JPH0559560A - Utilization of plasma reaction at atmos- pheric pressure and device therefor - Google Patents

Abstract

PURPOSE: To make it possible to inexpensively treat a large amt. of powder surfaces in a vapor phase method by utilizing reactive gaseous plasma which has high reaction activity and high stability under the atm. pressure.

CONSTITUTION: A reaction vessel 1 is at least internally provided with a grounding electrode 7 formed by covering a metallic electrode 17 with a dielectric substance 18 (20) and a high voltage impressing electrode 8. The introduction of a rare gas into the reaction vessel 1 is made possible by a rare gas supply pipe 10 and the introduction of a gaseous monomer into the reaction vessel 1 is made possible by a gaseous monomer supply pipe 14. Further, the introduction of other gases into the reaction vessel 1 is made possible by an other gas supply pipe 13. The specified gases are discharged from the reaction vessel 1 by a waste gas pipe 15. The powder is put into the reaction vessel 1 and the rare gas, gaseous monomer, other gases, etc., are introduced into the reaction vessel according to the powder and electric power is supplied to the grounding electrode 7 and the high voltage impressing electrode 8 to induce the atm. pressure plasma reaction. As a result, the reforming of the surfaces of the powder is made possible.

COPYRIGHT: (C)1993,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of utilizing an atmospheric pressure plasma reaction and an apparatus therefor, and more specifically, to highly efficiently reform the surface of powder by high stability glow discharge plasma under atmospheric pressure. The present invention relates to a method of using an atmospheric pressure plasma reaction and an apparatus therefor.

[0002]

2. Description of the Related Art Generally, it is well known that plasma is a substance which is strongly ionized and separated into ions and electrons and is almost neutral as a whole, but its characteristics are different from those of a neutral gas. On the street. This plasma can usually be obtained artificially by discharging a gas.

By the way, as a technique for applying such plasma, a film forming method and a surface modification method utilizing low-pressure glow discharge plasma are widely known, and they are industrially applied to various fields. There is a so-called organic plasma method as one of the surface treatment methods using such low-pressure glow discharge plasma, and this organic plasma method is a method of forming a thin film and modifying the surface by converting an organic compound gas into plasma. Furthermore, using the plasma in the vacuum container,
A method for producing diamond powder or ultrafine particle powder or for surface modification has also been proposed.

[0004]

However, according to these conventional surface treatment methods using low-pressure glow discharge plasma, since all of them are reactions under a vacuum of about 10 ^-5 to 10 ^-3 [Torr], low pressure Since a vacuum device and the equipment are required, and discontinuous processing (batch processing) or the like, it takes time to manufacture and there is no choice but to increase the manufacturing cost. Further, in the case of a surface treatment method for powder or the like, the surface of a pigment or the like is treated by a wet method with a resin or various acids, alkalis, surfactant-containing surfactant solution aerosols, etc., and the process of drying, pulverizing, classifying, etc. is performed. Since it is necessary, there is a drawback that the equipment, the processing time, the processing process and the like are considerably complicated and the waste liquid needs to be processed.

In view of the above problems, the present invention has been made in view of the above problems.
(EN) Provided are a method of utilizing an atmospheric pressure plasma reaction and a device therefor capable of treating a large amount of powder surface by a gas phase method at a low cost by utilizing a highly stable reactive gas plasma having a large reaction activity under atmospheric pressure. The purpose is to

[0006]

In order to achieve the above object, a method of utilizing an atmospheric pressure plasma reaction according to the invention of claim 1 is to use a high voltage applying electrode and a ground electrode which are formed by covering a metal electrode with a dielectric. Put powder in the configured reaction vessel,
A rare gas or a monomer gas is introduced alone or as a mixture, and electric power is supplied to the high-voltage applying electrode and the ground electrode to excite plasma under atmospheric pressure to treat the powder surface. is there.

In the method of utilizing the atmospheric pressure plasma reaction according to the second aspect of the present invention, the powder is put in a reaction container composed of a high voltage applying electrode and a ground electrode, which are formed by covering a metal electrode with a dielectric. A rare gas or a monomer gas is introduced alone or in a mixture, and another gas is introduced, and electric power is supplied to the high voltage applying electrode and the ground electrode to excite the plasma under atmospheric pressure to treat the powder surface. It is characterized by doing. In the invention according to claim 2, the other gas is a solvent gas, a gas of an organic acid or an inorganic acid, a complex gas thereof, or an alkaline gas,
Alternatively, a surfactant-containing solution aerosol may be used.

Further, an atmospheric pressure plasma reactor according to the invention of claim 6 is provided with a reaction vessel for causing an atmospheric pressure plasma reaction, and is provided at least inside the reaction vessel, and a metal electrode is covered with a dielectric. A high voltage applying electrode and a ground electrode configured, a rare gas supply pipe for introducing a rare gas into the reaction container, a monomer gas supply pipe for introducing a monomer gas into the reaction container, and the inside of the reaction container Another gas supply pipe for introducing another gas into the chamber, and an exhaust gas pipe for discharging a certain gas from the reaction container are provided. In the invention according to claim 6, as the dielectric material of the high voltage applying electrode and the ground electrode, it is preferable to use a liquid dielectric alone or in combination with a solid dielectric.

[0009]

According to the first aspect of the present invention, the rare gas and the monomer gas are introduced into the reaction vessel having the ground electrode and the high voltage applying electrode, which are formed by covering the metal electrode with the dielectric, alone or as a mixture. The surface of the powder is treated by stably generating atmospheric pressure plasma by the interaction between the ground electrode constituted by covering the metal electrode with a dielectric, the high voltage applying electrode and the introduced gas. As a result, the powder has improved dispersibility, redispersibility, cohesiveness, anti-settling property, binding property, kneading property, and the like.

According to the second aspect of the present invention, the rare gas and the monomer gas are introduced individually or as a mixture into the reaction vessel having the high voltage applying electrode formed by covering the metal electrode with the dielectric material. Solvent gas as a gas, organic acid, inorganic acid, a single or mixed gas of surfactant-containing surfactant solution aerosol is introduced at appropriate times, a ground electrode constituted by covering a metal electrode with a dielectric, a high-voltage applying electrode and a plurality of introduction gases. The surface of the powder is treated by stably causing an atmospheric pressure plasma reaction due to the interaction of. As a result, the powder has improved dispersibility, redispersibility, cohesiveness, anti-settling property, binding property, kneading property, and the like.

Further, according to the invention of claim 6, the high voltage applying electrode or the ground electrode is covered with a dielectric material to form a spirally wound electrode, and the opposite polarity electrode of the polarity is covered with a dielectric material to form a spiral. The counter electrode is inserted by inserting it in the center of the electrode. Then, these are installed inside the reaction vessel, and a rare gas and a monomer gas are introduced individually or in a mixed manner, and / or a solvent gas as another gas, an organic acid, an inorganic acid, or a surfactant-containing aerosol alone or. It is possible to treat the surface of the powder by glow discharge plasma having high activity and high stability under atmospheric pressure by introducing the mixed gas at appropriate times. This makes it possible to realize the above two processing methods. Further, when the treatment method is realized by the device, the powder has a dispersibility, a redispersibility,
To add primary value such as cohesiveness, anti-settling property, cohesiveness, kneading property, etc., to add to other substances in powder, to strengthen and strengthen the effect of filler, and to improve its performance and function. Become.

[0012]

The present invention will be described below. Figure 1
FIG. 1 is a configuration diagram showing an embodiment of an atmospheric pressure plasma reactor of the present invention. In FIG. 1, for example, a reaction vessel 1 made of a Pyrex bell jar reaction vessel is a lower vessel 1a.
The upper container 1b is detachable on the upper part of the container, and when in use, the O-ring 2 is interposed between the lower container 1a and the upper container 1b so that they can be joined by the clamp 3.
Inside the reaction vessel 1, a filter 4 for preventing powder scattering is installed in a part of the upper vessel 1b.
Further, the powder is easily rolled up on the bottom of the lower container 1a, and the powder is accumulated on the bottom, and the mesh 5 is laid so as not to cause inconvenience in processing. A vacuum exhaust pipe 6 is connected to the reaction container 1, and when the reaction container 1 is used,
When it is necessary to remove air or the like in the interior or in the powder, the internal air or the like is exhausted from the vacuum exhaust pipe 6 and the pressure is reduced to 10 ^-3 [To
rr]. When the vacuum exhaust pipe 6 needs a trap, it may be installed between the vacuum exhaust pipe 6 and a vacuum pump (not shown).

A ground electrode 7 is provided at the center of the inside of the reaction vessel 1.
Are provided in a straight line, and a high voltage applying electrode 8 is provided in a line around the ground electrode 7. A ground electrode 9 is provided around the lower container 1a of the reaction container 1.
The ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9
Discharges well even if the polarity is reversed, but it is more convenient to use the above-mentioned polarity. Further, the ground electrode 9 may have a spiral shape, but it is more preferable to wind a metal wire net such as stainless steel, or a wire net with a dielectric material laminated on both sides. As the dielectric coating material used at this time, glass, ceramics, plastics and the like can be used, but insulating oil may be applied, and various rubbers mixed with insulating oil and vulcanized rubber, etc. It is possible to use those obtained by crosslinking reaction with. Of course, an insulating oil may be impregnated into a base material and wound around a conductive metal to form an electrode. Furthermore, insulating oil may be injected into the tube and a metal electrode may be inserted to form an electrode. This is to prevent the solid dielectric from being deformed and destroyed by heat strain when the electrode part generates heat, and by using insulating oil, the circulation cooling device can be used and the heat generation of the electrode part can be controlled. It is also possible to prevent the transition to arc discharge as the substrate temperature rises. Further, by using the liquid dielectric, there are advantages that the area of the discharge electrode portion can be easily expanded, and the processing and manufacturing are easy.

The rare gas supply pipe 10 is connected to the bottom of the reaction vessel 1 via a flow meter 11a and a bubbling device 12a. Further, the other gas supply pipe 13 includes a flow meter 11b,
It is connected to the bottom of the reaction vessel 1 via a bubbling device 12b. The rare gas supply pipe 10 and the other gas supply pipe 13 can supply the gas individually or in a mixture. In addition, the monomer gas supply pipe 14 is connected to the bottom of the reaction vessel 1 via the flowmeter 11c in the same manner as described above, and the rare gas supply pipe 10 and the monomer gas supply pipe 14 can supply a single gas or a mixed gas. It is possible. By the rare gas supply pipe 10, the other gas supply pipe 13, and the monomer gas supply pipe 14, the flow rate of each supply gas is adjusted by the flow meters 11a, 11b, and 11c, and the supply gas is introduced into the reaction vessel 1.

An exhaust gas pipe 15 is connected to the upper container 1b of the reaction container 1, and a filter 16 is provided in the middle of the exhaust gas pipe 15. When the exhaust gas pipe 15 exhausts to the outside air, the filter 4 may have a size that allows the exhaust gas to pass and does not pass the powder, for example, 0.01
It is desirable to set it to 250 [micron]. In particular, 0.1
Approximately 50 [micron] is preferable. Also, the reaction container 1
When reusing rare gas such as He inside the
As the filter 4, it is desirable to use one having a diameter of 0.01 to 5 [micron]. The powder sample is mesh 5
Is placed in the central part of the reaction vessel 1 so as to diffuse inside the reaction vessel 1 together with the supply gas.

Next, the structures of the ground electrode 7 and the high voltage applying electrode 8 will be described with reference to FIGS. Figure 2
FIG. 3 is an explanatory view showing a specific structure of a ground electrode 7 and a high voltage applying electrode 8 used in the reaction container 1. In FIG. 2, the ground electrode 7 and the high voltage applying electrode 8 are the metal electrode 1
7 is covered with a dielectric coating material 18. Here, as the dielectric coating material, glass, ceramics, plastic, or the like can be used. FIG. 3 is an explanatory diagram showing a specific configuration of the ground electrode 7 and the high voltage applying electrode 8 when the liquid dielectric is used.

In FIG. 3, the ground electrode 7 and the high-voltage applying electrode 8 are formed by covering the metal electrode 17 with a container 19 and enclosing the liquid dielectric 20 inside the container 19. Here, what can be used as the liquid dielectric 20 is a hydrocarbon-based synthetic insulating oil represented by alkylbenzene, polybutene, diphenyl pentachloride, etc., chlorinated synthetic oil, mineral oil, silicone oil, fluorine oil, etc. Used alone.
When used alone, the metal used for the metal electrode 17 is
Aluminum, alloys of alloys such as tin, zinc and nickel, or stainless steel are preferable to copper.

Further, in the ground electrode 7 and the high voltage applying electrode 8, the liquid dielectric 2 provided around the metal electrode 17 is provided.
0 may be impregnated into a suitable substrate. Further, these liquid dielectrics 20 may be kneaded with another resin, rubber or the like, or may be a crosslinked hard film. When used at a relatively low power, rubber systems such as high-density polyethylene, nitrile rubber, urethane rubber are easy to handle. Alternatively, a cross-linked type of polyvinyl alcohol and polyvinyl acetal can be used. Further, as the material of the container 19, Pyrex glass, alumina ceramics, titanium sun value ceramics, and the like are more practical. For example, silicon (GE 96, SF96) or the like may be enclosed in a container 19 made of a heat-resistant glass tube such as Pyrex glass to serve as the ground electrode 7 or the high-voltage applying electrode 8.

Next, in the reaction vessel 1 having the above-mentioned structure,
The operation of plasma discharge will be described below. First, the gas introduced into the reaction vessel 1 is an important element for stabilizing atmospheric pressure glow discharge, and will be described in detail below. Gases such as helium (He), neon (Ne), argon (Ar), and nitrogen (N ₂ ) can be used as the rare gas.
As the monomer gas, unsaturated hydrocarbons, halogens and other hydrocarbons having or not having a functional group can be used. In particular, the hydrocarbon compound having a halogen functional groups, for example _{CF 4, C 2 F 4,} C 3 F 8, (CH 3) 3 B
Etc. are good.

Solvents used as other gases As the solvent of the gas, hydrocarbons, halogenated hydrocarbons, alcohols, ethers, acetals, ketones, esters, polyhydric alcohols and their derivatives, fatty acids and phenols, nitrogen compounds,
Includes sulfur, phosphorus and other compounds, and inorganic solvents. The other gas can be selected as appropriate depending on the type of powder to be treated, but these solvent gases can be used alone or in combination. Organic acids used as other gas include carboxylic acid (RCOOH) and sulfonic acid (RSO).
₃ ), sulfinic acid (RSO ₂ ), phenol (ArO
H), enol (RCH = C (OH) R, thiophenol (ArSH), imide (RCONHCOR), oxime (RCH = NOH), aromatic sulfonamide (ArSO)
2NH2), nitro compounds (RCH ₂ NO ₂ R ₂ CHN
O ₂ ) can be used, but formic acid, maleic acid, fumaric acid or the like alone or a dissolved product of water, an alcohol solvent or the like is preferable. As the inorganic acid, hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid or the like can be used.

Surfactant-containing solution aerosols used as other gases include cation type, anion type, nonion type, silicon type, fluorine and fluorocarbon type, hydrocarbon type, fatty acid and amide type, ester type, alcohol type and metal. A soap or the like alone or a dissolved product of water or a solvent is used. The addition amount is 0.001 [ppm] -50
[%], Preferably 0.01 [ppm] -5 [%] is desirable.

Next, the treatable powder will be described below. Here, as the powder that can be treated, any powder of an organic substance or an inorganic substance may be used. First, an organic powder will be described as a powder that can be treated.
Organic dye, starch protein powder, fat powder, carbohydrate powder, vitamin powder, enzyme powder, resin fine powder, organic carbonized fine powder,
Cellulose and its derivative powder are included. In particular, as organic pigments, a) neutral nitro pigments, azo pigments, anthraquinone pigments, phthalocyanine pigments, and azine pigments are used.
Cation type, triphenylmethane type, xanthene type, c) Anion type, azo type, triphenolmethane type, d) Others, anthraquinone type, dioxazine type, quinacridone type, e) carbon black ( Bone black) etc. are considered. On the other hand, as organic dyes, azo type, azo metal complex, azomethine type, diarylide type, monoazo type, anthanthrone type, pyranthrone type, perion type, isoindolinone type, quinophthalone type, anthrapyrimidein type, phthalocyanine type , Indanthrone, nigrosine, perinone, quinoline, coumarin, thioindigo and the like.

Next, the inorganic powder will be described as the processable powder. The inorganic powder includes inorganic pigments, that is, white pigments composed of inorganic compounds, calcium carbonate (CaCo ₃ ), titanium oxide ( TiO ₂ ), zinc oxide (ZnO), silicon dioxide (SiO ₂ ), talc,
Calcium oxide (CaO), calcium phosphate-based, apatite, vanadium (V), chromium (Cr), manganese (M
n), iron (Fe), cobalt (Co), nickel (N
i), molybdenum (Mo), tungsten (W), mercury (Hg), lead (Pb), antimony (Sb), and other substances composed of colored transition elements, and sulfur (S), selenium (S).
Pigments containing e), fine metal powders, etc. are included.

Further, the soil primary minerals will be explained as the powders which can be treated. The soil primary minerals include a) orthosilicates of muscovite, biotite, glauconite and zircon.
b) Metamorphic acid silicates, c) Polysilicic acid, orthoclase, albite, anorthite, plagioclase; d) Quartz, magnetite, titanite as oxides, and f) Phosphates. A) and g) limestone as a carbonate. In addition, the soil secondary mineral will be described as a powder that can be treated. Examples of the soil secondary mineral include clay mineral, kaolinite, halosite, hydrohalloysite, illite, vermiculite, montmorillonite, hydelite, nonronite, saponite, It includes chlorite, attapulgite, gibbsite, hematite, goethite, limonite, pyrrolcite, allophane and the like.

Further, ceramics will be described as the powder that can be treated. For the ceramics, the metal oxides include barium titanate (BaTiO ₃ ) system, aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), and oxide. Silicon (SiO ₂ ), zirconium oxide (ZrO ₂ ), beryllium oxide (BeO), thorium oxide (ThO ₂ ), PL
ZT-based, ferrite-based, chalcogen-based, oxide glass-based, rare earth-cobalt-based, and polyphase ceramics thereof are included. Further, a non-oxide type powder that can be treated will be described. Examples of non-oxide type powders include carbon, silicon carbide (SiC) type, titanium carbide (TiC), boron nitride (BN), cadmium sulfide (CdS) and These multi-phase ceramics are included. When cement is described as a powder that can be treated, the cement includes Portland cement, magnesia cement, alumina cement, silica cement and the like.

Next, the above-mentioned powder is weighed in an appropriate amount, the upper container 1b of the reaction container 1 is removed, and the lower container 1a of the reaction container 1 is loaded or introduced into the lower container 1a. Then, the upper container 1b is joined to the lower container 1a with the clamp 3.

The required gas is supplied to the rare gas supply pipe 10,
By introducing the gas into the reaction vessel 1 through the other gas supply pipe 13 and / or the monomer gas supply pipe 14 and applying a voltage to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9,
Atmospheric pressure plasma treatment was performed. The first processing method will be described below. 2 [g] of the treated silica powder was loaded into the reaction container 1, and 2000 [ml] of a rare gas (helium (He)) was supplied into the reaction container 1 through the rare gas supply pipe 10. Then, a voltage is applied to the ground electrode 7, the high-voltage applying electrode 8 and the ground electrode 9 to perform atmospheric pressure plasma treatment 1
It went for 0 minutes. At this time, PE is used as a dielectric for the ground electrode 7, the high-voltage applying electrode 8, etc.
The high voltage application electrode 8 and the ground electrode 9 have a frequency of 23 [kHz].
Was applied. At this time, the discharge start power is 1
It was 50 [W].

The results of the atmospheric pressure plasma treatment as described above were evaluated as follows. Regarding the evaluation of dispersibility, 0.2 [g] of the treated silica powder was sampled in a dispersion bottle, 20.0 [ml] of distilled water was added, and the dispersion was performed with a paint saker. With respect to the dispersion and sedimentation speed with respect to the solvent, 0.2 [g] of the treated silica powder was sampled in a dispersion bottle, and 20.0 [ml] of MEK (methyl ethyl ketone) was added and dispersed with a paint-saker. .. After the media was not added and the dispersion time was 10 minutes, a part of the dispersion was sampled, placed in a quartz cell, and the sedimentation rate was measured by an ultraviolet and visible spectrophotometer. Vehicles with good dispersion showed a relatively low pigment settling rate and low transmittance. When the sedimentation speed is high, the supernatant liquid increases the transmittance with the passage of time, so the transmittance was measured with the passage of time, and was set as the sedimentation rate. Depending on the particle size and specific gravity of the powder,
Since the transmittance changes, a relative comparison was made between the same powders. The transmittance varies depending on the type of pigment, solvent, etc., but after setting, the transmittance was measured every 9 minutes, 30 minutes, and 90 minutes. The transmittance value is a value at a wavelength of 700 [millimicron] at each time.

Regarding the cohesiveness, the cohesiveness of the powder in the dispersion was observed after sedimentation. Regarding redispersibility, the redispersibility was observed after shaking the dispersion after sedimentation. Similar dispersion is applied to untreated silica powder,
The measurement was performed. Regarding the blendability, the untreated powder and the treated powder were weighed by 0.5 [g], and the acrytonitrile rubber solution (solid portion 20 [%] ME
K solution) was mixed with 10 [g] and the particle size was measured with a grind gauge. Helium (H
e) The treated product showed good dispersibility, redispersibility, cohesiveness, and kneading property in an aqueous dispersion system. The evaluation and processing conditions described above are shown in Table 1.

[Table 1] In Table 1, kneading evaluation criteria (dispersed particle diameter [μ] Hegman gauge) are 5 for ⊚, 5 to 10 for ○, and Δ for
10 to 15 and x are described on the basis of 15 to 25. In addition,
The same applies to the tables below.

Next, the second processing method will be described. Silica powder was loaded into the reaction vessel 1 in the same manner as in the first treatment method, and 2000 [ml] of a rare gas (He) was introduced into the reaction vessel 1 through the rare gas supply pipe 10. , 2000 [ml] of monomer gas (CF ₄ ) per minute is introduced into the reaction vessel 1 through the monomer gas supply pipe 14, and voltage is applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9. Then, the atmospheric pressure plasma treatment was performed for 10 minutes. At this time, PE was used as a dielectric for the ground electrode 7, the high voltage applying electrode 8 and the like, and an AC voltage having a frequency of 25 [kHz] was applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9. .. At this time, the discharge start power is 150 [W]
Met. The results of the atmospheric pressure plasma treatment as described above were evaluated as follows, and the results are shown in Table 2. Of course, Table 2 also describes processing conditions. The treated silica powder 0.2 [g] was weighed in a dispersion bottle, distilled water and MEK 2 0.0 [ml] were added, and the dispersion was evaluated in the same manner as in the first treatment method. As can be seen from Table 2, in the case of the CF ₄ treated silica powder, contrary to the first treatment method, improvement in dispersibility in solvent and MEK, redispersibility, cohesiveness and kneading property was observed. ..

[Table 2]

Further, the third processing method will be described below. Silica powder was loaded into the reaction vessel 1 in the same manner as in the first treatment method, and 2000 [ml] of rare gas (H 2
e) is introduced into the reaction container 1 through the rare gas supply pipe 10, and formic acid is introduced as another gas into the reaction container through the other gas supply pipe 13 by a bubbling method. A voltage was applied to the application electrode 8 and the ground electrode 9 to perform atmospheric pressure plasma treatment for 10 minutes. At this time,
As the dielectrics of the ground electrode 7, the high voltage applying electrode 8 and the like, those in which a liquid dielectric 20 is enclosed in a glass container 19 are used, and the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9 are used.
An alternating voltage having a frequency of 28 [kHz] was applied to. At this time, the discharge start power was 75 [W]. The results of the atmospheric pressure plasma treatment as described above were evaluated as follows, and the results are shown in Table 3. Of course, Table 3 also describes processing conditions. Similar to the first method, the results of dispersion with distilled water and MEK show that, as can be seen from Table 3, in MEK, dispersibility, redispersibility,
Improvements in cohesiveness and blendability were observed.

[Table 3]

As shown in FIG. 3, the ground electrode 7 or the high voltage applying electrode 8 uses aluminum as the metal electrode 17, and GE as the liquid dielectric 20 in the glass tube 19.
When a plasma discharge was performed using a silicone oil (SF96-100) manufactured by the same company, a uniform glow discharge was stably obtained. Further, the power applied to the ground electrode 7, the high voltage applying electrode 8 and the like is increased to 200 [W],
When a continuous treatment for 30 minutes was tried, a stable glow discharge was maintained. After the discharge was completed, the ground electrode 7, the high voltage applying electrode 8 and the like did not generate heat, and thus it was found that the liquid dielectric had a cooling effect. Therefore, in the case of high-power plasma processing, by using the liquid dielectric, it becomes possible to continuously cool the liquid dielectric itself with the circulation cooling device, and thus it is possible to prevent the transition to arc discharge. Very convenient. In addition, the ground electrode 7 having the above-described configuration
Alternatively, in the case of the high-voltage applying electrode 8, it is not necessary to bond the solid dielectric and the metal electrode together, and there is no destruction caused by the difference in coefficient of thermal expansion such as metal and glass, and stable glow discharge can be obtained for a long time. I understood.

In addition, the fourth processing method will be described below. Silica powder was loaded into the reaction vessel 1 in the same manner as in the first treatment method, and 2000 [ml] of rare gas (H 2
e) is introduced into the reaction vessel 1 through the rare gas supply pipe 10, and a 1% aqueous solution of fluorocarbon (FC ₄₃₁ manufactured by 3M) is bubbled (6 mml / min) with He gas as another gas to supply the other gas. It was introduced into the reaction vessel through the tube 13, and a voltage was applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9, and atmospheric pressure plasma treatment was performed for 10 minutes. At this time, PE was used as a dielectric material for the ground electrode 7, the high voltage applying electrode 8 and the like, and an AC voltage having a frequency of 24 [kHz] was applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9. .. At this time, the discharge start power is 75
It was [W]. The results of the atmospheric pressure plasma treatment as described above were evaluated as follows, and the results are shown in Table 4. Of course, Table 4 also describes the processing conditions. Distilled water, MEK as in the first method
As can be seen from Table 3, the results of dispersion by MEK showed improvement in dispersibility, redispersibility, cohesiveness, and kneading property in MEK. The treated silica powder was dispersed and measured with distilled water and MEK in the same manner as in Example-1. As can be seen from Table 4, improvement in dispersibility, redispersibility, cohesiveness and brittleness was observed with respect to MEK.

[Table 4]

The fifth processing method will be described below. 2 [g] of carbon black powder was loaded into the reaction vessel 1 in the same manner as in the first treatment method described above, and 2000 g / min.
[Ml] rare gas (He) is introduced into the reaction vessel 1 through the rare gas supply pipe 10, and a voltage is applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9 to perform atmospheric pressure plasma. The treatment was carried out for 10 minutes. At this time, PE is used as a dielectric material for the ground electrode 7, the high voltage applying electrode 8 and the like, and the frequency of 22 is applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9.
An alternating voltage of [kHz] was applied. At this time, the discharge start power was 75 [W]. 0.2 g of the carbon black powder thus treated was collected in a dispersion bottle, 20.0 ml of distilled water was added, and 1 with a paint-saker.
Dispersed for 0 minutes. Hereafter, it measured similarly to the 1st processing method. At the same time, the untreated carbon black was similarly compared and compared. The measurement results are shown in Table 5. As can be seen from Table 5, the He-treated carbon black was found to have remarkably improved dispersibility, redispersibility, cohesiveness, and brittleness as compared with untreated carbon black.

[Table 5]

Further, the sixth processing method will be described below. In the same manner as in the first treatment method, 2 [g] of carbon black powder was loaded into the reaction vessel 1 and the reaction was performed at 200 minutes per minute.
0 [ml] of rare gas (He) is introduced into the reaction vessel 1 via the rare gas supply pipe 10, and methanol as another gas is bubbled with He gas (6 ml / min) to supply the other gas supply pipe 13. Was introduced into the reaction vessel via the, and a voltage was applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9, and atmospheric pressure plasma treatment was performed for 10 minutes. At this time,
PE was used as a dielectric material for the ground electrode 7, the high voltage applying electrode 8 and the like, and an AC voltage having a frequency of 22 [kHz] was applied to the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9. At this time, the discharge start power was 75 [W]. The processing conditions and the processing results are shown in Table 6. The treated carbon black powder 0.2 [g] was sampled in a dispersion bottle, distilled water 20.0 [ml] was added, and the mixture was dispersed for 10 minutes with a paint saker. Hereinafter, the measurement was performed in the same manner as the first treatment method.
As a result, as can be seen from Table 6, improvement in dispersibility, redispersibility, cohesiveness and brittleness was observed with respect to the carbon black powder.

[Table 6]

Finally, the seventh processing method will be described below. 2 [g] of apatite powder was loaded into the reaction vessel 1 in the same manner as in the first treatment method described above, and 2000 [m] / min.
l] of the rare gas (He) is introduced into the reaction vessel 1 through the rare gas supply pipe 10 and at the same time, formic acid is added as H 2
Bubbling with e gas (6 ml / min) is introduced into the reaction vessel 1 through the other gas supply pipe 13, and the ground electrode 7,
A voltage was applied to the high voltage applying electrode 8 and the ground electrode 9, and atmospheric pressure plasma treatment was performed for 10 minutes. At this time, glass is used as a dielectric for the ground electrode 7, the high voltage applying electrode 8 and the like, and the ground electrode 7, the high voltage applying electrode 8 and the ground electrode 9 are used.
An alternating voltage having a frequency of 24 [kHz] was applied to. At this time, the discharge start power was 75 [W]. The processing conditions and the processing results are shown in Table 6. As can be seen from Table 6, the formic acid-treated apatite was found to have improved dispersibility, redispersibility, cohesiveness, and kneading property in MEK dispersion. The untreated apatite powder was also evaluated in Table 7.
Described in.

[Table 7]

As described above, the processing method for the typical powder, rare gas, monomer gas, and other gas is explained, and the evaluation of the processing result is also explained, and the results are shown in each table. .. As described above, in the above embodiment,
By changing the processing gas depending on the type of powder,
It becomes possible to improve dispersibility, redispersibility, cohesiveness and brittleness in both water-based and solvent-based systems. this is,
By applying the invention, it is possible to disperse what could not be dispersed conventionally by dispersing the conventional powder, and it is possible to improve the solubility depending on the kind of powder. And that the surface of the powder can be easily modified. Further, by using the liquid dielectric 20 for the ground electrode 7, the high voltage applying electrode 8 and the like, the discharge electrode portion can be easily expanded and the manufacturing cost can be reduced. Moreover, the combined use of the circulation cooling device makes it possible to control the temperature of the discharge electrode portion even during continuous treatment for a long time, so that stable discharge can be sustained, and it can be expected that the range of application will be further expanded.

[0038]

As described above, according to the first and second aspects of the present invention, by changing the processing gas depending on the kind of powder, dispersibility in both water-based and solvent-based systems, It is possible to obtain a powder having improved redispersibility, cohesiveness and kneading property, and it is possible to easily modify the surface of the powder.

Further, according to the invention of claim 6, the processing gas can be changed depending on the kind of the powder, and the dispersibility, redispersibility and aggregation in both the water system and the solvent system can be obtained. There is an effect that it is possible to realize a method for obtaining powder having improved properties and blendability.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an atmospheric pressure plasma reactor of the present invention.

FIG. 2 is a diagram showing a configuration example of a ground electrode and a high voltage applying electrode used in the same embodiment.

FIG. 3 is a diagram showing another configuration example of the ground electrode and the high voltage applying electrode used in the same embodiment.

[Explanation of symbols]

 1 Reaction Vessel 1a Lower Vessel 1b Upper Vessel 2 O-ring 3 Clamp 4 Filter 5 Mesh 7 Grounding Electrode 8 High Voltage Application Electrode 9 Grounding Electrode 10 Rare Gas Supply Pipe 13 Other Gas Supply Pipe 14 Monomer Gas Supply Pipe 17 Metal Electrode 18 Dielectric Coating material 19 Container 20 Liquid dielectric

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000122450 Sachiko Okazaki 2-20-11 Takaido East, Suginami-ku, Tokyo (71) Applicant 390035932 Masuhiro Ogoma 843-15 Shimoshinkura, Wako-shi, Saitama (72) Inventor Tani Previous Tatsuzo 247 Kou Urasaki-cho, Onomichi, Hiroshima Prefecture (72) Inventor Sachiko Okazaki 2-20-11 Takaido Higashi, Suginami-ku, Tokyo (72) Inventor Masuhiro Ogoma 843-15 Shimoshinkura, Wako-shi, Saitama

Claims (7)

[Claims] 1. A powder is placed in a reaction vessel composed of a high voltage applying electrode and a ground electrode, which is formed by covering a metal electrode with a dielectric, and a rare gas and a monomer gas are introduced individually or in a mixed manner, A method of utilizing an atmospheric pressure plasma reaction, characterized in that the powder surface is treated by supplying electric power to a high voltage applying electrode and a ground electrode to excite plasma under atmospheric pressure. 2. A powder is placed in a reaction vessel composed of a high voltage applying electrode and a ground electrode, in which a metal electrode is covered with a dielectric, and a rare gas and a monomer gas are introduced individually or in a mixed manner, and A method of utilizing an atmospheric pressure plasma reaction, characterized in that another gas is introduced and electric power is supplied to the high voltage applying electrode and the ground electrode to excite plasma under atmospheric pressure to treat the powder surface. 3. The method of utilizing an atmospheric pressure plasma reaction according to claim 2, wherein the other gas is a solvent gas. 4. The method of utilizing an atmospheric pressure plasma reaction according to claim 2, wherein the other gas is a gas of an organic acid or an inorganic acid, a complex gas thereof, or an alkaline gas. 5. The method of utilizing the atmospheric pressure plasma reaction according to claim 2, wherein the other gas is a surfactant-containing solution aerosol. 6. A reaction container for causing an atmospheric pressure plasma reaction, a high-voltage applying electrode and a ground electrode which are provided at least inside the reaction container and are formed by covering a metal electrode with a dielectric, and the reaction container. A rare gas supply pipe for introducing a rare gas inside, a monomer gas supply pipe for introducing a monomer gas inside the reaction container, another gas supply pipe for introducing another gas inside the reaction container, and the reaction An atmospheric pressure plasma reactor comprising: an exhaust gas pipe for discharging a constant gas from a container. 7. The atmospheric plasma reactor according to claim 6, wherein a liquid dielectric is used alone or in combination with a solid dielectric as the dielectric material of the high voltage applying electrode and the ground electrode. ..