IP Library › Granted Patent US 4,980,144
Granted Patent Utility
US 4,980,144 · App. 07/356,179

Process for purifying nitrogen trifluoride gas

Inventors: Nobuhiko Koto, Toshihiko Nishitsuji, Naruyuki Iwanaga, Isao Harada
Patented Case View Patent ↗
Granted: Dec 25, 1990 Filed: May 24, 1989
Inventors
Nobuhiko Koto
Toshihiko Nishitsuji
Naruyuki Iwanaga
Isao Harada
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated

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Quick Facts
Patent No.
US 4,980,144
App. No.
07/356,179
Filed
1989-05-24
Granted
1990-12-25
Kind
A