Granted Patent
Utility
US 5,409,766 · App. 08/137,354
Nonwoven fabric in an electret state and process for its production
Inventors:
Haruo Yuasa, Masayuki Mito, Yukihiro Takata, Satoshi Matsuura
Patented Case
View Patent ↗
Granted: Apr 25, 1995
Filed: Oct 18, 1993
Inventors
Haruo Yuasa
Masayuki Mito
Yukihiro Takata
Satoshi Matsuura
Assignee (at issue)
Mitsui Petrochemical Industries, Ltd.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.