Granted Patent
Utility
US 4,500,657 · App. 06/509,770
Dental restorative compositions having improved mechanical properties and hydrolytic stability
Inventor:
Narayan Kumar
Patented Case
View Patent ↗
Granted: Feb 19, 1985
Filed: Jul 1, 1983
Inventor
Narayan Kumar
Assignee (at issue)
Johnson & Johnson Dental Products 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.