J. Inst. Electrostat. Jpn.

, 32, 2 (2008) 90 91ᄢ᳇࿶ࠦࡠ࠽᡼㔚ࡊ࡜࠭ࡑࠫࠚ࠶࠻ࠍ↪޿ߚᲕ⩶ⵝ⟎ศ↰ᕺ৻㇢㧖,㧝㧘ᣣᲧ㊁೑෹㧖㧖㧘૒ષ⊓㧖㧖㧖,㧞㧘ᄢਭ଻㓷┨㧖㧖,㧟㧔2008 ᐕ 1 ᦬ 30 ᣣฃઃ; 2008 ᐕ 3 ᦬ 24 ᣣฃℂ㧕Sterilization Device Using Corona Discharge Plasma Jet at Atmospheric Pressure
Keiichiro YOSHIDA,㧖, 1 Toshitomo HIBINO,㧖㧖Noboru SAEKI㧖㧖㧖, 2 and Masaaki OKUBO㧖㧖, 3(Received January 30, 2008; Accepted March 24, 2008)
Sterilization using atmospheric pressure corona discharge plasma jet is successfully carried out. The plasma jet isapplied for 0 ~ 5 s to several pieces of test paper including bacteria (Escherichia coli or Saccharomyces cerevisia).
After the application of the nonthermal plasma jet, the bacteria are cultured in an incubator. The number of colonies on
the test pieces is counted. It is known from this test that exposure time of 1s is enough for more than 88% reduction ofboth the bacteria. Complete deactivation is performed with the exposure time of 5 s for both the bacteria.

1.

⺞㜞㔚࿶ࠍශടߒ㧘ࠦࡠ࠽᡼㔚ߣㅍ㘑ᯏߦࠃߞߡ㕖ᾲࡊ࡜ߪߓ߼ߦ㘩ຠ⣣ᢌ㒐ᱛ߿ක≮ᣉ⸳ߢᗵᨴ∝㒐ᱛߦ↪޿ࠄࠇߡ޿ࠆ1)࠭ࡑྃᵹࠍ⊒↢ߐߖࠆ㧚᷷ࠟࠬᐲߪ 50 °C એਅߢ޽ࠆ㧚ߎᲕ⩶ᴺߦ㧘ടᾲಣℂ㧘᡼኿✢ᾖ኿㧘⮎೷ಣℂߥߤ߇޽ࠆ 㧚ߩࡊ࡜࠭ࡑྃᵹ߇⩶ࠍ฽߻⹜㛎ߦᾖ኿ߐࠇᲕ⩶߇ታ⃻ߒ߆ߒ㧘ᾲߦࠃࠆᲕ⩶ߢߪᄙ㊂ߩࠛࡀ࡞ࠡ࡯ࠍᔅⷐߣߔࠆߔࠆ㧚ࡊ࡜࠭ࡑ࠻࡯࠴వ┵ߣ⹜㛎ߩ〒㔌ߪ 20 mm㧘ⓨ᳇਄㧘㘩ຠߦㆡ↪ߒߚ႐วߦߪ࠲ࡦࡄࠢ⾰ߩᄌᕈߦࠃࠆ๧ߩ

ᵹ㊂ߪ 40㨪50 L/min㧘࠻࡯࠴వ┵ߩᵹㅦ 7 m/s ߢ޽ࠅ㧘⹜ૐਅߩ໧㗴߇޽ࠆ㧚߹ߚ㧘᡼኿✢ಣℂߢߪㆤ߳޿ߩᔅⷐᕈ㧘㛎ߪ 25 °C㧘⋧ኻḨᐲ 70%ߩ⹜㛎ቶߢⴕߞߚ㧚⮎೷ಣℂߢߪᲥᕈߩ໧㗴߇޽ࠆ㧚ᧄ⎇ⓥߢߪ⋭ࠛࡀ࡞ࠡ࡯

࿑ 2 ߦ㕖ᾲࡊ࡜࠭ࡑ⊒↢ⵝ⟎ߩ㔚ሶ࿁〝ࠍ␜ߔ㧚໡↪

ߢ◲ᤃߥᣂߒ޿ૐ᷷Ვ⩶ᴺߣߒߡ㧘ᄢ᳇࿶ⓨ᳇ࠦࡠ࠽᡼㔚

AC100 V ࠍ㔚Ḯߣߒ㧘20 kHz㧘ᦨᄢࡇ࡯ࠢ㑆㔚࿶ 24 kV ߩߦࠃࠅ⊒↢ߔࠆ㕖ᾲࡊ࡜࠭ࡑྃᵹࠍ↪޿ߚᣇᴺߣⵝ⟎ࠍ੤ᵹ㜞㔚࿶߇᡼㔚㔚ᭂߦශടߐࠇࠆ㧚߹ߚ㧘࿑ਛ D ㇱߢឭ᩺ߒ㧘ᄢ⣺⩶ߣ㉂Უ㧔⌀⩶㧕ߦኻߔࠆᲕ⩶⹜㛎ࠍⴕ޿㧘

IGBT㧔Insulated Gate Bipolar Transistor㧕ߦࠃࠆࡄ࡞ࠬᄌ⺞᦭ലߥ⚿ᨐࠍᓧߚߩߢႎ๔ߔࠆ㧚㧔ᄌ⺞๟ᵄᢙ 60 Hz㧕ߦࠃߞߡශട㜞㔚࿶ߩ࠺ࡘ࡯࠹ࠖᲧ

2.

⹜㛎ⵝ⟎ߣ⹜㛎ᣇᴺࠍᄌᦝߒ㧘᡼㔚಴ജࠍ⺞▵ߔࠆ㧚ᧄ⹜㛎ߢߪ㧘ࡇ࡯ࠢ㑆㔚࿑ 1 ߦ⹜㛎ⵝ⟎ߩ᭎⇛ࠍ␜ߔ㧚ᄖ᳇ࠍขࠅ౉ࠇࠆㅍ㘑ᯏ2)

࿶ 24 kV㧘࠺ࡘ࡯࠹ࠖᲧ 50%ߣߒߚ㧚ࠍᲕᄢ⣺⩶㧔Escherichia coli㧕ߩᲕ⩶⹜㛎ߦߪᄢ⣺⩶⟲⹜㛎⩶ߦ↪޿ࠆ㧚৻ኻߩࡢࠗࡗ⁁᡼㔚㔚ᭂߦ㜞㔚࿶⊒↢ⵝ⟎⚕㧔SIBATA CODE8051-301㧘ᩊ↰⑼ቇࢃ⵾㧕ࠍ↪޿ߚ㧚⹜

㧔Plasma stream PSC1002㧘ࡄ࡯࡞Ꮏᬺࢃ⵾㧕ߦߡࡄ࡞ࠬᄌ

㛎⚕ߩᄢ߈ߐߪ 20×100 mm ߢ޽ࠆ㧚ᄢ⣺⩶ࠍ฽߻ᑄ᳓ߦࠠ࡯ࡢ࡯࠼㧦ࠦࡠ࠽᡼㔚㧘Ვ⩶㧘㕖ᾲࡊ࡜࠭ࡑ㧘ᄢ⣺⩶㧘㉂Უ
* JST ࠗࡁࡌ࡯࡚ࠪࡦࡊ࡜ࠩᄢ㒋㧔594-1144 ๺ᴰᏒ࠹ࠢ
ࡁࠬ࠹࡯ࠫ 3-1-10㧕JST Innovation Plaza Osaka, 3-1-10,Techno-Stage, Izumi, Osaka, 594-1144, Japan** ᄢ㒋ᐭ┙ᄢቇᄢቇ㒮Ꮏቇ⎇ⓥ⑼ᯏ᪾♽ኾ᡹㧔599-8531
႓ Ꮢ ਛ ඙ ቇ ࿦ ↸ 1-1 㧕 Department of MechanicalEngineering, Osaka Prefecture University, 1-1 Gakuen-cho,Naka-ku, Sakai 599-8531, Japan*** ࡄ࡯࡞Ꮏᬺࢃ㧔559-0015 ᄢ㒋Ꮢ૑ਯᳯ඙ධട⾐ደ
3-8-13㧕Pearl Kogyo Co., Ltd., 3-8-13 Minamikagaya,
Suminoe-ku, Osaka 559-0015, Japan
1yoshida@osaka.jst-plaza.jp
2n_saeki@pearl-kg.co.jp
3
mokubo@me.osakafu-u.ac.jp

࿑ 1 Ვ⩶⹜㛎ⵝ⟎ߩ᭎⇛
Fig. 1 Schematics of experimental device for sterilization.

ࠍౝ⬿ߒ㧘వ┵ㇱߦ᡼㔚㔚ᭂࠍᜬߟࡊ࡜࠭ࡑ࠻࡯࠴

91 (35)ߦኻߒ㧘⩶ࠍၭ㙃$& 9㛎⚕ࠍࠗࡦࠠࡘࡌ࡯࠲ౝߦ 37 °C ߢ 15 h ᡼⟎ߒ㧘⩶ࠍၭ㙃㪂㪂䌎䊶䌆㧚ฦ‫⹜ߩޘ‬*DWHVLJQDO RI
EXV FRQWURO,*%7JDWH
GULYH XQLW3ODVPD࡯ᒻᚑߦࠃଔߔࠆ㧚↰⑼ቇࢃ⵾㧕ࠍ↪޿ߚ㧚߹ߕ㧘࠼࡜ࠗࠗ࡯ࠬ࠻ 6 g ߣ⍾♧
15 g ࠍ⫳⇐᳓ 500 mL ߦ౉ࠇ 30 °C ߢ 60 min 㑆⊒㉂ߐߖࠆ㧚ߎߩᶧߦ⹜㛎⚕ࠍ 6 ᨎᶐߒ㧘⹜㛎

࿑2㕖ᾲࡊ࡜࠭ࡑ⊒↢ⵝ⟎ߩ㔚ሶ࿁〝㧔PSC1002㧘ࡄ࡯࡞Ꮏᬺࢃ㧕
Fig. 2 Electric circuit of the nonthermal plasma generator(PSC1002, Pearl Kogyo, Co., Ltd.).

㧚߹ߚ㧘ࡊ࡜ߥߞߚ㧚ߪ㧘ࡊ࡜࠭ࠅᢙ߃ࠆߎߢߪ㧘ࠦࡠ

1XPEHURIFRORQLHV୘ߢ޽ߞߚ

ߒߡ޿ࠆ㧚߹

⷗ࠄࠇߥߊߡߪ㧘ක≮↪

ฦ⒳ᵴᕈ⒳

0s



1s

2s

3s4s



ߣ߇ߢ߈ߚ㧚ߦ㧘ࡊ࡜࠭ߣṌ⩶ߩࠟ

amoto: Thin

Appl. Phys.

߇㧘1 s 㑆ࡊ࡜࠭ࡑࠍᾖ኿ߒߚ⹜㛎ߢߪ 3 ୘ߣߥࠅ㧘88%ߢߪᭂ߼ߡᄙᢙߢ޽ࠅᢙ߃ࠆߎߣ߇ߢ߈ߥ޿㧚ߒ߆ߒ㧘ᾖ኿ᤨ㑆 1 s ߩ⹜㛎࠾࡯ᢙߪ 1 ୘ߣߥࠅᄢㇱಽߩࠦࡠ࠾࡯߇ᶖṌߒߡ޿ࠆ㧚߹

0s࠴ࡘ࡯ࡉౝߩᲕ⩶ߦ߅޿ߡ㕖ᾲࡊ࡜࠭ࡑਛߩฦ⒳ᵴᕈ⒳߿⚡ᄖ✢ߩലᨐ߇੍᷹ߐࠇߡ޿ࠆ 3)㧚ᧄ⹜㛎ߦ߅޿ߡ߽㘃

2s3s4s5s߇޽ࠆ㧚ᄢ᳇࿶ⓨ᳇ࠦࡠ࠽᡼㔚ߦࠃࠅ⊒↢ߔࠆ㕖ᾲࡊ࡜࠭ࡑྃ߅ࠊࠅߦᵹࠍኻ⽎ߦᾖ኿ߔࠆߣ޿߁◲ᤃߥᚻᴺߦࠃࠅ㧘ᭂ߼ߡ⍴ᤨ㑆ߢᄢ⣺⩶߅ࠃ߮㉂Უߩ⩶ᢙࠍᷫዋߐߖࠆߎߣ߇ߢ߈ߚ㧚੹ᓟ㧘ᧄࡊ࡜࠭ࡑᲕ⩶ⵝ⟎ߩታ↪ൻࠍ࿑ࠆߣ౒ߦ㧘ࡊ࡜࠭ࡑⵝ⟎ߩᔕ↪▸࿐ࠍᮨ⚝ߒߡ޿ߊ㧚

4.

㉄߳ߩᓇ㗀ࠍ⹏ଔߒ㧘Ვ⩶ߩᯏ᭴ࠍ᣿ࠄ߆ߦߒߡ޿ߊᔅⷐ

࿑3Fig. 3ૃߩ૞↪߇ሽ࿷ߔࠆߣ⠨߃ࠄࠇࠆ߇㧘ߎࠇࠄߩ⚦⢩⤑߿ᩭ1sߚ㧘3 s એ਄ࡊ࡜࠭ࡑࠍᾖ኿ߔࠆߣࠦࡠ࠾࡯ߪ⷗ࠄࠇߥߊ
Ვ⩶ࠍᒁ߈⿠ߎߔ㕖ᾲࡊ࡜࠭ࡑߩ૞↪ߣߒߡߪ㧘ක≮↪

([WUHPHO\ODUJHߢߪ㧘ࠦࡠߥߞߚ㧚࿑ 3 ᄢ⣺⩶ߩᲕ⩶⹜㛎⚿ᨐ
Fig. 3 Sterilization of Escherichia coli.

1XPEHURIFRORQLHV㧘ᭂ߼ߡ⍴ᤨ

ߢߪ 27 ୘ߢ޽ߞߚ

3ODVPDDSSO\LQJWLPH Vߡ޿ߊᔅⷐᢙߪ㧘ࡊ࡜࠭ࡑᾖ኿ߒߡ޿ߥ޿⹜㛎ࡑᾖ኿ߒߡ޿ߥ޿⹜㛎



Fig.

⹜㛎⚿ᨐߣ⠨ኤ࿑ 4 ߦ㉂Უߦኻߔࠆ⚿ᨐࠍ␜ߔ㧚ࠦࡠ࠾࡯ᢙߪ㧘ࡊ࡜࠭߅޿ߡ߽㘃ࡊ࡜࠭ࡑྃࠆ⹜㛎⚕ߩ⊒⦡ㇱ૏ᢙࠍᢙ߃ߡᲕ⩶ലᨐࠍ⹏ଔߔࠆ㧚࠭ࡑࠍ 5 s 㑆ᾖ኿ߔࠆߣࠦࡠ࠾࡯ߪ⷗ࠄࠇߥߊߥߞߚ㧚࿑2㙃ߔࠆ㧚ߘߩᓟ㧘ᄢ⣺⩶ߩ႐วߣห᭽ߦࠦࡠ࠾࡯ᒻᚑߦࠃએ਄ߩࠦࡠ࠾࡯߇ᶖṌߒߡ޿ࠆߎߣ߇ࠊ߆ࠆ㧚߹ߚ㧘ࡊ࡜$'&%3RZ&2X'7UD('LV࿑ 3 ߦᄢ⣺⩶ߦኻߔࠆᲕ⩶⹜㛎ߩ⚿ᨐࠍ␜ߔ㧚ࠦࡠ࠾࡯5s⚦⢩⤑߿ᩭࠍ૞ᚑߔࠆ㧚ฦ‫⹜ߩޘ‬ℂᓟߩ⹜㛎⚕ࠍࠗࡦࠠࡘࡌ࡯࠲ౝߦ 37 °C ߢ 24 h ᡼⟎ߒၭ3.



*DWHFKDߦኻߒ㧘1㨪5 s ߩ㑆ࡊ࡜࠭ࡑᾖ኿ࠍⴕ߁㧚ᧂಣℂߣಣ㛎ߔ㧚ࠦࡠ࠾࡯ߣߥࠅ㧘88%

䌎䊶䌆㉂Უ㧔⌀⩶㧘಴⧘㉂Უ㧦Saccharomyces cerevisiae㧕ߩᲕ⩶⹜㛎ߦߪ㧘৻⥸⚦⩶⹜㛎⚕㧔SIBATA CODE8051-302㧘ᩊ$'&SRZHUVXSSO\%3RZHUIDFWRULPSURYHPHQWFLUFXLW '&9&2XWSXW YROWDJHVHWXS FLUFXLW'&ᨺ9'7UDQVIRUPHUGULYH FLUFXLW ,*%7('LVFKDUJHHOHFWURGHVᧂಣℂߣಣh ᡼⟎ߒၭ&⦡ㇱ૏ᢙࠍᢙ߃ߡᲕ⩶ലᨐࠍ⹏ଔߔࠆߎߣ߇ߢ߈ࠆ㧚*DWHVLJQDO RIFKDUJH SXPSisiae㧕ߩᲕ⊒㉂ߐߖࠆ㧚$ߔࠆ㧚ࠦࡠ࠾࡯߇ᒻᚑߐࠇࠆߣ⹜㛎⚕߇⊒⦡ߔࠆߚ߼㧘⊒ߢ߈ࠆ㧚࠻ 6 g ߣ⍾♧ߦኻߒ㧘1㨪5 s ߩ㑆ࡊ࡜࠭ࡑᾖ኿ࠍⴕ߁㧚ᧂಣℂߣಣℂᓟߩ⹜ࠆߚ߼㧘⊒051-302㧘ᩊࠍ૞ᚑߔࠆ㧚ฦ‫⹜ߩޘ‬㛎

1XPEHURIFRORQLHVಣℂᓟߩ⹜⹜㛎⚕ࠍ 6 ᨎᶐߒ㧘⹜㛎$        %       &      '             (ෳ⠨ᢥ₂1) ዊᨋኯદ㧘ᄢਭ଻ᙗ㧘የኅ㊀ᴦ㧦ᡷ⸓ᶖᲥߣṌ⩶ߩࠟࠗ࠼࡜ࠗࡦ㧘9-14㧘߳ࠆߔ಴ (2005)
2) M. Okubo, M. Tahara, N. Saeki and T. Yamamoto: Thin
Solid Films, (2008) in printing
3) T. Sato, T. Miyahara, A. Doi and S. Ochiai: Appl. Phys.
Lett., 89 (2006) 073902

࿑ 4 ㉂ᲣߩᲕ⩶⹜㛎⚿ᨐ
Fig. 4 Sterilization of Saccharomyces cerevisiae.

2

3ODVPDDSSO\LQJWLPH V

1XPEHURIFRORQLHV⹜㛎࿑4Fig.