JPH06108230A - Metal oxide-evaporated film and its production - Google Patents

Abstract

PURPOSE:To provide the process for production of the metal oxide-evaporated film which does not curl a base material, has a better gas barrier property and hardly deteriorates the film by handling, etc., even when the large-area base material film is used. CONSTITUTION:The metal oxide evaporated by heating is passed through a plasma space consisting of gases contg. gaseous aliphat. hydrocarbon including fluorine (for example, fluorocarbons) and is then stuck on the base material film in the process for production of the metal oxide-evaporated film by continuously forming the thin film of the metal oxide on at least one surface on the base material film within a vacuum system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal oxide vapor-deposited film and a method for producing the same. More specifically, the present invention provides a more excellent vapor deposition film formation method against vapor, a vapor deposition film thereof, a metal oxide vapor deposition film having a metal oxide vapor deposition film that does not cause a curl phenomenon of a base film, and a method for producing the same. Is.

[0002]

2. Description of the Related Art Vapor-deposited films obtained by forming a vapor-deposited film of a metal oxide on a base film made of a polymer are well known, and because of their transparency and excellent gas barrier properties, It is being used as a packaging material in a wide range of fields including food (USP 344268).
6, JP-B-51-48511, JP-B-63-2485
No. 11, Japanese Patent Publication No. 2-15382, etc.).

[0003]

However, the stress of vapor-deposited films of various metal oxides obtained by vacuum vapor deposition is largely distributed within the film and at the interface with the base film, and as a result, the stress of the base film is increased. Deformation causes mechanical stress, etc. on the vapor-deposited film due to handling during printing, coating, laminating, etc. as post-processing, resulting in poor adhesion and deterioration of gas barrier property due to film cracking. I was left with a problem.

Therefore, the present invention does not cause the curl of the substrate even when a large-area substrate film is used, and
It is an object of the present invention to provide a method for producing a metal oxide vapor-deposited film, which has a better gas barrier property and is less likely to deteriorate due to handling and the like.

[0005]

In order to achieve this object, the invention according to claim 1 is a metal oxide vapor deposition method for continuously forming a metal oxide thin film on at least one surface of a substrate film in a vacuum system. In the method for producing a film, the vaporized metal oxide is deposited on a substrate film after passing through a plasma space consisting of a gas containing an aliphatic hydrocarbon gas containing at least fluorine. A method for manufacturing a film is provided.

The invention according to claim 2 is based on the invention according to claim 1, wherein the aliphatic hydrocarbon gas containing fluorine is a fluorocarbon, and a method for producing a metal oxide vapor-deposited film. Is.

Further, the invention according to claim 3 is a metal oxide vapor-deposited film in which a magnesium oxide thin film is formed on at least one surface of a base film, wherein the magnesium oxide thin film further contains F and C. It is a metal oxide vapor deposition film.

According to a fourth aspect of the present invention, in a metal oxide vapor deposition film in which a silicon oxide thin film is formed on at least one surface of a base film, the silicon oxide thin film further contains F and C.
It is a metal oxide vapor deposition film characterized by containing.

[0009]

According to the present invention, carbon and fluorine atoms in the aliphatic hydrocarbon gas containing fluorine used in the film formation process are incorporated into the vapor deposition film, and the energy of plasma is measured to result in the film formation. It is possible to produce a metal oxide vapor-deposited film that can be modified in the porous part, has a particularly high barrier property against water vapor, and does not cause deformation of the film.

In particular, a metal oxide vapor-deposited film in which magnesium oxide or silicon oxide is used as a metal oxide and F and C are incorporated does not cause curling, is excellent in gas barrier property, and is formed by handling or the like. It does not easily deteriorate.

The present invention will be described in detail below. The substrate film according to the present invention is a support for a vapor-deposited film, and a polymer film excellent in dimensional stability and mechanical strength is suitable.

For example, polyethylene, polypropylene,
Polyolefin such as polybutene; polystyrene; polyethylene terephthalate, polybutylene terephthalate,
Polyester such as polyethylene-2,6-naphthalate; Nylon-6, Nylon-11, aromatic polyamide; Polycarbonate; Polyvinyl chloride, polyvinylidene chloride; Films such as polyimide, or copolymers of monomers constituting these, or others It may be a copolymer with the above monomer.

Further, the base film may contain known additives such as antistatic agents, ultraviolet absorbers, plasticizers, lubricants, colorants and the like.

The substrate film is preferably a film stretched in the longitudinal and transverse directions from the viewpoint of strength, dimensional stability and heat resistance.

The thickness of the base film is not particularly limited, but a film having a thickness of 3 to 400 μm can be used from the viewpoint of strength. From the viewpoint of printing and laminating processability, the range of 6 to 200 μm is preferable.

The metal oxide thin film according to the present invention is an oxide selected from magnesium, silicon, aluminum, titanium, tin, zinc and the like, and is preferably an oxide of magnesium or silicon. Further, it may be a mixed layer of two or more kinds selected from the above.

As a heating method of the oxide material for forming the metal oxide thin film according to the present invention, a known electron beam heating method can be used. In particular, a large self-pierce type electron gun or the like can be used in order to obtain high-speed evaporation of several thousands to 10,000 liters / second. However, depending on the material, resistance heating or induction heating is also possible.

The vacuum system according to the present invention is 10 ^-3 to 10 ^-6.
The degree of vacuum is good at about Torr, and by exhausting with a pump exhaust system provided in a known vacuum vapor deposition machine,
The inside can be maintained at this vacuum degree.

It is a necessary condition that the plasma space according to the present invention comprises a gas containing an aliphatic hydrocarbon gas containing at least fluorine atoms.

For example, CCl ₃ F (CFC 11), CC
l ₂ F ₂ (CFC 12), CF ₃ Cl (CFC 13),
CF ₄ (Freon 14), CClF ₂ CClF ₂ (CFC 22), CCl ₂ FCClF ₂ (CFC 113), CC
lF ₂ CClF ₂ is fluorocarbons (Freon 114) or the like, argon, an inert gas may also contain 5～95VOL% above fluorocarbons such as xenon.

The electrode for exciting the gas is a coil-shaped electrode formed by forming a linear electrode made of metal such as stainless steel or copper into a spiral shape; a parallel plate electrode using a plate-shaped electrode, etc. Any shape can be used.

That is, an electrode connected to a high frequency power source and a gas introducing pipe for introducing a plasma generating gas are arranged near the electrode in a vacuum closed system, and the gas is continuously introduced from the gas introducing pipe to the vicinity of the electrode. However, high frequency power may be supplied to the electrodes.

The plasma according to the present invention is not limited to the above-mentioned commercial high frequency plasma having a frequency of 13.56 MHz, and is obtained by introducing a gas containing an aliphatic hydrocarbon containing at least fluorine atoms into a vacuum closed system. Since it is meaningful to utilize the plasma space provided in the film forming process, a plasma space obtained by applying power to a desired electrode by, for example, microwaves in the frequency band 2450 MHz, direct current, alternating current, or a combination thereof. It doesn't matter if you have it. As a matter of course, a magnetic field may be used together to improve the plasma density.

For example, when high frequency power of 13.56 MHz is used, the optimum conditions differ depending on parameters such as power supply, electrode shape, positional relationship between the base material film and the electrodes, film forming conditions, etc. The value obtained by dividing the supplied power in the plasma space is in the range of 0.16 to 9.4 W / cm ³ , and preferably 0.31 to 4.7 W / cm ³ .

When the supplied power becomes 9.4 W / cm ³ or more, the electron temperature in the plasma rises and the plasma is more activated, but the heat load on the base film increases,
The chargeability of the base film, which is an insulator, increases,
On the contrary, the deposited film itself may deteriorate. Also, 0.16
If it is W / cm ³ or less, the power density is too low and the film quality is not sufficiently stable.

The vaporized metal oxide passes through the plasma space and adheres to the base film. For this reason, the metal oxide vapor deposition source needs to be positioned below the coil-shaped, parallel plate type electrodes, and the base film needs to be positioned above the electrodes.

When the base film has a strip shape, a conventional cooling roll may be arranged above the electrode and the base film may be run while being held by the cooling roll.

In order to prevent the base film from being charged by plasma or a metal oxide passing through the plasma space and adhering to the base film, a metal member that comes into contact with the base film on the surface of the cooling roll should be provided and grounded. Is desirable.

The metal oxide thin film formed on the substrate film obtained by the manufacturing method of the present invention forms plasmas of fluorine, carbon, etc. as described above in addition to the constituent elements of the metal oxide material. The feature is that the constituent elements are incorporated in the vapor deposition film.

The implantation of these small atoms such as fluorine and carbon has the purpose of reducing the residual stress generated at the interface between the substrate film and various metal oxide vapor deposition films and in the vapor deposition film. For example, in the case of magnesium oxide, , Carbon and fluorine atoms are 4 to 1 each, compared with the conventional vacuum deposition method.
It is mixed in an amount of 5, 3 to 5 Atomic%, and is incorporated in the main component magnesium oxide in the form of a carbide or a fluoride.

FIG. 1 is an explanatory view showing an embodiment of the present invention.

The structure of the winding chamber A will be described below. After being unwound from the unwinding roll (1) and successively passing through the control roll (2) and the expander roll (3), the cooling roll (4)
It runs while being held by and is wound up again by the winding roll (5).

Next, the structure of the vapor deposition chamber B will be described below. A vapor deposition source (7) for the metal oxide (6) is arranged below the cooling roll (4) and can be heated by an electron gun (8). The cooling roll (4) and the vapor deposition source (7) are arranged with a coiled electrode (9) sandwiched therebetween, and a plasma generating gas introduction port (10) is provided near the electrodes. The vaporized metal oxide (6) vapor passes through the plasma space formed in the vicinity of the coil-shaped electrode, reaches the base film held on the cooling roll, and is formed into a thin film.

Reference numeral (11) is a scanner system for scanning an electron beam (12) generated by an electron gun (8) on the surface of the vapor deposition material two-dimensionally in an XY shape to uniformly heat the material, which are orthogonal to each other. By changing the magnetic field generated by the electromagnet, it is possible to scan in XY.

Reference numeral (13) is a shield plate, and the cooling roll (4) is exposed to the vapor deposition source (7) at a position between the shield plates.
The metal oxide (6) adheres to the surface of the base film (14).

A gas introduction port (10) for plasma generation is arranged near the electrode, and a gas introduction pipe is provided through a mass flow controller (15) for controlling the gas flow rate of an inert gas such as CFCs and argon. It is connected to the.

Regarding the amount of the gases such as CFCs and argon introduced, the degree of vacuum in the system is monitored by a vacuum gauge (16) provided in the vapor deposition chamber, and a stable degree of vacuum is obtained by the mass flow controller. Can be controlled.

In order to produce a vapor-deposited film using this apparatus, first, the inside of the apparatus is evacuated by the exhaust system,
After being in a vacuum state of 10 ⁻⁵ to 10 ⁻⁶ Torr, a gas containing a CFCs gas was introduced from the gas inlet while adjusting the flow rate by a mass flow controller, and at the same time, high frequency power was supplied to the coiled electrode for plasma. And the metal oxide is vaporized by heating the vapor deposition source while running the substrate film at a predetermined speed.

The vapor-deposited film thus obtained contains 4 to 15 and 3 to 5 Atomic% of carbon and fluorine atoms, respectively, in addition to the elements constituting the original vapor deposition material, and can be vaporized at high speed. The porous part of the formed metal oxide thin film is densified in the form of carbide or fluoride.

[0040]

【Example】

 [Example 1]

(A) Device Device of FIG. 1 (B) Ultimate vacuum 1.0 × 10 ^-5 Torr (C) Base film (a) Material Biaxially stretched polyethylene terephthalate (b) Thickness 12 μm (D) Cooling roll Temperature -20 ° C (E) Vapor deposition source (a) Distance from cooling roll 300 mm (b) Metal oxide magnesium oxide (c) Heating source Electron gun (accelerating voltage 30 kV emission current 10 A) (F) Plasma (a) Gas CF ₄ 100% (b) Flow rate Adjusted by mass flow controller so that chamber A in the equipment is 1.1 × 10 ^-4 Torr. (C) Supply power High frequency (13.56MHz 2kW)

Under the above conditions, the vapor deposition rate is 5000Å /
The substrate film was run at a speed of 1.6 m / sec for 2 seconds to continuously coat the vapor deposition film. The thickness of the obtained vapor deposition film was measured by a fluorescent X-ray analysis method and found to be 549Å.

This vapor-deposited film was sampled every 100 m in the length direction, and the composition was analyzed by X-ray photoelectron spectroscopy (ESCA). The results are shown in Table 1.

The films obtained from Table 1 are Mg, O, C and F
And C and F were included in 5.3, 2.1 Atomic%.

Further, when the degree of curl of the vapor deposition film sampled at 10 * 10 mm was visually evaluated in 5 steps, it was ranked 1 and there was no curl at all.

Further, an unstretched polypropylene film 60 μm and a laminated film were prepared from this vapor-deposited film using a two-component curing type polyurethane adhesive, and the oxygen permeability and the water vapor vapor permeability of this laminated film were measured.
1.62 cc / m ² / day / atm, 0.1 respectively
It was 8 cc / m ² / day / atm, and particularly, the barrier property against water vapor was excellent. The results are shown in Table 1.

[Examples 2 to 4] The line speed was changed under the same conditions as in Example 1. When the vapor-deposited film thickness was similarly measured, it was 300Å, 650Å, 1100Å. The results are shown in Table 1.

In each of Examples 2 to 4, there was no curl, and there was almost no film thickness dependency of oxygen and water vapor transmission rates, and all showed good results.

[Comparative Examples 1 to 3] The same procedure as in Example 1 except that no plasma was generated, and the film feed speed was changed to 3
Different levels of vapor deposition thickness were obtained. Deposition thickness is 619
It was Å, 850Å, 1100Å. Each water vapor permeability of there about 2 times or more compared with and embodiment where 0.5,0.45,0.44g / m ² / 24h, was less good value even by increasing the deposition film thickness. The results are shown in Table 1. Also,
Regarding the curl, it was ranked 4 to 5 and was extremely curled.

[Comparative Examples 4 to 5] The same tests as in Example 1 were carried out using argon and oxygen as the plasma gas. The results are shown in Table 1.

From the above, when the plasma obtained from argon and oxygen gas was used, the water vapor transmission rate was
0.40, 0.39 g / m ² / day, Example 1
It was insufficient about twice as much as

Example 5 Silicon oxide was used as the metal oxide material, and the same test as in Example 1 was conducted under the following plasma conditions.

Plasma (a) Gas CF ₄ -Ar (80-20 VOL%) (b) Flow rate Adjusted with mass flow controller so that chamber A in the apparatus is 1.0 × 10 ^-3 Torr (c) Supply power High frequency (13.56MHz, 3kW)

Under the above conditions, the deposition rate is 7,000Å /
Second, the substrate film was run at a speed of 2.0 m / sec, and the same evaluation as in Example 1 was performed. The results are shown in Table 1.

From Table 1, the obtained films are Si, O, C, F
And C and F were contained in 4.2, 2.3 Atomic%. Oxygen and water vapor transmission rate is 1.3 cc / m ² /
It was day / atom, 0.30 g / m ² / day.

[Comparative Examples 6 to 11] Similar to Example 5, the vapor deposition film thickness was obtained when silicon oxide was used as the evaporation material and plasma was not used in the film forming process, and when argon and oxygen were used as the plasma gas. Was tested by changing the three levels. The results are shown in Table 1.

[0057]

[Table 1]

Curl evaluation: No curl Rank 1 ← → Large curl Rank 5 Oxygen permeability (cc / m ² / day / atm) 25 ° C.-
75% RH water vapor transmission rate (g / m ² / day)

As described above, the vapor deposition film obtained by the specific method according to the present invention contains fluorine used in the film formation process, unlike the vapor deposition film obtained by the conventional method (see FIG. 2 (a)). Carbon and fluorine atoms in the aliphatic hydrocarbon gas are taken into the vapor-deposited film (see Fig. 2 (b)), and the energy of the plasma is measured. As a result, the porous part of the film can be modified, especially An extremely high barrier property against water vapor was obtained, and a vapor-deposited film that did not cause deformation of the film was obtained.

[0060]

As described above, according to the present invention, even a porous metal oxide thin film formed by rapid evaporation is composed of an aliphatic hydrocarbon gas containing at least a specific fluorine atom during film formation. By forming and utilizing a plasma space containing active fluorine, carbon radicals and ions, carbonization with vapor deposition particles,
By enhancing the fluorination reaction and allowing the presence of carbides and fluorides as a thin film structure, an extremely excellent barrier property against water vapor could be achieved. This is because not only the membrane structure was densified by plasma,
It is believed that the film is coated with fluoride, resulting in a vapor-deposited film having a high barrier property.

Further, such a vapor-deposited film can be put to practical use in a wide range of fields including packaging materials by printing, laminating and the like.

[0062]

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a main part of an apparatus according to the present invention.

FIG. 2 is an explanatory view showing a conventional vapor deposition film structure and the vapor deposition film film structure of the present invention.

[Explanation of symbols]

 1 Unwinding Roll 2 Control Roll 3 Expander Roll 4 Cooling Roll 5 Winding Roll 6 Metal Oxide 7 Evaporation Source 8 Electron Gun 9 Coiled Electrode 10 Plasma Generation Gas Inlet 11 Scanner System 12 Electron Beam 13 Shielding Plate 14 Base Material Film 15 Mass flow controller 16 Vacuum gauge

Claims (4)

[Claims] 1. A method for producing a metal oxide vapor-deposited film in which a metal oxide thin film is continuously formed on at least one surface of a base material film in a vacuum system, wherein the heated and vaporized metal oxide is a fat containing at least fluorine. A method for producing a metal oxide vapor-deposited film, which comprises adhering to a substrate film after passing through a plasma space made of a gas containing a group hydrocarbon gas. 2. The method for producing a metal oxide vapor deposition film according to claim 1, wherein the aliphatic hydrocarbon gas containing fluorine is a fluorocarbon. 3. A metal oxide vapor deposition film in which a magnesium oxide thin film is formed on at least one surface of a base film, wherein the magnesium oxide thin film further contains F and C. 4. A metal oxide vapor deposition film in which a silicon oxide thin film is formed on at least one surface of a base film, wherein the silicon oxide thin film further contains F and C.