TWI576242B - Gas barrier plastic molded body and manufacturing method thereof - Google Patents

Description

Gas barrier plastic molded body and method of manufacturing same

The present invention relates to a gas barrier plastic molded body and a method of manufacturing the same.

In the prior art, there is a chemical vapor deposition (CVD) method (for example, see Patent Document 1) as a technique for forming a gas barrier film (hereinafter, a gas barrier film is also known). Patent Document 1 discloses a method of using a ruthenium compound as a raw material and a gas barrier film mainly composed of an inorganic oxide in an inner surface layer of a plastic container. However, in the method of forming a thin film by the plasma CVD method, the plasma may damage the surface of the film during film formation, and the density of the film is easily damaged, which may become an obstacle to improve gas barrier properties or ensure film adhesion. Further, the plasma CVD method uses a plasma to decompose a raw material gas to ionize it, and collides ions accelerated by an electric field on a surface of a plastic container to form a thin film. Therefore, a high-frequency power source and a high-frequency power matching device are required. The inevitable problem of expensive equipment.

In order to solve this problem, the present applicant has disclosed a technique of decomposing a raw material gas in contact with a heat generating body which generates heat, and depositing the generated chemical species directly or in the gas phase through a reaction process, and then depositing the film on the substrate as a film, that is, a CVD method called a heating element CVD method, a Cat-CVD method (Catalytic Chemical Vapor Deposition) or a hot wire CVD method (hereinafter, referred to as a heating element CVD method in the present specification), in plastics A gas barrier film is formed on the surface of the container (for example, refer to Patent Document 2 or 3). Patent Document 2 discloses a technique in which an AlO _x film or a SiO _x film is formed as an oxide film by using a mixed gas of a non-self-igniting raw material and ozone as a material gas. Patent Document 3 proposes to form, for example, a hydrogen-containing SiN _x film, a hydrogen-containing DLC (diamond-like carbon) film, a hydrogen-containing SiO _x film or a film by combining a plurality of gases as a material gas. A technique of a heating body CVD method for a hydrogen SiC _x N _y film.

As a method of forming a gas barrier film, there is disclosed a technique of forming a SiN (nitriding) by using a heating element CVD method on a surface of a substrate containing a thermoplastic resin, and using a nitrogen-containing gas and a decane-based gas as a material gas.矽) or a SiON (yttrium oxynitride) film (for example, refer to Patent Document 4). Further, although it is not a gas barrier film, as a method of forming a film by using a heating element CVD method, for example, a technique is disclosed in which a material gas is brought into contact with a heating element heated to 800 to 2000 ° C to generate a chemical species, and the chemical species is produced. A film is formed by a thermal CVD method on a substrate heated to 150 to 400 ° C (see, for example, Patent Document 5). Patent Document 5 discloses a method of depositing a film using a gas in which a plurality of gases are mixed. Further, a technique of improving the gas barrier properties of the SiCN film by using a raw material gas of a decazane system has been disclosed (for example, see Patent Document 7).

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-200043

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-127053

[Patent Document 3] WO 2006/126677

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2008-208404

[Patent Document 5] Japanese Patent Laid-Open Publication No. 63-40314

[Patent Document 6] Japanese Patent Laid-Open Publication No. 08-53116

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2010-235979

However, the conventional heating element CVD method is a method in which a mixed gas of two or more kinds of gases is used as a material gas in combination with a constituent element of a target film. In this method, the control of the supply amount of each gas is complicated, and it is difficult to stably obtain a film having a high gas barrier property. Further, there is a case where a chemical species different from the target chemical species is generated, and there is a limit to improvement in gas barrier properties. Further, according to the study by the inventors of the present invention, the film does not necessarily exhibit the same gas barrier properties even if it contains the same constituent elements, and the gas barrier property of the film is affected by the bonding state between the elements in the deposited film or the voids in the film. The impact of the state. Heretofore, a technique of forming a film having a high gas barrier property using a single material gas has not been disclosed. Further, in order to further improve the gas barrier properties, research on the type of the heat generating body capable of selectively depositing the film having the target bonding state has hardly been carried out. For example, the inventors of the present invention have intensively tested and found that in the technique described in Patent Document 7, it is necessary to raise the temperature of the substrate in order to improve the gas barrier property, and the PET (Polyethylene Terephthalate) substrate is used. Since the heat resistance is insufficient, the gas barrier properties of the PET substrate cannot be improved.

Accordingly, it is an object of the present invention to provide a gas barrier plastic molded article having a high gas barrier property. Further, a second object of the present invention is to provide a method for producing a plastic molded body having a gas barrier film which can be carried out using a single raw material gas having high safety and which can be produced without requiring an expensive machine.

The gas barrier plastic molding system of the present invention comprises a plastic molded body and a gas barrier film disposed on the surface of the plastic molded body; wherein the gas barrier film comprises bismuth (Si), carbon (C), and oxygen (O) And hydrogen (H) as a constituent element, and includes the Si-containing layer having a Si content of 40.1% or more as indicated by (number 1).

(Number 1) Si content rate [%] = {(Si content [Atomic%]) / (Total content of Si, O and C [Atomic%])} × 100 in the number 1, content of Si, O or C It is the content of the three elements of Si, O and C.

In the gas barrier plastic molded article of the present invention, the C content of the Si-containing layer (number 2) is preferably from 22.8 to 45.5%.

(Number 2) C content rate [%] = {(C content [atomic %]) / (total content of Si, O and C [atomic %])} × 100 in the number 2, content of Si, O or C It is the content of the three elements of Si, O and C.

In the gas barrier plastic molded article of the present invention, the O content shown by the number (3) of the Si-containing layer is preferably 2.0 to 35.8%.

(Number 3) O content rate [%] = {(O content [atomic %]) / (total content of Si, O and C [atomic %])} × 100 in the number 3, content of Si, O or C It is the content of the three elements of Si, O and C.

In the gas barrier plastic molded article of the present invention, the Si-containing layer preferably has a hydrogen content of 21 to 46% by atom.

In the gas barrier plastic molded article of the present invention, the density of the gas barrier film is preferably from 1.30 to 1.47 g/cm ³ .

In the gas barrier plastic molded article of the present invention, it is preferable to include a region in which the X-ray electron spectroscopic analysis (hereinafter, referred to as XPS analysis) is performed on the Si-containing layer under the condition (1). The main peak is observed at the position where the peak of the bond energy of Si is present.

Condition (1) sets the measurement range to 95 to 105 eV.

It can be made into a gas barrier film with better gas barrier properties.

In the gas barrier plastic molded article of the present invention, it is preferred that the X-ray photoelectron spectroscopy of the Si-containing layer is carried out under the condition (2), and the peak position of the bonding energy of Si and Si is not observed. crest.

Condition (2) sets the measurement range to 120 to 150 eV.

It was confirmed that a Si-H bond was present in the Si-containing layer.

In the gas barrier plastic molded article of the present invention, the gas barrier film is preferably formed by a heating element CVD method.

In the gas barrier plastic molded article of the present invention, the film thickness of the gas barrier film is preferably 5 nm or more. It can be made into a gas barrier film with better gas barrier properties.

In the gas barrier plastic molded article of the present invention, the plastic molded body is in the form of a container, a film or a sheet.

The method for producing a gas barrier plastic molded article of the present invention comprises the following steps of forming a film: contacting a material gas with a heat generating body that generates heat, decomposing the material gas to form a chemical species, and causing the chemical species to reach the surface of the plastic molded body Thereby, a gas barrier film is formed; characterized in that an organic decane compound represented by the formula (Chemical Formula 1) is used as the above-mentioned source gas, and a component selected from the group consisting of Mo, W, Zr, Ta, V, Nb, Hf is used. a material of one or more of the metal elements in the group as the heat generating body, and the heat of the heat generating body The temperature is set to 1550~2400 °C.

(Chemical Formula 1) H ₃ Si-C _n -X In Chemical 1, 1 is 2 or 3, and X is SiH ₃ , H or NH ₂ .

In the method for producing a gas barrier plastic molded article of the present invention, the organodecane compound represented by the above formula (Chemical Formula 1) is preferably a vinyl decane, a dioxane or a dialkyl acetylene or a 2-amino group. Ethyl decane. A film having more excellent gas barrier properties can be effectively formed.

In the method for producing a gas barrier plastic molded article of the present invention, as the heat generating body, metal ruthenium, ruthenium-based alloy or tantalum carbide is preferably used, metal tungsten, tungsten-based alloy or tungsten carbide is used, and metal molybdenum and molybdenum are used. Base alloy or molybdenum carbide, or use of metal ruthenium, ruthenium based alloy or tantalum carbide. Since the catalytic activity of the materials is high, the raw material gases can be more efficiently decomposed. Further, chemical species can be efficiently produced to form a film having a high gas barrier property.

The present invention provides a gas barrier plastic molded body having a high gas barrier property. Further, a second object of the present invention is to provide a method for producing a plastic molded body having a gas barrier film which can be carried out using a single raw material gas having high safety and which can be produced without requiring an expensive machine.

Hereinafter, the exemplary embodiments of the present invention will be described in detail, but the present invention is not limited to the descriptions. The embodiment can be variously modified as long as the effects of the present invention are achieved.

Fig. 1 is a cross-sectional view showing a basic configuration of a gas barrier plastic molded article of the present embodiment. The gas barrier plastic molded body 90 of the present embodiment includes plastic The molded body 91 and the gas barrier film 92 provided on the surface of the plastic molded body 91, and the gas barrier film 92 contains bismuth (Si), carbon (C), oxygen (O), and hydrogen (H) as constituent elements, and includes The Si-containing layer having a Si content of 40.1% or more is shown by the number (1).

(Number 1) Si content rate [%] = {(Si content [Atomic%]) / (Total content of Si, O and C [Atomic%])} × 100 in the number 1, content of Si, O or C It is the content of the three elements of Si, O and C.

The resin constituting the plastic molded body 91 is, for example, polyethylene terephthalate (PET), polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene resin, poly Acrylic resin (PP, Polypropylene), cycloolefin copolymer resin (COC, Cycloolefin Copolymer, cyclic olefin copolymerization), ionic polymer resin, poly-4-methylpentene-1 resin, polymethyl methacrylate resin , polystyrene resin, ethylene-vinyl alcohol copolymer resin, acrylonitrile resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyamide resin, polyamidamine resin, polyacetal resin, polycarbonate Ester resin, polyfluorene resin, or tetrafluoroethylene resin, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene resin. One type of these may be used as a single layer or a laminate, but it is preferably a single layer in terms of productivity. Further, the type of the resin is more preferably PET.

In the gas barrier plastic molded body 90 of the present embodiment, the plastic molded body 91 is in the form of a container, a film or a sheet. The shape can be appropriately set depending on the purpose and use, and is not particularly limited. The container includes a lid, a bolt or a seal The container used, or the container used in the open state without using the container. The size of the opening can be appropriately set depending on the content. The plastic container includes a plastic container having a moderate rigidity and a specific wall thickness, and a plastic container formed of a sheet material having no rigidity. The invention is not limited by the method of manufacture of the container. The contents are, for example, beverages such as water, tea drinks, refreshing drinks, carbonated drinks or fruit drinks, liquids, slims, powders or solid foods. Also, the container can be any of a recyclable container or a disposable container. The film or sheet comprises long strips and cut pieces. The film or sheet may be either extended or unstretched. The present invention is not limited by the method of manufacturing the plastic formed body 91.

The thickness of the plastic molded body 91 can be appropriately set depending on the purpose and use, and is not particularly limited. For example, when the plastic molded body 91 is a container such as a bottle for a drink, the wall thickness of the bottle is preferably 50 to 500 μm, more preferably 100 to 350 μm. Further, in the case of forming a film of a packaging bag, the thickness of the film is preferably from 3 to 300 μm, more preferably from 10 to 100 μm. In the case of a substrate of a flat panel display such as an electronic paper or an organic EL (Organic Electro-Luminescence), the thickness of the film is preferably 25 to 200 μm, more preferably 50 to 100 μm. In the case of a sheet for forming a container, the thickness of the sheet is preferably from 50 to 500 μm, more preferably from 100 to 350 μm. Further, when the plastic molded body 91 is a container, the gas barrier film 92 is provided on either or both of the inner wall surface and the outer wall surface. Further, when the plastic molded body 91 is a film, the gas barrier film 92 is provided on one side or both sides.

The gas barrier film 92 contains cerium (Si), carbon (C), oxygen (O), and hydrogen (H) as constituent elements, and includes Si containing a Si content of 40.1% or more as indicated by (number 1). Floor. The Si content of the Si-containing layer is more preferably 40.7% or more. The upper limit of the Si content of the Si-containing layer is preferably set to 57.7%. More preferably 55.7%. If the Si content of the Si-containing layer is less than 40.1%, the gas barrier property may be insufficient. When the gas barrier film 92 includes a Si-containing layer having a Si content of 40.1% or more, another layer such as a low Si-containing layer may be provided in the upper layer or the lower layer or the upper and lower layers of the Si-containing layer. Further, the gas barrier film 92 as a whole may be the Si-containing layer.

In the gas barrier plastic molded article of the present embodiment, the C content of the Si-containing layer (number 2) is preferably from 22.8 to 45.5%. More preferably 24.8~45.4%.

(Number 2) C content rate [%] = {(C content [atomic %]) / (total content of Si, O and C [atomic %])} × 100 in the number 2, content of Si, O or C It is the content of the three elements of Si, O and C.

In the gas barrier plastic molded article of the present embodiment, the O content shown by the number (3) of the Si-containing layer is preferably 2.0 to 35.8%. More preferably 6.0 to 33.8%.

(Number 3) O content rate [%] = {(O content [atomic %]) / (total content of Si, O and C [atomic %])} × 100 in the number 3, content of Si, O or C It is the content of the three elements of Si, O and C.

The Si content, the C content, or the O content can be measured, for example, by performing XPS (X-ray Photoelectron Spectroscopy) analysis on the gas barrier film 92.

In the gas barrier plastic molded article of the present embodiment, the hydrogen content of the Si-containing layer is preferably from 21 to 46 atom% (at.%). More preferably 25~42 at.%. The hydrogen content can be measured by a Laceford inverse scattering spectrum method (hereinafter referred to as RBS analysis). By relatively increasing the hydrogen content, it is easy to match the deformation of the plastic substrate. On the other hand, if the amount of hydrogen contained is suppressed to a small extent, the film quality is hardened, so that cracks are remarkably generated when the plastic substrate is deformed. Further, the ruthenium content of the gas barrier film obtained by RBS analysis is preferably from 20 to 38 at.%. More preferably 22~36 at.%. The carbon content of the gas barrier film obtained by RBS analysis is preferably 15 to 25 at.%. More preferably 18~22 at.%. The oxygen content of the gas barrier film obtained by RBS analysis is preferably from 12 to 26 at.%. More preferably 15~21 at.%. Further, the gas barrier film 92 may contain other elements in addition to Si, C, O, and H. Other elements are a metal element derived from a heating element such as Mo (molybdenum), and N (nitrogen).

In the gas barrier plastic molded article of the present embodiment, the density of the gas barrier film is preferably from 1.30 to 1.47 g/cm ³ , more preferably from 1.33 to 1.46 g/cm ³ , and particularly preferably from 1.35 to 1.40 g/m. ³ .

In the gas barrier plastic molded article of the present embodiment, it is preferable to include a region in which the main peak is observed at the peak position of the bonding energy of Si and Si when the Si-containing layer is subjected to XPS analysis under the condition (1). (Herein, there is also a case where a peak observed at a peak where the bonding energy of Si and Si is observed is called an Si peak).

Condition (1) sets the measurement range to 95 to 105 eV.

When the XPS analysis is carried out under the condition (1), the main peak is observed at the position where the peak of the bonding energy of Si and Si appears. Here, in the present specification, the main peak refers to the peak having the highest intensity among the peaks observed in the peak separation in the condition (1). The bonding state assumed based on the peak appearing at the peak of the bonding energy of Si and Si is a Si-Si bond or a Si-H bond. In the present embodiment, it is preferred that the main bond of the Si peak is a Si-H bond. The combination of the gas barrier film 92 In addition to the Si-Si bond or the Si-H bond, the bond state of the object is, for example, a Si-C bond, a Si-O bond, a C-H bond, a C-C bond, a C-O bond, a Si-O-C bond, a C-O-C bond, or an O-C-O bond.

In the gas barrier plastic molded article of the present embodiment, when the Si-containing layer is subjected to XPS analysis under the condition (2), no peak is observed at the peak of the bonding energy of Si and Si.

Condition (2) sets the measurement range to 120 to 150 eV.

It can be confirmed by XPS analysis under the conditions (1) and (2) that the Si peak is mainly a Si-Si bond or a Si-H bond. That is, under the condition (1), there is a peak at the peak of the bonding energy of Si and Si, and under the condition (2), there is no peak at the peak of the bonding energy of Si and Si, thereby confirming that the Si peak shows Si. -H key. Thereby, the Barrier Improvement Factor (hereinafter referred to as BIF) obtained by (number 4) can be set to 6 or more.

(Number 4) BIF = [oxygen permeability of a plastic formed body without a film] / [oxygen permeability of a gas barrier plastic molded body]

According to the study by the inventors of the present invention, in order to exhibit higher gas barrier properties, it is preferred that the gas barrier film 92 has a tilting composition in which the bond of Si and H (Si-H bond) is biased against the surface of the film. Argon ion etching can be performed in the XPS analysis under the condition (1) to confirm that the gas barrier film 92 has an inclined composition. According to the analysis result, the surface Si peak of the gas barrier film 92 is the main peak, and the main peak is shifted toward the high bonding energy side as it goes toward the plastic formed body. Therefore, it is estimated that there are many Si-H bonds on the surface, but the composition gradually changes to SiC as it goes toward the direction of the plastic molded body, and then the SiOC from carbon to oxygen is changed to the SiOC with more oxygen than carbon. The interface of the body becomes SiO _x . The reason for having such a tilt composition is not clear. However, it is presumed that the interface of the plastic formed body is deposited with an SiO-based compound such as SiO ₂ or SiO _x due to the influence of oxygen from the plastic formed body during the film formation process, but the self-forming plastic is formed. From the vicinity of the interface of 5 nm, the influence of the plastic formed body is reduced, the content of O is reduced, and the compound deposited becomes a compound of SiC system from SiOC to SiC, and the surface of the film contains Si-H more. key.

In the gas barrier plastic molded body 90 of the present embodiment, the film thickness of the gas barrier film 92 is preferably 5 nm or more. More preferably 10 nm or more. If it is less than 5 nm, there is a case where the gas barrier property is insufficient. Further, the upper limit of the film thickness of the gas barrier film 92 is preferably set to 200 nm. More preferably 100 nm. If the film thickness of the gas barrier film 92 exceeds 200 nm, cracks are likely to occur due to internal stress.

In the gas barrier plastic molded body 90 of the present embodiment, it is preferable that the gas barrier film 92 is formed by a heating element CVD method. The heating element CVD method is a method in which a raw material gas is brought into contact with a heating element that generates heat by electric heating in a vacuum chamber, and the generated chemical species is deposited on the substrate directly or in the gas phase after passing through the reaction process. It is a film. The heating element differs depending on its softening temperature, and usually causes it to heat up to 200 to 2200 ° C. However, by vacating the space between the substrate and the heating element, the temperature of the substrate can be kept at a low temperature of about 200 ° C above normal temperature. It can form a film without causing damage to a substrate that is not heat-resistant like plastic. Further, compared with other physical vapor deposition methods such as plasma CVD, vacuum vapor deposition, sputtering, and ion plating, the device is simple and can suppress the cost of the device itself. In the heating element CVD method, since a gas barrier film is formed by chemical species deposition, a dense film having a high bulk density is obtained as compared with the wet method.

Next, a film forming apparatus which can form a gas barrier film on the surface of a plastic molded body will be described. Fig. 2 is a schematic view showing one form of a film forming apparatus. 2 shows a device in which a plastic container 11 is used as the plastic molded body 91 and a gas barrier film 92 is formed on the inner surface of the plastic container 11.

The gas barrier plastic container manufacturing apparatus 100 shown in Fig. 2 includes a vacuum chamber 6 that houses a plastic container 11 as a plastic molded body 91, and an exhaust pump (not shown) that draws the vacuum chamber 6 into a vacuum; a raw material gas supply pipe 23 which is detachably disposed inside the plastic container 11 and supplies a material gas to the inside of the plastic container 11, and which is formed of an insulating and heat-resistant material; and a heat generating body 18 which is supplied by the raw material gas The tube 23 is supported; and a heating power source 20 that energizes the heating element 18 to generate heat.

The vacuum chamber 6 is formed therein with a space for accommodating the plastic container 11, which becomes the reaction chamber 12 for forming a film. The vacuum chamber 6 includes a lower chamber 13 and an upper chamber 15, which is detachably mounted to the upper portion of the lower chamber 13 and seals the inside of the lower chamber 13 with an O-ring 14. The upper chamber 15 has a drive mechanism (not shown), and moves up and down as the plastic container 11 is moved in and out. The internal space of the lower chamber 13 is formed in a manner slightly larger than the outer shape of the plastic container 11 accommodated therein.

The inner side of the vacuum chamber 6, especially the inner side of the lower chamber 13, is for preventing the reflection of light emitted by the heating of the heating element 18, preferably the inner surface 28 is a black inner wall, or the inner surface has a surface roughness. (Rmax) Concavities and convexities of 0.5 μm or more. The surface roughness (Rmax) is measured using, for example, a surface roughness measuring instrument (manufactured by Ulvac Techno, DEKTAX3). In order to make the inner surface 28 a black inner wall, there is a plating treatment such as black nickel plating or black chrome plating. RAYDENT (cold plating), blackening, etc., into a film treatment, or a method of applying a black paint to color. Further, it is preferable to provide a cooling device 29 such as a cooling pipe for flowing cooling water inside or outside the vacuum chamber 6, thereby preventing the temperature of the lower chamber 13 from rising. Among the vacuum chambers 6, particularly the following chambers 13, is intended to be in a state in which the heat generating body 18 is inserted into the plastic container 11 just in the state of being accommodated in the internal space of the lower chamber 13. By preventing the reflection of light and the cooling of the vacuum chamber 6, the temperature rise of the plastic container 11 and the thermal deformation accompanying this can be suppressed. Further, when the chamber 30 including the transparent body through which the emitted light generated by the self-heating heating element 18 passes, for example, the glass chamber is disposed inside the lower chamber 13, the glass chamber of the plastic container 11 is contacted. The temperature is hard to rise, so that the thermal influence on the plastic container 11 can be further alleviated.

The material gas supply pipe 23 is supported so as to be suspended in the center of the inner top surface of the upper chamber 15 so as to hang downward. The material gas 33 flows into the material gas supply pipe 23 via the flow rate adjusters 24a and 24b and the valves 25a to 25c. When the raw material gas 33 is supplied to the starting material as a liquid, it can be supplied by a foaming method. In other words, the flow rate is controlled by the flow rate adjuster 24a, and the foaming gas is supplied to the starting material 41a accommodated in the raw material tank 40a, and the starting material 41a is vaporized and supplied as the material gas 33.

The material gas supply pipe 23 preferably includes a cooling pipe and is integrally formed. The structure of the material gas supply pipe 23 is, for example, a double pipe structure. In the material gas supply pipe 23, the inner pipe of the double pipe serves as the material gas flow path 17, and one end thereof is connected to the gas supply port 16 provided in the upper chamber 15, and the other end serves as the gas discharge hole 17x. Thereby, the material gas is self-connected to the gas supply port The gas ejection hole 17x at the front end of the raw material gas flow path 17 of 16 is ejected. On the other hand, the pipe outside the double pipe is used to cool the cooling water flow path 27 of the material gas supply pipe 23, and functions as a cooling pipe. When the heating element 18 is energized and generates heat, the temperature of the material gas flow path 17 rises. In order to prevent the temperature from rising, cooling water is circulated in the cooling water flow path 27. In other words, at one end of the cooling water flow path 27, cooling water is supplied from a cooling water supply device (not shown) connected to the upper chamber 15, and the cooling water that has been cooled is returned to the cooling water supply device. On the other hand, the other end of the cooling water flow path 27 is sealed near the gas discharge hole 17x, and the cooling water is turned back and returned. The raw material gas supply pipe 23 is entirely cooled by the cooling water flow path 27. The thermal influence on the plastic container 11 can be reduced by performing cooling. Therefore, the material of the material gas supply pipe 23 is preferably an insulator and has a large thermal conductivity. For example, it is preferably a ceramic tube formed of a material mainly composed of aluminum nitride, tantalum carbide, tantalum nitride or aluminum oxide, or mainly composed of aluminum nitride, tantalum carbide, tantalum nitride or aluminum oxide. The material is coated with a metal tube on the surface. The heating element can be stably energized, has durability, and can efficiently discharge heat generated by the heating element by heat conduction.

The material gas supply pipe 23 may be provided as follows, as another form not shown. That is, the raw material gas supply pipe is provided as a double pipe, and the outer pipe is used as a material gas flow path to open a hole in the side wall of the outer pipe, and preferably a plurality of holes are opened. On the other hand, the inner tube of the double pipe of the material gas supply pipe is formed of a dense pipe, and the cooling water flows as a cooling water flow path. The heat generating system is routed along the side wall of the raw material gas supply pipe, and the raw material gas provided in the hole on the side wall of the outer pipe contacts the heat generating body along the side wall, which is effective The rate is preferably a chemical species.

When the gas ejection hole 17x is excessively separated from the bottom of the plastic container 11, it is difficult to form a film inside the plastic container 11. In the present embodiment, the length of the material gas supply pipe 23 is preferably such that the distance L1 from the gas discharge hole 17x to the bottom of the plastic container 11 is 5 to 50 mm. The uniformity of the film thickness is improved. A uniform film can be formed on the inner surface of the plastic container 11 at a distance of 5 to 50 mm. If the distance is larger than 50 mm, there is a case where it is difficult to form a film on the bottom of the plastic container 11. Further, when the distance is less than 5 mm, there is a case where it is difficult to discharge the material gas, or the film thickness distribution is not uniform. This fact can also be grasped theoretically. In the case of a 500 ml container, since the main body diameter of the container is 6.4 cm, the average free path of air at normal temperature is λ = 0.68/Pa [cm], so the molecular flow is pressure <0.106 Pa, and the viscous flow is pressure > 10.6. Pa, the intermediate flow is 0.106 Pa <pressure < 10.6 Pa. When the gas pressure at the time of film formation is 5 to 100 Pa, the gas flow changes from the intermediate flow to the viscous flow, and the distance between the gas ejection hole 17x and the bottom of the plastic container 11 is optimal.

The heating element 18 promotes decomposition of the material gas. The heating element 18 is formed in a wiring shape, and one end of the heating element 18 is connected to the connecting portion 26a, and the connecting portion 26a is provided below the fixed position of the upper chamber 15 of the material gas supply pipe 23 to connect the wiring 19 to the heating element 18. position. Further, the front end portion is supported by the insulating ceramic member 35 provided on the gas ejection hole 17x. Further, returning, the other end of the heating element 18 is connected to the connecting portion 26b. In this manner, since the heating element 18 is supported along the side surface of the material gas supply pipe 23, it is disposed so as to be positioned on the substantially main axis of the internal space of the lower chamber 13. Figure In the case where the heating element 18 is disposed along the periphery of the material gas supply pipe 23 so as to be parallel to the axis of the material gas supply pipe 23, the connection portion 26a may be used as a starting point and spirally wound around the material gas supply. The side surface of the tube 23 is supported by the insulating ceramic 35 fixed in the vicinity of the gas ejection hole 17x, and then folded back to the connecting portion 26b. Here, the heating element 18 is fixed to the material gas supply pipe 23 by being hung on the insulating ceramic 35. In the case where the heat generating body 18 is disposed in the vicinity of the gas discharge hole 17x of the material gas supply pipe 23, the heat generating body 18 is disposed on the outlet side of the gas discharge hole 17x. Thereby, since the material gas discharged from the gas ejection hole 17x is easily brought into contact with the heat generating body 18, the material gas can be efficiently activated. Here, it is preferable that the heating element 18 is disposed slightly away from the side surface of the material gas supply pipe 23. The purpose is to prevent an abrupt temperature rise of the material gas supply pipe 23. Further, the chance of contact with the material gas ejected from the gas ejection hole 17x and the material gas of the reaction chamber 12 can be increased. The outer diameter of the material gas supply pipe 23 including the heat generating body 18 must be smaller than the inner diameter of the mouth portion 21 of the plastic container. The purpose is to insert the material gas supply pipe 23 including the heating element 18 from the mouth portion 21 of the plastic container. Therefore, when the heating element 18 is separated from the surface of the material gas supply pipe 23 to the extent necessary, the material gas supply pipe 23 is easily contacted when being inserted from the mouth portion 21 of the plastic container. The width of the heating element 18 is preferably 10 mm or more and (the inner diameter of the mouth portion -6) mm or less in consideration of the positional deviation when the mouth portion 21 of the plastic container is inserted. For example, the inner diameter of the mouth portion 21 is about 21.7 to 39.8 mm.

Since the heating element 18 has electrical conductivity, it can be heated by, for example, energization. In the apparatus shown in FIG. 2, the heating source 18 is connected to the heating element 18 via the connecting portions 26a and 26b and the wiring 19. By using a heating power source 20 The heating element 18 is supplied with power and the heating element 18 generates heat. Furthermore, the present invention is not limited to the heat generating method of the heat generating body 18.

Further, since the stretching ratio of the plastic container 11 at the time of molding from the mouth portion 21 of the plastic container to the shoulder portion of the container is small, if the heat generating body 18 which generates heat at a high temperature is disposed in the vicinity, deformation due to heat is likely to occur. According to the experiment, if the position where the connection portion 26a, 26b, that is, the connection position of the wiring 19 and the heating element 18, is not separated from the lower end of the mouth portion 21 of the plastic container by 10 mm or more, the shoulder portion of the plastic container 11 is thermally deformed. When it exceeds 50 mm, it is difficult to form a film on the shoulder portion of the plastic container 11. Therefore, the heating element 18 is preferably disposed such that its upper end is located 10 to 50 mm below the lower end of the mouth portion 21 of the plastic container. That is, it is preferable to provide such that the distance L2 between the connecting portions 26a and 26b and the lower end of the mouth portion 21 is 10 to 50 mm. It can suppress the thermal deformation of the shoulder of the container.

Further, the exhaust pipe 22 communicates with the internal space of the upper chamber 15 via the vacuum valve 8, and the air in the reaction chamber 12 inside the vacuum chamber 6 is discharged by an exhaust pump (not shown).

Then, a method of manufacturing a gas barrier plastic molded article of the present embodiment will be described by taking a case where a gas barrier film is formed on the inner surface of the gas barrier plastic container 11 as an example. The method for producing a gas barrier plastic molded article according to the present embodiment includes a film forming step of bringing the material gas 33 into contact with the heat generating body 18 that generates heat, and decomposing the material gas 33 to form a chemical species 34, so that the chemical species 34 reaches the plastic. The surface of the molded body (the inner surface of the plastic container 11 in Fig. 2), thereby forming a gas barrier film; using the organic decane compound represented by the formula (Chemical Formula 1) as the raw material gas 33, and using the inclusion of the selected material A material of one or two or more metal elements of Mo, W, Zr, Ta, V, Nb, and Hf is used as the heating element 18, and the heating temperature of the heating element 18 is set to 1550 to 2400 °C.

(Chemical Formula 1) H ₃ Si-C _n -X In Chemical 1, 1 is 2 or 3, and X is SiH ₃ , H or NH ₂ .

When a film is formed using the organodecane compound represented by the above formula (Chemical Formula 1) as a material gas, if the plasma CVD method is used, the oxygen permeability of a 500 ml PET bottle can only be suppressed to 2 About 1 point, the practical performance is not sufficient. It is known that if a film containing DLC or SiO _{x is} formed by a plasma CVD method, the oxygen permeability of a 500 ml PET bottle can be suppressed to less than 1/10, but when filled with a carbonated beverage, the bottle is accompanied. The expansion expands and the gas barrier properties decrease. Specifically, if a 500 ml PET bottle (resin amount 23 g) which forms a DLC film or a SiO _x film by a plasma CVD method is filled with 4 GV (gas volume) of carbonated water and maintained at 38 ° C, 5 In the day, the capacity of the PET bottle is usually expanded by 18 to 21 cm ³ (22 to 26 cm ^{3 in} the case of a PET bottle without film formation), and the oxygen permeability after expansion is increased to 1.5 to 2.9 times. This is a result of a comprehensive manifestation of the damage of the film caused by the expansion and expansion of the PET bottle. On the other hand, when a film is formed using the organic decane compound represented by the above formula (Chemical Formula 1) as a material gas, the oxygen permeability of a 500 ml PET bottle can be obtained by using a heating element CVD method. When it is reduced to, for example, 1/10 or less, sufficient practical performance can be obtained. Further, when the carbonated beverage is filled, the expansion of the bottle can be effectively suppressed, and the gas barrier properties are not substantially lowered. Specifically, when a 500 ml PET bottle (resin amount 23 g) formed by using a heating element CVD method is filled with 4 GV (gas volume) of carbonated water and kept at 38 ° C for 5 days, usually The bottle capacity is only expanded by 13~17 cm ³ (22~26 cm ³ without the film forming bottle), and the oxygen permeability after expansion stops at 1.2~1.3 times.

(Installation of plastic molded body to film forming apparatus)

First, a vent (not shown) is opened to open the inside of the vacuum chamber 6 to the atmosphere. In the state where the upper chamber 15 is removed, the plastic container 11 as the plastic molded body 91 is inserted into the reaction chamber 12 from the upper opening portion of the lower chamber 13 and housed therein. Thereafter, the upper chamber 15 is lowered, and the material gas supply pipe 23 attached to the upper chamber 15 and the heat generating body 18 fixed thereto are inserted into the plastic container 11 from the mouth portion 21 of the plastic container. Then, the upper chamber 15 abuts against the lower chamber 13 via the O-ring 14, whereby the reaction chamber 12 becomes a sealed space. At this time, the interval between the inner wall surface of the lower chamber 13 and the outer wall surface of the plastic container 11 is kept substantially uniform, and the interval between the inner wall surface of the plastic container 11 and the heat generating body 18 is also kept substantially uniform.

(pressure adjustment step)

Then, after the vent (not shown) is closed, an exhaust pump (not shown) is operated, and the vacuum valve 8 is opened to discharge the air in the reaction chamber 12. At this time, not only the internal space of the plastic container 11, but also the space between the outer wall surface of the plastic container 11 and the inner wall surface of the lower chamber 13 is exhausted to become a vacuum. That is, the entire reaction chamber 12 is exhausted. Further, it is preferred to reduce the pressure necessary in the reaction chamber 12 to, for example, 1.0 to 100 Pa, more preferably 1.4 to 50 Pa. If it is less than 1.0 Pa, there is a case where exhaust time is consumed. In addition, when it exceeds 100 Pa, the amount of impurities in the plastic container 11 increases, and a container having a high barrier property cannot be obtained. If the pressure is reduced from atmospheric pressure to 1.4~50 Pa, a moderate vacuum pressure and a moderate residual vapor pressure from the atmosphere, equipment and containers can be obtained, and a barrier film can be easily formed.

(film formation step - energization of the heating element)

Then, the heating element 18 generates heat, for example, by energization. The material of the heating element 18 includes one or two selected from the group consisting of Mo (molybdenum), W (tungsten), Zr (zirconium), Ta (钽), V (vanadium), Nb (铌), and Hf (铪). Those who have above the metal elements. More preferably, it is one or more metal elements selected from the group consisting of Mo, W, Zr, and Ta. The heating temperature of the heating element 18 is set to 1550 to 2400 °C. More preferably, it is 1700~2100 °C. If it is less than 1550 ° C, the raw material gas cannot be efficiently decomposed, and it takes time and effort to form a film. If it exceeds 2400 ° C, the heat generation temperature is excessive and it is uneconomical. Further, there is a case where the material of the heating element 18 is deformed due to the material. There is a concern about thermal damage to the plastic formed body.

The material containing the metal element for the heating element 18 is preferably a pure metal, an alloy or a carbide of a metal. When an alloy containing Mo, W, Zr, Ta, V, Nb or Hf as a main component is used as the heating element 18, it is preferable that the content of the component other than the metal as the main component is 25 mass. %the following. More preferably, it is 10 mass% or less, More preferably, it is 1 mass% or less. In the case where tantalum carbide (TaC _x ) is used as the heat generating body 18, the ratio of carbon atoms in tantalum carbide (TaC _x ) is preferably more than 0% by mass and not more than 6.2% by mass. More preferably, it is 3.2 mass% or more and 6.2 mass% or less. In the case where tantalum carbide (HfC _x ) is used as the heating element 18, the ratio of carbon atoms in the niobium carbide (HfC _x ) is preferably more than 0% by mass and not more than 6.3% by mass. More preferably, it is 3.2 mass % or more and 6. mass % or less. In the case where tungsten carbide (WC _x ) is used as the heating element 18, the ratio of carbon atoms in the tungsten carbide (WC _x ) is preferably more than 0% by mass and not more than 6.1% by mass in terms of a mass ratio. More preferably, it is 3.0 mass% or more and 6.1 mass% or less. Ratio of carbon atoms to the use of molybdenum carbide (MoC _x) as the case where the heat generating element 18, preferably molybdenum carbide (MoC _x) in a mass ratio of more than 0 mass% and 5.9 mass% or less. More preferably, it is 2.9 mass% or more and 5.9 mass% or less.

(film formation step - introduction of raw material gas)

Thereafter, an organic decane compound represented by the formula (Chemical Formula 1) is supplied as the material gas 33. In the first embodiment, the bond between the carbons in the hydrogen carbide structure corresponding to C _n may be either a single bond, a double bond or a triple bond. More preferably, it is a linear structure. Further, it is preferred to include a double bond or a triple bond having a small amount of hydrogen. For example, when n=2, the example of the state of C _n is a single bond (CC ₂ H ₄ ) between CCs, a double bond between CCs (C ₂ H ₂ ), and a triple bond between CCs. The aspect (C ₂ ). When n=3, the sample of C _n is a single bond (CC ₃ H ₆ ) between CC, a single bond and a double bond between CC (C ₃ H ₄ ), and a single CC The key and the three-button aspect (C ₃ H ₂ ). Specifically, the organodecane compound represented by the formula (Chemical Formula 1) is, for example, vinyl decane (H ₃ SiC ₂ H ₃ ), dioxane (H ₃ SiC ₂ H ₄ SiH ₃ ), dialkyl acetylene. (H ₃ SiC ₂ SiH ₃ ), 2-aminoethyl decane (H ₃ SiC ₂ H ₄ NH ₂ ). Among them, vinyl decane, dioxane or dialkyl acetylene is preferred.

The material gas 33 is supplied by the flow rate control by the gas flow rate adjuster 24a. Further, the carrier gas is flow-controlled by the gas flow rate adjuster 24b as needed, and is mixed in the source gas 33 near the valve 25c. The carrier gas is an inert gas such as argon gas, helium gas or nitrogen gas. Thus, the material gas 33 is controlled by the gas flow rate adjuster 24a. In the state where the flow rate is controlled by the carrier gas, the gas discharge hole 17x of the material gas supply pipe 23 is ejected from the gas generating hole 17 of the raw material gas supply pipe 23 in the plastic container 11 which is depressurized to a specific pressure. Preferably, after the heating element 18 is heated up in this manner, the raw material gas 33 is discharged. At the initial stage of film formation, the chemical element 34 which is sufficiently activated can be generated by the heating element 18, and a film having a high gas barrier property can be obtained.

When the material gas 33 is a liquid, it can be supplied by a foaming method. The foaming gas system used in the foaming method is an inert gas such as nitrogen, argon or helium, and more preferably nitrogen. In other words, when the flow rate is controlled by the gas flow rate adjuster 24a while the flow rate is controlled by the gas flow rate adjuster 24a, the starting material 41a in the raw material tank 40a is foamed, and the starting material 41a is vaporized and mixed into the bubbles. In this manner, the material gas 33 is supplied in a state of being mixed with the foaming gas. Further, while the carrier gas is controlled to flow rate by the gas flow rate adjuster 24b, it is mixed into the source gas 33 near the valve 25c. In this manner, the material gas 33 is discharged from the gas ejection hole 17x of the material gas supply pipe 23 to the heat generating body 18 that generates heat in the plastic container 11 which is depressurized to a specific pressure in a state where the flow rate is controlled by the carrier gas. Here, the flow rate of the bubbling gas is preferably from 3 to 50 sccm, more preferably from 5 to 15 sccm. The flow rate of the carrier gas is not particularly limited, and is preferably 0 to 80 sccm. More preferably 5~50 sccm. The pressure in the plastic container 11 can be adjusted to 20 to 80 Pa by the flow rate of the carrier gas.

(film formation step - film formation)

Once the material gas 33 comes into contact with the heating element 18, the chemical species 34 is generated. The gas barrier film is deposited by causing the chemical species 34 to reach the inner wall of the plastic container 11. In the film forming step, the heating element 18 is heated and the material gas is sprayed onto the heating element. The time of 18 (hereinafter, also referred to as the film formation time) is preferably 1.0 to 20 seconds, more preferably 1.0 to 8.5 seconds. The pressure in the vacuum chamber during film formation is preferably reduced to, for example, 1.0 to 100 Pa. More preferably 1.4 to 50 Pa.

According to experiments by the inventors of the present invention, an organodecane-based compound other than the organodecane-based compound represented by the formula (Chemical Formula 1) (for example, monomethylnonane, dimethyldecane, trimethylnonane, tetramethyl) is used. When a film formed as a material gas by decane or dimethoxymethyl vinyl decane is subjected to XPS analysis on the surface under the condition (1), no Si peak is observed and a main peak based on SiO, SiC or SiOC is observed. . Further, the BIF of the plastic formed body including the film was less than 3, and it was confirmed that a film having a high gas barrier property could not be obtained with a single gas. Further, if a metal other than Mo, W, Zr, Ta, V, Nb or Hf is used (for example, Ir (铱), Re (鎓), Pt (platinum), Rh (铑), Ti (titanium), Cr ( Chromium)) As the heating element 18, even if the organic decane compound represented by the formula (Chemical Formula 1) is used as the material gas 33, there is a problem that the film formation efficiency is low and the productivity is inferior. Further, when XPS analysis was performed on the surface of the extremely thin film obtained under the condition (1), no Si peak was observed and a main peak based on SiO _{2 was} slightly observed. On the other hand, in the gas barrier plastic molded article of the present embodiment, an organic decane compound represented by the formula (Chemical Formula 1) is used as the material gas 33, and further, a component selected from the group consisting of Mo, W, Zr, Ta, V, Nb is used. The material of one or more of the Hf groups is used as the material of the heating element 18. Therefore, even if the material gas 33 is a single gas, a film having a high gas barrier property of 15 or more BIF can be formed. .

Further, by using a metal ruthenium, a ruthenium-based alloy or tantalum carbide (TaC _x ) as a material containing a ruthenium element, a metal tungsten, a tungsten-based alloy or a tungsten carbide (WC _x ) is used as a material containing a tungsten element, and a metal molybdenum is used. Molybdenum-based alloy or molybdenum carbide (MoC _x ) as a material containing molybdenum or metal ruthenium, ruthenium-based alloy or niobium carbide (HfC _x ) as a material containing niobium, and the catalytic activity of these materials is high Therefore, the raw material gas can be decomposed more efficiently. Further, since the dense film is deposited by efficiently generating the chemical species 34, a film having high gas barrier properties can be formed.

When the heating body CVD method is used, the adhesion between the plastic container 11 and the gas barrier film is very good. When hydrogen gas is introduced from the material gas channel 17, the hydrogen gas is activated by the contact decomposition reaction with the heating element 18, and the surface of the plastic container 11 can be cleaned by the active species. More specifically, a hydrogen abstraction reaction or an etching action of an activated hydrogen H* or a hydrogen radical (atomic hydrogen) H can be expected.

When the NH ₃ gas is introduced from the material gas channel 17 , the surface of the plastic container 11 can be modified and stabilized by using the active species generated by the contact decomposition reaction with the heating element 18 . deal with. More specifically, a crosslinking reaction to the nitrogen-containing functional group of the surface or the polymer chain of the plastic can be expected.

The film thickness of the gas barrier film depends on the material of the heat generating body 18, the pressure of the material gas in the plastic container 11, the flow rate of the supplied gas, the film forming time, etc., but at the same time, the gas barrier property is improved, and the plastic is improved. The adhesion, durability, transparency, and the like of the container 11 are preferably set to 5 to 200 nm. More preferably 10 to 100 nm.

(the end of film formation)

When the film reaches a certain thickness, the supply of the material gas 33 is stopped, and after the gas is again exhausted in the reaction chamber 12, a leak gas (not shown) is introduced to cause a reverse Atmospheric pressure should be reached in chamber 12. Thereafter, the upper chamber 15 is opened to take out the plastic container 11. The gas barrier plastic molded body thus obtained can have a BIF of 6 or more. As a specific example, an oxygen permeability of a 500 ml PET bottle (having a height of 133 mm, a main body outer diameter of 64 mm, a mouth outer diameter of 24.9 mm, a mouth inner diameter of 21.4 mm, a wall thickness of 300 μm, and a resin amount of 29 g) can be obtained. Become 0.0058 cc / container / day or less. The oxygen permeability of a 720 ml PET bottle (height 279 mm, body outer diameter 70 mm, mouth outer diameter 24.9 mm, mouth inner diameter 21.4 mm, wall thickness 509 μm, and resin amount 38 g) becomes 0.0082 cc/ Container / day below.

In this embodiment, a thermal annealing step may also be performed. The thermal annealing step can be performed after the film reaches a certain thickness to stop the supply of the material gas 33 and to exhaust the reaction chamber for a certain period of time. The oxygen permeability of the gas barrier film can be further reduced by the thermal annealing step. The heat generation temperature of the heating element 18 in the thermal annealing step is preferably 1450 ° C or higher, more preferably 1950 ° C or higher. If it is less than 1450 ° C, there is a case where the effect of the thermal annealing treatment cannot be obtained. Further, the upper limit of the heat generation temperature is preferably set to be lower than the softening temperature of the heat generating body 18. The upper limit temperature varies depending on the material of the heating element, and is, for example, 2400 ° C in the case of molybdenum. The heating time of the heating element 18 in the thermal annealing step is preferably 1.0 to 5.0 seconds, more preferably 1.5 to 2.0 seconds. When the thermal annealing step is performed, the energization of the heating element 18 is terminated after the thermal annealing step.

In the method for producing a gas barrier plastic molded article of the present embodiment, it is preferred to have a regeneration step of adding the oxidizing gas to the environment and heating the heat generating body 18 after the film forming step. When an organic decane-based compound is used as a material gas and the film formation step is repeated under the same conditions, the surface of the heating element 18 is carbonized when the temperature is about 30 times, and the gas barrier film 92 is depressurized. Low situation. As a countermeasure, it is preferable to carry out a regeneration step of the heating element 18 that removes the carbon component from the surface of the heating element 18. The regeneration step of the heating element 18 can easily remove the carbon component from the surface of the heating element 18 by the heat generating body 18 in which the oxidizing gas contacts the heat in the vacuum chamber 6 adjusted to a specific pressure, thereby suppressing the continuous film formation. The gas barrier properties of the gas barrier film 92 are lowered. The regeneration step of the heating element 18 is preferably such that the heating element 18 generates heat after the supply of the oxidizing gas. The oxidizing gas is preferably carbon dioxide. The regeneration step of the heating element 18 can be carried out every one film formation step or after a plurality of film formation steps. Further, the step of regenerating the heating element 18 is preferably performed after the film forming step and after the plastic molded body is taken out from the vacuum chamber 6.

In the regeneration step of the heating element 18, the heating temperature of the heating element 18 is preferably 1900 ° C or higher and 2500 ° C or lower. More preferably, it is 2000 ° C or more and 2400 ° C or less. The heating time is preferably 0.5 times or more and 3.0 times or less of the film formation time. Further, when the oxidizing gas to be added is carbon dioxide, the pressure in the vacuum chamber in the regeneration step of the heating element 18 (hereinafter sometimes referred to as the vacuum pressure during regeneration) is preferably 1.3 Pa or more and less than 14 Pa. More preferably, it is 1.4 Pa or more and 13 Pa or less. The partial pressure of the raw material gas 33 in the vacuum chamber at the time of film formation (hereinafter, sometimes referred to as the partial pressure of the material gas at the time of film formation) is preferably more than 1 time and 9 times or less. . When the vacuum pressure at the time of regeneration is less than or equal to the partial pressure of the material gas at the time of film formation, there are cases where the deposition rate of carbide exceeds the removal rate, and when the film is formed continuously on a plurality of formed bodies, the latter half of the film is formed. The gas barrier property is lower than that of the first half film former. Further, if the vacuum pressure at the time of regeneration exceeds 9 times the partial pressure of the material gas at the time of film formation, there are the following cases: carbide removal and heating body The surface of 18 is oxidized, and the oxidized component is mixed into the gas barrier film or consumed by the heat generating body 18 by evaporation. Therefore, the gas barrier property of the latter half of the film formation is lowered at the time of continuous film formation. Further, in the regeneration step of the heating element 18, the supply path of the oxidizing gas into the vacuum chamber 6 may be the same as the supply path of the material gas in the film forming step or may be different from the supply path of the material gas.

Then, regarding the principle of reducing the gas barrier properties of the gas barrier film at the time of repeating the film formation step and the effect of the regeneration step of the heating element 18, the heating element is a metal crucible having a purity of 99.5 mass% and heated to 2000 ° C for 100 consecutive times. The case where the film formation step is repeated is described as an example. Here, the surface of the heating element was analyzed by using a scanning electron microscope (SU1510, manufactured by Hitachi, Ltd.) to observe an elemental composition having a surface depth of 1 μm from the surface of the heating element, and using the energy dispersive X-ray analyzer of the apparatus ( Manufactured by Horiba Manufacturing Co., Ltd., EMAX ENERGY). It was confirmed that the elemental concentration of carbon was less than 1 at.% with respect to film formation, and the maximum increase was 50 at.% after 100 consecutive film formation steps. When this was converted into mass, it was not 0.13 mass% before film formation, and it was 6.2 mass% after repeating film formation process 100 times continuously. The electric resistance of the carbide formed on the surface of the heating element is larger than the electric resistance of the metal crucible forming the central portion of the heating element. Therefore, if the surface of the heating element is carbonized, the surface does not easily rise even when the temperature is applied. As described above, there is a case where it is impossible to ensure a sufficient temperature for the formation of the gas barrier film 92, and a dense film having a high gas barrier property cannot be obtained. When the voltage applied to the heating element 18 is increased and the surface of the heating element is sufficiently heated, the gas barrier film 92 which can improve the gas barrier properties by 10 times or more can be formed in the case of a PET bottle. However, in the mass production step, the application is adjusted in accordance with the sharp resistance change of the surface of the heating element. Voltage control is more complicated. Here, by performing the regeneration step of the heating element 18, it is not necessary to apply complicated control of the voltage, and even if the film forming step is continuously performed, a film having a high gas barrier property can be continuously formed.

A method of forming a gas barrier film on the inner surface of a plastic container has been described. However, when a gas barrier film is formed on the outer surface of the plastic container, for example, the film forming apparatus shown in Fig. 3 of Patent Document 4 can be used. Further, the film forming apparatus is not limited to the apparatus shown in Fig. 2, and various modifications can be made, for example, as shown in Patent Document 2 or 3.

The plastic molded body is described as a plastic container. However, the present invention is not limited thereto, and the plastic molded body may be a film or a sheet.

[Examples]

Hereinafter, the present invention will be described in detail with reference to the embodiments, but the invention is not limited by the examples.

(Example 1)

As a plastic molded body, it is used on the inner surface of a 500 ml PET bottle (having a height of 133 mm, a main body outer diameter of 64 mm, a mouth outer diameter of 24.9 mm, a mouth inner diameter of 21.4 mm, a wall thickness of 300 μm, and a resin amount of 29 g). The film forming apparatus shown in Fig. 2 forms a gas barrier film. The PET bottle was housed in the vacuum chamber 6 and depressurized to 1.0 Pa. Then, as the heating element 18, two molybdenum wires of Φ 0.5 mm and 44 cm in length were used, and a direct current 24 V was applied to the heating element 18 to generate heat to 2000 ° C. Then, the gas flow rate adjuster 24a supplies the vinyl decane as a material gas while adjusting the valve opening degree, and deposits a gas barrier film on the inner surface of the PET bottle. Here, the piping from the gas flow rate adjuster 24a to the gas supply port 16 is composed of a 1/4 inch pipe made of alumina. The flow rate of the material gas was set to 50 sccm. The pressure at the time of film formation (full pressure) was set to 1.4 Pa. The film formation time was set to 6 seconds. At this time, the partial pressure of vinyl decane (the partial pressure of the material gas at the time of film formation) was equal to the pressure at the time of film formation (full pressure), and was 1.4 Pa.

(Example 2)

In the first embodiment, a gas barrier plastic molded body was obtained in accordance with Example 1, except that the direct current applied to the heating element 18 was adjusted and the heat generation temperature was set to 1550 °C.

(Example 3)

In the first embodiment, a gas barrier plastic molded body was obtained in accordance with Example 1, except that the direct current applied to the heating element 18 was adjusted and the heat generation temperature was set to 2,200 °C.

(Example 4)

In the first embodiment, a gas barrier plastic molded article was obtained in the same manner as in Example 1 except that 1,4-dioxane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Example 5)

In the first embodiment, a gas barrier plastic molded article was obtained in the same manner as in Example 1 except that dialkyl acetylene was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Example 6)

In the first embodiment, a gas barrier plastic molded body was obtained in accordance with Example 1 except that a tungsten wire was used instead of the molybdenum wire as the heat generating body 18. The film formation time was set to 6 seconds.

(Example 7)

In the first embodiment, the zirconium wire was used as the heating element 18 instead of the molybdenum wire, and the direct current applied to the heating element 18 was adjusted, and the heat generation temperature was set to 1,700 ° C, and the film formation time was set to 6 seconds. Gas barrier plastic molded body.

(Example 8)

In the first embodiment, a gas barrier plastic molded body was obtained in accordance with Example 1, except that a twisted wire was used instead of the molybdenum wire as the heat generating body 18.

(Example 9)

In the first embodiment, a gas barrier plastic molded body was obtained in accordance with Example 1, except that a twisted wire was used instead of the molybdenum wire as the heat generating body 18, and the film forming time was repeated 5 times for 5 seconds.

(Embodiment 10)

In the first embodiment, the wire is replaced by a tantalum carbide (TaC _x (X = 1, the mass ratio of carbon atoms in TaC _x is 6.2% by mass, and the elemental concentration of carbon atoms in TaC _x is 50 at.%)). The molybdenum wire was used as the heating element 18, and the direct current applied to the heating element 18 was adjusted, and the heat generation temperature was set to 2400 ° C. A film was formed on the surface of the plastic molded body in accordance with Example 1.

(Example 11)

In Example 1, the tungsten carbide (WC _x (X = 1, the mass ratio of carbon atoms in WC _x is 6.1% by mass, the elemental concentration of carbon atoms in WC _x is 50 at.%) is substituted for the line) The molybdenum wire was used as the heating element 18, and the direct current applied to the heating element 18 was adjusted, and the heat generation temperature was set to 2400 ° C. A film was formed on the surface of the plastic molded body in accordance with Example 1.

(Comparative Example 1)

As a plastic molded body, it is used on the inner surface of a 500 ml PET bottle (having a height of 133 mm, a main body outer diameter of 64 mm, a mouth outer diameter of 24.9 mm, a mouth inner diameter of 21.4 mm, a wall thickness of 300 μm, and a resin amount of 29 g). The manufacturing apparatus shown in Fig. 1 of Patent Document 6 forms a film. The PET bottle was housed in an external electrode, and the inside of the external electrode was decompressed to 5 Pa by a vacuum pump. Then, vinyl decane was used as a material gas in the material gas supply pipe, and the flow rate was adjusted to a flow rate of 80 sccm and supplied to the inside of the PET bottle. After the supply of the material gas, electric power is input from the high-frequency power source to the external electrode via the matching device, and a high-frequency voltage of 13.5 MHz and 800 W is applied between the external electrode and the internal electrode to generate plasma. Further, the film was held for 2 seconds in the state where the plasma of the material gas was generated, and a film was formed on the inner surface of the PET bottle.

(Comparative Example 2)

In Example 1, a film was formed on the surface of the plastic molded body according to Example 1, except that monomethyl decane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Comparative Example 3)

In Example 1, a film was formed on the surface of the molded metal body according to Example 1, except that dimethyl decane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Comparative Example 4)

In Example 1, a film was formed on the surface of the molded metal body according to Example 1, except that trimethyldecane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Comparative Example 5)

In Example 1, a film was formed on the surface of the molded metal body according to Example 1, except that tetramethylnonane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Comparative Example 6)

In Example 1, a film was formed on the surface of the molded metal body according to Example 1, except that dimethoxymethylvinyl decane was used instead of vinyl decane as a material gas. The film formation time was set to 6 seconds.

(Comparative Example 7)

In Example 1, a film was formed on the surface of the plastic molded body in accordance with Example 1, except that the twisted wire was used instead of the molybdenum wire as the heat generating body 18. The film formation time was set to 6 seconds.

(Comparative Example 8)

In Example 1, a film was formed on the surface of the plastic molded body in accordance with Example 1, except that the twisted wire was used instead of the molybdenum wire as the heat generating body 18. The film formation time was set to 6 seconds.

(Comparative Example 9)

In the first embodiment, a film was formed on the surface of the plastic molded body in accordance with Example 1, except that a platinum wire was used as the heating element 18 instead of the molybdenum wire, and the direct current applied to the heating element 18 was adjusted and the heat generation temperature was set to 1500 °C. The film formation time was set to 6 seconds.

(Comparative Example 10)

In the first embodiment, a film was formed on the surface of the plastic molded body according to Example 1, except that the twisted wire was used as the heat generating body 18 instead of the molybdenum wire, and the direct current applied to the heat generating body 18 was adjusted and the heat generation temperature was set to 1500 °C. Film formation Set to 6 seconds.

(Comparative Example 11)

In the first embodiment, a film was formed on the surface of the plastic molded body in accordance with Example 1, except that a titanium wire was used as the heating element 18 instead of the molybdenum wire, and a direct current applied to the heating element 18 was adjusted and the heat generation temperature was set to 1500 °C. The film formation time was set to 6 seconds.

(Comparative Example 12)

In Example 1, a film was formed on the surface of the plastic molded body in accordance with Example 1, except that the direct current applied to the heating element 18 was adjusted and the heat generation temperature was set to 1500 °C. The film formation time required to make the film thickness of the film 30 nm was 25 seconds.

The gas barrier plastic molded article and the plastic molded article including the film of the obtained examples and comparative examples were evaluated by the following methods. The evaluation results are shown in Tables 1 to 4.

(XPS analysis)

The surfaces of the films formed in Examples 1 to 8, 10, 11, and Comparative Examples 1 to 4 and 6 were analyzed using an XPS apparatus (type: QUANTERASXM, manufactured by PHI Corporation). The ratio of the constituent elements of the film surface is shown in Table 1. The conditions for XPS analysis are as follows.

X-ray source: monochromatic Al (1486.6 ev)

Detection area: 100 μmΦ

Sputtering conditions: Ar+1.0 kv

Fig. 3 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Example 1 by the condition (1) is separated by waveform analysis. Fig. 4 is a graph showing the spectrum of XPS analysis of the surface of the film of Example 1 under the condition (2). Fig. 5 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Example 4 by the condition (1) is separated by waveform analysis. Fig. 6 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Comparative Example 2 by the condition (1) is separated by waveform analysis. Furthermore, in FIGS. 3, 5, and 6, the bonding state assumed by waveform analysis is: Si1: Si peak (Si-Si bond or Si-H bond), Si2: SiC, SiO ₁ C ₃ Si ₂ O, Si ₃ : SiO ₂ C ₂ , SiO, Si ₄ : SiO ₃ C ₁ , Si ₂ O ₃ , Si ₅ : SiO ₂ .

In the first embodiment, as shown in FIG. 3, a peak is observed at the peak position of the bonding energy of Si and Si under the condition (1), as shown in FIG. 4, under the condition (2) in Si and Si. No peaks were observed at the peak of the bond energy. From this, it can be presumed that the film of Example 1 has a Si-H bond. Furthermore, other embodiments also obtain the same peak. Further, it can be confirmed from Fig. 3 that Si1 (Si peak) is the main peak in the peak of Example 1. As shown in FIG. 5, it can be confirmed that in Embodiment 4 It is the main peak of Si1 (Si wave peak).

On the other hand, in Comparative Example 2, as shown in Fig. 6, under the condition (1), no peak was observed at the peak position of the bonding energy of Si and Si, but in SiC, SiOC, SiO _x or SiO _{2 .} A peak is observed at the position where the peak appears. Further, it can be confirmed from Fig. 6 that Si3 is the main peak in the peak of Comparative Example 2. Further, Comparative Examples 1 and 3 to 8 did not have Si1, and in the comparative example 1, Si2 was used as the main peak, Si3 in Comparative Examples 3 to 6, and Si5 in Comparative Examples 7 to 11.

(Element ratio of film analyzed by RBS)

The films formed in Examples 1 to 8 were analyzed using a high-resolution RBS apparatus (type: HRBS500, manufactured by Kobe Steel Co., Ltd.). The ratio of the constituent elements of the film is shown in Table 2.

(film thickness)

The film thickness was measured using a stylus profiler (type: α-Step, manufactured by KLA-Tencor Co., Ltd.). The evaluation results are shown in Table 3.

(oxygen permeability)

Oxygen permeability was measured using an oxygen permeability measuring apparatus (type: Oxtran 2/20, manufactured by Modern Control Co., Ltd.) under the conditions of 23 ° C and 90% RH, and was adjusted from the start of measurement for 24 hours from the start of the measurement. After 72 hours, the value. For reference, the oxygen permeability of the PET bottle before film formation was measured, and it is shown in the table as an unfilmed bottle. The evaluation results are shown in Table 3.

(BIF)

BIF is the value of the oxygen permeability of the unformed bottle in the number 4 as the oxygen permeability of the plastic formed body without the film, which is obtained in the examples or the comparative examples. The value of the oxygen permeability of the plastic container was calculated as the oxygen permeability of the gas barrier plastic molded body. The evaluation results are shown in Table 3.

(film density)

The film density was stirred in 100 ml of various concentrations of potassium carbonate aqueous solution to visually observe the ups and downs after 15 minutes. A commercially available oil-based pen ink was applied to a PET bottle, and a film of 50 μm was formed thereon according to the conditions of Examples 1, 4 and 5, and then taken out from the PET bottle using a cotton swab impregnated with ethanol. Diaphragm. The film floating on the surface of the aqueous solution of potassium carbonate was judged to have a density smaller than the density of the aqueous solution (○), and the film deposited on the bottom surface of the aqueous solution of potassium carbonate was judged to have a density greater than the density (×) of the aqueous solution, and suspended in potassium carbonate. The diaphragm between the water surface and the bottom surface of the aqueous solution was judged to have a density equal to the density of the aqueous solution (Δ), and the range determined by Δ was taken as the range of the density. The density and evaluation results of various concentrations are shown in Table 4.

As shown in Tables 1 to 3, the gas barrier films of Examples 1 to 11 have a Si-H bond in the film and include a Si-containing layer having a Si content of 40.1% or more, so that oxygen permeation can be confirmed. A film having a small degree of value, a BIF of 6 or more, and a high gas barrier property using a single raw material gas.

On the other hand, in Comparative Example 1, since the film was formed by the plasma CVD method, the Si content in the film was low and the gas barrier property was inferior. In the comparative example using a gas other than the formula (Chemical Formula 1) as a material gas, the Si content in the film was low and the gas barrier property was inferior. In Comparative Examples 7 to 11, since Mo, W, Zr, Ta, V, Nb, or Hf was used as the heating element, the film formation efficiency was poor and the gas barrier property was inferior. In Comparative Example 12, since the heat generation temperature of the heat generating body was low, the film forming efficiency was poor and the gas barrier property was inferior.

Then, a test for confirming the effect of the regeneration step of the heating element was performed.

(Embodiment 12)

The film formation was carried out 100 times in accordance with Example 8, and the regeneration step of the heating element was carried out every time the film formation was completed. In the regeneration step, when the pressure in the vacuum chamber 6 reaches a vacuum pressure of 1.0 Pa, CO ₂ is supplied as an oxidizing gas to the vacuum chamber 6, and the vacuum pressure is made 12.5 Pa (the material gas at the time of film formation) The heating element 18 was heated at 2000 ° C for 6 seconds at a pressure of 9.0 times the pressure of 1.4 Pa.

(Example 13)

Film formation was carried out 100 times in accordance with Example 8, and a heating element regeneration step was carried out every 10 times of film formation. Each of the regeneration steps was carried out under the same conditions as in Example 12 except that the heating time of the heating element was 60 seconds.

(Example 14)

Film formation was carried out 100 times in accordance with Example 10, and the regeneration step of the heating element was carried out every time the film formation was completed. Each regeneration step was carried out under the same conditions as in Example 12.

(Example 15)

Film formation was carried out 100 times in accordance with Example 10, and a heating element regeneration step was carried out every 10 times of film formation. Each regeneration step was carried out under the same conditions as in Example 13.

(Embodiment 16)

In the embodiment 12, the same as in the embodiment 12 except that the CO _{2 is} supplied to the vacuum chamber 6 so that the vacuum pressure becomes 1.4 Pa (the vacuum pressure of 1.0 Pa of the partial pressure of the material gas at the time of film formation). The conditions for the regeneration of the heating element are performed.

(Example 17)

In the embodiment 12, the same as in the embodiment 12 except that the CO _{2 is} supplied to the vacuum chamber 6 so that the vacuum pressure becomes 1.3 Pa (the vacuum pressure of 0.93 times the partial pressure of the material gas at the time of film formation is 0.93). The conditions for the regeneration of the heating element are performed.

(Reference example 1)

In Example 12, except that the CO ₂ is supplied to the vacuum chamber the vacuum pressure became 6 than 14.0 Pa (when the film-forming raw material gas partial pressure of 10.0 times the vacuum pressure of 1.4 Pa), the same as in Example 12 The conditions for the regeneration of the heating element are performed.

(Reference example 2)

Film formation was carried out 100 times in accordance with Example 8, and the regeneration step of the heating element was not performed.

(Reference Example 3)

Film formation was carried out 100 times in accordance with Example 10, and the regeneration step of the heating element was not performed.

(BIF measurement)

With respect to Examples 20 to 25 and Reference Examples 1 to 3, the BIF of the first and 100th film formation was measured. The measurement method of BIF is the method described in "gas barrier evaluation - BIF". The criteria for determining the gas barrier properties are as follows. The measurement results of BIF are shown in Fig. 7.

Judging criteria for gas barrier evaluation: BIF is 8 or more: practical level

BIF is above 5 and not up to 8: practical level

BIF is 2 or more and less than 5: minimum practical level

BIF does not reach 2: not practical level.

As can be seen from Fig. 7, the BIFs of the first and the 100th times in the examples 12 to 17 are practical levels. In particular, in each of Examples 12 to 16, the gas barrier properties were not significantly different between the first and the 100th film formation, and the BIF of the 100th time was 8 or more. In Example 17, since the vacuum pressure at the time of regeneration was lower than the vacuum pressure in the vacuum chamber at the time of film formation, the BIF of the 100th time was 3.6, but the practical level was maintained. On the other hand, in Reference Example 1 to Reference Example 3, the gas barrier properties were good at the time of the first film formation, but the gas barrier properties were largely lowered at the time of the 100th film formation. Although the regeneration step was carried out in Reference Example 1, it is considered that the vacuum pressure at the time of regeneration is too high, so that the surface of the heating element is oxidized to lower the gas barrier properties after continuous film formation. From the above, it was confirmed that the film formation adaptability was improved by performing the regeneration step.

[Industrial availability]

The gas barrier plastic molded article of the present invention is suitable for use in packaging materials. Moreover, the gas barrier container including the gas barrier plastic molded article of the present invention is suitable for use in a beverage container for water, tea beverage, refreshing beverage, carbonated beverage, fruit juice beverage, and the like.

6‧‧‧vacuum chamber

8‧‧‧Vacuum valve

11‧‧‧Plastic containers

12‧‧‧Reaction room

13‧‧‧ lower chamber

14‧‧‧O-ring

15‧‧‧Upper chamber

16‧‧‧ gas supply port

17‧‧‧Material gas flow path

17x‧‧‧ gas ejection hole

18‧‧‧heating body

19‧‧‧Wiring

20‧‧‧heating power supply

21‧‧‧ mouth of plastic container

22‧‧‧Exhaust pipe

23‧‧‧Material gas supply pipe

24a, 24b‧‧‧ flow regulator

25a, 25b, 25c‧‧‧ valves

26a, 26b‧‧‧ Connections

27‧‧‧Cooling water flow path

28‧‧‧ Inside the vacuum chamber

29‧‧‧Cooling device

30‧‧‧Case including transparent body

33‧‧‧Material gases

34‧‧‧Chemical species

35‧‧‧Insulated ceramic components

40a, 40b‧‧‧ raw material tank

41a, 41b‧‧‧ starting materials

90‧‧‧ gas barrier plastic molded body

91‧‧‧plastic molded body

92‧‧‧ gas barrier film

100‧‧‧ film forming device

Fig. 1 is a cross-sectional view showing a basic configuration of a gas barrier plastic molded article of the present embodiment.

Fig. 2 is a schematic view showing one form of a film forming apparatus.

Fig. 3 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Example 1 by the condition (1) is separated by waveform analysis.

Figure 4 is a graph showing the XPS analysis of the film surface of Example 1 under the condition (2). The map of the spectrum.

Fig. 5 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Example 4 by the condition (1) is separated by waveform analysis.

Fig. 6 is a view in which the peak observed in the spectrum of XPS analysis of the film surface of Comparative Example 2 by the condition (1) is separated by waveform analysis.

Fig. 7 is a view showing the first and the 100th BIF of the film formation in the confirmation test of the heating step of the heating element.

90‧‧‧ gas barrier plastic molded body

91‧‧‧plastic molded body

92‧‧‧ gas barrier film

Claims (2)

A method for producing a gas barrier plastic molded body, comprising the steps of forming a film by contacting a raw material gas with a heat generating body that generates heat, decomposing the material gas to form a chemical species, and causing the chemical species to reach the surface of the plastic molded body. Thus, a gas barrier film is formed, which is characterized in that vinyl hydride (H ₃ SiC ₂ H ₃ ), dialkyl acetylene (H ₃ SiC ₂ SiH ₃ ) or 2-aminoethyl decane (H ₃ SiC ₂ H) is used. ₄ NH ₂ ) as the material gas, and a material containing one or two or more metal elements selected from the group consisting of Mo, W, Zr, Ta, V, Nb, and Hf is used as the heat generating body, and the heat is generated. The heating temperature of the body is set to 1550~2400 °C. The method for producing a gas barrier plastic molded body according to claim 1, wherein the heating element is made of a metal ruthenium, a ruthenium-based alloy or tantalum carbide, a metal tungsten, a tungsten-based alloy or a tungsten carbide, and a metal molybdenum or a molybdenum-based alloy is used. Or molybdenum carbide, or use metal ruthenium, ruthenium based alloy or tantalum carbide.