Granted Patent
Utility
US 5,362,817 · App. 08/108,862
Polyisobutylene based block copolymers
Inventor:
Akhtar Osman
Patented Case
View Patent ↗
Granted: Nov 8, 1994
Filed: Aug 18, 1993
Inventor
Akhtar Osman
Assignee (at issue)
Polysar Rubber Corporation
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.