JP2012188700A - Gas barrier plastic molding and method for producing the same - Google Patents

Abstract

An object of the present invention is to provide a method of forming a gas barrier thin film having high adhesion (particularly water resistance) with a plastic molded body on the surface of the plastic molded body using a heating element CVD method. It is.
A method for producing a gas barrier plastic molded body 90 according to the present invention includes forming a gas barrier thin film 92 containing Al and O as constituent elements on a surface of a plastic molded body 91 by a heating element CVD method. In the method for producing a plastic molded body, hydrogen gas is supplied into the vacuum chamber 6 containing the plastic molded body to reduce the surface of the plastic molded body, and an Al source material gas is supplied. A film forming process for forming a gas barrier thin film by bringing an Al source material gas into contact with a heated heating element, decomposing the Al source material gas to generate chemical species, and reaching the surface of the plastic molded body And have.
[Selection] Figure 2

Description

  The present invention relates to a gas barrier plastic molding and a method for producing the same.

  Plastics have the advantages of transparency, lightness, impact resistance, corrosion resistance, and processability, are inexpensive, and can be used for high-mix low-volume production, so they can be used for packaging food, beverages, pharmaceuticals, cosmetics, etc. Suitable as packaging material. However, compared with other packaging materials such as metal or glass, plastic has a problem that it has a low gas barrier property and is not suitable as a packaging material for contents that hate oxidation or contents containing gas such as beer. . Therefore, a gas barrier property is imparted by forming a thin film containing a metal oxide on the surface of a plastic molded body. In a plastic molded body (hereinafter also referred to as a gas barrier plastic molded body) having a thin film having a gas barrier property (hereinafter sometimes referred to as a gas barrier thin film), the adhesion between the substrate and the thin film can be improved. It is being considered.

Conventionally, regarding a technique for forming a thin film on a base material, a technique for improving the adhesion between the base material and the thin film has been proposed. For example, in a technique for producing a film mainly composed of diamond by introducing hydrogen, carbon dioxide gas, and carbonized gas into a plasma generation space using a plasma chemical vapor deposition (CVD) method, the film is generated under plasma conditions. A technique for improving adhesion by reducing and removing natural oxide on the surface of a substrate using carbon monoxide as a reducing agent has been disclosed (see, for example, Patent Document 1). As a technique for improving the adhesion between the substrate and the thin film, a natural oxide film is formed by a reduction reaction using a reducing gas containing at least one of NF gas, NF ₃ gas, NH ₃ gas, and H ₂ gas. A dry cleaning process to be removed is disclosed (for example, see Patent Document 2). By bringing hydrogen or a hydrogen-containing gas into contact with a high-temperature catalyst body, a large amount of high-temperature hydrogen-based active species is generated, and this is sprayed on a carbon film formed on the substrate, thereby causing the action of the hydrogen-based active species. A technique is disclosed in which an amorphous component is selectively etched and carbon ultrafine particles having a diamond structure are reliably and stably scattered on the surface of a carbon film or a substrate (for example, a glass substrate) (for example, Patent Documents). 3). Disclosed is a technique for cleaning the surface without damaging the resonator end face by exposing the resonator end face to a radicalized atmosphere by contacting a gas containing nitrogen with the heated catalyst wire and thermally decomposing it. (For example, refer to Patent Document 4). Furthermore, Patent Document 4 discloses that by using hydrogen, there is a cleaning effect in which Si, an organic silicon compound, and the like attached to the surface are etched by the reducing action of radicalized hydrogen atoms. Further, it is disclosed that the adhesion between the base sheet and the conductive coat layer is remarkably improved by providing an anchor coat layer for adhesion between the base sheet made of a resin film and the conductive coat layer. (For example, see Patent Document 5).

Japanese Patent Laid-Open No. 2-48494 JP 2008-103370 A JP 2002-293687 A JP 2010-225727 A JP 2005-190932 A JP 2008-127053 A

  In the method of forming a thin film by the plasma CVD method, the plasma damages the film surface when forming the thin film, and the denseness of the thin film tends to be impaired. In addition, since the raw material gas is made into plasma by high frequency including microwaves and reacted on the surface of the plastic container to form a thin film, a high frequency power source and a high frequency power matching device are always required, which increases the cost of the device. There is a problem that it must be.

  A method in which a raw material gas is brought into contact with a heated heating element for decomposition and the generated chemical species is directly or in a gas phase after being subjected to a reaction process, and then deposited as a thin film on a substrate, that is, heating element CVD method, Cat A CVD method called a CVD method or a hot wire CVD method (hereinafter referred to as a heating element CVD method in this specification) is a thin film having a dense and high gas barrier property by solving the problems of the plasma CVD method described above. Can be formed by a film forming apparatus that is simpler and lower in cost than a plasma CVD film forming apparatus.

  However, according to an experiment conducted by the present inventors, a plastic bottle was used as a plastic molded body by a heating element CVD method, and an aluminum oxide (AlOx) and a titanium oxide (TiOx) were formed on the inner surface of the plastic bottle. When a thin film containing a metal oxide such as) was formed and water was filled into a plastic bottle whose inner surface was covered with the thin film containing the metal oxide, the film was peeled in one day.

  Up to now, although there has been an examination case of forming a thin film containing a metal oxide such as AlOx or TiOx by using a heating element CVD method, the heating element has high adhesion (particularly water resistance) with a plastic molding. The knowledge about the film-forming method which can be ensured using CVD method is not disclosed. In particular, a thin film containing AlOx is known to have a high gas barrier property, and it is desired to realize high adhesion with a substrate.

  An object of the present invention is to provide a method of forming a gas barrier thin film having high adhesion (particularly water resistance) with a plastic molded body on the surface of the plastic molded body using a heating element CVD method.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have specifically improved the adhesion of the thin film containing AlOx by reducing the surface of the plastic molded body with hydrogen gas. As a result, the present invention has been completed.

  The method for producing a gas barrier plastic molded body according to the present invention comprises forming a gas barrier thin film containing aluminum (Al) and oxygen (O) as constituent elements on the surface of a plastic molded body by a heating element CVD method. In the method for producing a molded body, a hydrogen treatment step of reducing the surface of the plastic molded body by supplying hydrogen gas into the vacuum chamber that houses the plastic molded body, and a vacuum chamber that houses the plastic molded body An Al source raw material gas is supplied into the interior of the substrate, the Al source raw material gas is brought into contact with a heating element that generates heat, the Al source raw material gas is decomposed to generate chemical species, and the surface of the plastic molded body is formed. And a film forming step of forming the gas barrier thin film by reaching the chemical species.

  In the method for producing a gas barrier plastic molded body according to the present invention, it is preferable that the hydrogen treatment step includes a step of bringing hydrogen gas into contact with a heating element that generates heat. The adhesion between the base material and the gas barrier thin film can be further increased.

  In the method for producing a gas barrier plastic molded body according to the present invention, it is preferable that the hydrogen treatment step includes a step of simultaneously supplying hydrogen gas and the Al source material gas. The adhesion between the base material and the gas barrier thin film can be further increased.

  In the method for producing a gas barrier plastic molded article according to the present invention, the plastic molded article includes a film, a sheet, or a container.

  The gas barrier plastic molding according to the present invention is formed by the method for producing a gas barrier plastic molding according to the present invention.

  The present invention can provide a method of forming a gas barrier thin film having high adhesion (particularly water resistance) with a plastic molded body on the surface of the plastic molded body using a heating element CVD method.

It is the schematic which shows one form of the film-forming apparatus. It is sectional drawing which shows an example of the gas barrier plastic molding which concerns on this embodiment.

  Next, the present invention will be described in detail with reference to embodiments, but the present invention is not construed as being limited to these descriptions. As long as the effect of the present invention is exhibited, the embodiment may be variously modified.

  First, a film forming apparatus capable of forming a gas barrier thin film on the surface of a plastic molded body will be described. FIG. 1 is a schematic view showing an embodiment of a film forming apparatus. The film forming apparatus shown in FIG. 1 is an apparatus that can form a thin film on the inner surface of a container when the plastic molding is a container.

  The film forming apparatus 100 shown in FIG. 1 is inserted into and removed from a vacuum chamber 6 that houses a plastic container 11 as a plastic molded body, an exhaust pump (not shown) that evacuates the vacuum chamber 6, and the plastic container 11. A source gas supply pipe 23 formed of an insulating and heat-resistant material, which is arranged in a possible manner and supplies a source gas into the plastic container 11, a heating element 18 supported by the source gas supply pipe 23, and heat generation And a heater power supply 20 that energizes the body 18 to generate heat.

  The vacuum chamber 6 has a space for accommodating the plastic container 11 therein, and the space serves as a reaction chamber 12 for forming a thin film. The vacuum chamber 6 includes a lower chamber 13 and an upper chamber 15 that is detachably attached 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 an upper and lower drive mechanism (not shown) and moves up and down as the plastic container 11 is carried in and out. The internal space of the lower chamber 13 is formed to be slightly larger than the outer shape of the plastic container 11 accommodated therein.

  The inside of the vacuum chamber 6, particularly the inside of the lower chamber 13, has an inner surface 28 that is a black inner wall or an inner surface that has a surface roughness (Rmax) in order to prevent reflection of light emitted as the heating element 18 generates heat. ) It is preferable to have irregularities of 0.5 μm or more. The surface roughness (Rmax) is measured using, for example, a surface roughness measuring device (DEKTAX 3 manufactured by ULVAC TECHNO CORPORATION). In order to make the inner surface 28 a black inner wall, there are a plating process such as black nickel plating and black chrome plating, a chemical film treatment such as radiant and black dyeing, or a method of coloring by applying a black paint. Furthermore, it is preferable to provide a cooling means 29 such as a cooling pipe through which the cooling water flows inside or outside the vacuum chamber 6 to prevent the temperature of the lower chamber 13 from rising. Among the vacuum chambers 6, the lower chamber 13 is particularly targeted because when the heating element 18 is inserted into the plastic container 11, the vacuum chamber 6 is in a state of being accommodated in the inner space of the lower chamber 13. By preventing light reflection and cooling the vacuum chamber 6, the temperature rise of the plastic container 11 and the accompanying thermal deformation can be suppressed. Furthermore, if a chamber 30 made of a transparent material through which the emitted light generated from the energized heating element 18 can pass, for example, a glass chamber, is disposed inside the lower chamber 13, the temperature of the glass chamber in contact with the plastic container 11 rises. Therefore, the thermal influence on the plastic container 11 can be further reduced.

  The source gas supply pipe 23 is supported so as to hang downward at the center of the inner ceiling surface of the upper chamber 15. The source gas supply pipe 23 is supplied with the Al source material gas 33 and the hydrogen gas, and, if necessary, the carrier gas through the flow rate regulators 24a, 24b or 24c and the valves 25a, 25b or 25c. When the material used as the Al source material gas 33 is a liquid, the Al source material gas 33 can be supplied by a bubbling method. That is, the bubbling gas is supplied from the cylinder 42a to the starting material 41a accommodated in the material tank 40a while controlling the flow rate with the flow rate controller 24a, and the vapor of the starting material 41a is generated and supplied as the Al source material gas 33. . Hydrogen gas is accommodated in the cylinder 42b and supplied while the flow rate is controlled by the flow rate regulator 24b. The carrier gas used as necessary is accommodated in the cylinder 42c and supplied while the flow rate is controlled by the flow rate regulator 24c. In the film forming apparatus shown in FIG. 1, when the substance used as the Al source material gas 33 supplied through the valve 25a is a gas, the Al source material gas 33 is supplied to the cylinder 42a without providing the material tank 40a. It is only necessary to modify the form in which the liquid is charged and supplied while controlling the flow rate with the flow regulator 24a. Further, a method is adopted in which the liquid Al source material gas 33 is vaporized in the cylinder 42a and the Al source material gas 33 filled in the head space in the cylinder 42a is supplied by opening the valve 25a. Also good.

  The source gas supply pipe 23 preferably has a cooling pipe and is integrally formed. As a structure of such a source gas supply pipe 23, for example, there is a double pipe structure. In the source gas supply pipe 23, the inner pipe line of the double pipe is a source gas channel 17, one end of which is connected to the gas supply port 16 provided in the upper chamber 15, and the other end is a gas blowout. It is a hole 17x. As a result, the Al source material gas 33 and the hydrogen gas are blown out from the gas blowing holes 17 x at the tip of the material gas flow path 17 connected to the gas supply port 16. On the other hand, the outer pipe line of the double pipe is a cooling water flow path 27 for cooling the source gas supply pipe 23, and plays a role as a cooling pipe. Then, when the heating element 18 generates heat by energization, for example, the temperature of the source gas channel 17 rises. In order to prevent this, the cooling water circulates in the cooling water passage 27. That is, at one end of the cooling water flow path 27, cooling water is supplied from a cooling water supply means (not shown) connected to the upper chamber 15, and at the same time, the cooled cooling water is returned to the cooling water supply means. On the other hand, the other end of the cooling water passage 27 is sealed in the vicinity of the gas blowing hole 17x, and here, the cooling water is folded back. The entire raw material gas supply pipe 23 is cooled by the cooling water passage 27. By cooling, the thermal influence on the plastic container 11 can be reduced. Therefore, the material of the source gas supply pipe 23 is preferably an insulator and has a high thermal conductivity. For example, a ceramic tube made of a material mainly containing aluminum nitride, silicon carbide, silicon nitride, or aluminum oxide, or a surface made of a material mainly containing aluminum nitride, silicon carbide, silicon nitride, or aluminum oxide Is preferably a coated metal tube. The heating element can be stably energized, has durability, and can efficiently exhaust heat generated by the heating element by heat conduction.

  The source gas supply pipe 23 may be configured as follows as another form (not shown). That is, the source gas supply pipe is a double pipe, the outer pipe is used as a source gas flow path, and a hole, preferably a plurality of holes, is formed in the side wall of the outer pipe. On the other hand, the inner pipe of the double pipe of the source gas supply pipe is formed by a dense pipe, and the cooling water flows as a cooling water flow path. The heating element is wired along the side wall of the source gas supply pipe, but the Al source source gas 33 that has passed through the hole provided in the side wall of the outer pipe comes into contact with the heating element in the portion along the side wall so Species 34 can be generated.

  If the gas blowing hole 17 x is too far from the bottom of the plastic container 11, it is difficult to form a thin film inside the plastic container 11. In the present embodiment, the length of the source gas supply pipe 23 is preferably formed such that the distance L1 from the gas blowing 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 thin 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, it may be difficult to form a thin film on the bottom of the plastic container 11. If the distance is smaller than 5 mm, it may be difficult to blow out the Al source material gas 33 and the hydrogen gas, or the film thickness distribution may be uneven. This fact can be grasped theoretically. In the case of a 500 ml container, since the container body diameter is 6.4 cm and the mean free path λ = 0.68 / Pa [cm] of air at room temperature, the molecular flow pressure <0.106 Pa and the viscous flow pressure> 10. 6 Pa, the intermediate flow is 0.106 Pa <pressure <10.6 Pa. At a gas pressure of 5 to 100 Pa during film formation, the gas flow changes from an intermediate flow to a viscous flow, and there is an optimum condition for the distance between the gas blowing hole 17x and the bottom of the plastic container 11.

  The heating element 18 promotes the decomposition of the Al source material gas 33 in the heating element CVD method. In addition, the hydrogen gas is decomposed to generate hydrogen radicals. The material of the heating element 18 is not particularly limited, but C, W, Ta, Ti, Hf, V, Cr, Mo, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, It is preferably composed of a material containing one or more metal elements selected from the group of Pt. By having conductivity, it becomes possible to generate heat by energization. The heating element 18 is formed in a wiring shape, and is connected to one end of the heating element 18 at a connection portion 26 a provided below the fixed portion in the upper chamber 15 of the source gas supply pipe 23 and serving as a connection point between the wiring 19 and the heating element 18. Is connected. And it is supported with the insulating ceramic member 35 provided in the gas blowing hole 17x which is a front-end | tip part. Further, the other end of the heating element 18 is connected to the connecting portion 26b. As described above, since the heating element 18 is supported along the side surface of the source gas supply pipe 23, the heating element 18 is arranged so as to be positioned substantially on the main axis of the internal space of the lower chamber 13. Although FIG. 1 shows the case where the heating element 18 is arranged along the periphery of the source gas supply pipe 23 so as to be parallel to the axis of the source gas supply pipe 23, the source gas supply pipe starts from the connection portion 26a. 23 may be spirally wound around the side surface of 23 and supported by the insulating ceramic member 35 fixed in the vicinity of the gas blowing hole 17x, and then folded back toward the connecting portion 26b. Here, the heating element 18 is fixed to the source gas supply pipe 23 by being hooked on the insulating ceramic member 35. FIG. 1 shows the case where the heating element 18 is disposed on the outlet side of the gas blowing hole 17x in the vicinity of the gas blowing hole 17x of the source gas supply pipe 23. As a result, the Al source material gas 33 blown out from the gas blowing holes 17x can easily come into contact with the heating element 18, so that the Al source material gas 33 can be efficiently activated. Here, it is preferable that the heating element 18 be disposed slightly away from the side surface of the source gas supply pipe 23. This is to prevent a rapid temperature rise of the source gas supply pipe 23. Moreover, the opportunity of contact with the Al source material gas 33 blown out from the gas blowing holes 17x and the Al source material gas 33 in the reaction chamber 12 can be increased. The outer diameter of the source gas supply pipe 23 including the heating element 18 needs to be smaller than the inner diameter of the mouth portion 21 of the plastic container. This is because the source gas supply pipe 23 including the heating element 18 is inserted from the mouth portion 21 of the plastic container. Therefore, if the heating element 18 is separated from the surface of the raw material gas supply pipe 23 more than necessary, it will be easy to contact when the raw material gas supply pipe 23 is inserted from the mouth portion 21 of the plastic container. The lateral width of the heating element 18 is suitably 10 mm or more and (inner diameter of the mouth part −6) mm or less in consideration of positional deviation when inserted from the mouth part 21 of the plastic container. For example, the inner diameter of the mouth portion 21 is approximately 21.7 to 39.8 mm.

  The heating element 18 can generate heat by energization, for example. In the apparatus shown in FIG. 1, a heater power source 20 is connected to the heating element 18 via connection portions 26 a and 26 b and wiring 19. The heater 18 generates heat when electricity is supplied to the heater 18 by the heater power source 20. The present invention is not limited to the heating method of the heating element 18.

  Further, since the stretch ratio at the time of molding of the plastic container 11 is small from the mouth portion 21 of the plastic container to the shoulder of the container, if the heating element 18 that generates heat at a high temperature is disposed nearby, it is likely to be deformed by heat. According to the experiment, the shoulder portion of the plastic container 11 is thermally deformed unless the positions of the connection portions 26a and 26b, which are the connection points between the wiring 19 and the heating element 18, are 10 mm or more away from the lower end of the mouth portion 21 of the plastic container. When the thickness exceeded 50 mm, it was difficult to form a thin film on the shoulder portion of the plastic container 11. Therefore, the heating element 18 is preferably arranged so that the upper end thereof is located 10 to 50 mm below the lower end of the mouth portion 21 of the plastic container. That is, it is preferable that the distance L2 between the connection portions 26a and 26b and the lower end of the mouth portion 21 is 10 to 50 mm. Thermal deformation of the shoulder portion of the container can be suppressed.

  An exhaust pipe 22 communicates with the internal space of the upper chamber 15 via a vacuum valve 8 so that air in the reaction chamber 12 inside the vacuum chamber 6 is exhausted by an exhaust pump (not shown). .

  The film formation apparatus shown in FIG. 1 does not require a high-frequency power source, and the apparatus is cheaper than a plasma CVD apparatus. The apparatus for forming the gas barrier thin film on the inner surface of the plastic container has been described. To form the gas barrier thin film on the outer surface of the plastic container, for example, the film forming apparatus shown in FIG. Can do. Further, the film forming apparatus is not limited to the apparatus shown in FIG. 1, and various modifications can be made as shown in Patent Document 6, for example.

  Next, the manufacturing method of the gas barrier plastic molding which concerns on this embodiment is demonstrated, referring FIG. FIG. 2 is a cross-sectional view showing an example of a gas barrier plastic molding according to the present embodiment. In the method for manufacturing a gas barrier plastic molded body 90 according to the present embodiment, a gas barrier thin film 92 containing aluminum (Al) and oxygen (O) as constituent elements is formed on the surface of the plastic molded body 91 by a heating element CVD method. In the method for producing a gas barrier plastic molded body, hydrogen gas is supplied into the vacuum chamber 6 in which the plastic molded body 91 (the plastic container 11 in FIG. 1) is housed, and the surface of the plastic molded body 91 (FIG. 1). Then, the hydrogen treatment process for reducing the inner surface of the plastic container 11 and the heat generated when the Al source material gas 33 is heated by supplying the Al source material gas 33 into the vacuum chamber 6 containing the plastic molded body 91. In contact with the body 18, the Al source material gas 33 is decomposed to generate chemical species 34, and a plastic molded body 91 is formed. By reaching the chemical species 34 to the surface, and a film forming step of forming a gas barrier thin film 92.

  The method for producing a gas barrier plastic molded body has a process of mounting the plastic molded body on the film forming apparatus and a process of adjusting the pressure in the reaction chamber during the hydrogen treatment process, which will be described in order.

<Attaching process of plastic molding to film forming device>
First, a vent (not shown) is opened to open the vacuum chamber 6 to the atmosphere. In the reaction chamber 12, with the upper chamber 15 removed, a plastic container 11 as a plastic molded body 91 is inserted and accommodated from the upper opening of the lower chamber 13. Thereafter, the positioned upper chamber 15 is lowered, and the source gas supply pipe 23 attached to the upper chamber 15 and the heating element 18 fixed thereto are inserted into the plastic container 11 from the opening 21 of the plastic container. Then, the upper chamber 15 is brought into contact with the lower chamber 13 via the O-ring 14, whereby the reaction chamber 12 is made a sealed space. At this time, the distance 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 distance between the inner wall surface of the plastic container 11 and the heating element 18 is also substantially uniform. It is kept in.

  In the manufacturing method of the gas barrier plastic molding according to the present embodiment, the plastic molding 91 includes a film, a sheet, or a container. When the plastic molded body 91 is a container, the method for forming the gas barrier thin film 92 on the inner surface or the outer surface of the container is as described above. When the plastic molded body is a film or a sheet, for example, the reaction chamber 12 is formed into a cylindrical shape, and the gas barrier thin film 92 is formed on the surface of the film or the sheet by fixing the film or sheet along the inner wall thereof. Can do. Moreover, you may carry out the deformation | transformation which provides the winding apparatus which consists of the roll which rolls out the roll-shaped film or sheet in the vacuum chamber 6, and the roll which winds up the film or sheet in which the thin film was formed.

  Examples of the resin constituting the plastic molded body 91 include polyethylene terephthalate resin (PET), polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene resin, polypropylene resin (PP), and cycloolefin copolymer resin (COC, cyclic olefin copolymer). , Ionomer 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, polyamideimide resin , Polyacetal resin, polycarbonate resin, polysulfone resin, or tetrafluoroethylene resin, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene resin . One of these may be used as a single layer, or two or more may be used as a laminate, but a single layer is preferable in terms of productivity. The type of resin is more preferably PET.

  The thickness of the plastic molded body 91 can be appropriately set according to the purpose and application, and is not particularly limited. When the plastic molded body 91 is a container such as a beverage bottle, for example, the thickness of the bottle is preferably 50 to 500 μm, and more preferably 100 to 350 μm. Moreover, when it is a film which comprises a packaging bag, it is preferable that the thickness of a film is 3-300 micrometers, More preferably, it is 10-100 micrometers. When the plastic molded body 91 is a substrate of a flat panel display such as electronic paper or organic EL, the thickness of the film is preferably 25 to 200 μm, and more preferably 50 to 100 μm. Moreover, when it is a sheet | seat for forming a container, it is preferable that the thickness of a sheet | seat is 50-500 micrometers, More preferably, it is 100-350 micrometers. When the plastic molded body 91 is a container, the gas barrier thin film 92 is provided on one 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 thin film 92 is provided on one side or both sides.

<Pressure adjustment process>
Next, after closing the vent (not shown), the exhaust pump (not shown) is operated and the vacuum valve 8 is opened, whereby the air in the reaction chamber 12 is exhausted. 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 evacuated and evacuated. That is, the entire reaction chamber 12 is exhausted. In preparation for the subsequent hydrogen treatment step, the pressure in the vacuum chamber 6 is preferably reduced until it reaches, for example, 1.0 to 100 Pa. More preferably, it is 1.4-50 Pa. If it is less than 1.0 Pa, exhaust may take time. Moreover, when it exceeds 100 Pa, impurities may increase in the plastic container 11 and high barrier properties may not be imparted.

<Hydrogen treatment process>
(Hydrogen gas supply)
Hydrogen gas is supplied into the vacuum chamber 6 adjusted to a predetermined pressure while being controlled to a predetermined flow rate by the flow rate regulator 24c. The flow rate of hydrogen gas is preferably 10 to 200 sccm. More preferably, it is 25-100 sccm, Most preferably, it is 30-50 sccm.

(Hydrogen treatment)
When hydrogen gas is supplied, the inside of the vacuum chamber 6 becomes a reducing atmosphere. By performing a film forming step described later in this reducing atmosphere, the adhesion between the plastic molded body 91 and the gas barrier thin film 92 can be improved. In this specification, the hydrogen treatment refers to a treatment in which the surface of the plastic molded body 91 is left or exposed in a hydrogen atmosphere. Further, the hydrogen atmosphere includes an atmosphere in which hydrogen in an atomic state such as active hydrogen or hydrogen radical exists in addition to molecular hydrogen. The time for performing the hydrogen treatment step is not particularly limited, but is preferably 1.0 to 200 seconds, more preferably 2.0 to 10 seconds, and particularly preferably 3.0 to 5.0 seconds. It is. If it is less than 1.0 second, there may be a case where the inside of the vacuum chamber 6 cannot be sufficiently reduced. Even if it exceeds 200 seconds, the reduction effect reaches its peak and is uneconomical.

  In this embodiment, it is preferable that the hydrogen treatment step includes at least one of the following steps. Each step will be described.

(Step of bringing hydrogen gas into contact with a heating element that has generated heat)
In the method for manufacturing the gas barrier plastic molded body 90 according to the present embodiment, it is preferable that the hydrogen treatment step includes a step of bringing hydrogen gas into contact with the heating element 18 that has generated heat. In this case, the heating element 18 generates heat before supplying hydrogen gas. The heating element 18 generates heat to a temperature higher than room temperature when energized, for example. The heating temperature of the heating element 18 is preferably 1500 ° C. or higher. More preferably, it is 1700 degreeC or more, More preferably, it is 1900 degreeC or more. As the heating temperature of the heating element 18 increases, the effect of improving the adhesion between the plastic molded body 91 and the gas barrier thin film 92 tends to increase. In particular, by setting the temperature to 1700 ° C. or higher, high-concentration hydrogen radicals are generated, and impurities such as oxides on the surface of the plastic molded body 91 are removed and cleaned by the strong reducing action of the hydrogen radicals. The adhesion between the body 91 and the gas barrier thin film 92 can be further improved. However, the upper limit temperature of the heat generation temperature is preferably lower than the softening temperature of the heat generator. Above the softening temperature, the heating element 18 may be deformed and cannot be controlled. Moreover, there is a concern about damage to the plastic molded body 91 due to heat. Although an upper limit temperature changes with materials of the heat generating body 18, if it is molybdenum, 2300 degreeC is preferable, for example. More preferably, it is 2100 degreeC.

  When the hydrogen gas comes into contact with the heating element 18, it is activated by a decomposition reaction, and atomic state hydrogen such as active hydrogen and hydrogen radicals is generated. The hydrogen in the atomic state reaches the inner wall of the plastic container 11 as the surface of the plastic molded body 91, so that impurities such as oxides on the surface of the plastic molded body 91 are removed and cleaned by a strong reducing action. . More specifically, a hydrogen abstraction reaction or an etching reaction with atomic hydrogen such as activated hydrogen or hydrogen radical occurs. As a result, there is an effect of improving the adhesion between the plastic molded body 91 and the gas barrier thin film 92.

  In the case where the hydrogen treatment step includes a step of bringing hydrogen gas into contact with the heating element 18 that has generated heat, the time for which the hydrogen gas is brought into contact with the heating element 18 is preferably 1.0 to 5.0 seconds. More preferably, it is 2.0 to 4.5 seconds. If it is less than 1.0 second, the effect of improving the adhesion may be insufficient. If it exceeds 5.0 seconds, there is a concern about damage to the plastic molded body 91 due to heat. Further, the plastic molded body 91 may be deformed depending on the material.

(Process to supply hydrogen gas and Al source material gas simultaneously)
In the method for manufacturing the gas barrier plastic molded body 90 according to the present embodiment, it is preferable that the hydrogen treatment step includes a step of supplying the hydrogen gas and the Al source material gas 33 simultaneously. The step of supplying the hydrogen gas and the Al source material gas 33 at the same time can be performed during the entire time or a part of the time of the hydrogen treatment step, but is more preferably performed during the part of the time of the hydrogen treatment step.

  When the hydrogen treatment process is performed for a part of the time, the process includes a process of supplying only hydrogen gas and a process of supplying hydrogen gas and the Al source material gas 33 simultaneously. The order of supplying only the hydrogen gas and the step of supplying the hydrogen gas and the Al source material gas 33 simultaneously is performed, for example, after the step of supplying only the hydrogen gas, The process flow 1 for performing the process of supplying hydrogen gas, the process of supplying the hydrogen gas and the Al source material gas 33 simultaneously, the process flow 2 for performing the process of supplying only hydrogen gas, and the process of repeatedly performing the process flow 1 This is a process flow 4 in which the flow 3 or the process flow 2 is repeated. Among these, the process flow 1 or the process flow 3 is more preferable, and the process flow 1 is particularly preferable. After cleaning the surface of the plastic molded body 91 with the inside of the vacuum chamber 6 in a reduced state, the process of supplying only hydrogen gas is performed earlier than the process of supplying hydrogen gas and the Al source material gas 33 simultaneously. The chemical species 34 derived from the Al source material gas 33 can reach the surface of the plastic molded body 91. As a result, the adhesion between the plastic molded body 91 and the gas barrier thin film 92 can be further enhanced. Between the process of supplying only hydrogen gas and the process of supplying hydrogen gas and Al source material gas 33 at the same time, the hydrogen gas continues to be supplied throughout the entire hydrogen treatment process without stopping the supply of hydrogen gas. It is preferable to further supply the Al source material gas 33 during a part of the time.

  The time for supplying the hydrogen gas and the Al source material gas 33 at the same time is not particularly limited, but is preferably 0 to 70% with respect to the total time of the hydrogen treatment step. More preferably, it is 30 to 60%.

  Since the hydrogen treatment step includes a step of supplying the hydrogen gas and the Al source material gas 33 at the same time, there is an effect of further improving the adhesion between the base material and the gas barrier thin film. The reason is not clear, but is presumed as follows. That is, by supplying the hydrogen gas and the Al source material gas 33 simultaneously, the chemical species 34 derived from the Al source material gas 33 is applied to the surface of the plastic molded body 91 while the surface of the plastic molded body 91 is etched by hydrogen radicals. Reach and deposit. Then, a mixing layer in which the components of the plastic molded body 91 and the components of the chemical species 34 derived from the Al source material gas 33 are mixed is formed on the surface of the plastic molded body 91. In the mixing layer, the component of the plastic molded body 91 and the component of the chemical species 34 derived from the Al source material gas 33 are chemically bonded. When this mixing layer is present at the interface between the plastic molded body 91 and the gas barrier thin film 92, the boundary between the plastic molded body 91 and the gas barrier thin film 92 is unclear, and the adhesion between the plastic molded body 91 and the gas barrier thin film 92 is unclear. Will improve.

  The Al source material gas 33 is supplied by controlling the flow rate by the flow rate regulator 24a. Examples of the Al source material gas 33 include trialkylaluminums such as trimethylaluminum and triethylaluminum, aluminum halides such as aluminum chloride and aluminum bromide, tritertiary butoxyaluminum, triethoxyaluminum, triisopropoxyaluminum, and trisecondary butoxy. Metal aluminum alkoxides such as aluminum, trisacetylacetonate aluminum, trisdipivaloylmethanate aluminum, dimethylaluminum isopropoxide (DMAIP), and trikis (trimethylsiloxy) aluminum. Among these, from the viewpoint of material cost and non-pyrophoric property (safety), metal aluminum alkoxide is more preferable, and DMAIP is particularly preferable.

  When the substance used as the Al source material gas 33 is a liquid, it can be supplied by a bubbling method. The bubbling gas used for the bubbling method is, for example, an inert gas such as nitrogen, argon, or helium, and nitrogen gas is more preferable. That is, when the starting material 41a in the material tank 40a is bubbled while controlling the flow rate with the flow rate regulator 24a using the bubbling gas filled in the cylinder 42a, the starting material 41a is vaporized and taken into the bubbles. Thus, the Al source material gas 33 is supplied in a state of being mixed with the bubbling gas. Further, a method is adopted in which the liquid Al source material gas 33 is vaporized in the cylinder 42a and the Al source material gas 33 filled in the head space in the cylinder 42a is supplied by opening the valve 25a. Also good.

  The carrier gas may be mixed with the Al source material gas 33 or the hydrogen gas before the valve 25d while controlling the flow rate of the carrier gas with the flow rate regulator 24c as necessary. The carrier gas is an inert gas such as argon, helium or nitrogen. Then, the Al source material gas 33 and the hydrogen gas are in a state where the flow rate is controlled by the flow rate regulators 24a and 24b, or in a state where the flow rate is controlled by the carrier gas, in the plastic container 11 decompressed to a predetermined pressure. Then, the gas is blown out from the gas blowing hole 17x of the source gas supply pipe 23 toward the heating element 18.

  Before supplying the hydrogen gas and the Al source material gas 33, the heating element 18 is preferably heated to a temperature higher than room temperature, for example, by energization. The heating temperature of the heating element 18 is preferably 1500 ° C. or higher. More preferably, it is 1700 degreeC or more, More preferably, it is 1900 degreeC or more.

  The partial pressure ratio between the hydrogen gas and the Al source material gas 33 is to change the ratio between the flow rate of the hydrogen gas and the Al source material gas 33 flow rate (the flow rate of the bubbling gas when supplying the Al source material gas 33 by the bubbling method). Can be controlled.

(End of hydrogen treatment)
When a predetermined time has elapsed, supply of hydrogen gas or hydrogen gas and Al source material gas 33 is stopped.

<Film formation process>
The film forming process may be performed continuously without opening to the atmosphere after the hydrogen treatment process, or may be performed intermittently by opening to the atmosphere after the hydrogen treatment, but in terms of obtaining a high hydrogen treatment effect, It is preferable to carry out continuously. In the hydrogen treatment process, when the Al source material gas 33 is supplied, only the hydrogen gas supply may be stopped, the Al source material gas 33 may be continuously supplied, and the film forming process may be continued.

(Heat generation of heating element)
After the hydrogen treatment step, the heating element 18 is adjusted to a temperature suitable for film formation. The heating temperature of the heating element 18 suitable for film formation is preferably 500 ° C. or higher. More preferably, it is 900 degreeC or more, Most preferably, it is 1100 degreeC or more. As described above, the upper limit temperature of the heat generation temperature is preferably lower than the softening temperature of the heat generator 18.

(Source gas supply)
After adjusting the temperature of the heating element 18 to a temperature suitable for film formation, the Al source material gas 33 is supplied at a predetermined flow rate controlled by the flow rate regulator 24a. The method of supplying the Al source material gas 33 is the same as the method described in the step of supplying the hydrogen gas and the Al source material gas 33 at the same time in the hydrogen treatment step, while controlling the flow rate with a carrier gas as necessary. Can be supplied. Further, even when the Al source material gas 33 is liquid, it is as described in the step of supplying the hydrogen gas and the Al source material gas 33 simultaneously.

The Al source material gas 33 is preferably mixed with a gas that does not undergo polymerization but participates in a chemical reaction, such as hydrogen, oxygen, nitrogen, water vapor, nitrous acid gas, carbon dioxide gas, ammonia, or CF ₄ . The quality of the gas barrier thin film can be improved by introducing these into the reaction chamber 12 in which the heating element 18 that has generated heat exists. Among these, it is more preferable to use an oxidizing gas such as oxygen, ozone, hydrogen peroxide, water vapor, nitrous acid gas, and carbon dioxide gas. The flow rate of the oxidizing gas is not particularly limited, but is preferably 0 to 80 sccm. More preferably, it is 5-50 sccm.

(Film formation)
When the Al source material gas 33 comes into contact with the heating element 18, a chemical species 34 containing Al is generated. When the chemical species 34 reaches the inner wall of the plastic container 11, a gas barrier thin film 92 in which one of the constituent elements is Al is deposited. In the deposition of the gas barrier thin film 92, the time for heating the heating element 18 and supplying the Al source material gas 33 (time for blowing the Al source material gas 33 to the heating element 18) is preferably 0.5 to 20 seconds. . More preferably, it is 10 to 15 seconds. The pressure in the vacuum chamber 6 during film formation is preferably reduced until reaching, for example, 1.0 to 100 Pa. More preferably, it is 1.4-50 Pa. When the pressure is reduced to be within this range from the atmospheric pressure, an appropriate residual water vapor pressure derived from the atmosphere, the apparatus and the container can be obtained together with an appropriate vacuum pressure, and the gas barrier thin film 92 can be easily formed.

  In the heating element CVD method, a certain degree of adhesion can be obtained between the plastic molded body 91 and the gas barrier thin film 92 to be formed. However, in this embodiment, the hydrogen treatment process is performed before the film forming process. Necessary adhesion to the container can be ensured.

(Finish film formation)
When the thin film reaches a predetermined thickness, the supply of the Al source material gas 33 is stopped. Then, energization to the heating element 18 is terminated. Next, after evacuating the reaction chamber 12 again, a leak gas (not shown) is introduced to bring the reaction chamber 12 to atmospheric pressure. Thereafter, the upper chamber 15 is opened and the plastic container 11 is taken out. In the method for producing a gas barrier plastic molded body according to this embodiment, the film thickness of the gas barrier thin film 92 is set to 5 to 100 nm in order to achieve both the effect of improving the gas barrier property and the adhesion to the plastic molded body 91. Is preferable. More preferably, it is 10-85 nm, Most preferably, it is 15-50 nm.

  Compared with other chemical vapor deposition methods such as plasma CVD or physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, ion plating, etc., the heating element CVD method is simpler and reduces the cost of the device itself. Can do. Further, in the heating element CVD method, since a gas barrier thin film is formed by deposition of chemical species, a dense film having a higher bulk density can be obtained as compared with the wet method.

  The gas barrier plastic molded body 90 according to the present embodiment is formed by the method for manufacturing a gas barrier plastic molded body according to the present embodiment. The gas barrier plastic molded body 90 according to the present embodiment includes a gas barrier thin film 92 on a plastic molded body 91 as shown in FIG. The gas barrier thin film 92 contains Al and O as constituent elements. As long as the gas barrier thin film 92 contains Al and O as constituent elements, the gas barrier thin film 92 is not limited by the crystal type and the degree of oxidation of the oxide. In addition to Al and O, the gas barrier thin film is a metal element derived from a heating element such as Mo (molybdenum), other such as C (carbon), H (hydrogen), N (nitrogen), Si (silicon), and Ti (titanium). These elements may be included. However, the content of elements other than Al and O measured by XPS analysis of the gas barrier thin film 92 is 30 at. % (Atomic%) or less is preferable. More preferably, 20 at. % Or less.

This gas barrier plastic molded body 90 can have a barrier property improvement rate (Barrier Improvement Factor, hereinafter referred to as “BIF”) of 10 or more, which is obtained by Equation 1. As a specific example, the oxygen permeability when the container capacity of the gas barrier plastic container is 500 ml can be 0.0030 cc / container / day or less.
(Equation 1) BIF = [Oxygen permeability of plastic molding without thin film] / [Oxygen permeability of gas barrier plastic molding]

  In the gas barrier plastic molded body 90 according to the present embodiment, the adhesion between the plastic molded body 91 and the gas barrier thin film 92 is improved by performing the hydrogen treatment step, and has physicochemical stability in an aqueous solution. Therefore, it is suitable as a packaging application for food or beverage.

  Next, the present invention will be described in more detail with reference to examples, but the present invention is not construed as being limited to the examples.

Example 1
As a plastic molded body, on the inner surface of a 500 ml PET bottle (height 205 mm, body outer diameter 66 mm, mouth outer diameter 27.43 mm, mouth inner diameter 21.74 mm, wall thickness 300 μm and resin amount 31 g), FIG. A gas barrier thin film was formed using the film forming apparatus shown. As the heating element 18, two molybdenum wires having a diameter of 0.5 mm and a length of 43 cm were used. The pipes from the flow rate regulators 24a to 24c to the gas supply port 16 were all made of stainless steel 1/4 inch pipes. The PET bottle was accommodated in the vacuum chamber 8 and decompressed until it reached 1.4 Pa. In the hydrogen treatment step, hydrogen gas was supplied from the flow rate regulator 24b at a flow rate of 30 sccm. The hydrogen treatment time was 200 seconds. Thereafter, the film forming step was performed as follows without opening to the atmosphere. A direct current of 5.5 V was applied to the heating element 18 to generate heat at 1100 ° C. DMAIP was used as the Al source material gas 33, and a thin film was deposited on the inner surface of the PET bottle. The pressure during film formation was 1.4 Pa. The time for supplying the Al source material gas in the film forming process was 13 seconds.

(Example 2)
In Example 1, the heating element 18 was heated to 1900 ° C. during the hydrogen treatment step, and the hydrogen treatment time was set to 5 seconds in the hydrogen treatment step. A thin film was deposited.

(Example 3)
In Example 1, in the hydrogen treatment process, when hydrogen gas is supplied for 198 seconds in 200 seconds, DMAIP is further supplied as an Al source material gas, and hydrogen gas and Al source material gas are supplied simultaneously for 2 seconds. In the film forming step, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 1 except that the time for supplying the Al source material gas was 11 seconds.

Example 4
In Example 1, during the hydrogen treatment step, the heating element 18 is heated to 1700 ° C., and in the hydrogen treatment step, the supply amount of hydrogen gas is 10 sccm, the hydrogen treatment time is 5 seconds, of which 5 hours When the gas is supplied for 2 seconds, DMAIP is further supplied as the Al source material gas, hydrogen gas and the Al source material gas are supplied simultaneously for 3 seconds, and the time for supplying the Al source material gas in the film-forming process is set. A thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 1 except that the time was 10 seconds.

(Example 5)
In Example 1, the heating element 18 is heated to 1900 ° C. during the hydrogen treatment step, and the hydrogen treatment time is set to 5 seconds in the hydrogen treatment step. Example except that DMAIP is supplied as the Al source material gas, hydrogen gas and Al source material gas are supplied simultaneously for 2 seconds, and the Al source material gas is supplied for 11 seconds in the film forming step. In the same manner as in No. 1, a thin film was deposited on the inner surface of the PET bottle.

(Example 6)
In Example 1, the heating element 18 is heated to 1900 ° C. during the hydrogen treatment step, and the hydrogen treatment time is set to 5 seconds in the hydrogen treatment step. Example except that DMAIP is supplied as the Al source material gas, hydrogen gas and Al source material gas are supplied simultaneously for 2 seconds, and the time for supplying the Al source material gas in the film forming step is 10 seconds. In the same manner as in No. 1, a thin film was deposited on the inner surface of the PET bottle.

(Example 7)
In Example 6, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 6 except that the supply amount of hydrogen gas was 50 sccm in the hydrogen treatment step.

(Example 8)
In Example 6, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 6 except that in the hydrogen treatment step, the supply amount of hydrogen gas was 100 sccm.

(Comparative Example 1)
In Example 1, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 1 except that the hydrogen treatment step was not performed.

(Comparative Example 2)
In Example 1, during the hydrogen treatment process, the heating element 18 is heated to 1900 ° C., and in the hydrogen treatment process, hydrogen gas and DMAIP as the Al source material gas are simultaneously supplied for 3 seconds, and the film forming process is not performed. A thin film was deposited on the inner surface of the PET bottle in the same manner as in Example 1 except that.

(Comparative Example 3)
In Comparative Example 2, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 2 except that the supply amount of hydrogen gas was 100 sccm in the hydrogen treatment step.

(Comparative Example 4)
In Comparative Example 2, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 2, except that the time for simultaneously supplying hydrogen gas and DMAIP as the Al source material gas in the hydrogen treatment step was 2 seconds. I let you.

(Comparative Example 5)
In Example 1, the hydrogen treatment step was not performed, and tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film formation step. A thin film was deposited on the inner surface of the PET bottle.

(Comparative Example 6)
In Comparative Example 5, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 5 except that the time for supplying the Ti source material gas in the film forming step was 20 seconds.

(Comparative Example 7)
In Example 1, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 1 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 8)
In Example 2, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 2 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 9)
In Example 3, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 3 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 10)
In Example 5, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 5 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 11)
In Example 6, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 6 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 12)
In Comparative Example 11, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 11, except that the time for supplying the Ti source material gas in the film forming step was 12 seconds.

(Comparative Example 13)
In Comparative Example 11, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 11, except that the time for supplying the Ti source material gas was 14 seconds in the film forming step.

(Comparative Example 14)
In Comparative Example 11, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 11, except that the time for supplying the Ti source material gas in the film forming step was 17 seconds.

(Comparative Example 15)
In Example 7, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 7 except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 16)
In Example 2, the supply amount of hydrogen gas was 50 sccm in the hydrogen treatment step, and tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film formation step. In the same manner as in Example 2, a thin film was deposited on the inner surface of the PET bottle.

(Comparative Example 17)
In Example 8, a thin film was formed on the inner surface of the PET bottle in the same manner as in Example 8, except that tetrakisdimethylamido titanium (TDMAT) was used as the Ti source material gas instead of the Al source material gas in the film forming step. Was deposited.

(Comparative Example 18)
In Comparative Example 17, a thin film was deposited on the inner surface of the PET bottle in the same manner as in Comparative Example 17, except that the supply amount of hydrogen gas was 150 sccm in the hydrogen treatment step.

  The plastic moldings of the obtained Examples and Comparative Examples were evaluated by the following methods. The evaluation results are shown in Table 1.

(Gas barrier property-BIF)
For the PET bottles of Example 6, Comparative Example 1, Comparative Example 5, and Comparative Example 11, the gas barrier properties were evaluated by BIF. In BIF, in Equation 1, the value of oxygen permeability of the PET bottle obtained in the example or the comparative example is defined as “oxygen permeability of the gas barrier plastic molding”, and the oxygen permeability of the PET bottle in which the thin film is not formed is defined as “thin film”. It was calculated as “oxygen permeability of an unformed plastic molding”. The oxygen permeability was measured at 23 ° C. and 90% RH using an oxygen permeability measuring device (model: Oxtran 2/20, manufactured by Modern Control), conditioned for 24 hours from the start of measurement, and then started measurement. The value after 72 hours had passed. The oxygen permeability of the PET bottle with no thin film formed was 0.0350 cc / container / day.

(Film thickness)
The film thickness is a value measured using a stylus type step meter (model: α-step IQ, manufactured by KLA-Tencor).

(Adhesion-water resistance)
500 ml of distilled water was filled in the PET bottles of Examples or Comparative Examples and stored at room temperature (25 ° C.). The presence or absence of peeling of the film was determined by visually observing the PET bottle and the presence or absence of hydrophilicity on the inner surface. That is, when distilled water is wet on the entire inner surface and is hydrophilic, it is determined that there is no peeling, and when there is a water-repellent part where distilled water is not wet on the inner surface, it is determined that there is peeling. . Table 1 shows the number of days until the determination of peeling occurs after filling. 7 days or more was regarded as a practical level, and less than 7 days was regarded as a practical inappropriate level.

  The PET bottles of the examples all had high adhesion. Moreover, when gas barrier property was evaluated about Example 6, BIF was 10, and the high gas barrier property equivalent to the comparative example 1 which did not perform hydrogen treatment was shown. The examples other than Example 6 also had high gas barrier properties. It was confirmed that the hydrogen treatment did not adversely affect the gas barrier properties.

  Comparing Example 1 and Example 2, in Example 2, since the hydrogen treatment step includes a step of bringing hydrogen gas into contact with a heating element that generates heat, the hydrogen treatment step is closer to that in Example 1 in a shorter hydrogen treatment time. A thin film having excellent properties could be formed. Comparing Example 2 and Example 5, Example 5 includes a step of supplying hydrogen gas and Al source material gas at the same time, so that a thin film having better adhesion than Example 2 can be formed. It was. When Example 2 is compared with Example 6, Example 6 is shorter in time for supplying the Al source material gas in the film forming process than Example 2, but Example 6 is a hydrogen gas and Al source material. Since the process of supplying gas at the same time was included, the film thickness of Example 6 was greater than that of Example 2 in a shorter time. Therefore, it has been confirmed that the process time can be shortened by including the process of simultaneously supplying the hydrogen gas and the Al source material gas. This leads to cost reduction. Moreover, it is beneficial in that the heat load on the plastic molded body can be reduced.

  Since the comparative example 1 did not perform the hydrogen treatment step, the adhesion was poor, and the adhesion was peeled off within one day in the adhesion evaluation. In Comparative Examples 2 to 4, hydrogen gas and Al source material gas were supplied at the same time, and only the Al source material gas was not subjected to the film forming process. Peeled within. Comparative Examples 5 to 18 are examples using TDMAT containing Ti as a raw material gas. Since the comparative example 5 and the comparative example 6 did not perform the hydrogen treatment process, the adhesiveness was poor, and the adhesiveness evaluation peeled off within one day. In Comparative Examples 7 to 18, attempts were made to improve the adhesion by changing the conditions of the hydrogen treatment process, but there were examples in which the adhesion was slightly improved, but all of them were peeled off in less than 7 days. As a result, the effect as remarkable as that of the AlOx film could not be confirmed.

  In the gas barrier plastic molded body according to the present invention, the adhesion between the plastic molded body and the gas barrier thin film is improved by performing the hydrogen treatment step, and has physicochemical stability in an aqueous solution. Therefore, it is suitable as a packaging application for food or beverage.

6 Vacuum chamber 8 Vacuum valve 11 Plastic container 12 Reaction chamber 13 Lower chamber 14 O-ring 15 Upper chamber 16 Gas supply port 17 Material gas flow path 17x Gas blowing hole 18 Heating element 19 Wiring 20 Heater power supply 21 Port 22 Exhaust pipe 23 Material Gas supply pipes 24a, 24b, 24c Flow rate regulators 25a, 25b, 25c, 25d Valves 26a, 26b Connection portion 27 Cooling water flow path 28 Inner surface 29 Cooling means 33 Al source material gas 34 Chemical species 35 Insulating ceramic member 40a Material tank 41a Start Raw material 42a, 42b, 42c Cylinder 90 Gas barrier plastic molded body 91 Plastic molded body 92 Gas barrier thin film 100 Film forming apparatus

Claims (5)

In the method for producing a gas barrier plastic molded body, in which a gas barrier thin film containing aluminum (Al) and oxygen (O) as constituent elements is formed on the surface of the plastic molded body by a heating element CVD method,
A hydrogen treatment step of reducing the surface of the plastic molded body by supplying hydrogen gas to the inside of the vacuum chamber containing the plastic molded body,
An Al source material gas is supplied into a vacuum chamber containing the plastic molded body, and the Al source material gas is brought into contact with a heat generating element that generates heat, and the Al source material gas is decomposed to generate chemical species. And a film forming step of forming the gas barrier thin film by causing the chemical species to reach the surface of the plastic molded body.   The method for producing a gas barrier plastic molded body according to claim 1, wherein the hydrogen treatment step includes a step of bringing hydrogen gas into contact with a heating element that generates heat.   The method for producing a gas barrier plastic molded body according to claim 1, wherein the hydrogen treatment step includes a step of simultaneously supplying hydrogen gas and the Al source material gas.   The method for producing a gas barrier plastic molded article according to any one of claims 1 to 3, wherein the plastic molded article is a film, a sheet, or a container.   A gas barrier plastic molded article formed by the method for producing a gas barrier plastic molded article according to any one of claims 1 to 4.

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