Granted Patent
Utility
US 4,696,991 · App. 06/893,822
Blocked polyisocyanurate
Inventors:
Yoshimichi Kobayashi, Hisaharu Hotta
Patented Case
View Patent ↗
Granted: Sep 29, 1987
Filed: Aug 6, 1986
Inventors
Yoshimichi Kobayashi
Hisaharu Hotta
Assignee (at issue)
Mitsubishi Chemical 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.