Granted Patent
Utility
US 5,041,520 · App. 07/371,072
Process for preparing polyimide having excellent high temperature stability
Inventors:
Masahiro Ohta, Saburo Kawashima, Katsuaki Iiyama, Shoji Tamai, Hideaki Oikawa, Akihiro Yamaguchi
Patented Case
View Patent ↗
Granted: Aug 20, 1991
Filed: Jun 26, 1989
Inventors
Masahiro Ohta
Saburo Kawashima
Katsuaki Iiyama
Shoji Tamai
Hideaki Oikawa
Akihiro Yamaguchi
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated
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.