Granted Patent
Utility
US 5,387,354 · App. 08/003,733
Polyalkylene glycol polycarbonate based lubricant oil composition
Inventors:
Kinya Mizui, Yoshihisa Kiso, Tetsuo Hayashi, Masahide Tanaka
Patented Case
View Patent ↗
Granted: Feb 7, 1995
Filed: Jan 13, 1993
Inventors
Kinya Mizui
Yoshihisa Kiso
Tetsuo Hayashi
Masahide Tanaka
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.