JP2004196351A - Apparatus for forming carbon film on inner surface of plastic container and method for manufacturing plastic container covered with inner surface carbon film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for forming a carbon film on the inner surface of a plastic container capable of preventing a deformation of the container when the carbon film is coated on the inner surface of the plastic container. <P>SOLUTION: This carbon film forming apparatus comprises an external electrode having such a size as one enclosing an outer circumference of a plastic container to be processed when the container is inserted into the apparatus; a gas discharging pipe fixed through an insulation member to the end surface of the external electrode at a side where the opening of the container is positioned; an internal electrode inserted at the gas discharging pipe into the plastic container in the external electrode, connected to a ground side and having a gas blowing-out hole for discharging medium gas punched therein; either a gas discharging hole or a gas discharging groove punched along the inner surface where the plastic container of the external electrode is inserted at the end surface of the gas discharging pipe side of the external electrode; a gas discharging means fixed to the gas discharging pipe; a gas supplying means for supplying medium gas to the internal electrode; and a high frequency power supply connected to the external electrode. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for forming a carbon film on the inner surface of a plastic container and a method for manufacturing a plastic container coated with an inner carbon film.
[0002]
[Prior art]
Plastic containers, for example, PET bottles, are coated with a carbon film such as DLC (Diamond Like Carbon) on the inner surface to prevent permeation of oxygen from outside and permeation of carbon dioxide from inside (for example, carbonated drinking water). Have been tried.
[0003]
As a method of coating a carbon film on the inner surface of such a plastic container, Japanese Patent Application Laid-Open No. 8-53116 and Japanese Patent No. 2788412 (Japanese Patent Application Laid-Open No. 8-53117) disclose a method using high-frequency plasma. Japanese Patent Application Laid-Open No. 9-272567 discloses a method of coating a film with a carbon film using high-frequency plasma as an applied method. Japanese Patent No. 3072269 (Japanese Patent Application Laid-Open No. 10-226888) discloses a method of coating a carbon film corresponding to a specially-shaped container, and Japanese Patent No. 3115252 (Japanese Patent Application Laid-Open No. 10-258825) discloses a method of mass production. A method for simultaneously coating a container is disclosed. References that disclose techniques for coating a plastic container with a carbon film include "K. Takemoto, et al, Proceedings of ADC / FCT '99, p285" and "E. Shimamura et al, 10th years IAPRI World Conference 1997. , p251 ".
[0004]
Japanese Patent No. 2788412 (JP-A-8-53116), which is a basic invention of coating a plastic container with a carbon film using high-frequency plasma CVD, will be described with reference to FIG. FIG. 6 is a sectional view of an apparatus for coating a plastic container with a carbon film using high-frequency plasma CVD described in this publication.
[0005]
The external electrode 101 is provided on a mount 102 via a sealing plate 103 made of, for example, polytetrafluoroethylene. The external electrode 101 has an inner shape substantially along the outer shape of a plastic container to be housed, for example, a bottle B. The external electrode 101 also preferably has an inner shape along the screw shape for the bottle cap at the base. The external electrode 101 includes a cylindrical main body 101a and a cap portion 101b attached to an upper end of the main body 101a, and also serves as a vacuum container. The gas exhaust pipe 104 communicates with the lower part of the external electrode 101 through the gantry 102 and the seal plate 103.
[0006]
The internal electrode 105 is inserted into a bottle B housed in the external electrode 101. The internal electrode 105 has a hollow structure, and has a plurality of gas blowing holes 106 formed on the surface. A gas supply pipe 107 for supplying a medium gas for CVD penetrates the gantry 102 and the seal plate 103 and communicates with the lower end of the internal electrode 105. The medium gas for CVD is supplied into the internal electrode 105 through the supply pipe 107, and is supplied into the bottle B from the gas outlet 106.
[0007]
The RF input terminal 108 is connected to the lower part of the external electrode 101 through the gantry 102 and the seal plate 103. This RF input terminal 108 is electrically insulated from the gantry 102. The lower end of the RF input terminal 108 is connected to a high-frequency power supply 110 through a matching unit 109. High frequency power for plasma generation is applied to the external electrode 101 from a high frequency power supply 110 through the matching unit 109 and the RF input terminal 108.
[0008]
A method of coating the inner surface of a PET bottle with a carbon film using the apparatus having such a configuration will be described.
[0009]
First, a PET bottle B is inserted into the main body 101a of the external electrode 101, and a cap 101b is attached to the main body 101a, whereby the bottle B is hermetically stored in the external electrode 101. Gas in the external electrode 101 is exhausted through a gas exhaust pipe 104. At this time, gas in the space inside and outside the bottle B housed in the external electrode 101 is exhausted through the opening of the seal plate 103. Specified vacuum degree (representative value: 10 ^-2 -10 ^-Five After the pressure reaches Torr, a medium gas is supplied to the internal electrode 105 through the gas supply pipe 107 at a flow rate of, for example, 10 to 50 mL / min, and is further blown into the bottle B through the gas blowing hole 106 of the internal electrode 105. As the medium gas, for example, aliphatic hydrocarbons such as benzene, toluene, xylene, and cyclohexane, aromatic hydrocarbons, oxygen-containing hydrocarbons, and nitrogen-containing hydrocarbons are used. The pressure in the bottle B is, for example, 2 × 10 ^-1 ~ 1 × 10 ^-2 Set to Torr. After that, high-frequency power of 50 to 1000 W is applied from the high-frequency power supply 110 to the external electrode 101 through the matching unit 109 and the RF input terminal 108.
[0010]
By applying such high-frequency power to the external electrode 101, plasma is generated between the external electrode 101 and the internal electrode 105. At this time, since the plastic bottle B is stored in the external electrode 101 with almost no gap, plasma is generated in the plastic bottle B. The medium gas is dissociated or further ionized by the plasma to generate a film-forming species for forming a carbon film, and the film-forming species is deposited on the inner surface of the bottle B to form a carbon film. After the carbon film is formed to a predetermined thickness, the application of the high-frequency power is stopped, the supply of the medium gas is stopped, the residual gas is exhausted, nitrogen, a rare gas, air, or the like is supplied into the external electrode 101. Return to atmospheric pressure. Thereafter, the bottle B is removed from the external electrode 101. In this method, it takes 2 to 3 seconds to form a carbon film having a thickness of 30 nm.
[0011]
[Problems to be solved by the invention]
However, in the invention of Patent No. 2788412, when the gas in the space inside and outside the bottle B housed in the external electrode 101 is exhausted through the opening of the seal plate 103 in the exhaustion of the gas in the bottle B, the bottle B is deformed. Another problem is that it is difficult to coat the inner surface of the other bottle B with a carbon film having a uniform thickness.
[0012]
An object of the present invention is to provide an apparatus for forming a carbon film on the inner surface of a plastic container, which can prevent deformation of the plastic container when the inner surface of the plastic container is coated with a carbon film.
[0013]
An object of the present invention is to provide a method for manufacturing a plastic container in which a carbon film having a uniform thickness is coated on the inner surface.
[0014]
The present invention provides an apparatus for forming a carbon film on an inner surface of a plastic container, which can prevent deformation of the container when coating the inner surface of the plastic container with a carbon film and can perform coating at a high speed. Aim.
[0015]
An object of the present invention is to provide a method for manufacturing a plastic container in which a carbon film having a uniform thickness is coated on the inner surface at a high speed.
[0016]
[Means for Solving the Problems]
The apparatus for forming a carbon film on the inner surface of a plastic container and the method for producing a plastic container coated with an inner carbon film according to the present invention are characterized by having the following configuration.
[0017]
1) an external electrode having a size that surrounds the outer periphery of a plastic container that is an object to be processed when the container is inserted;
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the external electrode on the exhaust pipe side to an inner surface of the external electrode into which the plastic container is inserted;
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the internal electrode,
A high-frequency power supply connected to the external electrode,
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising:
[0018]
2) In manufacturing an inner carbon film-coated plastic container using the carbon film forming apparatus of the above 1),
(A) inserting a plastic container as an object to be processed into an external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) exhausting gas in the container through the exhaust pipe by exhaust pipe means, and exhausting gas between the outer surface of the container and the external electrode from an exhaust hole or exhaust groove formed in the external electrode; After exhausting through the pipe, a medium gas is supplied to the internal electrode by a gas supply means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to pass a predetermined gas through the exhaust pipe including the plastic container. Setting the pressure;
(D) supplying a high-frequency power from a high-frequency power source to the external electrode to generate plasma around the internal electrode located in the plastic container, and dissociate the medium gas by the plasma to form a carbon film on the inner surface of the plastic container; Coating process and
A method for producing a plastic container coated with an inner carbon film, comprising:
[0019]
3) an external electrode having a size that surrounds a plastic container, which is an object to be processed, when the container is inserted;
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the external electrode on the exhaust pipe side to an inner surface of the external electrode into which the plastic container is inserted;
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the gas supply pipe,
A high-frequency power supply connected to the gas supply pipe,
A bias power supply connected to the external electrode;
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising:
[0020]
4) In manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus of the above 3),
(A) inserting a plastic container as an object to be processed into an external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) exhausting gas in the container through the exhaust pipe by exhaust pipe means, and exhausting gas between the outer surface of the container and the external electrode from an exhaust hole or exhaust groove formed in the external electrode; After exhausting through a pipe, a medium gas is supplied to the internal electrode from the gas supply pipe means, and a medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to evacuate the inside of the exhaust pipe including the plastic container. Setting a gas pressure of
(D) applying high-frequency power from a bias power supply to the external electrode, supplying high-frequency power from the high-frequency power supply to the internal electrode, and generating plasma in the plastic container; Dissociating and coating the inner surface of the plastic container with a carbon film;
A method for producing a plastic container coated with an inner carbon film, comprising:
[0021]
5) an external electrode having a size surrounding the plastic container, which is the object to be processed, when the container is inserted;
A spacer made of a dielectric material interposed between at least the mouth and shoulders of the container and the external electrode when the plastic container as the object to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the spacer on the exhaust pipe side to an inner surface of the spacer into which the plastic container is inserted,
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the internal electrode,
A high-frequency power supply connected to the external electrode,
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising:
[0022]
6) In manufacturing an inner carbon film-coated plastic container using the carbon film forming apparatus of the above 5),
(A) A plastic container to be processed is placed in an external electrode and a spacer made of a dielectric material, at least the outer periphery of the mouth and shoulder of the container is surrounded by the spacer, and the other parts of the container are Inserting the outer periphery so as to be surrounded by the external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) The gas in the container is exhausted through the exhaust pipe by an exhaust pipe means, and gas between the outer surface of the container and the external electrode and the spacer is discharged from an exhaust hole or an exhaust groove formed in the spacer. After exhausting through the exhaust pipe, a medium gas is supplied to the internal electrode by gas supply means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode so that the inside of the exhaust pipe including the inside of the plastic container is predetermined. Setting a gas pressure of
(D) supplying a high-frequency power from a high-frequency power source to the external electrode to generate plasma around the internal electrode located in the plastic container, and dissociate the medium gas by the plasma to form a carbon film on the inner surface of the plastic container; Coating process and
A method for producing a plastic container coated with an inner carbon film, comprising:
[0023]
7) an external electrode having a size surrounding the plastic container, which is the object to be processed, when the container is inserted;
A spacer made of a dielectric material interposed between the external electrode and at least the mouth and shoulders of the container when the plastic container that is to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An exhaust hole or an exhaust groove pierced from an end surface of the spacer on the exhaust pipe side to an inner surface of the spacer into which the plastic container is inserted,
An internal electrode which is inserted into the plastic container in the external electrode and has a gas blowing hole for blowing out a medium gas,
A gas supply pipe having one end connected to the internal electrode and the other end also serving as a power supply terminal extended to the exhaust pipe side;
An earth shield tube which is arranged at least on the outer periphery of the gas supply pipe portion located in the exhaust pipe near the mouth of the container and near the mouth of the container, and is grounded.
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the gas supply pipe,
A high-frequency power supply connected to the gas supply pipe,
A bias power supply connected to the external electrode;
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising:
[0024]
8) In manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus of the above 7),
(A) A plastic container to be processed is placed in an external electrode and a spacer made of a dielectric material, at least the outer periphery of the mouth and shoulder of the container is surrounded by the spacer, and the other parts of the container are Inserting the outer periphery so as to be surrounded by the external electrode;
(B) A gas supply pipe having a grounded earth shield disposed on the outer periphery thereof is connected, and an internal electrode provided with a gas blowing hole is provided with an insulating member on an end face of the external electrode on the side where the mouth of the container is located. Inserting the inside of the plastic container from the exhaust pipe attached via,
(C) The gas in the container is exhausted through the exhaust pipe by an exhaust pipe means, and gas between the outer surface of the container and the external electrode and the spacer is discharged from an exhaust hole or an exhaust groove formed in the spacer. After exhausting through the exhaust pipe, a medium gas is supplied to the internal electrode from the gas supply pipe means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to exhaust gas including the inside of the plastic container. Setting to a predetermined gas pressure,
(D) applying high frequency power from a bias power source to the external electrode and supplying high frequency power from the high frequency power source to the internal electrode through the gas supply pipe to generate plasma in the plastic container; Coating the inner surface of the plastic container with a carbon film by dissociating the medium gas according to the method described above.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
[0026]
(First embodiment)
FIG. 1 is a sectional view showing an apparatus for forming a carbon film on the inner surface of a plastic container according to the first embodiment, and FIG. 2 is a perspective view showing an external electrode of FIG.
[0027]
A cylindrical support member 2 having flanges 1 a and 1 b at upper and lower ends is mounted on an annular base 3. A cylindrical external electrode body 4 made of metal is arranged inside the support member 2. A disk-shaped metal external electrode bottom member 5 is detachably attached to the bottom of the external electrode 4. The external electrode body 4 and the external electrode bottom member 5 constitute a bottomed cylindrical external electrode 6 having a space large enough to accommodate a plastic container (for example, a PET bottle) B on which a carbon film is formed. The disk-shaped insulator 7 is arranged between the base 3 and the external electrode bottom member 5.
[0028]
The external electrode bottom member 5, the disc-shaped insulator 7, and the base 3 are moved up and down integrally with the external electrode body 4 by a pusher (not shown) to open and close the bottom of the external electrode body 4. I do.
[0029]
The annular insulating member 8 is mounted on the upper surface of the external electrode 6 such that the upper surface of the annular insulating member 8 is flush with the upper flange 1 a of the tubular support member 2. A gas exhaust pipe 10 having upper and lower flanges 9 a and 9 b is mounted on the upper flange 1 a of the support member 2 and the upper surface of the annular insulating member 8. This exhaust pipe 10 is grounded. The gas exhaust pipe 10 is fixed to the support member 2 by screwing a screw (not shown) from the lower flange 9b of the exhaust pipe 10 to the upper flange 1a of the support member 2. Further, by screwing a screw (not shown) from the lower flange 9b of the exhaust pipe 10 to the main body 4 of the external electrode 6 through the annular insulating portion 8, the exhaust pipe 10 is connected to the annular insulating member 8 and the external electrode. 6 and the annular insulating member 8 is also fixed to the external electrode 6. The fixing of the exhaust pipe 10 to the annular insulating member 8 and the external electrode 6 has a mounting structure in which the exhaust pipe 10 and the external electrode 6 are not electrically connected by screws. The branch gas exhaust pipe 11 is connected to a side wall of the gas exhaust pipe 10, and exhaust equipment such as a vacuum pump (not shown) is attached to the other end. The lid 12 is attached to the upper flange 9a of the exhaust pipe 10.
[0030]
As shown in FIGS. 1 and 2, the plastic container of the main body 4 of the external electrode 6 is inserted into the plurality of, for example, four exhaust holes 13 from the end face of the main body 4 of the external electrode 6 on the exhaust pipe 10 side. It is drilled over the inner surface. In particular, as shown in FIGS. 1 and 2, one end (upper end) of the four exhaust holes 13 is opened at the end surface of the main body 4 of the external electrode 6 on the exhaust pipe 10 side, and the other end (lower end) is inserted. It is preferable that an opening is provided at an inner surface portion (for example, a portion corresponding to a shoulder position of the PET bottle B) of the external electrode 6 below a flange position P of a mouth portion of the PET bottle B to be formed. If the cross-sectional area of these exhaust holes 13 is small, smooth exhaust of gas between the external electrode 6 and the PET bottle B is hindered, while if the cross-sectional area of the exhaust holes 13 is large, plasma is generated in the exhaust holes 13. Is easily generated. Therefore, it is preferable that the cross-sectional area of each of the exhaust holes 13 satisfies the following relationship.
[0031]
(S _p / V _p ) ≦ (S _e / V _g )
Where S _p Is the cross-sectional area of the mouth of the plastic bottle, V _p Is the volume of the plastic bottle, S _e Is the cross-sectional area of the exhaust hole, V _g Is the volume of the gap between the external electrode and the plastic bottle.
[0032]
For example, a high-frequency power supply 14 that outputs high-frequency power having a frequency of 13.56 MHz is connected to the main body 4 of the external electrode 6 through a cable 15 and a power supply terminal 16. The matching device 17 is interposed in the cable 15 between the high-frequency power supply 14 and the power supply terminal 16.
[0033]
The gas supply pipe 18 penetrates the lid 12 and is inserted through the gas exhaust pipe 10 into the body 4 of the external electrode 6 at a position corresponding to the mouth of the plastic bottle B. The substantially cylindrical internal electrode 19 is disposed in the plastic bottle B inserted into the external electrode 6 over substantially the entire length of the plastic bottle B in the longitudinal direction, and its upper end is located at the lower end of the gas supply pipe 18. It is attached detachably. The internal electrode 19 has a gas channel 20 cut out in the center axis, and a cap 22 having a gas blowing hole 21 for blowing out a medium gas at the bottom portion, which is detachably attached.
[0034]
In addition, the gas outlet may be opened in the lower side wall of the internal electrode 19 so as to communicate with the gas flow path 20. In this case, it is preferable that the gas blowing hole be opened in a side surface region within a range from the bottom of the internal electrode 19 to 25% of the length inserted into the plastic bottle B.
[0035]
The diameter of the internal electrode 19 is equal to or less than the diameter of the base of the bottle B, and the length is a length that can be inserted over substantially the entire length of the plastic bottle B in the longitudinal direction. As a guide of the length, the ratio to the total length of the PET bottle B is set to be about {1-D / (2L)}. Here, D represents the inner diameter of the PET bottle, L represents the total length of the PET bottle, and L> (D / 2).
[0036]
The internal electrode 19 is made of a heat-resistant metal material such as tungsten or stainless steel, but may be made of aluminum. If the surface of the internal electrode 19 is smooth, the carbon film deposited on the surface of the internal electrode 19 may be easily peeled off. For this reason, it is preferable that the surface of the internal electrode 19 is subjected to sandblasting in advance to increase the surface roughness so that the carbon film deposited on the surface is hardly peeled off.
[0037]
Next, a method of manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus shown in FIG. 1 will be described.
[0038]
The external electrode bottom member 5, the disk-shaped insulator 7, and the base 3 are removed by a pusher (not shown) to open the bottom of the external electrode body 4. Subsequently, after the plastic container, for example, the plastic bottle B is inserted from the bottom side of the opened external electrode body 4 from the mouth side of the bottle B, the external electrode bottom member 5 is inserted into the bottom side of the external electrode body 4 by a pusher (not shown). By attaching the disc-shaped insulator 7 and the base 3 in this order, the plastic bottle B is placed in the internal space of the external electrode body 4 and the external electrode 6 which is the shell of the external electrode bottom member 5 as shown in FIG. Is stored. At this time, the PET bottle B is communicated with the exhaust pipe 10 through its mouth.
[0039]
Next, gas inside and outside the exhaust pipe 19 and the PET bottle B is exhausted through a branch exhaust pipe 20 and an exhaust pipe 19 by an exhaust means (not shown). At this time, a plurality of, for example, four exhaust holes 13 are connected to the PET bottle B of the main body 4 in the external electrode 6 from the end face of the main body 4 of the external electrode 6 on the exhaust pipe 10 side as shown in FIGS. Is formed at an equal angle (90 °) with respect to the center of the main body 4 over the inner surface into which is inserted, so that not only the gas in the PET bottle B but also the outer surface of the PET bottle B and the external electrode 6 is exhausted through the plurality of exhaust holes 13. As a result, the pressure inside and outside the plastic bottle B is balanced, and deformation of the plastic bottle B due to the pressure difference between the inside and outside can be prevented.
[0040]
In particular, as shown in FIGS. 1 and 2, one end (upper end) of the four exhaust holes 13 is opened at the end surface of the main body 4 of the external electrode 6 on the exhaust pipe 10 side, and the other end (lower end) is inserted. Opening at the inner surface portion of the external electrode 6 (for example, a portion corresponding to the shoulder position of the PET bottle B) below the flange position P of the mouth of the PET bottle B, and the cross-sectional area of each of the exhaust holes 13 S _p / V _p ) ≦ (S _e / V _g By setting so as to satisfy the relationship of (3), the gas remaining between the outer surface of the PET bottle B and the external electrode 6 can also be effectively exhausted through the plurality of exhaust holes 13. And the deformation caused by the pressure difference between the inside and outside of the PET bottle B can be more reliably prevented, and unnecessary plasma can be prevented from being generated in the exhaust hole 13.
[0041]
Next, the medium gas is supplied to the gas flow path 20 of the internal electrode 19 through the gas supply pipe 18, and is blown into the PET bottle B from the gas blowout hole 21 of the cap 22 attached to the bottom of the internal electrode 19. This medium gas further flows toward the mouth of the plastic bottle B. Subsequently, the gas supply amount and the gas exhaust amount are balanced, and the inside of the PET bottle B is set to a predetermined gas pressure.
[0042]
Next, high-frequency power having a frequency of, for example, 13.56 MHz is supplied from the high-frequency power supply 14 to the main body 4 of the external electrode 6 through the cable 15, the matching unit 17, and the power supply terminal 16. At this time, plasma is generated around the internal electrode 19. Due to the generation of the plasma, the medium gas is dissociated by the plasma, and the inner surface of the PET bottle B in the external electrode 6 is coated with a uniform carbon film having a uniform thickness.
[0043]
After the thickness of the carbon film reached a predetermined thickness, the supply of the high-frequency power from the high-frequency power supply 14 was stopped, the supply of the medium gas was stopped, the residual gas was exhausted, and the exhaust of the gas was stopped. Thereafter, nitrogen, a rare gas, air, or the like is supplied into the plastic bottle B through the gas supply pipe 18, through the gas flow path 20 of the internal electrode 19, and the gas blowout hole 21 of the cap 22. And take out the PET bottle coated with the inner carbon film. After that, the PET bottle B is exchanged according to the above-described order, and the process proceeds to the coating operation of the next PET bottle.
[0044]
The medium gas is based on hydrocarbons, for example, alkanes such as methane, ethane, propane, butane, pentane and hexane; alkenes such as ethylene, propylene, butene, pentene and butadiene; alkynes such as acetylene; Aromatic hydrocarbons such as toluene, xylene, indene, naphthalene and phenanthrene; cycloparaffins such as cyclopropane and cyclohexane; cycloolefins such as cyclopentene and cyclohexene; oxygen-containing hydrocarbons such as methyl alcohol and ethyl alcohol; methyl Nitrogen-containing hydrocarbons such as amine, ethylamine, and aniline can be used, and carbon monoxide, carbon dioxide, and the like can also be used.
[0045]
The high-frequency power generally has a frequency of 13.56 MHz and a power of 100 to 1000 W, but is not limited thereto.
[0046]
As described above, according to the first embodiment, when the gas inside and outside the plastic bottle B is exhausted through the exhaust pipe 10, not only the gas inside the plastic bottle B but also stays between the external surface of the plastic bottle B and the external electrode 6. The exhaust gas is also exhausted through the plurality of exhaust holes 13 formed in the external electrode 6 shown in FIGS. 1 and 2 so that the pressure inside and outside the PET bottle B is balanced, and the pressure inside and outside the PET bottle B is reduced. Deformation caused by the pressure difference can be prevented. As a result, a carbon film having a uniform thickness can be coated on the inner surface of the PET bottle B by the subsequent supply of the medium to the PET bottle B and generation of plasma. Therefore, it is possible to mass-produce an inner carbon film-coated PET bottle having an excellent barrier property and preventing permeation of oxygen from the outside and permeation of carbon dioxide from the inside (for example, carbonated drinking water).
[0047]
In the first embodiment, four exhaust holes are formed in the main body of the external electrode. However, a plurality of exhaust holes other than one or four may be formed. However, it is preferable that a plurality of exhaust holes are provided and the holes are formed at an equal angle with respect to the center of the external electrode.
[0048]
In the first embodiment, an exhaust hole is formed in the main body of the external electrode, but an exhaust groove may be provided. Specifically, as shown in FIGS. 3 and 4, a plurality of, for example, four exhaust grooves 23 are inserted into the PET bottle B of the main body 4 of the external electrode 6 from the end face of the main body 4 of the external electrode 6 on the exhaust pipe 10 side. The main body 4 is pierced at an equal angle (90 °) along the inner surface to be formed. In particular, as shown in FIGS. 3 and 4, one end (upper end) of each of the four exhaust grooves 23 is open at the end surface of the main body 4 of the external electrode 6 on the exhaust pipe 10 side, and the other end (lower end). Is preferably extended to the inner surface portion (for example, a portion corresponding to the shoulder position of the plastic bottle B) of the external electrode 6 below the flange position P at the mouth of the plastic bottle B to be inserted. By piercing the external electrode 6 with such an exhaust groove 23, deformation of the plastic bottle B can be more effectively prevented. If the cross-sectional area of these exhaust grooves 23 is small, it is impeded that the gas between the external electrode 6 and the plastic bottle B is smoothly exhausted through the exhaust grooves 23, while if their cross-sectional area is increased, their exhaust areas are reduced. Plasma is easily generated in the exhaust groove 23. Therefore, it is preferable that the cross-sectional area of each of the exhaust grooves 23 satisfies the following relationship.
[0049]
(S _p / V _p ) ≦ (S _t / V _g )
Where S _p Is the cross-sectional area of the mouth of the plastic bottle, V _p Is the volume of the plastic bottle, S _t Is the cross-sectional area of the exhaust groove, V _g Is the volume of the gap between the external electrode and the plastic bottle.
[0050]
(Second Embodiment)
FIG. 5 is a sectional view showing an apparatus for forming a carbon film on the inner surface of a plastic container according to the second embodiment. In FIG. 5, the same members as those in FIG. 1 referred to in the first embodiment described above are denoted by the same reference numerals, and description thereof will be omitted.
[0051]
In this carbon film forming apparatus, a bias power supply 24 is connected to the external electrode body 4 of the external electrode 6 through a cable 25 and a power supply terminal 26. The matching unit 27 is interposed in the cable 25 between the bias power supply 24 and the power supply terminal 26.
[0052]
The lid 12, which has an insulating ring 27 at the center and is grounded, is air-tightly fixed to the upper flange 9 a of the gas exhaust pipe 10. The housing 28 is mounted on the lid 12.
[0053]
The gas supply pipe 18 also serves as a terminal for high-frequency power, penetrates through the insulating ring 27 of the lid 12 from inside the housing 28, and is inserted into the main body 4 of the external electrode 6 through the gas exhaust pipe 10. I have. The upper end of the gas supply pipe 18 is connected via an insulating joint 30 to the lower end of a gas introduction pipe 29 inserted through the housing 28 from the outside.
[0054]
The flange pipe 31 and the earth shield pipe 32 connected to the lower end of the flange pipe 31 are connected to the gas exhaust pipe 10 and the main body 4 of the external electrode 6 at a position corresponding to the mouth of the plastic bottle B. It is arranged so as to cover the supply pipe 18. The earth shield tube 32 is located in a location corresponding to the mouth of the PET bottle B and in the gas exhaust pipe 10 near this location. The upper end of the flange tube 31 is connected to the back surface of the lid 12. That is, the earth shield tube 32 is connected to the lid 12 grounded through the flange tube 31.
[0055]
The high-frequency power supply 33 is connected to a side surface of the gas supply pipe 18 which also serves as a high-frequency power terminal through a cable 34 and a power supply terminal 35. The matching device 26 is interposed in the cable 34 between the high-frequency power supply 33 and the power supply terminal 35.
[0056]
Next, a method for manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus shown in FIG. 5 will be described.
[0057]
The external electrode bottom member 5, the disk-shaped insulator 7, and the base 3 are removed by a pusher (not shown) to open the bottom of the external electrode body 4. Subsequently, after the plastic container, for example, the plastic bottle B is inserted from the bottom side of the opened external electrode body 4 from the mouth side of the bottle B, the external electrode bottom member 5 is inserted into the bottom side of the external electrode body 4 by a pusher (not shown). By attaching the disk-shaped insulator 7 and the base 3 in this order, the PET bottle B is placed in the internal space of the external electrode body 4 and the external electrode 6 which is the shell of the external electrode bottom member 5 as shown in FIG. Storing Storing. At this time, the PET bottle B is communicated with the exhaust pipe 10 through its mouth.
[0058]
Next, gas inside and outside the exhaust pipe 19 and the plastic bottle B is exhausted through the branch exhaust pipe 11 and the exhaust pipe 10 by an exhaust means (not shown). At this time, as shown in FIG. 1 and FIG. 2, the plurality of, for example, four exhaust holes 13 are formed from the end face of the main body 4 of the external electrode 6 on the exhaust pipe 10 side to the plastic container of the main body 4 in the external electrode 6. Since it is drilled at an equal angle (90 °) with respect to the center of the main body 4 over the inserted inner surface, not only the gas in the PET bottle B but also the outer surface of the PET bottle B and the external electrode 6 are formed. The gas that stays between them is also exhausted through the plurality of exhaust holes 13. As a result, the pressure inside and outside the plastic bottle B is balanced, and deformation of the plastic bottle B due to the pressure difference between the inside and outside can be prevented.
[0059]
In particular, as shown in FIG. 5, one end (upper end) of the four exhaust holes 13 is opened at the end surface of the main body 4 of the external electrode 6 on the exhaust pipe 10 side, and the other end (lower end) is inserted therein. B, an opening is formed on the inner surface portion of the external electrode 6 below the flange position P of the mouth portion (for example, a portion corresponding to the shoulder position of the plastic bottle B), and the cross-sectional area of each of the exhaust holes 13 is set to the above (S _p / V _p ) ≦ (S _e / V _g ), The gas remaining between the outer surface of the plastic bottle B and the main body 4 of the external electrode 6 can also be effectively exhausted through the plurality of exhaust holes 13. By balancing the pressure inside and outside B, the deformation of the PET bottle B due to the pressure difference between inside and outside thereof can be more reliably prevented, and unnecessary plasma can be prevented from being generated in the exhaust hole 13.
[0060]
Next, the medium gas is supplied to the gas flow path 20 of the internal electrode 19 through the gas introduction pipe 29 and the gas supply pipe 18, and is blown into the PET bottle B from the gas blowout hole 21 of the cap 22 attached to the bottom of the internal electrode 19. Let it. This medium gas further flows toward the mouth of the plastic bottle B. Subsequently, the gas supply amount and the gas exhaust amount are balanced, and the inside of the PET bottle B is set to a predetermined gas pressure.
[0061]
Next, bias power is supplied from the bias power supply 24 to the external electrode 6 through the cable 25, the matching device 27, and the power supply terminal 26. Thereafter or at the same time, high-frequency power is supplied from the high-frequency power supply 33 to the gas supply pipe 18 through the cable 34, the matching device 36, and the power supply terminal 35, and the high-frequency power is supplied to the internal electrode 19 through the gas supply pipe 18. . At this time, plasma is generated around the internal electrode 42. Further, since the exhaust pipe 10 located at the information of the external electrode 6 is grounded, a bias voltage is applied from the external electrode 6 to the internal electrode 19 using the exhaust pipe 10 as a reference potential, that is, the generated plasma is Can be applied.
[0062]
As a result, a) a higher electron density can be obtained by using a high-frequency power, especially under a low gas pressure condition, as compared with a high-frequency power, so that the collision frequency with the medium gas is increased and the film forming species density can be increased. B) By adjusting the bias power, the potential difference from the plasma potential can be made variable, so that the ion energy incident on the inner surface of the PET bottle B can be adjusted. C) Since the ion density is proportional to the electron density, use in combination with the above-mentioned adjustment of the potential difference With this, the ion flux incident on the inner surface of the PET bottle B can be controlled. By generating the plasma and drawing the plasma into the external electrode 6 by applying the bias voltage to the internal electrode 19, the bias power was applied to the film forming species obtained when the medium gas was dissociated by the plasma. The inner surface of the PET bottle B in the external electrode 6 can be coated with a uniform carbon film having a uniform thickness at a high speed.
[0063]
After the thickness of the carbon film reaches a predetermined thickness, the supply of the bias power and the high-frequency power from the bias power supply 24 and the high-frequency power supply 33 is stopped, the supply of the medium gas is stopped, and the residual gas is removed. After the gas is evacuated and the gas is evacuated, nitrogen, rare gas, air, or the like is supplied from the gas introduction pipe 29 through the gas supply pipe 18, through the gas flow path 20 of the internal electrode 19, and through the gas outlet 21 of the cap 22. It is supplied into the bottle B, the inside and outside of the PET bottle B is returned to the atmospheric pressure, and the PET bottle coated with the inner carbon film is taken out. After that, the PET bottle B is exchanged according to the above-described order, and the process proceeds to the coating operation of the next PET bottle.
[0064]
As the medium gas, the same gas as described in the first embodiment can be used.
[0065]
The high-frequency power is generally defined as 30 to 300 MHz, but is not limited thereto. The application of these powers may be continuous or intermittent (pulsed).
[0066]
A bias power of 13.56 MHz and 100 to 1000 W is generally used, but is not limited thereto. The application of the bias power may be continuous or intermittent (pulsed).
[0067]
As described above, according to the second embodiment, when the gas inside and outside the plastic bottle B is exhausted through the exhaust pipe 10, not only the gas inside the plastic bottle B but also stays between the external surface of the plastic bottle B and the external electrode 6. The exhaust gas is also exhausted through the plurality of exhaust holes 13 formed in the external electrode 6 shown in FIG. 5, so that the pressure inside and outside the PET bottle B is balanced, and the pressure difference between the inside and outside of the PET bottle B is reduced. The resulting deformation can be prevented. As a result, in the subsequent supply of the medium to the PET bottle B and generation of plasma, the inner surface of the PET bottle B can be coated with a carbon film having a uniform thickness.
[0068]
In addition, by generating plasma and drawing the plasma into the external electrode 6 by applying a bias voltage to the internal electrode 19, the film forming species obtained when the medium gas is dissociated by the plasma is applied with the bias power. The inner surface of the PET bottle B in the external electrode 6 can be coated with a uniform carbon film having a uniform thickness at a high speed.
[0069]
Therefore, it is possible to mass-produce a PET bottle coated with an inner carbon film having an excellent barrier property that prevents transmission of oxygen from the outside and transmission of carbon dioxide from the inside (for example, carbonated drinking water).
[0070]
In addition, unnecessary plasma is similarly generated between the gas supply pipe 18 to which high-frequency power is applied and the exhaust pipe 10 grounded, that is, in the exhaust pipe 10, and the coating efficiency of the carbon film is reduced. For this reason, the earth shield pipe 32 is disposed on the outer periphery of the gas supply pipe 18 so as to be located in the gas exhaust pipe 10 near the mouth of the plastic bottle B, and the earth shield pipe 32 is supported by a flange for supporting the same. By grounding through the pipe 31, even if high-frequency power is supplied to the gas supply pipe 18 penetrating through the inside of the earth shield pipe 32, unnecessary plasma is generated in the exhaust pipe 10 which is a medium gas exhaust path. Can be prevented. As a result, it is possible to prevent the consumption of high-frequency power due to unnecessary plasma generation, so that the regular plasma generation efficiency in the PET bottle B can be increased, and the coating speed of the carbon film can be improved.
[0071]
In the second embodiment, four exhaust holes are formed in the main body of the external electrode. However, it is permissible to form a plurality of exhaust holes other than one or four. However, it is preferable that a plurality of exhaust holes are provided and the holes are formed at an equal angle with respect to the center of the external electrode.
[0072]
In the second embodiment, the exhaust hole is formed in the main body of the external electrode. However, the exhaust groove shown in FIGS. 3 and 4 may be provided.
[0073]
(Third embodiment)
FIG. 6 is a sectional view showing an apparatus for forming a carbon film on the inner surface of a plastic container according to the third embodiment.
[0074]
A cylindrical support member 42 having upper and lower flanges 41 a and 41 b is mounted on an annular base 43. A cylindrical external electrode body 44 made of metal is disposed inside the support member 42. A disk-shaped external electrode bottom member 45 made of metal is detachably attached to the bottom of the external electrode 44. The external electrode body 44 and the external electrode bottom member 45 constitute a bottomed cylindrical external electrode 46 having a space large enough to accommodate a plastic container (for example, a PET bottle) B on which a carbon film is formed. Note that a disc-shaped insulator 47 is disposed between the base 43 and the external electrode bottom member 45.
[0075]
The external electrode bottom member 45, the disc-shaped insulator 47, and the base 43 move up and down integrally with the external electrode body 4 by a pusher (not shown) to open and close the bottom of the external electrode body 4. I do.
[0076]
A cylindrical spacer 49 made of a dielectric material having a cavity 48 formed by combining a cylinder and a truncated cone corresponding to the mouth and shoulder of the plastic bottle B inserted therein is formed by the main body of the external electrode 46. It is inserted in the upper part of 44. The spacer 49 is fixed by a screw (not shown) screwed from an annular insulating member to be described later mounted thereon. When the plastic bottle B is inserted from the bottom side of the external electrode main body 44 by inserting and fixing the columnar spacer 49 on the upper part of the main body 44 in the external electrode 46, the mouth and shoulder of the plastic bottle B are inserted. The part is accommodated in the cavity 48 of the spacer 49, and the other parts of the PET bottle B are accommodated in the external electrode 46.
[0077]
Examples of the dielectric material forming the spacer 49 include plastic or ceramic. Various plastics can be used, but a fluororesin such as polytetrafluoroethylene, which has a particularly low high-frequency loss and excellent heat resistance, is preferable. As the ceramic, alumina or steatite having low high-frequency loss or macor having high machinability is preferable.
[0078]
The annular insulating member 50 is mounted on the upper surface of the external electrode 46 such that the upper surface of the annular insulating member 50 is flush with the upper flange 41 a of the tubular support member 42. A gas exhaust pipe 52 having upper and lower flanges 51 a and 51 b is mounted on the upper flange 41 a of the support member 42 and the upper surface of the annular insulating member 50. This exhaust pipe 52 is grounded. The gas exhaust pipe 52 is fixed to the support member 42 by screwing a screw (not shown) from the lower flange 51b of the exhaust pipe 52 to the upper flange 41a of the support member 42. Further, by screwing a screw (not shown) from the lower flange 51b of the exhaust pipe 52 to the main body 44 of the external electrode 46 through the annular insulating section 50, the exhaust pipe 52 is connected to the annular insulating member 50 and the external electrode. At the same time, the annular insulating member 50 is fixed to the external electrode 46. The fixing of the exhaust pipe 52 to the annular insulating member 50 and the external electrode 46 is a mounting structure in which the exhaust pipe 52 and the external electrode 46 are not electrically connected by screws. The branch gas exhaust pipe 53 is connected to the side wall of the gas exhaust pipe 52, and exhaust equipment such as a vacuum pump (not shown) is attached to the other end. The lid 54 is attached to the upper flange 51a of the exhaust pipe 52.
[0079]
As shown in FIG. 6, a plurality of, for example, four exhaust holes 55 are formed from the end face of the spacer 49 on the exhaust pipe 52 side to the inner surface of the spacer 49 into which the plastic bottle B is inserted. In particular, as shown in FIG. 6, one end (upper end) of each of the exhaust holes 55 is opened at the end surface of the spacer 49 on the exhaust pipe 52 side, and the other end (lower end) of the mouth of the PET bottle B into which the other end (lower end) is inserted. It is preferable that an opening is provided in an inner surface portion of the spacer 49 below the flange position P (for example, a portion corresponding to a shoulder position of the plastic bottle B). If the cross-sectional area of these exhaust holes 55 is small, it is impeded that the gas between the external electrode 6 and the plastic bottle B is smoothly exhausted through the exhaust holes 55. Plasma is easily generated in the exhaust holes 55. Therefore, it is preferable that the cross-sectional area of each of the exhaust holes 55 satisfies the following relationship.
[0080]
(S _p / V _p ) ≦ (S _e / V _G )
Where S _p Is the cross-sectional area of the mouth of the plastic bottle, V _p Is the volume of the plastic bottle, S _e Is the cross-sectional area of the exhaust hole, V _G Is the volume of the gap between the external electrode and the spacer and the plastic bottle.
[0081]
For example, a high-frequency power supply 56 that outputs high-frequency power having a frequency of 13.56 MHz is connected to the main body 44 of the external electrode 46 through a cable 57 and a power supply terminal 58. The matching device 59 is interposed in the cable 57 between the high-frequency power supply 56 and the power supply terminal 58.
[0082]
The gas supply pipe 60 penetrates through the lid 54 and is inserted through the gas exhaust pipe 52 into the body 44 of the external electrode 46 at a location corresponding to the mouth of the plastic bottle B. The substantially cylindrical internal electrode 61 is disposed in the plastic bottle B inserted into the external electrode 46 over substantially the entire length of the plastic bottle B in the longitudinal direction, and the upper end thereof is located at the lower end of the gas supply pipe 60. It is attached detachably. The internal electrode 61 has a gas flow passage 62 cut out in the center axis, and a cap 64 having a gas blowout hole 63 for blowing out a medium gas at the bottom portion is detachably attached.
[0083]
The gas outlet may be opened in the lower side wall of the internal electrode 61 so as to communicate with the gas flow channel 62. In this case, it is preferable that the gas blowing hole be opened in a side surface region within a range from the bottom of the internal electrode 61 to 25% of the length inserted into the plastic bottle B.
[0084]
The diameter of the internal electrode 61 is equal to or smaller than the diameter of the base of the bottle B, and the length is a length that can be inserted over substantially the entire length of the plastic bottle B in the longitudinal direction. As a guide of the length, the ratio to the total length of the PET bottle B is set to be about {1-D / (2L)}. Here, D represents the inner diameter of the PET bottle, L represents the total length of the PET bottle, and L> (D / 2).
[0085]
The internal electrode 61 is made of a heat-resistant metal material such as tungsten or stainless steel, but may be made of aluminum. If the surface of the internal electrode 19 is smooth, the carbon film deposited on the surface of the internal electrode 61 may be easily peeled off. For this reason, it is preferable that the surface of the internal electrode 61 be sandblasted in advance to increase the surface roughness so that the carbon film deposited on the surface is hardly peeled off.
[0086]
Next, a method of manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus shown in FIG. 6 will be described.
[0087]
The external electrode bottom member 45, the disc-shaped insulator 47 and the base 43 are removed by a pusher (not shown) to open the bottom of the external electrode body 44. Subsequently, after the plastic container, for example, the plastic bottle B is inserted from the bottom side of the opened external electrode body 44 to the mouth side of the bottle B, the external electrode bottom member 5 is placed on the bottom side of the external electrode body 44 by a pusher (not shown). By attaching the disk-shaped insulator 7 and the base 3 in this order, as shown in FIG. 6, the shoulder portion from the mouth of the plastic bottle B into the cavity 48 of the columnar spacer 49 made of a dielectric material. The side from the shoulder to the bottom of the bottle B is housed in the external electrode 46. At this time, the PET bottle B is communicated with the exhaust pipe 52 through its mouth.
[0088]
Next, gas inside the exhaust pipe 52 and inside and outside the PET bottle B is exhausted through a branch exhaust pipe 53 and an exhaust pipe 52 by exhaust means (not shown). At this time, as shown in FIG. 6, the plurality of, for example, four exhaust holes 55 extend from the end face of the spacer 49 on the exhaust pipe 52 side to the inner surface of the spacer 49 into which the plastic bottle B is inserted. Are pierced at an equal angle (90 °) with respect to the center of the plastic bottle B, so that not only the gas inside the plastic bottle B but also stays between the outer surface of the plastic bottle B and the spacer 49 and the external electrode 46. Gas is also exhausted through the plurality of exhaust holes 55. As a result, the pressure inside and outside the plastic bottle B is balanced, and deformation of the plastic bottle B due to the pressure difference between the inside and outside can be prevented.
[0089]
In particular, as shown in FIG. 6, one end (upper end) of the four exhaust holes 55 is opened at the end surface of the spacer 49 on the exhaust pipe 52 side, and the other end (lower end) of the PET bottle B is inserted. The opening of the inner surface of the spacer 49 below the flange position P (for example, the portion corresponding to the shoulder position of the PET bottle B), and the cross-sectional area of each of the exhaust holes 55 is (S _p / V _p ) ≦ (S _e / V _G By setting so as to satisfy the relationship of (3), the gas remaining between the outer surface of the PET bottle B and the external electrode 46 can also be effectively exhausted through the plurality of exhaust holes 55. Can be more reliably prevented from deforming the PET bottle B due to a pressure difference between the inside and outside thereof, and unnecessary plasma can be prevented from being generated in the exhaust hole 55.
[0090]
Next, a medium gas is supplied to the gas flow channel 62 of the internal electrode 61 through the gas supply pipe 60, and is blown into the plastic bottle B from the gas blowing hole 63 of the cap 64 attached to the bottom of the internal electrode 61. This medium gas further flows toward the mouth of the plastic bottle B. Subsequently, the gas supply amount and the gas exhaust amount are balanced, and the inside of the PET bottle B is set to a predetermined gas pressure.
[0091]
Next, high-frequency power having a frequency of, for example, 13.56 MHz is supplied from the high-frequency power supply 56 to the main body 44 of the external electrode 46 through the cable 57, the matching unit 59, and the power supply terminal 58. At this time, plasma is generated around the internal electrode 61. Due to the generation of the plasma, the medium gas is dissociated by the plasma, and the inner surface of the PET bottle B in the outer electrode 46 and the spacer 49 is coated with a uniform carbon film having a uniform thickness.
[0092]
After the thickness of the carbon film reached a predetermined thickness, the supply of the high-frequency power from the high-frequency power supply 56 was stopped, the supply of the medium gas was stopped, the residual gas was exhausted, and the exhaust of the gas was stopped. Thereafter, nitrogen, rare gas, air, or the like is supplied into the plastic bottle B through the gas supply pipe 60, the gas flow path 62 of the internal electrode 61, and the gas blowing hole 63 of the cap 64. And take out the PET bottle coated with the inner carbon film. After that, the PET bottle B is exchanged according to the above-described order, and the process proceeds to the coating operation of the next PET bottle.
[0093]
As the medium gas, the same gas as in the first embodiment can be used.
[0094]
The high-frequency power generally has a frequency of 13.56 MHz and a power of 100 to 1000 W, but is not limited thereto.
[0095]
As described above, according to the third embodiment, when the gas inside and outside the plastic bottle B is exhausted through the exhaust pipe 52, not only the gas inside the plastic bottle B but also the external surface of the plastic bottle B and the external electrode 46 and the spacer 49 By exhausting the gas remaining in the space through the plurality of exhaust holes 55 formed in the spacer 49 shown in FIG. 6, the pressure inside and outside the PET bottle B is balanced, and the pressure inside and outside the PET bottle B is reduced. Deformation due to the difference can be prevented. As a result, a carbon film having a uniform thickness can be coated on the inner surface of the PET bottle B by the subsequent supply of the medium to the PET bottle B and generation of plasma.
[0096]
Further, by inserting and fixing a columnar spacer 49 made of a dielectric material having a cavity 48 on the upper portion of the external electrode 46, not only the inner surface from the shoulder to the bottom of the PET bottle B but also the generation of the plasma can be achieved. A carbon film having a uniform thickness can be coated on the inner surface of the shoulder from the mouth of the PET bottle B facing the spacer 49 made of the dielectric material.
[0097]
Therefore, it is possible to mass-produce an inner carbon film-coated PET bottle having an excellent barrier property and preventing permeation of oxygen from the outside and permeation of carbon dioxide from the inside (for example, carbonated drinking water).
[0098]
Moreover, although the shape of the member covering the mouth and the periphery of the shoulder of the PET bottle B is complicated, by forming the spacer 49 corresponding to these members from a dielectric material such as injection-moldable plastic, for example, It can be easily manufactured as compared with the case where all the members including these members are formed by external electrodes as in the related art. Further, the weight of the entire apparatus can be reduced as compared with the conventional case in which all parts including these members are formed of external electrodes using a conductive material such as metal.
[0099]
Further, by forming the spacer 49 from a dielectric material such as plastic or soft ceramic, it is possible to prevent the complicated mouth portion and shoulder portion of the plastic bottle B from being damaged at the time of contact. it can.
[0100]
In the third embodiment, four exhaust holes are formed in the spacer. However, it is permissible to form one or more than four exhaust holes. However, it is preferable that a plurality of exhaust holes are provided and the holes are formed at an equal angle with respect to the center of the spacer.
[0101]
In the third embodiment, an exhaust hole is formed in the spacer, but an exhaust groove may be provided. Specifically, as shown in FIG. 7, a plurality of, for example, four exhaust grooves 65 are formed from the end face of the spacer 49 on the exhaust pipe 52 side along the inner surface of the spacer 49 into which the plastic bottle B is inserted. At an equal angle (90 °) with respect to In particular, as shown in FIG. 7, one end (upper end) of these exhaust holes 65 is opened at the end face of the spacer 49 on the exhaust pipe 52 side, and the other end (lower end) of the mouth of the PET bottle B into which the other end (lower end) is inserted. It is preferable that the spacer 49 be extended to an inner surface portion of the spacer 49 below the flange position P (for example, a portion corresponding to a shoulder position of the plastic bottle B). By forming the exhaust groove 55 having such a configuration in the spacer 49, the deformation of the plastic bottle B can be more effectively prevented. If the cross-sectional area of these exhaust grooves 65 is small, it is impeded that the gas between the external electrode 46 and the spacer 49 and the plastic bottle B is smoothly exhausted through the exhaust groove 65, while their cross-sectional area increases. Then, plasma is easily generated in the exhaust grooves 65. Therefore, it is preferable that the cross-sectional area of each of the exhaust grooves 65 satisfies the following relationship.
[0102]
(S _p / V _p ) ≦ (S _t / V _G )
Where S _p Is the cross-sectional area of the mouth of the plastic bottle, V _p Is the volume of the plastic bottle, S _t Is the cross-sectional area of the exhaust groove, V _G Is the volume of the gap between the external electrode and the spacer and the plastic bottle.
[0103]
In the third embodiment, a cylindrical spacer 49 made of a dielectric material having a cavity 48 is inserted and fixed above the external electrode 46 from the mouth of the PET bottle B to the shoulder. A thin film made of a dielectric material may extend from the shoulder to the bottom.
[0104]
(Fourth embodiment)
FIG. 8 is a sectional view showing an apparatus for forming a carbon film on the inner surface of a plastic container according to the fourth embodiment. In FIG. 8, the same members as those in FIG. 6 referred to in the third embodiment described above are denoted by the same reference numerals, and description thereof will be omitted.
[0105]
In the carbon film forming apparatus, a bias power supply 66 is connected to the external electrode body 44 of the external electrode 46 through a cable 67 and a power supply terminal 68. The matching device 69 is provided on the cable 67 between the bias power source 66 and the power supply terminal 68.
[0106]
A cover 54 having an insulating ring 70 at the center and grounded is air-tightly fixed to an upper flange 51 a of the gas exhaust pipe 52. The housing 71 is mounted on the lid 54.
[0107]
The gas supply pipe 60 also serves as a high-frequency power terminal, penetrates through the insulating ring 70 of the lid 54 from inside the housing 71, and is inserted into the spacer 49 in the external electrode 46 through the gas exhaust pipe 52. ing. The upper end of the gas supply pipe 60 is connected via an insulating joint 73 to the lower end of a gas introduction pipe 72 inserted through the housing 71 from the outside.
[0108]
The flange pipe 74 and the earth shield pipe 75 connected to the lower end of the flange pipe 74 are arranged so as to cover the gas exhaust pipe 52 and the gas supply pipe 60 located in the spacer 49. The earth shield tube 75 is located in the spacer 49 and in the gas exhaust pipe 52 near the spacer 49. The upper end of the flange tube 74 is connected to the back surface of the lid 54. That is, the earth shield tube 75 is connected to the lid 54 grounded through the flange tube 74.
[0109]
The high-frequency power supply 76 is connected to the side of the gas supply pipe 60 which also serves as a terminal for high-frequency power through a cable 77 and a power supply terminal 78. The matching device 79 is interposed in the cable 77 between the high-frequency power supply 76 and the power supply terminal 78.
[0110]
Next, a method for manufacturing a plastic container coated with an inner carbon film using the carbon film forming apparatus shown in FIG. 8 will be described.
[0111]
The external electrode bottom member 45, the disc-shaped insulator 47 and the base 43 are removed by a pusher (not shown) to open the bottom of the external electrode body 44. Subsequently, after the plastic container, for example, the plastic bottle B is inserted from the bottom side of the opened external electrode body 44 to the mouth side of the bottle B, the external electrode bottom member 5 is placed on the bottom side of the external electrode body 44 by a pusher (not shown). By attaching the disk-shaped insulator 7 and the base 3 in this order, as shown in FIG. 6, the shoulder portion from the mouth of the plastic bottle B into the cavity 48 of the columnar spacer 49 made of a dielectric material. The side from the shoulder to the bottom of the bottle B is housed in the external electrode 46. At this time, the PET bottle B is communicated with the exhaust pipe 52 through its mouth.
[0112]
Next, gas inside the exhaust pipe 52 and inside and outside the PET bottle B is exhausted through a branch exhaust pipe 53 and an exhaust pipe 52 by exhaust means (not shown). At this time, as shown in FIG. 6, the plurality of, for example, four exhaust holes 55 extend from the end face of the spacer 49 on the exhaust pipe 10 side to the inner surface of the spacer 49 into which the plastic bottle B is inserted. Are pierced at an equal angle (90 °) with respect to the center of the plastic bottle B, so that not only the gas inside the plastic bottle B but also stays between the outer surface of the plastic bottle B and the spacer 49 and the external electrode 46. Gas is also exhausted through the plurality of exhaust holes 55. As a result, the pressure inside and outside the plastic bottle B is balanced, and deformation of the plastic bottle B due to the pressure difference between the inside and outside can be prevented.
[0113]
In particular, as shown in FIG. 8, one end (upper end) of the four exhaust holes 55 is opened at the end surface of the spacer 49 on the exhaust pipe 52 side, and the other end (lower end) of the PET bottle B is inserted. The opening of the inner surface of the spacer 49 below the flange position P (for example, the portion corresponding to the shoulder position of the PET bottle B), and the cross-sectional area of each of the exhaust holes 55 is (S _p / V _p ) ≦ (S _e / V _G By setting so as to satisfy the relationship of (3), the gas remaining between the outer surface of the PET bottle B and the external electrode 46 can also be effectively exhausted through the plurality of exhaust holes 55. Can be more reliably prevented from deforming the PET bottle B due to a pressure difference between the inside and outside thereof, and unnecessary plasma can be prevented from being generated in the exhaust hole 55.
[0114]
Next, the medium gas is supplied to the gas flow path 62 of the internal electrode 61 through the gas introduction pipe 72 and the gas supply pipe 60, and is blown into the PET bottle B from the gas blowout hole 63 of the cap 64 attached to the bottom of the internal electrode 61. Let it. This medium gas further flows toward the mouth of the plastic bottle B. Subsequently, the gas supply amount and the gas exhaust amount are balanced, and the inside of the PET bottle B is set to a predetermined gas pressure.
[0115]
Next, bias power is supplied from the bias power supply 66 to the external electrode 46 through the cable 67, the matching device 69, and the power supply terminal 68. Thereafter or at the same time, high-frequency power is supplied from the high-frequency power supply 76 to the gas supply pipe 60 through the cable 77, the matching device 79, and the power supply terminal 78, and the high-frequency power is supplied to the internal electrode 61 through the gas supply pipe 60. . At this time, plasma is generated around the internal electrode 61. Further, the earth shield tube 75 is arranged on the outer periphery of the gas supply tube 60 so as to be located in the spacer 49 and in the gas exhaust tube 52 near the spacer 49, and is grounded through the flange tube 74. A bias voltage can be applied from the external electrode 46 toward the internal electrode 61, that is, toward the generated plasma, using the earth shield tube 75 as a reference potential.
[0116]
As a result, a) a higher electron density can be obtained by using a high-frequency power, especially under a low gas pressure condition, as compared with a high-frequency power, so that the collision frequency with the medium gas is increased and the film forming species density can be increased. B) By adjusting the bias power, the potential difference from the plasma potential can be made variable, so that the ion energy incident on the inner surface of the PET bottle B can be adjusted. C) Since the ion density is proportional to the electron density, use in combination with the above-mentioned adjustment of the potential difference With this, the ion flux incident on the inner surface of the PET bottle B can be controlled. By generating the plasma and drawing the plasma into the external electrode 46 by applying the bias voltage to the internal electrode 61, the bias power was applied to the film forming species obtained when the medium gas was dissociated by the plasma. The inner surface of the PET bottle B in the external electrode 46 can be coated with a uniform carbon film having a uniform thickness at a high speed.
[0117]
After the thickness of the carbon film reaches a predetermined thickness, the supply of the bias power and the high-frequency power from the bias power supply 66 and the high-frequency power supply 76 is stopped, the supply of the medium gas is stopped, and the residual gas is removed. After the gas is evacuated and the gas is evacuated, nitrogen, rare gas, air, or the like is supplied from the gas introduction pipe 72 through the gas supply pipe 60 through the gas flow path 62 of the internal electrode 61 and the gas outlet 63 of the cap 64. It is supplied into the bottle B, the inside and outside of the PET bottle B is returned to the atmospheric pressure, and the PET bottle coated with the inner carbon film is taken out. After that, the PET bottle B is exchanged according to the above-described order, and the process proceeds to the coating operation of the next PET bottle.
[0118]
As the medium gas, the same gas as described in the first embodiment can be used.
[0119]
The high-frequency power is generally defined as 30 to 300 MHz, but is not limited thereto. The application of these powers may be continuous or intermittent (pulsed).
[0120]
A bias power of 13.56 MHz and 100 to 1000 W is generally used, but is not limited thereto. The application of the bias power may be continuous or intermittent (pulsed).
[0121]
As described above, according to the fourth embodiment, when the gas inside and outside the plastic bottle B is exhausted through the exhaust pipe 52, not only the gas inside the plastic bottle B but also the outside surface of the plastic bottle B and the external electrode 46 and the spacer 49 By evacuating the gas remaining in the space through the plurality of exhaust holes 55 formed in the spacer 49 shown in FIG. 8, the pressure inside and outside the PET bottle B is balanced, and the pressure inside and outside the PET bottle B is reduced. Deformation due to the difference can be prevented. As a result, a carbon film having a uniform thickness can be coated on the inner surface of the PET bottle B by the subsequent supply of the medium to the PET bottle B and generation of plasma.
[0122]
Further, by generating plasma and drawing the plasma into the external electrode 56 by applying a bias voltage to the internal electrode 61, the film forming species obtained when the medium gas is dissociated by the plasma is applied with the bias power. The inner surface of the PET bottle B in the outer electrode 46 can be coated with a uniform carbon film having a uniform thickness at a high speed.
[0123]
Therefore, it is possible to mass-produce a PET bottle coated with an inner carbon film having an excellent barrier property that prevents transmission of oxygen from the outside and transmission of carbon dioxide from the inside (for example, carbonated drinking water).
[0124]
In addition, unnecessary plasma is similarly generated between the gas supply pipe 60 to which high-frequency power is applied and the exhaust pipe 52 grounded, that is, in the exhaust pipe 52, and the coating efficiency of the carbon film is reduced. For this reason, the earth shield tube 75 is arranged on the outer periphery of the gas supply tube 60 so as to be located in the gas exhaust tube 52 near the mouth of the plastic bottle B, and the earth shield tube 75 is connected to the flange for supporting the same. By grounding through the pipe 74, even if high-frequency power is supplied to the gas supply pipe 60 penetrating through the inside of the earth shield pipe 75, unnecessary plasma is generated in the exhaust pipe 52 which is a medium gas exhaust path. Can be prevented. As a result, it is possible to prevent the consumption of high-frequency power due to unnecessary plasma generation, so that the regular plasma generation efficiency in the PET bottle B can be increased, and the coating speed of the carbon film can be improved.
[0125]
In the fourth embodiment, four exhaust holes are formed in the main body of the external electrode. However, a plurality of exhaust holes other than one or four may be formed. However, it is preferable that a plurality of exhaust holes are provided and the holes are formed at an equal angle with respect to the center of the external electrode.
[0126]
In the fourth embodiment, the exhaust hole is formed in the main body of the external electrode. However, the exhaust groove shown in FIG. 7 may be provided.
[0127]
In the fourth embodiment, the cylindrical spacer 49 made of a dielectric material having the cavity 48 is inserted and fixed above the external electrode 46 from the mouth of the PET bottle B to the shoulder. A thin film made of a dielectric material may extend from the shoulder of B to the bottom.
[0128]
In the fourth embodiment, the shape of the earth shield tube 75 is not limited to the shape in which the lower end is located near the mouth of the plastic bottle B as shown in FIG. The length of the internal electrode may be effectively shortened by being located close to the vicinity.
[0129]
【The invention's effect】
As described above in detail, according to the present invention, when coating a carbon film on the inner surface of a plastic container, the deformation of the container can be prevented, and a carbon film having a uniform thickness is coated on the entire inner surface of the plastic container. It is possible to provide an apparatus for forming a carbon film on the inner surface of a plastic container, which is capable of performing the above.
[0130]
Further, according to the present invention, it is possible to provide a method capable of manufacturing a plastic container having an inner surface coated with a carbon film having a uniform film thickness and having an excellent barrier property against oxygen and carbon dioxide.
[0131]
Further, according to the present invention, when coating the carbon film on the inner surface of the plastic container, it is possible to prevent deformation of the container, it is possible to coat the entire inner surface of the plastic container with a carbon film having a uniform thickness, It is also possible to provide an apparatus for forming a carbon film on the inner surface of a plastic container capable of performing high-speed coating.
[0132]
Further, according to the present invention, it is possible to provide a method capable of mass-producing a plastic container having an inner surface coated with a carbon film having a uniform film thickness at a high speed and having an excellent barrier property against oxygen and carbon dioxide. .
[Brief description of the drawings]
FIG. 1 is a sectional view showing an apparatus for forming a carbon film on an inner surface of a plastic container according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing an external electrode of FIG. 1;
FIG. 3 is a sectional view showing a modification of the apparatus for forming a carbon film on the inner surface of a plastic container according to the first embodiment of the present invention.
FIG. 4 is a perspective view showing an external electrode of FIG. 3;
FIG. 5 is a sectional view showing an apparatus for forming a carbon film on an inner surface of a plastic container according to a second embodiment of the present invention.
FIG. 6 is a sectional view showing an apparatus for forming a carbon film on an inner surface of a plastic container according to a third embodiment of the present invention.
FIG. 7 is a sectional view showing a modification of the apparatus for forming a carbon film on the inner surface of a plastic container according to the third embodiment of the present invention.
FIG. 8 is a sectional view showing an apparatus for forming a carbon film on an inner surface of a plastic container according to a fourth embodiment of the present invention.
FIG. 9 is a cross-sectional view showing a conventional apparatus for forming a carbon film on the inner surface of a plastic container.
[Explanation of symbols]
2, 42: support member, 4, 44: external electrode body, 5, 45: external electrode bottom member, 6, 46: external electrode, 10, 52: exhaust pipe, 13, 55: exhaust hole, 14, 56: high frequency Power supply, 18, 60: gas supply pipe, 19, 61: internal electrode, 21, 63: gas blowing hole, 23, 65: exhaust groove, B: plastic bottle, 24, 66: bias power supply, 31, 75: ground Shield tube, 33, 76 ... high frequency power supply, 49 ... cylindrical spacer.

Claims (10)

An external electrode having a size that surrounds the outer periphery of the container when the plastic container that is the object to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the external electrode on the exhaust pipe side to an inner surface of the external electrode into which the plastic container is inserted;
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the internal electrode,
A high-frequency power supply connected to the external electrode,
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising: In producing an inner carbon film-coated plastic container using the carbon film forming apparatus according to claim 1,
(A) inserting a plastic container as an object to be processed into an external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) exhausting gas in the container through the exhaust pipe by exhaust pipe means, and exhausting gas between the outer surface of the container and the external electrode from an exhaust hole or exhaust groove formed in the external electrode; After exhausting through the pipe, a medium gas is supplied to the internal electrode by a gas supply means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to pass a predetermined gas through the exhaust pipe including the plastic container. Setting the pressure;
(D) supplying a high-frequency power from a high-frequency power source to the external electrode to generate plasma around the internal electrode located in the plastic container, and dissociate the medium gas by the plasma to form a carbon film on the inner surface of the plastic container; And a method of producing a plastic container coated with an inner carbon film. An external electrode having a size surrounding the container when the plastic container that is the object to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the external electrode on the exhaust pipe side to an inner surface of the external electrode into which the plastic container is inserted;
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the gas supply pipe,
A high-frequency power supply connected to the gas supply pipe,
A bias power supply connected to the external electrode;
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising: In producing an inner carbon film-coated plastic container using the carbon film forming apparatus according to claim 3,
(A) inserting a plastic container as an object to be processed into an external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) exhausting gas in the container through the exhaust pipe by exhaust pipe means, and exhausting gas between the outer surface of the container and the external electrode from an exhaust hole or exhaust groove formed in the external electrode; After exhausting through a pipe, a medium gas is supplied to the internal electrode from the gas supply pipe means, and a medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to evacuate the inside of the exhaust pipe including the plastic container. Setting a gas pressure of
(D) applying high-frequency power from a bias power supply to the external electrode, supplying high-frequency power from the high-frequency power supply to the internal electrode, and generating plasma in the plastic container; Dissociating and coating a carbon film on the inner surface of the plastic container. One end of the exhaust hole is opened at an end surface of the external electrode on the exhaust pipe side, and the other end is opened at an inner surface portion of the external electrode below a flange position of a mouth portion of a plastic container into which the external electrode is inserted. The apparatus for forming a carbon film on the inner surface of a plastic container according to claim 1 or 3, wherein: An external electrode having a size surrounding the container when the plastic container that is the object to be processed is inserted,
A spacer made of a dielectric material interposed between at least the mouth and shoulders of the container and the external electrode when the plastic container as the object to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An internal electrode that is inserted from the exhaust pipe side into the plastic container in the external electrode, is connected to the ground side, and is provided with a gas blowing hole for blowing out a medium gas,
An exhaust hole or an exhaust groove pierced from an end surface of the spacer on the exhaust pipe side to an inner surface of the spacer into which the plastic container is inserted,
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the internal electrode,
A high-frequency power supply connected to the external electrode,
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising: In producing an inner carbon film-coated plastic container using the carbon film forming apparatus according to claim 6,
(A) A plastic container to be processed is placed in an external electrode and a spacer made of a dielectric material, at least the outer periphery of the mouth and shoulder of the container is surrounded by the spacer, and the other parts of the container are Inserting the outer periphery so as to be surrounded by the external electrode;
(B) Inserting the internal electrode provided with the gas blowout hole into the plastic container from an exhaust pipe attached to the end surface of the external electrode on the side where the mouth of the container is located via an insulating member. Process and
(C) The gas in the container is exhausted through the exhaust pipe by an exhaust pipe means, and gas between the outer surface of the container and the external electrode and the spacer is discharged from an exhaust hole or an exhaust groove formed in the spacer. After exhausting through the exhaust pipe, a medium gas is supplied to the internal electrode by gas supply means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode so that the inside of the exhaust pipe including the inside of the plastic container is predetermined. Setting a gas pressure of
(D) supplying a high-frequency power from a high-frequency power source to the external electrode to generate plasma around the internal electrode located in the plastic container, and dissociate the medium gas by the plasma to form a carbon film on the inner surface of the plastic container; And a method of producing a plastic container coated with an inner carbon film. An external electrode having a size surrounding the container when the plastic container that is the object to be processed is inserted,
A spacer made of a dielectric material interposed between the external electrode and at least the mouth and shoulders of the container when the plastic container that is to be processed is inserted,
An exhaust pipe attached via an insulating member to an end surface of the external electrode on the side where the mouth of the container is located,
An exhaust hole or an exhaust groove pierced from an end surface of the spacer on the exhaust pipe side to an inner surface of the spacer into which the plastic container is inserted,
An internal electrode which is inserted into the plastic container in the external electrode and has a gas blowing hole for blowing out a medium gas,
A gas supply pipe having one end connected to the internal electrode and the other end also serving as a power supply terminal extended to the exhaust pipe side;
An earth shield tube which is arranged at least on the outer periphery of the gas supply pipe portion located in the exhaust pipe near the mouth of the container and near the mouth of the container, and is grounded.
Exhaust means attached to the exhaust pipe,
Gas supply means for supplying a medium gas to the gas supply pipe,
A high-frequency power supply connected to the gas supply pipe,
A bias power supply connected to the external electrode;
An apparatus for forming a carbon film on the inner surface of a plastic container, comprising: In producing an inner carbon film-coated plastic container using the carbon film forming apparatus according to claim 8,
(A) A plastic container to be processed is placed in an external electrode and a spacer made of a dielectric material, at least the outer periphery of the mouth and shoulder of the container is surrounded by the spacer, and the other parts of the container are Inserting the outer periphery so as to be surrounded by the external electrode;
(B) A gas supply pipe having a grounded earth shield disposed on the outer periphery thereof is connected, and an internal electrode provided with a gas blowing hole is provided with an insulating member on an end face of the external electrode on the side where the mouth of the container is located. Inserting the inside of the plastic container from the exhaust pipe attached via,
(C) The gas in the container is exhausted through the exhaust pipe by an exhaust pipe means, and gas between the outer surface of the container and the external electrode and the spacer is discharged from an exhaust hole or an exhaust groove formed in the spacer. After exhausting through the exhaust pipe, a medium gas is supplied to the internal electrode from the gas supply pipe means, and the medium gas is blown into the plastic container from a gas blowout hole of the internal electrode to exhaust gas including the inside of the plastic container. Setting to a predetermined gas pressure,
(D) applying high frequency power from a bias power source to the external electrode and supplying high frequency power from the high frequency power source to the internal electrode through the gas supply pipe to generate plasma in the plastic container; Coating the inner surface of the plastic container with a carbon film by dissociating the medium gas according to the method described above. The exhaust hole is characterized in that one end thereof is opened at the end face on the exhaust pipe side of the spacer, and the other end is opened at the inner surface portion of the spacer below the flange position of the mouth of the plastic container into which the spacer is inserted. 9. The apparatus for forming a carbon film on the inner surface of a plastic container according to claim 6 or 8.

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