JPH0475776B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a plasma processing apparatus for sheet-like materials,
For details, in a vacuum container in a plasma atmosphere,
This invention relates to a device that performs low-temperature plasma treatment by placing a sheet material along the outer peripheral surface of a rotating drum-shaped discharge electrode.

[Prior Art] In recent years, plasma treatment has attracted attention as a treatment method for improving the chemical, physical, mechanical, optical or electrical properties or surface structure of sheet materials such as plastic films and fabrics. . In other words, plasma treatment can improve the adhesion, friction properties, texture, gloss or color fastness of sheet materials, or improve the antistatic properties, surface hardening, roughening, anti-blocking, or darkening of dyed materials. It is known that this can be achieved (for example,
57-18737, JP-A-60-149441).

Conventionally, this type of plasma processing apparatus for sheet-like materials has a drum-shaped discharge electrode fixed to a rotating shaft that passes through the vacuum container, and a rod-shaped discharge electrode facing the drum-shaped discharge electrode, which is provided inside the vacuum container. . and,
Since the vacuum container is insulated from the electrical circuit connecting the two discharge electrodes, plasma discharge from the two discharge electrodes to the vacuum container is prevented, thereby preventing wastage of power.

[Problems to be solved by the invention] However, the plasma processing apparatus for sheet-like materials is
Due to the wide range of sheet materials to be treated,
Generally, the equipment is large-scale, so in order for this to be adopted industrially, it is necessary to have a processing capacity commensurate with the large equipment cost. In other words, originally
It is necessary to further increase the large input power of the plasma processing apparatus that creates the plasma atmosphere and increase the plasma density to improve the processing capacity. However, in a vacuum vessel in a plasma atmosphere with low electrical resistance, if the above input is increased, a locally large amount of electricity will be generated between the vacuum vessel and the electric discharge circuits that are insulated from each other inside the vacuum vessel. As a result, narrow corners, such as the area between the rotating shaft passing through the vacuum vessel and the vacuum vessel adjacent to this rotating shaft, are insufficiently insulated, and current flows to the vacuum vessel side. , the inner wall of the vacuum vessel emits light, and an instantaneous abnormal arc discharge occurs. Therefore, the plasma discharge state becomes unstable and continuous operation is not possible.

This invention was made in view of the above-mentioned conventional problems, and allows continuous operation with large electric power flowing.
That is, the object is to provide a plasma processing apparatus for sheet-like materials that can be used industrially.

[Means for Solving the Problems] In order to achieve the above object, the sheet material plasma processing apparatus of the present invention first includes a vacuum container that is
It is insulated from an electric circuit connecting the drum-shaped first discharge electrode and the opposing second discharge electrode. In the electric circuit, a conductor connected to the first discharge electrode is inserted into a rotating shaft to which the first discharge electrode is fixed. The first discharge electrode is electrically insulated from at least the penetration portion of the rotating shaft that penetrates the vacuum vessel.

[Function] According to the present invention, since the vacuum container is insulated from the electric circuit, it is possible to prevent loss caused by discharge of plasma into the vacuum container. In addition, since the first discharge electrode is insulated from the outer part including the rotating shaft penetration part, and the vacuum container is insulated from the electric circuit, Since there is no risk of insufficient insulation in narrow corners, there is no risk of abnormal arc discharge occurring here. Furthermore, since a part of the electric circuit is inserted through the rotating shaft that rotates together with the first discharge electrode, even though the first discharge electrode is insulated from the rotating shaft as described above, A slip ring for energizing the rotating first discharge electrode can be provided outside the vacuum vessel. Therefore, there is no risk that the plasma atmosphere will be damaged by the wear powder of the slip ring or that arc discharge will occur in the wear powder.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, inside a vacuum container 1, a drum-shaped drum electrode (first discharge electrode) 2 and a number of rod electrodes (second discharge electrodes) 3 facing this drum electrode 2 are arranged in parallel. It is installed in A voltage is applied between the discharge electrodes 2 and 3 from an AC power source 4 via a transformer 5 and an electric circuit 6 that connects the discharge electrodes 2 and 3.

The vacuum container 1 is made of stainless steel and is filled with extremely low pressure plasma processing gas by a gas container 7 filled with plasma processing gas and a vacuum exhaust device 8 for evacuating the inside of the vacuum container 1. It is kept in the same condition. Reference numerals 9 and 10 designate preliminary vacuum chambers, which are provided with a plurality of seal rolls and a seal chamber in the running direction of the sheet material, and by vacuum suction inside the seal chamber, the pressure is gradually reduced from atmospheric pressure to create a vacuum. It helps maintain a predetermined pressure inside the container 1. A is a sheet-like material, which is guided by a number of guide rolls 12 from an unwinding machine 11, and is rolled by a winding machine 13 along the outer circumferential surface of the drum electrode 2 which is rotationally driven.
is wound up. In other words, the sheet-like material A of the unwinding machine 11 is transferred to the vacuum container 1 held in a plasma atmosphere.
The film is continuously subjected to low-temperature plasma treatment on the drum electrode 2 inside, and is wound up by a winder 13.

In FIG. 2, the drum electrode 2 has a water jacket (cooling passage) 2a through which a cooling medium with low conductivity such as distilled water or silicone oil flows.
is provided. Both side wall portions 2b of this drum electrode 2 are curved inward into a spherical shape, and are fixed to a rotating shaft 17 at the center via insulating members 14, 15 and a joint 16. The insulating member 14
is a circular ring with a U-shaped cross section and is made of, for example, a glass lining with excellent weather resistance. On the other hand, the insulating member 15 has an annular shape and is made of polycarbonate, for example. That is, the drum electrode 2 is electrically insulated from the rotating shaft 17 driven by a motor (not shown).

The rotating shaft 17 is made of stainless steel with low magnetic permeability or high volume resistivity, and a penetrating portion 17 in the rotating shaft 17 that penetrates into the vacuum container 1
a and end portion 17b are pivotally supported by vacuum vessel 1 via bearings 18 and 19, respectively. This rotating shaft 17 is provided with two long holes 17c, and the copper pipes 20,
20 is inserted. This copper tube 20 is provided with an insulating member 26 made of fluororesin on its outer surface, and a cooling medium flows inside the copper tube 20 . In other words, the hollow portion of the copper tube 20 constitutes a cooling passage. This cooling passage is connected in series to the water jacket 2a via a flexible tube 21.

Both ends 3a of the plurality of rod electrodes 3 are fixed to a pair of support members 22. This support member 2
2 is supported by the vacuum container 1 via an insulator 23.

One side of the electric circuit 6 is inserted into the vacuum vessel 1 from the introduction terminal 6a via an insulating flange 24 that insulates the vacuum vessel 1 from the electric circuit 6, and the rod electrode 3
It is connected to the. The other is the slip ring 2
5. It is connected to the drum electrode 2 via the copper tube 20, which is a conductor inserted into the rotating shaft 17, and a conducting wire 27. That is, the vacuum container 1 is electrically insulated from the electric circuit 6 and is maintained in a grounded state. Note that the electric circuit 6 and both discharge electrodes 2 and 3 are kept ungrounded and strictly insulated from the vacuum vessel 1.

In the above configuration, in the present invention, since the vacuum vessel 1 is insulated from the electric circuit 6, there is no possibility that plasma will be discharged from the rod electrode 3 to the vacuum vessel 1, so that power consumption can be prevented.

Further, for example, insulating members 14 and 15 may be interposed between the drum electrode 2 and the rotating shaft 17 to
17 is insulated. That is, the drum electrode 2 is electrically insulated from at least the penetration portion 17a of the rotating shaft 17 that penetrates the vacuum container 1. On the other hand, the vacuum container 1 is insulated from the electric circuit 6. Therefore, the penetrating portion 17a of the rotating shaft 17,
Since there is no risk of insufficient insulation between the adjacent bearing 18 of the vacuum vessel 1, that is, the narrow corner, and there is no risk of abnormal arc discharge occurring on the inner wall of the vacuum vessel, continuous operation is possible. can be achieved.

By the way, in this invention, since the conductor of the electric circuit 6 connected to the drum electrode 2, that is, the copper pipe 20, is inserted through the rotating shaft 17 which rotates together with the drum electrode 2, the rotating shaft 17 and the conductor connected to the drum electrode 2 are inserted. Drum electrode 2
A slip ring 25 can be provided outside the vacuum vessel 1 for energizing the rotating drum electrode 2 even though the drum electrode 2 is insulated from the vacuum vessel 1.
Therefore, there is no risk that the plasma atmosphere will be damaged by the abrasion powder of the slip ring 25 or that arc discharge will occur in the abrasion powder, so that the plasma processing apparatus can be operated smoothly and continuously.

By the way, in order to perform good plasma processing, it is necessary to prevent heat generation in the drum electrode 2 and the copper tube 20 due to large electric power. Here, in this embodiment, a water jacket 2 which is a cooling passage for a cooling medium is used.
a and the copper tube 20 are connected in series. Therefore, there is no need to separately provide piping for cooling the copper tube 20, that is, the portion of the electric circuit 6 that is inserted into the rotating shaft 17. Further, by using the copper tube 20 as a conductive wire, the copper tube 20 that generates heat can be cooled extremely effectively. In addition, the rotating shaft 17
Since it is made of stainless steel with low magnetic permeability or high volume resistivity, there is little risk of heat generation due to electromagnetic permeation of the current flowing inside the copper tube 20.

In this embodiment, two copper tubes 20 are provided for the outward and return paths of the cooling medium, but the number of copper tubes 20 may be three or more or one. When there is only one copper pipe 20, the inside and outside of the copper pipe 20 are
It may be the outward or return path of the cooling passage.

In addition, as shown in FIG. 3, on both sides of the vacuum container 1,
The present invention is also applicable to a case where the unwinding machine 11 and the winding machine 13 are provided in other vacuum vessels 1A and 1B, respectively, and both vacuum vessels 1A and 1B are flanged to the vacuum vessel 1. obtain. Furthermore, although not shown, the unwinding machine 11 and the winding machine 13 may be arranged together with the electrodes 2 and 3 in the vacuum vessel 1.

[Effects of the Invention] As explained above, according to the present invention, it is possible to prevent waste of power in a plasma processing apparatus for sheet-like materials that consumes a large amount of power, and also to prevent abnormal arc discharge. The processing equipment gains industrial processing capacity and becomes capable of continuous operation.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention;
FIG. 2 is a longitudinal sectional view of FIG. 1, and FIG. 3 is a schematic diagram of another plasma processing apparatus for sheet-like materials to which the present invention is applied. DESCRIPTION OF SYMBOLS 1... Vacuum container, 2... First discharge electrode (drum electrode), 2a... Cooling passage (water jacket), 3
... second discharge electrode (rod electrode), 6 ... electric circuit,
17...Rotating shaft, 17a...Penetration part, 20...Conductor (copper tube), A...Sheet-like material.

Claims (1)

[Scope of Claims] 1. A drum-shaped first discharge electrode that is fixed to and rotates on a rotating shaft that penetrates the vacuum container and has a sheet-shaped material along its outer circumferential surface; A plasma processing apparatus for a sheet-like material in which a second discharge electrode is provided inside a vacuum container, wherein the vacuum container is electrically insulated from an electric circuit connecting both of the discharge electrodes, and a second discharge electrode is provided inside the electric circuit. , 1st
Plasma treatment of a sheet-like material in which a conductor connected to a discharge electrode is inserted into the rotating shaft, and the first discharge electrode is electrically insulated from at least a penetration portion of the rotating shaft that penetrates the vacuum container. Device. 2. The first discharge electrode is provided with a cooling passage through which a cooling medium flows, and this cooling passage is connected in series to a cooling passage for a cooling medium that cools the conductor inserted into the rotating shaft. A plasma processing apparatus for sheet-like materials according to claim 1, characterized in that: