Plasma treatment system and plasma treatment method

Abstract

This plasma treatment system and method can be widely applied to any type or shape of object being treated with plasma, and eliminates the problems of cutting and attaching indicators during plasma treatment, as well as the problems of disposing of release paper and used indicators, while also providing flexibility to handle various plasma intensities. [Solution] A plasma processing system that irradiates an object to be processed with plasma, (1) A direct-liquid marker, which is a device loaded with plasma indicator ink, that applies an ink coating film whose optical properties change due to plasma irradiation to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece, inside a plasma irradiation device, (2) A plasma irradiation device that irradiates the object to be processed and the surrounding members with plasma, (3) A measuring device for measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal device for removing the plasma-irradiated ink coating, A plasma processing system characterized by comprising the following features.

Description

Technical Field

[0001] The present invention relates to a plasma processing system and a plasma processing method. In this specification, plasma processing means plasma processing using plasma generated by applying an alternating voltage, a pulse voltage, a high frequency, a microwave, etc. using a plasma generating gas, and both reduced-pressure plasma and atmospheric-pressure plasma are applicable.

Background Art

[0002] Conventionally, plasma processing has been used as one of the means for sterilizing various equipment and instruments in hospitals, research institutions, etc. Also, in a wide range of fields including plasma dry etching in the manufacture of semiconductor elements, plasma processing is used for surface modification or cleaning of workpieces such as films, electronic components, optical components, medical and biological equipment, and mechanical parts.

[0003] In recent years, atmospheric-pressure plasma has been particularly applied in applications for activating the surfaces of various workpieces and improving coating performance and adhesion. For example, processes for treating the surfaces of optical films, terminals of display panels, mating surfaces of parts of automotive engines with complex structures, bonding pads of semiconductor components, and microelectronic components with atmospheric-pressure plasma have been adopted. Also, for the purpose of improving the hydrophilicity and adhesiveness of catheters used in the medical and biological fields, improving the culturing properties of cell culture media, and improving the hydrophilicity of the inner surface of infusion tubes, etc., treatment with atmospheric-pressure plasma has been adopted. Thus, the types and shapes of workpieces to be subjected to plasma processing have become very diverse compared to the past.

[0004] On the other hand, since plasma cannot be seen with the naked eye, it is not possible to accurately determine whether or not plasma treatment has been properly applied to a workpiece by simply observing its appearance. Therefore, various types of indicators with shapes whose optical properties change upon plasma irradiation are used. Plasma indicators are used not only to confirm the effect of plasma treatment, but also to confirm whether the workpiece is uniformly irradiated with plasma (confirmation of in-plane distribution) and whether there is any variation in the performance of multiple plasma irradiation devices (confirmation of performance differences between devices). The surface of the plasma indicator changes color (including decolorization) due to plasma treatment (contact with active species such as radicals and ions), so the effect and uniformity of the plasma treatment can be judged by visual inspection or measurement with a colorimeter of the degree of discoloration.

[0005] Commercially available plasma indicators include, for example, label-type or card-type (sheet-type) indicators of various sizes, printed on clean paper with ink that changes optical properties upon plasma irradiation, and dummy wafer-type indicators used in semiconductor device manufacturing, where a wafer-shaped substrate is printed with ink that changes optical properties upon plasma irradiation (see Figure 6). These indicators are sensitively adjusted to suit various plasma treatment intensities by changing the type or density of the ink, the thickness of the print, etc. In other words, it is necessary to select an indicator with sensitivity (color change performance) that matches the plasma intensity.

[0006] Furthermore, as an invention of a plasma irradiation system equipped with a feeder that supplies such an indicator (a substrate whose optical properties change upon plasma irradiation), Patent Document 1 describes: "A plasma irradiation system that irradiates an object to be treated with plasma, The aforementioned plasma irradiation system A feeder that supplies a substrate whose optical properties are altered by plasma irradiation, A dispensing device for applying the substrate supplied by the feeder to an object to be processed, A plasma irradiation device that irradiates the substrate applied to the object to be treated with plasma, A plasma irradiation system characterized by comprising a measuring device for measuring the optical properties of the substrate irradiated with plasma by the aforementioned plasma irradiation device. The invention is disclosed.

[0007] Furthermore, Patent Document 2 describes an invention of an information processing device used for predicting the degree of success of sterilization treatment using plasma, An information processing device for processing using an indicator having a color-changing region, The discolored region changes color according to the degree to which the process is achieved. The aforementioned information processing device is A receiving means for receiving input values ​​for multiple parameters used in the aforementioned process, A prediction means for predicting the degree of completion of the process obtained from the values ​​of the plurality of parameters input to the reception means, An information processing device characterized by having the following features. The invention is disclosed. In the text of Patent Document 2, a test paper having a color-changing region, a so-called chemical indicator (CI), is used as an indicator whose color changes according to the degree of plasma treatment (paragraphs

[0012] to

[0015] ). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2021-177486 [Patent Document 2] Japanese Patent Publication No. 2023-020594 [Overview of the project] [Problems that the invention aims to solve]

[0009] As mentioned above, the types and shapes of objects subjected to plasma treatment have become much more diverse than before. Therefore, depending on the shape or size of the object to be treated, it may be difficult to attach card-type indicators with tape, or it may be necessary to cut the indicators to a smaller size to match the shape of the object to be treated, or conversely, to attach multiple indicators side by side if the object to be treated is large. Furthermore, when using card-type indicators, in addition to the work of attaching them with tape, it is necessary to peel them off and discard them after plasma treatment. Moreover, although label-type indicators can be attached as is, the release paper becomes waste, and the work is not easy when attaching them to objects with complex shapes, and the label has to be cut to the appropriate size.

[0010] Therefore, the present invention aims to provide a plasma treatment system and plasma treatment method that can be widely applied regardless of the type and shape of the object to be treated with plasma, and that can solve the problems of cutting and attaching indicators during plasma treatment, the problems of disposing of release paper and used indicators, and that can flexibly respond to various plasma intensities. [Means for solving the problem]

[0011] The inventors conducted extensive research to achieve the above objectives and, as a result, discovered that these objectives can be achieved by a plasma processing system equipped with a specific device, thus completing the present invention.

[0012] In other words, the present invention relates to the following plasma processing system and plasma processing method. 1. A plasma treatment system that irradiates an object to be treated with plasma, (1) A direct-liquid marker, which is a device loaded with plasma indicator ink, that applies an ink coating film whose optical properties change due to plasma irradiation to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece, inside a plasma irradiation device, (2) A plasma irradiation device that irradiates the object to be processed and the surrounding members with plasma, (3) A measuring device for measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal device for removing the plasma-irradiated ink coating, A plasma processing system characterized by comprising the following features. 2. The plasma processing system according to item 1, wherein the direct-liquid marker comprises an ink reservoir and a writing section, with a valve interposed between them and connected to the writing section, the writing section being supported from the axial center to the rear end of the writing section by a cylindrical ink absorber installed in the tip stopper, a valve body connected to the rear end of the writing section, the valve having a valve body and a valve chamber, the valve chamber having an opening on the reservoir side communicating with the ink reservoir and an opening on the writing section side communicating with the writing section, and the valve body being disposed therein, the valve body normally closing the opening on the writing section side while the opening on the reservoir side is open, and the valve body moves and the opening on the writing section side is opened when the writing section is pressed. 3. The plasma treatment system according to item 1 or 2 above, wherein the plasma irradiation device is a reduced-pressure plasma irradiation device or an atmospheric pressure plasma irradiation device. 4. The plasma treatment system according to any one of items 1 to 3 above, wherein the peripheral members are at least one selected from the group consisting of a carrier, tray, table, board, magazine, cassette, packaging (pouch) containing the workpiece, which is located inside the plasma irradiation device and holds the workpiece; a dummy workpiece having the same shape as the workpiece; a transfer device that lifts and / or moves the workpiece; and a conveyor that transports the workpiece. 5. The plasma treatment system according to any one of items 1 to 4 above, wherein the measuring device is a colorimeter for measuring the color difference of the ink coating film before and after plasma irradiation, or a transmission spectrometer for measuring the transmittance difference of the ink coating film before and after plasma irradiation. 6. The removal device is a plasma treatment system according to any one of items 1 to 5 above, which dissolves and removes the plasma-irradiated ink coating using a solvent. 7. A plasma treatment method in which plasma is irradiated onto an object to be treated, (1) An application step of applying an ink coating film of a plasma indicator ink whose optical properties change by plasma irradiation to the object to be processed and / or a peripheral member that is plasma-irradiated together with the object to be processed inside the plasma irradiation device, wherein the application step is an application step using a direct liquid marker which is an application device loaded with plasma indicator ink, (2) A plasma irradiation step of irradiating the object to be processed and the peripheral member with plasma, (3) A measurement step of measuring the optical properties of the ink coating film irradiated with plasma, (4) A removal step of removing the ink coating film irradiated with plasma, A plasma processing method characterized by comprising the above. 8. The direct liquid marker includes an ink reservoir and a writing part, and a valve connected to the writing part is interposed between the two. The writing part is supported by a cylindrical ink absorber installed inside the tip plug from the central part to the rear end in the axial direction of the writing part. A valve body is connected to the rear end of the writing part. The valve has a valve body and a valve chamber. The valve chamber is provided with a reservoir-side opening communicating with the ink reservoir and a writing part-side opening communicating with the writing part, and the valve body is arranged. Normally, the valve body closes the writing part-side opening, while the reservoir-side opening is open. By pressing the writing part, the valve body moves and the writing part-side opening is opened. The plasma processing method according to item 7 above.

[0013] As a related invention in which a part of the configuration of the present invention is changed, the following inventions of a plasma processing system and a plasma processing method can be disclosed. A. A plasma processing system for irradiating an object to be processed with plasma, and (1) Inside the plasma irradiation device, a dispenser, an inkjet printing device, or a pad printing device which is an application device loaded with plasma indicator ink for applying an ink coating film whose optical properties change by plasma irradiation to the object to be processed and / or a peripheral member that is plasma-irradiated together with the object to be processed, (2) The plasma irradiation device for irradiating the object to be processed and the peripheral member with plasma, (3) A measuring device for measuring the optical properties of the plasma-irradiated ink coating film; (4) A removing device for removing the plasma-irradiated ink coating film; A plasma processing system, characterized by comprising the above. B. A plasma processing method for irradiating a workpiece with plasma, comprising: (1) An application step of applying an ink coating film of a plasma indicator ink whose optical properties change by plasma irradiation to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece inside a plasma irradiation device. The application step is an application step using a dispenser (discharge device), an inkjet printing device, or a pad printing device that is an application device loaded with the plasma indicator ink; (2) A plasma irradiation step of irradiating the workpiece and the peripheral member with plasma; (3) A measurement step of measuring the optical properties of the plasma-irradiated ink coating film; (4) A removal step of removing the plasma-irradiated ink coating film; A plasma processing method, characterized by comprising the above.

[0014] In the above related invention, as the dispenser (discharge device), inkjet printing device, or pad printing device as the application device of the plasma indicator ink, known devices and apparatuses can be widely applied. In addition, the description of each component other than the application device is incorporated by reference to the description in this specification regarding the plasma processing system and plasma processing method of the present invention. [Advantages of the Invention]

[0015] According to the plasma processing system of the present invention, an ink coating is applied to the workpiece and / or surrounding components that are plasma-irradiated together with the workpiece using a direct-ink marker, which is an application device loaded with plasma indicator ink. Therefore, it can be widely applied regardless of the type and shape of the workpiece to be plasma-treated, and the problems of cutting and attaching indicators during plasma processing, as well as the disposal of release paper and used indicators, are eliminated. Furthermore, by changing the writing part (tip) of the direct-ink marker (replacing it with a tip with a different outer diameter or tip shape, a tip with different porosity, or a tip with a groove on the tip support part that adjusts the ink flow rate) and / or adjusting the number of times the same tip is applied, it is possible to flexibly respond to various plasma intensities. Moreover, since the ink coating is formed by a direct-ink marker, the ink coating can be easily removed with a removal device after plasma processing, substantially eliminating waste such as substrates (clean paper, etc.), release paper, and adhesive tape that are used in conventional plasma indicators, and eliminating the need for recycling processes for substrates such as dummy wafers. [Brief explanation of the drawing]

[0016] [Figure 1] This is a schematic cross-sectional view showing an example of a direct-liquid marker used in the present invention. [Figure 2] This is a cross-sectional view of the tip of an example of a direct-ink type marker used in the present invention (however, in a configuration in which ink is not supplied to the writing section). [Figure 3] Figure 2 is an enlarged cross-sectional view of the valve chamber of the direct-liquid marker shown. [Figure 4] This is a cross-sectional view of the tip of an example of a direct-ink type marker used in the present invention (however, in a configuration in which ink is supplied to the writing part). [Figure 5] Figure 4 is an enlarged cross-sectional view of the valve chamber of the direct-liquid marker shown. [Figure 6]This figure shows examples of various conventionally known plasma indicators. Specifically, examples include label-type or card-type (sheet-type) indicators with plasma indicator ink printed on clean paper, chemical indicators (CIs), and dummy wafer-type indicators with plasma indicator ink printed on wafer-shaped substrates used in the manufacture of semiconductor devices. [Figure 7] This figure shows an example of plasma treatment being performed on substrates intended for various objects to be treated and / or surrounding components by forming an ink coating using a direct-liquid marker filled with plasma indicator ink containing an organic solvent, followed by writing (filling) the coating. The substrates are transparent PET (Toray Industries' "Lumirror Film T60"), white foamed PET (Toyobo's "Crisper K2323"), copper (the copper foil side of Taiyo Technorex's "Flexible Copper-Clad Laminate (Laminate of Copper Foil and Polyimide Insulating Film)"), polyimide (the polyimide insulating film side of Taiyo Technorex's "Flexible Copper-Clad Laminate (Laminate of Copper Foil and Polyimide Insulating Film)"), and glass epoxy substrate (Taiyo Technorex's "FR-4 Substrate"). [Figure 8] This diagram exemplifies the relationship between differences in film thickness due to the number of coats applied, differences in plasma treatment time, and differences in discoloration when an ink coating film is formed by writing (filling) with a direct-liquid marker filled with plasma indicator ink containing an organic solvent. [Figure 9] This diagram exemplifies how even with the same plasma intensity, differences in ink film thickness (amount applied) can lead to differences in the discoloration properties of the ink coating. [Figure 10] This figure shows an example of discoloration when a portion of a substrate (the white PET mentioned above), representing the object to be treated and / or surrounding components, is plasma-treated after drawing multiple parallel lines at intervals using a direct-liquid marker filled with plasma indicator ink containing an organic solvent. For comparison, an example using a conventional sheet-type plasma indicator is also shown. [Figure 11]This figure shows an example of the discoloration of a coating film when plasma-treated with a direct-liquid marker filled with plasma indicator ink containing an organic solvent, applied to a substrate (a φ4mm PP pipe as a thin workpiece, and a 20ml glass volumetric flask as a curved workpiece) that is intended for a workpiece and / or surrounding component to which conventional label-type or card-type (sheet-type) indicators and chemical indicators (CIs) cannot be applied or are difficult to apply. [Figure 12] This figure shows an example of a block diagram of the plasma processing system of the present invention. [Figure 13] This is a block diagram illustrating variations in the apparatus constituting the plasma processing system of the present invention. (a) is a diagram showing the minimum apparatus necessary to perform the substantial steps of the plasma processing system of the present invention. (b) is a diagram showing an embodiment in which a preliminary measuring device for measuring the optical properties of the ink coating film before plasma processing is provided between the application device and the plasma irradiation device (meaning "between steps," and the same applies hereinafter). (c) is a diagram showing an embodiment in which an accelerated drying device and a cooling device are provided between the application device and the plasma irradiation device to accelerate the drying and stabilize the ink coating film formed by the application device at an early stage. [Modes for carrying out the invention]

[0017] The plasma processing system and plasma processing method of the present invention will be described in detail below.

[0018] The plasma processing system of the present invention is A plasma treatment system that irradiates an object to be treated with plasma, (1) A direct-liquid marker, which is a device loaded with plasma indicator ink, that applies an ink coating film whose optical properties change due to plasma irradiation to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece, inside a plasma irradiation device, (2) A plasma irradiation device that irradiates the object to be processed and the surrounding members with plasma, (3) A measuring device for measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal device for removing the plasma-irradiated ink coating, It is characterized by having the following features.

[0019] In the plasma processing system, the direct liquid marker application device, plasma irradiation device, measuring device, and removal device are each controlled by a control device (controller). An example of a block diagram of the plasma processing system of the present invention is shown in Figure 12. To illustrate using Figure 12, in the plasma processing system of the present invention, the application device, plasma processing device, measuring device, and removal device are each controlled by a control device. An input device that gives instructions to the control device and an output device that outputs the results of control by the control device are also provided. In addition, a drive device that serves as a power source to drive the entire system is provided. The devices shown in Figure 12 can be said to be the minimum configuration that constitutes the plasma processing system of the present invention, but it goes without saying that in addition to the above-mentioned devices, an identification device that identifies the object to be processed, a transfer device or transport device (transport robot, conveyor, etc.) that moves and / or transports the object to be processed, a storage device that stores measurement results in conjunction with the measuring device, a judgment device that determines the suitability of plasma processing based on the measurement results, and other related devices may be further provided.

[0020] According to the plasma processing system of the present invention, an ink coating is applied to the workpiece and / or surrounding components that are plasma-irradiated together with the workpiece using a direct-ink marker, which is an application device loaded with plasma indicator ink. Therefore, it can be widely applied regardless of the type and shape of the workpiece to be plasma-treated, and the problems of cutting and attaching indicators during plasma processing, as well as the disposal of release paper and used indicators, are eliminated. Furthermore, by changing the writing part (tip) of the direct-ink marker (replacing it with a tip with a different outer diameter or tip shape, a tip with different porosity, or a tip with a groove on the tip support part that adjusts the ink flow rate) and / or adjusting the number of times the same tip is applied, it is possible to flexibly respond to various plasma intensities. Moreover, since the ink coating is formed by a direct-ink marker, the ink coating can be easily removed with a removal device after plasma processing, substantially eliminating waste such as substrates (clean paper, etc.), release paper, and adhesive tape that are used in conventional plasma indicators, and eliminating the need for recycling processes for substrates such as dummy wafers.

[0021] (Plasma irradiation device) The plasma irradiation device in the plasma processing system of the present invention includes a direct-liquid marker, which is a device loaded with plasma indicator ink, that applies an ink coating film whose optical properties change upon plasma irradiation to at least the workpiece and / or peripheral members that are plasma-irradiated together with the workpiece. The device has the function of applying the ink coating film to the workpiece and / or peripheral members using the direct-liquid marker, and further irradiating the workpiece and peripheral members with plasma. Such a plasma irradiation device may be either a reduced-pressure plasma treatment or an atmospheric-pressure plasma treatment. The term "inside the plasma irradiation device" means "inside the plasma irradiation device or plasma irradiation facility in a broad sense, including peripheral devices," and does not necessarily mean that the device having the plasma irradiation function and the application device are integrated as a single device. Therefore, the plasma processing system of the present invention includes embodiments in which the device having the plasma irradiation function and the application device are separately provided inside the plasma irradiation device or plasma irradiation facility in a broad sense, including peripheral devices.

[0022] Specific examples of reduced-pressure plasma treatment include, for example, applications such as film formation, ashing, cleaning, and surface modification of flat panel displays (such as liquid crystal displays); applications such as film formation, ashing, cleaning, and surface modification in semiconductor manufacturing processes; applications such as cleaning and surface modification of mounted substrates or printed circuit boards; sterilization applications for medical devices, etc.; and applications such as cleaning and surface modification of mounted components.

[0023] Furthermore, specific examples of atmospheric pressure plasma treatment include, for example, applications such as cleaning and surface modification of flat panel displays (such as liquid crystal displays); cleaning and surface modification of mounted substrates or printed circuit boards; surface modification of automobile and aircraft parts; and surface modification, disinfection, sterilization, and treatment in the medical field (dentistry or surgery).

[0024] The gas used for generating reduced-pressure plasma is not limited to any gas that can generate plasma by applying AC voltage, pulse voltage, high frequency, microwave, etc., under reduced pressure. Examples include oxygen, nitrogen, hydrogen, chlorine, hydrogen peroxide, helium, argon, silane, ammonia, sulfur bromide, water vapor, nitrous oxide, tetraethoxylan, carbon tetrafluoride, trifluoromethane, carbon tetrachloride, silicon tetrachloride, sulfur hexafluoride, titanium tetrachloride, dichlorosilane, trimethylgallium, trimethylindium, and trimethylaluminum. These reduced-pressure plasma generating gases can be used individually or in mixtures of two or more.

[0025] The atmospheric pressure plasma generating gas is not limited to any gas that can generate plasma by applying an AC voltage, pulse voltage, high frequency, microwave, etc., under atmospheric pressure. Examples include oxygen, nitrogen, hydrogen, argon, helium, and air. These atmospheric pressure plasma generating gases can be used individually or in mixtures of two or more.

[0026] (The object to be processed and its surrounding components) Examples of objects to be treated include those in the various fields mentioned above that can be subjected to plasma treatment, such as medical equipment and instruments that are subject to sterilization; and a wide range of objects that are subject to surface modification, adhesion improvement, coating improvement, cleaning, etc., such as films, electronic components, optical components, medical and bio-related equipment, and mechanical parts. More specifically, examples include the surface of optical films, terminals of display panels, mating surfaces of parts of complex automobile engines, bonding pads of semiconductor components, surfaces of micro-electronic components, the surface of catheters used in the medical and bio-fields, cell culture media, and the inner surface of intravenous infusion tubes.

[0027] Peripheral components include at least one selected from the group consisting of carriers, trays, tables, boards, magazines, cassettes, packaging (pouches) containing the workpiece, dummy workpieces identical in shape to the workpiece, transfer devices for lifting and / or moving the workpiece, and conveyors for transporting the workpiece. Thus, peripheral components broadly include the surrounding area and peripheral components that are plasma-irradiated together with the workpiece.

[0028] (Direct-type marker) In the plasma processing system of the present invention, the direct-liquid marker is a device that applies an ink coating film whose optical properties change due to plasma irradiation to the workpiece and / or surrounding members that are plasma-irradiated together with the workpiece, inside the plasma irradiation device.

[0029] A direct-ink marker is not particularly limited as long as it comprises an ink reservoir and a writing section (a tip, which is the pen tip), as shown in Figure 1, for example, and when the writing section is pressed, a valve opens, supplying ink from the ink reservoir to the writing section, and allowing an ink coating to be applied to the object to be processed and / or surrounding members at the tip of the writing section. In Figure 1, a stirring ball (steel ball) is also built into the ink reservoir for stirring the ink. In the present invention, the direct-ink marker is the application device, but the application device may have peripheral equipment that drives the direct-ink marker and applies an ink coating to a desired position on the object to be processed and / or surrounding members by writing. For example, it is preferable to fix the direct-ink marker to the tip of a robot arm and form an ink coating on a desired part of the object to be processed and / or surrounding members by writing based on input information. Conventional known devices or methods can be used as a marking system to realize such a configuration. Furthermore, if the ink coating is formed in a linear or ruled line pattern on the flat portion of the object to be processed and / or surrounding members, a marking system incorporating the technology disclosed in, for example, a ruled line forming device for blackboards (Japanese Patent Publication No. 2021-14090) can also be used.

[0030] As an example of such a direct-ink marker, a suitable direct-ink marker is one that comprises an ink reservoir and a writing section, with a valve interposed between them and connected to the writing section, the writing section being supported from the axial center to the rear end by a cylindrical ink absorber installed in the tip stopper, a valve body connected to the rear end of the writing section, the valve having a valve body and a valve chamber, the valve chamber having an opening on the reservoir side communicating with the ink reservoir and an opening on the writing section side communicating with the writing section, and the valve body being positioned therein, the valve body normally closing the opening on the writing section side while keeping the reservoir side open, and the valve body moving and opening the opening on the writing section side when the writing section is pressed.

[0031] A specific example of a direct-ink marker is described in the embodiments illustrated in Figures 2-5. In Figures 2-5, the direct-ink marker 1 mainly consists of a container 2, a tip 3, a writing part (tip) 4, a valve 5, and a cap 6. The configuration of each component will be described below.

[0032] Container 2 functions as an ink reservoir (liquid reservoir) and has a cylindrical shape with one end open and the other end closed. In this embodiment, the container 2 is made with a slightly smaller diameter on the open side, and a screw is provided in that part. Container 2 is formed by deep drawing, extrusion molding, ironing, etc., using aluminum, stainless steel, steel, etc. as materials, or by injection molding, blow molding, etc., using synthetic resin as materials, or by glass blow molding, etc.

[0033] The tip stopper 3 is made by injection molding of synthetic resin, and its outer shape tapers in three stages, with the inside communicating in the longitudinal direction. The internal communication hole 10 is provided coaxially with the container 2. A screw is also provided inside the thicker side of the tip stopper 3. This screw is combined with a screw provided on the container 2 to form a single unit. The communication hole 10 is provided with multiple protrusions (not shown) to align the center of the writing section 4 with the center of the valve body 15 (described later) and to ensure a ventilation hole between the tip stopper 3 and the writing section 4.

[0034] The writing section (tip) 4 has a circular cross-section and consists of a tip with a convex spherical surface at its end. One type of tip is a fiber bundle tip that allows ink to seep out from the tip by capillary action. This tip is made of 5-30 denier polyester or the like, and its strength is improved by impregnating the surface layer of the fiber bundle of the tip with resin, thereby hardening it and forming a resin-impregnated layer.

[0035] Valve 5 is housed in the container 2 and the stopper 3 and consists of an outer casing member 11, an inner casing member 12, a valve body 15, and a spring 18. Specifically, the outer casing member 11 has a cylindrical shape overall, with a flange 20 at its tip. The outer diameter of the part of the flange 20 closest to the flange is equal to the inner diameter of the opening of the container 2, while other parts are made slightly narrower. The outer casing member 11 is in communication in the longitudinal direction. That is, the large diameter side of the outer casing member 11 is open. An ink reservoir side opening 21 is provided on the small diameter side of the outer casing member 11. The inner diameter of the outer casing member 11 is smaller near the reservoir side opening, but is uniform in other parts.

[0036] The interior component 12 is composed of a flange 22 and a cylindrical portion 23. The outer diameter of the flange 22 is equal to the outer diameter of the open side of the exterior component 11, and the outer diameter of the cylindrical portion 23 is equal to the inner diameter of the open side of the exterior component 11. The length of the cylindrical portion 23 is from the open side of the exterior component 11 to approximately the midpoint in the longitudinal direction of the exterior component 11.

[0037] A bulge 13 is formed around the entire inner surface of the end of the interior member 12 on the side with the reservoir opening, not the flange side.

[0038] The valve body 15 is rod-shaped, thickening near the center to form a conical portion 24, and behind the conical portion 24, a nearly uniform rod-shaped portion 17 continues. The rear end of the rod-shaped portion 17 is pointed. On the front side, that is, the side of the writing portion 4, a cylindrical portion 16 is formed so that the reduced diameter portion 14 at the rear end of the writing portion 4 can be inserted and fixed.

[0039] In the direct-ink marker 1 of this embodiment, the seal portion of the writing section opening 26 can be sealed by the close contact between the conical portion 24 and the bulging portion 13 of the valve body 15.

[0040] Next, the assembly structure of valve 5 will be described. Valve 5 is made up of an interior member 12 inserted inside an exterior member 11. The valve body 15 is located inside the exterior member 11 and the interior member 12, with its rear end from the conical portion 24 inside the exterior member 11 and its front end further inside the interior member 12. In other words, in the direct liquid type marker 1 of this embodiment, the valve closes when the conical portion 24 of the valve body 15 and the bulging portion 13 at the rear end of the interior member 12 are in close contact inside the exterior member 11.

[0041] The spring 18 is mounted on the valve body 15 and constantly presses the conical portion 24 of the valve body 15 toward the writing portion 4. Under normal conditions, the conical portion 24 is pressed toward the writing portion 4 by the spring 18, causing the conical portion 24 and the bulge 13 to be in close contact and the valve 5 to be closed. As a result, the ink in the valve chamber 25 does not flow toward the writing portion 4.

[0042] The overall assembly structure of the direct-liquid marker 1 of this embodiment is as follows: The valve 5 is inserted into the container 2 from the open end, and the flange 20 abuts against the end face of the container. A stopper 3 is attached to the open end of the container 2. The writing part 4 is slidably inserted into the communication hole 10 of the stopper 3, with its tip protruding out of the stopper 3, and its reduced diameter portion 14 at the rear end inserted into the cylindrical portion 16 of the valve body 15.

[0043] Furthermore, an ink absorber 27 made of a porous material such as sponge is provided inside the tip stopper 3. The ink absorber 27 is formed in a cylindrical shape and is located inside the tip stopper 3, in contact with the writing portion 4 side of the flange of the interior member 12. The writing portion 4 is slidably inserted into the cylinder of the ink absorber 27.

[0044] Furthermore, the container 2 may contain ink and also include a stirring ball (steel ball).

[0045] The writing section 4, whose outer circumference is coated with resin, is provided with a sliding section 28 that slides against the ink absorber 27. As shown in Figure 5, the sliding section 28 on the writing section 4 extends over a range of 10 to 50% of the length of the writing section 4. By grinding the writing section 4 to a depth of 3 to 30% of its diameter, the resin-impregnated layer is removed, exposing the unimpregnated fiber bundles inside. Here, if a recessed section with a depth of 3 to 30% of the writing section 4 is provided, and the fiber bundles are exposed in the recess, the fluidity of the ink can be further improved. Here, the recessed section is provided in any shape, such as a groove or grid, in the longitudinal or circumferential direction of the writing section 4. Furthermore, the rear end of the writing section 4 is reduced in diameter 14 by grinding away 3 to 30% of its diameter over a range of 10 to 60% of its length, so that its diameter becomes 70 to 97% of its original diameter.

[0046] Next, the operation of the direct-ink marker 1 of this embodiment will be described. The normal state of the direct-ink marker 1 of this embodiment, that is, when not writing, is shown in Figures 2 and 3, where the conical portion 24 of the valve body 15 is pressed by the spring 18 and the conical portion 24 is in contact with the bulging portion 13 of the interior member 12. Therefore, the writing-side opening 26 of the valve chamber 25 is closed at all times. As a result, ink does not flow to the writing side.

[0047] On the other hand, at this time, the reservoir-side opening 21 of the valve chamber 25, which is the rear end of the valve body 15, is open. As a result, the ink reservoir 2 and the valve chamber 25 can flow through each other, and the ink in the ink reservoir 2 can flow into the valve chamber 25.

[0048] When the writing section 4 is pressed during use and slid against the ink absorber 27, the valve body 15 is moved backward, and as shown in Figures 4 and 5, the tight seal between the conical section 24 and the bulging section 13 of the interior member 12 is released. As a result, a space is formed between the conical section 24 and the bulging section 13, and the opening 26 on the writing section side is opened. Therefore, the ink that had accumulated in the valve chamber 25 flows out through the fully opened opening 26 on the writing section side, permeates the ink absorber 27, impregnates the writing section, and permeates the entire writing section. The path of ink flow is shown by line A in Figure 5. In the embodiments described above, a valve was shown in which a conical portion 24 is in contact with a bulging portion 13 to close the writing portion side opening 26. However, it is also possible to use a valve with a different structure.

[0049] In the plasma treatment system of the present invention, by employing a direct-ink marker as the application device, an ink coating can be easily formed by writing on fine parts and curved surfaces that cannot be attached or are difficult to attach with label-type or card-type (sheet-type) indicators, chemical indicators (CI), etc., and the effect and uniformity of plasma treatment on the desired area can be confirmed (see Figure 11). Furthermore, as will be described in detail later, the ink coating after plasma treatment can be easily removed by a removal device (particularly a device that dissolves and removes the ink coating using a solvent), so that waste such as substrates (clean paper, etc.), release paper, and adhesive tape is not substantially generated as with conventional plasma indicators, and a process for recycling substrates such as dummy wafers is not required.

[0050] The plasma processing system of the present invention can flexibly respond to various plasma intensities by replacing the writing part (tip) of a direct-ink marker (replacing it with a tip with a different outer diameter or tip shape, a tip with different porosity, or a tip with unevenness added to the tip support part to adjust the ink flow rate) and / or adjusting the number of times the same tip is used for over-inking. As for the type of tip, a tip made of a fiber bundle that causes ink to seep out from the tip by capillary action is common, and by using tips with different porosity of fiber bundle tips, the rate at which ink seeps out from the tip by capillary action can be adjusted.

[0051] (Plasma indicator ink) A plasma indicator ink can be any ink composition whose optical properties change upon plasma irradiation. For example, an ink composition containing a color-changing dye that changes from colored to colorless due to a structural change (partial decomposition, bond cleavage, etc.) caused by the action of plasma (especially the action of active species such as radicals and ions). Various organic and inorganic materials are known as such color-changing dyes, but the following organic dyes are generally known.

[0052] organic dye The organic dyes are not limited to those exhibiting the above behavior, but can be appropriately selected from, for example, direct dyes, acid dyes, basic dyes, mordant dyes, vat dyes, disperse dyes, reactive dyes, and fluorescent whitening dyes. Specifically, the organic dyes include nitroso dyes (10000-10299), nitro dyes (10300-10999), monoazo dyes (11000-19999), diazo dyes (20000-29999), triazo dyes (30000-34999), polyazo dyes (35000-36999), azoic dyes (diazo component) (37000-37275), and azoic dyes (coupling component) (37500-37625), stilbene dyes (40000-40799), carotenoid dyes (40800-40999), diarylmethane dyes (41000-41999), triarylmethane dyes (42000-44999), xanthene dyes (45000-45999), acridine dyes (46000-46999), quinoline dyes (47000-47999), methine dyes (48000-48 999), thiazole dyes (49000-49399), indamine dyes (49400-49699), indophenol dyes (49700-49999), azine dyes (50000-50999), oxazine dyes (51000-51999), thiazine dyes (52000-52999), sulfur dyes (53000-53999), lactone dyes (54000-54999), hydroxyketone dyes (5500 At least one selected from the group consisting of (0-55999), aminoketone dyes (56000-56999), anthraquinone dyes (58000-72999), indigoid dyes (73000-73999), phthalocyanine dyes (74000-74999), natural dyes (75000-75999), and oxidation dyes (76000-76999) is mentioned (the numbers in parentheses are the color index (CI) numbers). Among the above organic dyes, at least one of the anthraquinone dyes and triarylmethane dyes described below is preferred.

[0053] Anthraquinone dyes are not limited to those with anthraquinone as their basic structure, and anthraquinone disperse dyes and the like can also be used. Anthraquinone dyes having amino groups are particularly preferred. More preferably, the anthraquinone dye has at least one amino group, a primary amino group and a secondary amino group. In this case, there may be two or more amino groups, and these may be the same or different from each other.

[0054] Specifically, examples include 1,4-diaminoanthraquinone (CIDisperse Violet 1), 1-amino-4-hydroxy-2-methylaminoanthraquinone (CIDisperse Red 4), 1-amino-4-methylaminoanthraquinone (CIDisperse Violet 4), 1,4-diamino-2-methoxyanthraquinone (CIDisperse Red 11), 1-amino-2-methylanthraquinone (CIDisperse Orange 11), 1-amino-4-hydroxyanthraquinone (CIDisperse Red 15), 1,4,5,8-tetraaminoanthraquinone (CIDisperse Blue 1), and 1,4-diamino-5-nitroanthraquinone (CIDisperse Violet 8) (the names in parentheses are the color index names).

[0055] Other dyes known as CISolvent Blue 14, CISolvent Blue 35, CISolvent Blue 58, CISolvent Blue 63, CISolvent Violet 13, CISolvent Violet 14, CISolvent Red 52, CISolvent Red 114, CIVat Blue 21, CIVat Blue 30, CIVat Violet 15, CIVat Violet 17, CIVat Red 19, CIVat Red 28, CIAcid Blue 23, CIAcid Blue 80, CIAcid Violet 43, CIAcid Violet 48, CIAcid Red 81, CIAcid Red 83, CIReactive Blue 4, CIReactive Blue 19, CIDisperse Blue 7, etc., can also be used. Among these anthraquinone dyes, CISolvent Blue 58, CI Disperse Blue 7, and CI Disperse Violet 1 are preferred.

[0056] Triarylmethane-based dyes are not limited to those containing a triarylmethane structure. Examples include CIAcid Blue 90, CIAcid Green 16, CIAcid Violet 49, CIBasic Red 9, CIBasic Blue 7, CIAcid Violet 1, CIDirect Blue 41, CIMordnt Blue 1, and CIMordnt Violet 1.

[0057] These organic dyes can be used individually or in mixtures of two or more, and by changing the type of dye or the combination of mixtures, the color (type and intensity of color) and detection sensitivity in the discoloration state can be arbitrarily adjusted.

[0058] The amount of organic dye can be appropriately determined depending on the type of organic dye and the desired hue, but generally, it is desirable to have about 0.05 to 20% by weight, and particularly 0.1 to 10% by weight, in the ink composition. If the amount of organic dye exceeds 20% by weight, the solubility or dispersibility in the solvent may decrease during the preparation of the ink composition, or it may become difficult to form a uniform ink film. In addition, the color of the ink film (the color before discoloration) may become too dark. On the other hand, if the amount of organic dye is less than 0.05% by weight, the color of the ink film (the color before discoloration) may become too light, and in particular, the hue change accompanying the change in thickness of the ink film may be small, and the gradation may decrease. In both cases of excessive and insufficient organic dye content, it may become difficult to visually confirm the color change before and after discoloration.

[0059] In this invention, dyes or pigments other than the above-mentioned organic dyes may be included. For example, dyes that do not discolor or are difficult to discolor in a plasma treatment atmosphere may be included. Examples of such dyes that do not discolor or are difficult to discolor include organic pigments and titanium dioxide. This enhances the change in color tone when the organic dye discolors, thereby further improving the visibility of the discoloration. Furthermore, by including dyes that do not discolor or are difficult to discolor, such as titanium dioxide, the substrate-concealing effect of the ink coating is improved, thereby preventing or suppressing the influence of the color (substrate color) of the workpiece and / or surrounding components on which the ink coating is formed. Note that dyes that are difficult to discolor in a plasma treatment atmosphere may include those that undergo slight discoloration due to physical etching in a plasma treatment atmosphere.

[0060] Photopolymerization initiator, silica, and hydrophobic alumina The ink composition may contain at least one selected from the group consisting of a photopolymerization initiator, silica, and hydrophobic alumina as a color change accelerator to improve the color change rate of organic dyes under a plasma treatment atmosphere. Here, hydrophobic alumina means alumina that has been surface-treated with a compound having a hydrophobic group. Examples of hydrophobic groups include dimethylsilyl group, trimethylsilyl group, dimethylpolysiloxane group, dimethylsiloxane group, aminoalkylsilyl group, alkylsilyl group, and methacrylatesilyl group. By using these color change accelerators in combination with organic dyes, excellent detection sensitivity can be obtained, and the color change rate can also be controlled by adjusting the content of the color change accelerator.

[0061] The detailed reasons why the photopolymerization initiator, silica, and hydrophobic alumina each act as discoloration accelerators are unknown, but it is thought that the photopolymerization initiator and hydrophobic alumina each generate radicals in a plasma treatment atmosphere, thereby changing the structure of the organic dye (partial decomposition, bond cleavage, etc.), and thus exerting a discoloration-accelerating effect. Furthermore, it is thought that silica exerts a discoloration-accelerating effect because its porous surface increases the surface area to which the organic dye adheres, and because silica makes the surface of the coating film (discoloration layer) of the ink composition of the present invention porous, creating an environment that is easily exposed to plasma.

[0062] While not limited to specific photopolymerization initiators, at least one selected from the group consisting of alkylphenone-based photopolymerization initiators, acylphosphine acetide-based photopolymerization initiators, titanocene-based photopolymerization initiators, acetophenone-based photopolymerization initiators, benzophenone-based photopolymerization initiators, thioxanthone-based photopolymerization initiators, cationic photopolymerization initiators, and anionic photopolymerization initiators is preferred. Among these photopolymerization initiators, at least one alkylphenone-based photopolymerization initiator and an acylphosphine acetide-based photopolymerization initiator is more preferred.

[0063] The amount of photopolymerization initiator can be appropriately determined depending on its type and the type of organic dye used, but considering the shelf life and color change acceleration effect in the ink composition, it is generally desirable to have an amount of about 0.05 to 20% by weight, and especially 1 to 10% by weight, in the ink composition. If the amount of photopolymerization initiator exceeds 20% by weight, there is a risk that it will not dissolve in the ink composition and will remain undissolved. Also, if the amount of photopolymerization initiator is less than 0.05% by weight, there is a risk that the color change acceleration effect will not be sufficiently exhibited.

[0064] While not limited to silica, hydrophobic silica is preferred, for example. The silica may be surface-treated to impart hydrophobicity. The average particle size of the silica is not limited, but 5 to 100 nm is preferred, and 5 to 50 nm is more preferred.

[0065] The silica content can be appropriately determined depending on the type of silica and the type of organic dye used, but considering the preservation properties and discoloration-accelerating effect in the composition, it is generally desirable to have approximately 1 to 30% by weight, and particularly 2 to 20% by weight, in the ink composition. If the silica content exceeds 20% by weight, the discoloration-accelerating effect may not be fully realized. Also, if the silica content is less than 0.1% by weight, the discoloration-accelerating effect may not be fully realized.

[0066] The hydrophobic alumina is not limited to alumina that has been surface-treated with a compound having hydrophobic groups. Untreated alumina and hydrophilic alumina can be used as fillers as described below, but these are clearly distinguished from hydrophobic alumina by the presence or absence of surface treatment and the type of surface treatment. The average particle size of hydrophobic alumina is not limited, but is preferably 5 to 100 nm, and more preferably 5 to 50 nm.

[0067] The amount of hydrophobic alumina can be appropriately determined depending on the degree of hydrophobicity and the type of organic dye used, but generally, considering the preservation properties and discoloration-promoting effect in the composition, it is included in the ink composition. The hydrophobic alumina content should be approximately 0.5 to 50% by weight, and preferably 1 to 30% by weight. If the hydrophobic alumina content exceeds 50% by weight, the adhesion of the ink composition's coating film may decrease. If the hydrophobic alumina content is less than 0.5% by weight, the discoloration-accelerating effect may not be fully realized.

[0068] Binder resin As the binder resin, known resin components that have been used in ink compositions for writing, printing, etc., can be used as is. For example, maleic acid resin, ketone resin, polyvinyl butyral resin, cellulose resin, acrylic resin, styrene maleic acid resin, styrene acrylic acid resin, polyester resin, polyamide resin, polyacrylonitrile resin, polyimide resin, polyvinylpyrrolidone resin, polyacrylamide resin, polyvinylimidazole resin, polyethyleneimine resin, amino resin, etc.

[0069] In this invention, cellulose-based resins can be used particularly suitably. By using cellulose-based resins, excellent adhesion can be obtained even if the ink composition contains silica, hydrophobic alumina, fillers, etc., and peeling and detachment from the substrate can be effectively prevented after the ink composition coating film has been formed on the substrate. Furthermore, by effectively creating multiple cracks on the surface of the ink composition coating film, it is thought that an environment that is easily exposed to plasma is created, thus exhibiting a discoloration-accelerating effect.

[0070] In the present invention, polyvinyl butyral resin can be suitably used. By using polyvinyl butyral resin, the lightfastness of the ink composition containing organic dyes and its coating film can be improved compared to cases where other binder resins (especially cellulose-based resins) are used or where no binder resin is used. Specifically, when the ink composition and its coating film are irradiated with light containing ultraviolet rays, such as from a fluorescent lamp, some discoloration may be observed even without plasma treatment. However, by using polyvinyl butyral resin as the binder resin, discoloration of the ink composition and its coating film when irradiated with light containing ultraviolet rays can be suppressed, thereby improving lightfastness.

[0071] The binder resin content can be appropriately determined depending on the type of binder resin, the type of organic dye used, etc., but generally it is desirable to have about 50% by weight or less, and particularly 3 to 35% by weight, in the ink composition. When using a nitrogen-containing polymer as the binder resin, it is desirable to have about 0.1 to 50% by weight, and particularly 1 to 20% by weight, of the nitrogen-containing polymer in the ink composition. Note that the binder resin content affects the discoloration rate of the discoloration layer; a higher binder resin content tends to slow down the discoloration rate, while a lower binder resin content tends to speed up the discoloration rate. Therefore, to adjust the discoloration rate to be faster, an ink composition that does not contain binder resin can also be used.

[0072] Other additives The ink composition may optionally contain known ink components such as solvents, fillers, leveling agents, defoamers, UV absorbers, and surfactants.

[0073] As a solvent, any solvent commonly used in ink compositions for printing, writing, etc., can be used. For example, various solvents such as alcohols, polyhydric alcohols, esters, ethers, ketones, hydrocarbons, and glycol ethers can be used, and should be appropriately selected depending on the solubility of the organic dye and binder resin used. One or more of the above solvents can be used. In addition, for the ink composition to be filled into the direct-liquid marker used in the present invention, it is preferable to use an organic solvent as the solvent, in terms of the fluidity of the ink suitable for a direct-liquid marker and the drying properties (fast drying) after the formation of the ink film. A mixed solvent of propylene glycol monomethyl ether (PM) and isopropyl alcohol (IPA) is preferable. When a mixed solvent of PM and IPA is used, if the total amount of PM and IPA is 100% by mass, and the mass ratio of PM / IPA is in the range of PM / IPA = 4 / 1 to 1 / 4, the drying properties (fast drying) of the ink film after writing are good, and it is easy to adjust the thickness of the ink film by applying multiple coats. Furthermore, a mixed solvent of PM and IPA is easier to use because it has better shelf life compared to solvents primarily composed of ethanol, and has a reduced odor compared to solvents primarily composed of ethyl acetate.

[0074] When using organic solvents as the solvent, since all organic solvents have low surface tension, ink can be written on a wide range of materials, especially non-absorbent surfaces, without repelling the ink, and an ink coating can be formed.

[0075] The solvent content can be appropriately determined depending on the type of solvent and organic dye used, but it is generally desirable to have about 40-95% by weight, and particularly 60-90% by weight, in the ink composition. Generally as described above, the fluidity of the ink changes depending on the diameter or porosity of the writing part (tip) of the direct-ink marker, so it is preferable to adjust the type and content of the solvent as appropriate to obtain the desired fluidity. This is also true when the direct-ink marker is changed to another dispensing device (dispenser, inkjet printer, or pad printer) as a modification of the present invention.

[0076] Each component of the ink composition can be added simultaneously or sequentially and mixed uniformly using a known stirrer such as a homogenizer or dissolver. For example, the solvent can be first mixed with an organic dye, and at least one of a color change accelerator and a binder resin in sequence, and finally, an extender can be added as needed, and then mixed and stirred with a stirrer.

[0077] As mentioned above, the drying properties (fast drying properties) of the ink coating can be adjusted by adjusting the type of solvent contained in the ink composition. However, in embodiments where the plasma processing system of the present invention should be performed quickly, an accelerated drying device and a cooling device may be further provided between the application device and the plasma irradiation device, as illustrated in Figure 13(c), to accelerate the drying and stabilize the ink coating formed by the application device at an early stage. Examples of the accelerated drying device include devices that use one or more types of heating, such as blowing air, hot air, and IR heating. Although Figure 13(c) shows an embodiment equipped with both an accelerated drying device and a cooling device, an embodiment equipped with only a heating drying device may also be used.

[0078] Figure 7 shows an example of plasma treatment performed on substrates representing various workpieces and / or surrounding components by forming an ink coating using a direct-liquid marker filled with plasma indicator ink containing an organic solvent. The substrates used were transparent PET (Toray Industries' "Lumirror Film T60"), white foamed PET (Toyobo's "Crisper K2323"), copper (the copper foil side of Taiyo Technorex's "Flexible Copper-Clad Laminate (Laminate of Copper Foil and Polyimide Insulating Film)"), polyimide (the polyimide insulating film side of Taiyo Technorex's "Flexible Copper-Clad Laminate (Laminate of Copper Foil and Polyimide Insulating Film)"), and glass epoxy substrate (Taiyo Technorex's "FR-4 Substrate"). For comparison, results using a conventional long-label type plasma indicator are also included. Plasma treatment was performed using a long-length atmospheric pressure plasma device ("AP-2000" manufactured by Denshi Giken Co., Ltd.) under the following conditions: gas (Dry air 50 SLM), output (7.0 kV), and treatment time (1 second, 4 seconds).

[0079] The results in Figure 7 show that an ink coating could be formed on various substrates by writing (filling) with a direct-ink marker without the ink repelling. Regarding the degree of discoloration of the ink coating after plasma treatment, some discoloration due to uneven application (differences in film thickness) by the experimenter was observed, but discoloration of the ink coating could be visually confirmed even on dark-colored substrates such as copper and polyimide. Although some discoloration unevenness may occur after plasma treatment when writing (filling) with a direct-ink marker, it was confirmed that the discoloration performance is substantially the same as that of conventional long-label type plasma indicators. In actual plasma treatment systems, uneven application (differences in film thickness) can be prevented or suppressed by mechanically controlling the writing using an application device equipped with a direct-ink marker. Furthermore, in the experiment in Figure 7, after forming an ink coating on a highly flexible PET substrate, the ink coating did not peel off even when the substrate was bent. This means that it is highly useful for plasma treatment of films and the like that performed roll-to-roll.

[0080] Figures 8 and 9 show the relationship between differences in film thickness due to the number of coats applied, differences in plasma treatment time, and differences in discoloration when an ink coating film is formed by writing (filling) with a direct-ink marker filled with plasma indicator ink containing an organic solvent. Plasma treatment was performed using a long-length atmospheric pressure plasma device (Electronic Technology Research Institute "AP-2000") under the following conditions: gas (Dry air 50SLM), output (7.0kV), and treatment time (2 seconds, 4 seconds).

[0081] When the number of coats was small (for example, one coat in Figure 8), the film thickness was smallest, and the color difference △E*ab of the ink coating after plasma treatment was large. The color difference △E*ab was measured using a colorimeter (Konica Minolta "FD-5"). This is because, as illustrated in Figure 9, even with the same plasma intensity, if the ink coating is thin, all of the color-changing pigment may disappear, whereas if the ink coating is thick, some of the color-changing pigment remains. In other words, by repeatedly writing (filling in) with a direct-ink marker, the film thickness of the ink coating can be easily adjusted (thickened), allowing for appropriate adaptation to plasma treatments of various intensities. This eliminates the need to prepare and select multiple types of indicators according to the plasma intensity, as with conventional label-type or card-type (sheet-type) indicators and chemical indicators (CI).

[0082] Figure 10 shows the discoloration when a portion of a substrate (the white PET mentioned above), representing the workpiece and / or surrounding components, is plasma-treated after drawing multiple parallel lines at intervals using a direct-liquid marker filled with plasma indicator ink containing an organic solvent. For comparison, results using a conventional sheet-type plasma indicator are also included. Plasma treatment was performed using a handheld atmospheric pressure plasma device (Relyon Plasma's "Piezo Brush PZ3") for 40 seconds. From the results in Figure 10, it was possible to confirm the distribution of plasma irradiation, similar to that of the conventional sheet-type plasma indicator, even when an ink film (multiple parallel lines) was formed using a direct-liquid marker. A characteristic of the Piezo Brush PZ3 is that the plasma irradiation is not perfectly homogeneous, and plasma is particularly strongly irradiated from the edge of the electrode. Both the direct-liquid marker and the conventional sheet-type plasma indicator showed discoloration that reflected this characteristic.

[0083] Figure 11 shows the discoloration of substrates (a φ4mm PP pipe as a thin workpiece, and a 20ml glass volumetric flask as a curved workpiece) that are assumed to be workpieces and / or peripheral components to which conventional label-type or card-type (sheet-type) indicators or chemical indicators (CIs) cannot be attached or are difficult to attach, by writing with a direct-liquid marker filled with plasma indicator ink containing an organic solvent and then plasma treatment. Plasma treatment was performed using a handheld atmospheric pressure plasma device (Relyon Plasma's "Piezo Brush PZ3") for a treatment time of 60 seconds. From the results in Figure 11, discoloration was observed only in the plasma-irradiated portion of the ink film, demonstrating that by forming an ink film by writing with a direct-liquid marker, it was possible to easily form an ink film even on thin workpieces and workpieces with curved surfaces and confirm the effect of plasma treatment.

[0084] (Measuring device) The plasma processing system of the present invention includes a measuring device for measuring the optical properties of the ink coating film that has been irradiated with plasma.

[0085] Examples of measuring devices include those equipped with a colorimeter. In this case, any device capable of measuring the difference in chromaticity (color difference) △E*ab between the chromaticity L*a*b* of the ink coating before and after plasma treatment is sufficient. Here, if the chromaticity of the ink coating before plasma treatment is L*1, a*1, b*1, and the chromaticity of the ink coating after plasma treatment is L*2, a*2, b*2, then △E*ab is expressed as follows, and by comparing the pre-inputted △E*ab with the achievement rate of the plasma treatment, the suitability of the plasma treatment can be determined.

[0086] Color difference △E*ab=[(L*2-L*1) 2 +(a*2-a*1) 2 +(b*2-b*1) 2 ] 1 / 2

[0087] The optical properties of the ink coating film before plasma treatment can be known in advance and representative values ​​can be used, depending on the conditions of the coating apparatus and the type of plasma indicator ink to be applied. However, from the viewpoint of measuring △E*ab more precisely, a preliminary measuring device for measuring the optical properties of the ink coating film before plasma treatment may be provided, as illustrated in Figure 13(b). Similar to the measuring device, the preliminary measuring device may include, for example, a measuring device equipped with a colorimeter. This allows the chromaticity L*1, a*1, b*1 of the ink coating film before plasma treatment to be measured using the preliminary measuring device, and then the chromaticity L*2, a*2, b*2 of the ink coating film after plasma treatment to be measured using the measuring device, enabling a more precise measurement of △E*ab and a determination of the suitability of plasma treatment.

[0088] Furthermore, the measuring device may be a spectrophotometer or a transmittance meter if the object to be treated and / or surrounding components are transparent. In this case, since the object to be treated and / or surrounding components are transparent, the difference in transmittance of light passing through the ink coating and its substrate (the object to be treated and / or surrounding components) before and after plasma treatment can be measured, and the suitability of the plasma treatment can be determined by comparing the transmittance difference, which was input in advance, with the success rate of the plasma treatment.

[0089] (removal device) The plasma treatment system of the present invention includes a removal device for removing the ink coating film that has been irradiated with plasma.

[0090] The removal device is not limited to those that have the function of removing the ink coating after plasma treatment, but examples include: a device that removes the ink coating by applying or spraying an aqueous solvent or organic solvent and then wiping it off; a device that removes the ink coating by wiping it with a wiping material (impregnable material such as a sponge or cloth) impregnated with an aqueous solvent or organic solvent; a device that removes the ink coating by mechanically rubbing it off; a device that removes the ink coating by peeling it off using adsorption or adhesive force; a device that removes the ink coating by spraying a high-pressure fluid; a device that removes the ink coating by irradiating it with laser light; and a device that removes the ink coating by physical or chemical etching. Such a device can be selected according to the type (material) of the object to be treated and / or surrounding components, and the type of ink coating.

[0091] In the embodiment of removing the ink coating by wiping with an aqueous or organic solvent, the solvents listed in the section on plasma indicator inks can be used, and any solvent commonly used in ink compositions for printing, writing, etc., can be used. For example, various solvents such as alcohols, polyhydric alcohols, esters, ethers, ketones, hydrocarbons, and glycol ethers can be used.

[0092] The plasma treatment method of the present invention can be carried out by using the plasma treatment system of the present invention described above. Specifically, the plasma treatment method of the present invention is: A plasma treatment method in which plasma is irradiated onto an object to be treated, (1) An application step in which an ink coating of plasma indicator ink whose optical properties are changed by plasma irradiation is applied to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece inside a plasma irradiation device, wherein the application step includes an application step using a direct-liquid marker which is an application device loaded with plasma indicator ink, (2) A plasma irradiation step of irradiating the workpiece and the surrounding members with plasma, (3) A measurement step of measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal step to remove the plasma-irradiated ink coating, It is characterized by having the following features.

[0093] The description of each step of the plasma processing method of the present invention is the same as the description of the embodiments of each device in the plasma processing system of the present invention described above. The description of the application step corresponds to the description of the application device, the description of the plasma irradiation step corresponds to the description of the plasma irradiation device, the description of the measurement step corresponds to the description of the measurement device, and the description of the removal step corresponds to the description of the removal device.

Claims

1. A plasma treatment system that irradiates an object to be treated with plasma, (1) A direct-liquid marker, which is a device loaded with plasma indicator ink, that applies an ink coating film whose optical properties change due to plasma irradiation to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece, inside a plasma irradiation device, (2) A plasma irradiation device that irradiates the object to be processed and the surrounding members with plasma, (3) A measuring device for measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal device for removing the plasma-irradiated ink coating, A plasma processing system characterized by comprising the following features.

2. The direct-liquid marker comprises an ink reservoir and a writing section, with a valve interposed between them and connected to the writing section, the writing section being supported from the axial center to the rear end by a cylindrical ink absorber installed in the tip stopper, a valve body connected to the rear end of the writing section, the valve having a valve body and a valve chamber, the valve chamber having an opening on the reservoir side communicating with the ink reservoir and an opening on the writing section side communicating with the writing section, and the valve body being disposed therein, the valve body normally closing the opening on the writing section side while the opening on the reservoir side is open, and the valve body moving and opening the opening on the writing section side when the writing section is pressed, the plasma processing system according to claim 1.

3. The plasma treatment system according to claim 1, wherein the plasma irradiation device is a reduced-pressure plasma irradiation device or an atmospheric pressure plasma irradiation device.

4. The plasma treatment system according to claim 1, wherein the peripheral member is at least one selected from the group consisting of a carrier, tray, table, board, magazine, cassette, packaging (pouch) containing the workpiece, which is located inside the plasma irradiation device and holds the workpiece; a dummy workpiece having the same shape as the workpiece; a transfer device that lifts and / or moves the workpiece; and a conveyor for transporting the workpiece.

5. The plasma processing system according to claim 1, wherein the measuring device is a colorimeter for measuring the color difference of the plasma-irradiated ink coating film before and after plasma irradiation, or a transmission spectrometer for measuring the difference in transmittance of the plasma-irradiated ink coating film before and after plasma irradiation.

6. The plasma treatment system according to claim 1, wherein the removal device dissolves and removes the plasma-irradiated ink coating using a solvent.

7. A plasma treatment method in which plasma is irradiated onto an object to be treated, (1) An application step in which an ink coating of plasma indicator ink whose optical properties change due to plasma irradiation is applied to the workpiece and / or a peripheral member that is plasma-irradiated together with the workpiece inside a plasma irradiation device, wherein the application step includes an application step using a direct-liquid marker which is an application device loaded with plasma indicator ink, (2) A plasma irradiation step of irradiating the workpiece and the surrounding members with plasma, (3) A measurement step of measuring the optical properties of the ink coating film that has been irradiated with plasma, (4) A removal step to remove the plasma-irradiated ink coating, A plasma treatment method characterized by comprising the following:

8. The direct-liquid marker comprises an ink reservoir and a writing section, with a valve interposed between them and connected to the writing section, the writing section being supported from the axial center to the rear end of the writing section by a cylindrical ink absorber installed in the tip stopper, a valve body connected to the rear end of the writing section, the valve having a valve body and a valve chamber, the valve chamber having an opening on the reservoir side communicating with the ink reservoir and an opening on the writing section side communicating with the writing section, and the valve body being disposed therein, the valve body normally closing the opening on the writing section side while the opening on the reservoir side is open, and the valve body moving and opening the opening on the writing section side when the writing section is pressed, the plasma treatment method according to claim 7.

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