of generating an electric field in the electric field generating means is different from the manufacturing method by the conventional plasma CVD method. I will explain.

In the conventional electric field generating means , it was important that the surface of the anode was parallel to the surface of the base plastic film being transported by the film transport means . This is because the electric field applied to the base plastic film surface is always uniform. This is because it is necessary that the plasma monomer is laminated on the base plastic film because the electric field is uniform. In other words, by uniformly laminating the monomers, the density of the laminating is the same or nearly the same regardless of which part is taken out. Therefore, by uniformly laminating the monomers for imparting gas barrier properties, the gas barrier properties are uniform. This is because the properties of the obtained gas barrier film are uniform over the entire film. Or, in the conventional means , it can be said that the condition that the impedance of one or both of the cathode and the anode is the same in any part may be essential. This is because by making the impedance uniform, the generated electric field is the same and uniform in any part as described above.

However, in the present embodiment, as shown in FIG. 1, the surface of the anode 2 is not parallel to the surface of the base plastic film being transported by the film transport means , and the distance between them varies depending on the transport direction of the base plastic film. In addition, an anode is installed.

  For example, in the state shown in FIG. 1, the anode 2 is rising to the right along the transport direction of the base plastic film (from left to right in the figure). That is, as the base plastic film is conveyed, the distance between the base plastic film surface and the anode 2 surface becomes narrower. Thus, as the interval becomes narrower, the electron density generated between the anode 2 and the cathode 1 connected to the power source 11 is inclined.

  And when observing the entire gas barrier film according to the present embodiment obtained by passing the inclined electron density through the base plastic film in this way, the flexibility of the base plastic film is not so much impaired, On the other hand, the gas barrier property of the entire gas barrier film is sufficiently high, that is, when viewed as a whole, a gas barrier film that secures a high gas barrier property as well as flexibility is obtained.

  In the manufacturing method according to the present embodiment, as described above, it is important to gradually incline the electron density with respect to the surface of the base plastic film being transported, but the cathode 1 transports the film as shown in FIG. A configuration that can also be used as a device is also conceivable. That is, it can be said that if the roller for transporting the base plastic film acts as the cathode 1, the entire apparatus can be simplified, which is preferable.

  Furthermore, in any case, in order to reliably apply an electric field to the surface of the substrate plastic film being conveyed, it is naturally necessary to apply the electric field only to the necessary portions, but this is not necessary. This means that an electric field must not be applied to the place, and for this purpose, the entire reaction chamber must be insulated. By applying insulation treatment, an electric field is generated only at the necessary location. As a result, an electric field is applied only to the surface of the substrate plastic film being transported, and the plasma monomer adheres only to the surface of the substrate plastic film. Thus, a gas barrier layer is formed.

  In addition, the gas barrier layer in the present embodiment is the SiOxCy layer as described above, but the film deposited at the position where the distance between the electrodes is farthest from the Si density of the film deposited at the position where the electrode distance is closest. The gas barrier layer is preferably laminated so that the Si density is at least 0.6 times or less. This is because the inclination with such a difference can achieve both sufficient flexibility and high gas burrability.

The above explanation relates to the case where the anode installation method is physically changed. However, although the anode is installed in parallel with the transport direction of the base plastic film as usual, the impedance at the anode is the same as that of the base plastic film. It is conceivable to set it to be inclined along the transport direction. In this case, the same effect can be obtained because the generated electric field is inclined as described above, and the physical installation method of the anode is also inclined. It is also possible to further incline the impedance, but the results obtained are the same in any case, and further details are omitted here.

  Thus, if it is the manufacturing method concerning this Embodiment, or the manufacturing apparatus which implement | achieves this manufacturing method, the gas barrier film obtained can have a high gas barrier property and also a flexibility. The gas barrier film obtained by such a production method or production apparatus can have both flexibility and high bus barrier properties.

It is the figure which showed the outline of the manufacturing apparatus concerning this Embodiment It is the figure which showed the outline of another manufacturing apparatus concerning this Embodiment

1 Cathode (power supply electrode)
2 Anode (ground electrode)
3 Unwinding 4 Rewinding 5 Mass flow controller 6 Carrier gas cylinder 7 Liquid mass flow controller 8 Monomer raw material 9 Exhaust pump 10 Gas pipe 11 Power supply 12 Vacuum reaction chamber

Claims (5)

A gas barrier film manufacturing method for forming a gas barrier film on a plastic film as a substrate by a plasma enhanced chemical vapor deposition (plasma CVD) apparatus,
The plasma CVD apparatus includes at least a reaction chamber for performing plasma CVD, a vacuum means for making the inside of the reaction chamber a vacuum state, and a gas for introducing a source gas into the reaction chamber while using a carrier gas A supply means; an electric field generating means for applying a high-frequency electric field in the reaction chamber; and a film conveying means for conveying the plastic film in the reaction chamber,
The electric field generating means has a feeding electrode and a ground electrode arranged with the plastic film interposed therebetween, and the feeding electrode is arranged at a substantially constant interval with respect to the surface of the plastic film. The distance between the plastic film surface and the power supply electrode is arranged so as to gradually approach along the transport direction of the plastic film,
Using the plasma CVD apparatus, applying an electric field between a power supply electrode and a ground electrode of the electric field generating means to form a gas barrier film on the plastic film;
A method for producing a gas barrier film, characterized in that It is a manufacturing method of the gas barrier film according to claim 1,
The density of the gas barrier film to be formed on the plastic film is the smallest on the surface side of the plastic film, and the density of the gas barrier film increases sequentially in the thickness direction of the film,
A method for producing a gas barrier film, characterized in that An apparatus for producing a gas barrier film that forms a gas barrier film on a plastic film as a substrate by plasma enhanced chemical vapor deposition (plasma CVD),
At least a reaction chamber for performing plasma CVD, a vacuum means for evacuating the inside of the reaction chamber, a gas supply means for introducing a source gas into the reaction chamber using a carrier gas, and the reaction An electric field generating means for applying a high-frequency electric field in the chamber, and a film conveying means for conveying the plastic film in the reaction chamber,
The electric field generating means has a feeding electrode and a ground electrode arranged with the plastic film interposed therebetween, and the feeding electrode is arranged at a substantially constant interval with respect to the surface of the plastic film. The distance between the surface of the plastic film and the distance between the feeding electrode and the feeding electrode are arranged so as to gradually approach each other along the transport direction of the plastic film,
An apparatus for producing a gas barrier film. An apparatus for producing a gas barrier film according to claim 3,
The power supply electrode is a flat plate,
An apparatus for producing a gas barrier film. An apparatus for producing a gas barrier film according to claim 3,
The feeding electrode is cylindrical,
An apparatus for producing a gas barrier film.

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