Granted Patent
Utility
US 4,994,548 · App. 07/509,839
Modified bisphenol resins having at least one arylcyclo-butanenealkyl moiety
Inventor:
Pui K. Wong
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: Apr 17, 1990
Inventor
Pui K. Wong
Assignee (at issue)
SHELL OIL COMPANY
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.