JP4424033B2 - Deposition film by plasma CVD method - Google Patents

Description

The present invention relates to a deposited film formed on the surface of a plastic bottle by a plasma CVD method.

  Conventionally, in order to improve the characteristics of various substrates, a deposited film is formed on the surface by a plasma CVD method. For example, in the field of packaging materials, it is known to improve a gas barrier property by forming a deposited film on a plastic substrate such as a container by a plasma CVD method.

  For example, at least one or two or more of silicon oxide, carbon, hydrogen, silicon and oxygen are formed on at least one side of a plastic container by plasma CVD using at least an organic silicon compound and a gas having oxygen or oxidizing power. A method for producing a plastic container is known in which the concentration of an organosilicon compound changes when a barrier layer (deposited film) containing at least one compound composed of the above elements is formed (see Patent Document 1). ).

And a base material, a gas barrier layer made of a vapor-deposited film formed on one or both sides of the base material, and a water-repellent layer made of a water-repellent film formed on the gas barrier layer. A characteristic gas barrier film is also known (see Patent Document 2).
JP 2000-255579 A (Claims) JP 2003-53873 A (Claims)

  However, for example, a vapor deposition film formed by the method of Patent Document 1 has excellent barrier effect against various gases such as oxygen, but has high moisture permeability, and moisture penetrates into the film. There is a drawback in that the barrier property is lowered, and the improvement is demanded particularly in the field of packaging materials. In addition, the gas barrier film described in Patent Document 2 is a vapor-deposited film although water permeability is improved because a water-repellent layer is formed on the surface of the gas barrier layer, which is a vapor-deposited film. Since the water-repellent layer is formed as a completely separate layer from the gas barrier layer, peeling or the like is likely to occur between the gas barrier layer and the water-repellent layer, and there is a problem in durability, impeding its practical use. This is the current situation.

  Accordingly, an object of the present invention is to provide a deposited film formed by a plasma CVD method which is free from problems such as peeling and has excellent durability and a barrier effect against moisture.

According to the present invention, in the deposited film formed on the surface of the plastic bottle by the plasma CVD method using the organometallic compound and the oxidizing gas as the reaction gas,
The vapor-deposited film has an adhesive layer region located on the surface of the plastic bottle, a barrier layer region located on the adhesive layer region, and an outer surface protective layer region located on the surface of the barrier layer region. And
The adhesion layer region has a (M + O) concentration lower than the barrier layer region and (C) on the basis of the three elements based on the metal element (M), oxygen (O) and carbon (C) derived from the organometallic compound. The barrier layer region has a (M + O) concentration higher than that of the outer surface protective layer region, and the (M + O) concentration at the interface between the barrier layer region and the outer surface protective layer region. Is substantially continuously changed, and the outer surface protective layer region has a (C) concentration of 15 element% or more.
According to the present invention, there is also provided a plastic bottle in which the deposited film is formed on the inner surface.

In the deposited film of the present invention,
1. In the barrier layer region, from the viewpoint of transparency and gas barrier properties, the element ratio (M / O) is in the range of 1.8 to 2.4,
2. The organometallic compound is an organosilicon compound and the metal (M) is silicon (Si);
Is preferred.

  In the deposited film formed by the plasma CVD method of the present invention, the barrier layer region and the outer surface protective layer region located on the barrier layer region surface are integrally formed without being partitioned at the interface, and therefore, delamination between layers is performed. It does not occur, is excellent in durability, and the outer surface protective layer region on the surface is excellent in moisture barrier properties, so that deterioration of gas barrier properties due to moisture penetration is effectively prevented.

The deposited film of the present invention is formed on the surface of a plastic bottle (hereinafter sometimes simply referred to as a substrate or a substrate) by plasma CVD using an organometallic compound and an oxidizing gas as reaction gases. The deposited film has a barrier layer region located on the substrate side according to the element concentration represented by the three-element standard of metal element (M), oxygen (O) and carbon (C) derived from the organometallic compound, It is divided into an outer surface protective layer region on the barrier layer region, and preferably an adhesive layer region is further formed between the barrier layer region and the substrate surface.

  Please refer to FIG. 1 of the accompanying drawings. FIG. 1 schematically shows the elemental composition (M, O, C) of the vapor deposition film of the present invention measured by X-ray photoelectron spectroscopy, and this vapor deposition film is directed from the outer surface side toward the substrate surface. The outer surface protective layer region X, the gas barrier layer region Y, and the adhesive layer region Z are divided into three regions.

  In FIG. 1, the outer surface protective layer region X located on the outer surface of the deposited film is a region having a (C) concentration of 15 element% or more, and has a large amount of carbon and is rich in organicity. Therefore, since a region rich in organicity is formed on the surface, the deposited film of the present invention is excellent in moisture barrier properties (barrier properties). For example, when the (C) concentration is less than 15 element%, the amount of oxygen atoms (O) or OH groups present in the surface region is large, and as a result, the surface of the deposited film is rich in hydrophilicity. As a result, the barrier property against moisture decreases, moisture penetrates into the film, and the gas barrier property decreases. The (C) concentration in the outer surface protective layer region X is more preferably 22 element% or more, and preferably 40 element% or more.

The gas barrier layer region Y is a region having a (C) concentration of less than 5 element% and a (M + O) concentration higher than that of the outer surface protective layer region X. That is, this region Y formed in the central portion of the deposited film is a layer having low organicity and rich in inorganicity, and particularly has a high barrier property against oxygen. For example, when an organosilicon compound such as hexamethyldisiloxane (HMDSO) is used as the organometallic compound, the gas barrier layer region is mainly composed of silicon oxide. Therefore, the deposited film of the present invention is particularly useful in the field of packaging materials to which plastic bottles that require barrier properties against gases such as oxygen and carbon dioxide are applied .

Further , the adhesive layer region Z formed between the gas barrier layer region Y and the substrate surface is a region having a (C) concentration of 20 element% or more, and this region is also highly organic. That is, the gas barrier layer region Y is highly inorganic, has a high oxygen barrier property, has low flexibility , and lacks adhesion to the substrate. However, the highly organic adhesive layer region has high flexibility and good adhesion to the plastic forming the substrate . Therefore, by forming the gas barrier layer region Y on the substrate surface (plastic bottle surface) with the highly organic adhesive layer region Z interposed therebetween, it is possible to effectively avoid a decrease in adhesiveness.

  In the present invention, as understood from FIG. 1, the (M + O) concentration changes substantially continuously at the interface portion between the barrier layer region Y and the outer surface protective layer region X, and the barrier layer region Y It is also an important feature that the (M + O) concentration changes substantially continuously also at the interface portion between the adhesive layer region Z and the adhesive layer region Z. That is, at these interface portions, the (M + O) concentration continuously monotonously decreases or increases. This is because the regions X, Y, and Z are integrally formed, and between the adjacent regions. It means that a clear interface is not formed. Therefore, the vapor deposition film of the present invention does not cause separation between the regions, is extremely excellent in durability, and exhibits stable barrier properties over a long period of time against gases such as oxygen and moisture. .

  As described above, in the present invention, the outer surface protective layer region X, the barrier layer region Y, and the adhesive layer region Z are not present in the form of clear layers, and there is no clear interface between the layers. . Therefore, although the thickness of each region cannot be critically defined, the thickness of the deposited film (total thickness of each region) is usually in the range of 4 to 500 nm, and exhibits a sufficient barrier property against moisture. The outer surface protective layer region X is preferably formed to a depth of 0.2 nm or more from the surface, and the gas barrier layer region Y has a thickness of approximately 4.0 nm or more. It is preferable that the adhesive layer region Z has a thickness of approximately 0.2 nm or more.

  In the present invention, in order to further improve the barrier property against moisture, it is preferable to form the surface of the outer surface protective layer region X as a rough surface. For example, by adjusting the average surface roughness Ra (JIS B0601) to about 0.1 to 10.0 nm, the barrier property against moisture can be further enhanced. Such a rough surface can be formed, for example, by adjusting the degree of pressure reduction for glow discharge and forming glow discharge under a relatively high pressure when forming a deposited film.

[ Plastic bottle ]
In the present invention, as the plastic forming the plastic bottle (substrate) on which the above-mentioned vapor deposition film is to be formed, a known thermoplastic resin such as low density polyethylene, high density polyethylene, polypropylene, poly 1-butene, poly 4 is used. -Methyl-1-pentene or polyolefins such as random or block copolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, etc., cyclic olefin copolymers, and ethylene / acetic acid Vinyl copolymer, ethylene / vinyl alcohol copolymer, ethylene / vinyl compound copolymer such as ethylene / vinyl chloride copolymer, polystyrene, acrylonitrile / styrene copolymer, ABS, α-methylstyrene / styrene copolymer Styrenic resin such as polyvinyl chloride Polyvinylidene chloride, polyvinyl chloride / vinylidene chloride copolymer, polyvinyl compounds such as polymethyl acrylate and polymethyl methacrylate, polyamides such as nylon 6, nylon 6-6, nylon 6-10, nylon 11 and nylon 12, polyethylene The resin may be any one of thermoplastic polyesters such as terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polycarbonate, polyphenylene oxide, biodegradable resins such as polylactic acid, and mixtures thereof.

In the present invention, as the plastic bottle, a biaxial stretch blow molded bottle formed from a polyester such as polyethylene terephthalate is particularly suitable.

Further, the plastic bottle may be a gas barrier multilayer structure having the above-mentioned thermoplastic resin (preferably olefin resin) as an inner and outer layer and an oxygen absorbing layer between the inner and outer layers. By forming the deposited film of the present invention on the inner layer and / or outer layer surface of such a multilayer structure, the oxygen barrier property can be remarkably improved.

[Reactive gas]
In the present invention, an organometallic compound and an oxidizing gas are used as a reaction gas. If necessary, a hydrocarbon serving as a carbon source can be used in combination with them.

In the present invention, an organosilicon compound is preferably used as the organometallic compound, but it is not limited to an organosilicon compound as long as it reacts with an oxidizing gas to form a metal oxide, For example, various things, such as organoaluminum compounds, such as a trialkylaluminum, others, an organic titanium compound, can be used. Examples of organosilicon compounds include hexamethyldisilane, vinyltrimethylsilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, phenylsilane, methyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, Organic silane compounds such as tetraethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, etc., organic such as octamethylcyclotetrasiloxane, 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane A siloxane compound or the like is used. In addition to these materials, aminosilane, silazane, and the like can also be used.
The above-mentioned organic metals can be used alone or in combination of two or more. Moreover, silane (SiH ₄ ) or silicon tetrachloride can be used in combination with the above-described organosilicon compound.

Oxygen or NO _x is used as the oxidizing gas, and argon or helium is used as the carrier gas.

Further, as the carbon source, hydrocarbons such as CH ₄ , C ₂ H ₄ , C ₂ H ₆ , C ₃ H ₈ may be used in addition to the organosilicon compound and the organometallic compound.

[Formation of evaporated film]
In the present invention, a deposited film is formed on the surface of the substrate by the plasma CVD method in the atmosphere containing the reaction gas described above.

  Plasma CVD is a method for growing a thin film by using gas plasma. Basically, a gas containing a raw material gas is discharged under a reduced pressure with electric energy by a high electric field, decomposed and generated. It consists of a process in which a substance is deposited on a substrate in the gas phase or through a chemical reaction on the substrate. The plasma state is realized by glow discharge. Depending on the glow discharge method, a method using a direct current glow discharge, a method using a high frequency glow discharge, a method using a microwave discharge, and the like are known. .

Low temperature plasma CVD
a. Because it uses direct decomposition of gas molecules by fast electrons, it can easily dissociate raw material gas with large generation energy.
b. The electron temperature is different from the gas ion temperature, and the electron temperature is a high temperature that has the energy necessary to carry out a chemical reaction, but the ion temperature is in a thermal non-equilibrium state that is a low temperature, enabling a low temperature process.
c. A relatively uniform amorphous film can be formed even when the substrate temperature is low.
It can be easily applied to the formation of a deposited film on a plastic substrate.

  In the present invention, the deposited film must be formed so as to form the region shown in FIG. As such means, for example, there are means such as adjustment with a reactive gas or glow discharge output adjustment.

  When the reaction gas is used, for example, when the supply amount of the oxidizing gas is small as compared with the organometallic compound, the level of oxidative decomposition of the organometallic compound is low and a polymer is formed. As a result, regions with a large amount of carbon, for example, the outer surface protective layer region X and the adhesive layer region Z can be formed. Further, by increasing the supply amount of the oxidizing gas as compared with the organometallic compound, the oxidative decomposition of the organometallic compound proceeds to a high level, so that a nearly complete metal oxide is formed. As a result, a region with a small amount of carbon, that is, a gas barrier layer region Y can be formed. Furthermore, in order to form the outer surface protective layer region X, a hydrocarbon serving as a carbon source can be supplied.

  In addition, when each region X to Z is formed by adjusting the reaction gas, the (M + O) concentration changes continuously, and the balance between the microwave output and the oxygen supply amount is maintained so that no interface is generated between the regions. Must be considered.

  Further, in the case of adjusting the output of glow discharge, for example, if plasma-generated glow discharge is generated at a low output, regions such as the outer surface protective layer region X and the adhesive layer region Z with a large amount of carbon can be formed. When glow discharge is performed at a high output, the gas barrier layer region Y with a small amount of carbon can be formed.

This output change method is based on the following principle.
For example, when an organic silicon oxide is taken as an example, it is considered that a silicon oxide film is formed by an organic silicon compound and an oxidizing gas through the following reaction path.
(a) Extraction of hydrogen: SiCH ₃ → SiCH ₂
(b) Oxidation: SiCH ₂ → SiOH
(c) Dehydration condensation: SiOH → SiO

That is, when glow discharge is performed at a high output, for example, an output of 100 W or more, the organosilicon compound reacts all the way to the stage (c). As a result, the gas barrier layer region Y with a high oxidative decomposition level and a low carbon content. Is formed. On the other hand, when glow discharge is performed at a low output, for example, about 20 to 80 W, a reaction between SiCH ₂ radicals generated in the step (a) occurs, and an organosilicon compound polymer is generated. Many outer surface protective layer regions X and adhesive layer regions Z are formed.
In addition, when each region X to Z is formed by adjusting the output of the glow discharge, the output of the glow discharge is continuously adjusted so that the (M + O) concentration continuously changes and no interface is generated between the regions. It is necessary to change.

  In the present invention, glow discharge for plasma generation is performed by a high-frequency electric field or a microwave electric field. When the substrate to be processed is plastic, when glow discharge is performed in a high-frequency electric field, the optimum conditions differ depending on the distance between the electrodes and cannot be specified in general. Preferably, when glow discharge is performed in a microwave electric field, the glow discharge at high output is preferably 90 W or more.

[Processing equipment]
In the present invention, the apparatus used for forming the vapor deposition film described above includes a plasma processing chamber including a substrate to be processed, an exhaust system for maintaining the plasma processing chamber in a reduced pressure state, and introducing a processing gas into the plasma processing chamber. A gas introduction system for processing and an electromagnetic wave introduction system for generating plasma in the plasma processing chamber. An example of such an apparatus is shown in FIG. 2 by taking a microwave plasma processing apparatus as an example.

  In FIG. 2, the plasma processing chamber denoted by 10 as a whole is composed of an annular base 12, a cylindrical side wall 14, and a canopy 16 that closes the upper portion of the cylindrical side wall 14.

  A first exhaust hole 20 is formed in the central portion of the annular base 12, and an annular recess 22 is formed on the upper surface of the base 12 so as to surround the first exhaust hole 20, Further, an annular groove 24 is formed around the annular recess 22, and the annular groove 24 communicates with the second exhaust hole 26.

  The annular recess 22 accommodates a bottle holder 30 that holds the bottle 28 in an inverted state. As apparent from FIG. 2, the bottle holder 30 is fitted with the neck portion of the bottle 28 in an inverted state, and the neck portion of the bottle 28 held by the holder communicates with the first exhaust hole 20. A gas supply pipe 32 is inserted into the bottle 28 from the one exhaust hole 20 through the neck of the bottle 28.

  The cylindrical side wall 14 is provided with a microwave introduction port 34, and a microwave transmission member 36 such as a waveguide or a coaxial cable is connected to the microwave introduction port 34. That is, a microwave is introduced into the plasma processing chamber 10 from a predetermined microwave oscillator through the microwave transmission member 36.

  The canopy 16 is provided with a cooling gas supply hole 40, whereby the cooling gas is held in an inverted state in the plasma processing chamber 10 after the deposition film is formed or during the deposition film formation. The bottle 28 is sprayed onto the bottom of the bottle 28 for cooling.

  Further, in order to ensure the hermeticity of the plasma processing chamber 10, O-rings 42 are respectively provided at the interface between the base 12 and the cylindrical side wall 14 and at the interface between the cylindrical side wall 14 and the canopy 16. . The bottle holder 30 is also provided with an O-ring 42 for blocking the inside and the outside of the bottle 28.

  Furthermore, a shield 44 for confining microwaves is provided in each of the first exhaust hole 20 and the second exhaust hole 26 formed in the base 12. Moreover, the base 12, the cylindrical side wall 14, and the canopy 16 are all made of metal for microwave confinement.

  In forming a deposited film by plasma treatment, first, the bottle holder 30 holding the bottle 28 in an inverted state is placed on the annular recess 22 of the base 12, and in this state, the base 12 is moved to an appropriate lifting device. And is bonded to the cylindrical side wall 14 to form a plasma processing chamber 10 in which a sealed and inverted bottle 28 is accommodated as shown in FIG.

  Next, the gas supply pipe 32 is inserted into the bottle 28 from the first exhaust hole 20, and the vacuum pump is driven to maintain the inside of the bottle 28 in a vacuum state by exhausting from the first exhaust hole 20. . At this time, in order to prevent the deformation of the bottle 28 due to the external pressure, the inside of the plasma processing chamber 10 outside the bottle 28 is decompressed from the second exhaust hole 26 by a vacuum pump.

  The degree of decompression in the bottle 28 is such that the degree of decompression is high such that glow gas is generated by introducing the processing gas from the gas supply pipe 32 and microwaves, and is particularly suitable, for example, 1 to 500 Pa. Is preferably in the range of 5-50 Pa. On the other hand, the degree of decompression in the plasma processing chamber 10 outside the bottle 28 is such that no glow discharge occurs even when microwaves are introduced.

  After reaching this reduced pressure state, a reactive gas is introduced into the bottle 28 through the gas supply pipe 32, and a microwave is introduced into the plasma processing chamber 10 through the microwave transmission member 36 to generate plasma by glow discharge. The electron temperature in this plasma is tens of thousands of K, the temperature of gas particles is about two orders of magnitude higher than that of several hundred K, and is in a thermally non-equilibrium state, compared to a low-temperature plastic substrate. However, plasma treatment can be performed effectively.

  The microwave output for the above reaction gas or glow discharge is adjusted as described above, and the deposited film is formed in the order of the inner surface of the bottle, the adhesive layer forming region Z, the gas barrier layer region Y, and the outer surface. When the protective layer X is formed and its elemental composition is measured by X-ray photoelectron analysis, it becomes as shown in FIG. In addition, by raising the pressure in the bottle 28 to about 15 to 500 Pa at the last stage, the surface of the outer surface protective layer region can be roughened and the barrier property against moisture can be improved.

  After performing the predetermined plasma processing, the introduction of the processing gas and the introduction of the microwave are stopped, the cooling gas is introduced from the cooling gas supply hole 40, the inside and outside of the bottle 28 are returned to normal pressure, and the plasma is supplied. By taking out the treated bottle 28 out of the plasma processing chamber 10, a plastic bottle on which a target vapor deposition film is formed can be obtained.

  The plasma treatment time differs depending on the inner surface area of the bottle to be treated, the thickness of the thin film to be formed, the kind of the processing gas, and the like. More than one second is necessary for the stability of the plasma treatment, and a reduction in time is required from the viewpoint of cost.

The present invention will be described in the following examples, but the present invention is not limited to the following examples in any way.

1. Composition analysis method in the film The inner surface of the body of the bottle coated with the vapor deposition film on the inner surface of each of silicon, oxygen, and carbon in the depth direction of the film using an X-ray photoelectron spectrometer (Quantum2000) manufactured by PHI Distribution was measured.
The silicon concentration and oxygen concentration were corrected based on fused quartz (SiO ₂ ), and the film thickness was estimated at the same sputtering rate as that of fused quartz (SiO ₂ ) for convenience.

2. Evaluation of moisture barrier In a PET bottle coated with a vapor-deposited film, 500 ml of alkaline ionized water (commercially available alkaline ion pH 8.5) is filled at room temperature, and the bottle mouth is sealed with an aluminum foil laminate with a sealant. Then, after measuring the total weight (M1), the total weight (M2) after 14 days storage in an environment of 40 ° C. and 90% RH is measured, and the water permeation amount of M1-M2 is confirmed to confirm the moisture barrier property. Evaluation was performed.

3. Evaluation of oxygen barrier After removing alkali ion water from the bottle after the moisture barrier measurement, the oxygen transmission rate in an atmosphere of 37 ° C. and 100% RH was measured with an oxygen transmission rate measuring device (OX-TRAN, manufactured by Modern Control). The oxygen barrier was evaluated.

4). Evaluation of adhesion of deposited film A 15mm square test piece was cut out from the body of a PET bottle coated with a deposited film on the inner surface and stored in alkaline ionized water at 70 ° C for 2 days. Then, an X-ray fluorescence analyzer (Rigaku ZSX ) Was used to measure the amount of silicon in the film over time, and the residual rate was used to evaluate the adhesion of the deposited film.

[Example 1]
A microwave power source with a frequency of 2.45 GHz and a maximum output of 1.2 kW, a metal cylindrical plasma processing chamber with a diameter of 90 mm and a height of 500 mm, an oil rotary vacuum pump that evacuates the processing chamber, and a microwave from the oscillator to the plasma processing chamber The apparatus shown in FIG. 2 having a rectangular waveguide to be introduced into was used.
The gas supply pipe uses a sintered stainless steel gas supply pipe having a porous structure with an outer diameter of 15 mm and a length of 150 mm. The bottle holder is a cylindrical polyethylene having a diameter of 28 mm, a barrel diameter of 64 mm, a height of 206 mm, and an internal volume of 520 ml. After installing a terephthalate bottle (PET bottle), setting the vacuum outside the processing chamber to 7 kPa, the vacuum inside the bottle to 10 Pa, and introducing 3 sccm of hexamethyldisiloxane (hereinafter referred to as HMDSO) from the microwave oscillator A 500 W microwave was transmitted to generate plasma in the PET bottle and plasma treatment was performed to form a deposited film composed of an adhesive layer, a barrier layer, and an outer surface protective layer. The deposition time for each layer was 0.5 sec, 6 sec, and 0.5 sec, respectively.
When forming this deposited film, after forming an adhesive layer, oxygen is introduced at 30 sccm to form a barrier layer, and then the supply of oxygen is stopped to form an outer surface protective layer, which is then released to the atmosphere to produce a deposited film. The membrane was terminated.
The composition distribution in the depth direction of the silicon, oxygen, and carbon films by composition analysis in the film at this time is shown in FIG. 3, the sum of the concentrations of silicon and oxygen is Si + O, and FIG. Is shown in FIG.

[Example 2]
A vapor deposition film was formed in the same manner as in Example 1 except that the amount of oxygen supplied during the formation of the outer surface protective layer was 3 sccm.

[Example 3]
The microwave output was changed to 50 W when the adhesive layer was formed, 500 W when the barrier layer was formed, and 50 W when the outer surface protective layer was formed. The amount of oxygen supplied when forming the outer surface protective layer was 6 sccm. A deposited film was formed in the same manner as in Example 1 except that.

[Comparative Example 1]
A vapor deposition film was formed in the same manner as in Example 1 except that the amount of oxygen supplied during the formation of the outer surface protective layer was 9 sccm.
The composition distribution in the depth direction of the film of silicon, oxygen, and carbon was measured on the inner surface of the bottle body in the same manner as in Example 1 and shown in FIG. Further, the sum of the concentrations of silicon and oxygen is expressed as Si + O and shown in FIG.

[Comparative Example 2]
A vapor deposition film was formed in the same manner as in Example 1 except that the amount of oxygen supplied during the formation of the outer surface protective layer was 15 sccm.

[Comparative Example 3]
A vapor deposition film was formed in the same manner as in Example 1 except that the amount of oxygen supplied during the formation of the outer surface protective layer was 30 sccm.

  The evaluation results of the above-described examples and comparative examples are shown in Table 1. In each comparative example, a vapor deposition film having an outer surface protective layer having a carbon (C) concentration of 15 element% or more is not formed, and vapor deposition is performed. Only the carbon (C) concentration on the outer surface of the membrane is listed in Table 1. From the results in Table 1, it can be seen that the deposited film of the present invention is excellent in both oxygen barrier properties and moisture barrier properties.

The figure which shows the elemental composition in the thickness direction of the vapor deposition film of this invention. The figure which shows the structure of the plasma processing apparatus for forming the vapor deposition film of this invention. The element concentration figure in the thickness direction of the vapor deposition film of Example 1. FIG. The reference figure which showed the density | concentration of the silicon and oxygen in FIG. 3 as Si + O. The reference figure which showed the bond energy of the silicon in FIG. The element concentration figure in the thickness direction of the vapor deposition film of the comparative example 1. The reference figure which showed the density | concentration of the silicon and oxygen in FIG. 6 as Si + O.

Claims (3)

In the deposited film formed on the surface of the plastic bottle by the plasma CVD method using the organometallic compound and the oxidizing gas as the reaction gas,
The vapor-deposited film has an adhesive layer region located on the surface of the plastic bottle, a barrier layer region located on the adhesive layer region, and an outer surface protective layer region located on the surface of the barrier layer region. And
The adhesion layer region has a (M + O) concentration lower than the barrier layer region and (C) on the basis of the three elements based on the metal element (M), oxygen (O) and carbon (C) derived from the organometallic compound. The barrier layer region has a (M + O) concentration higher than that of the outer surface protective layer region, and the (M + O) concentration at the interface between the barrier layer region and the outer surface protective layer region. Is substantially continuously changed, and the outer surface protective layer region has a (C) concentration of 15 element% or more. The deposited film according to claim 1 , wherein the organometallic compound is an organosilicon compound, and the metal (M) is silicon (Si). Plastic bottles deposited film according to claim 1 or 2, characterized in that it is formed on the inner surface.

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