Granted Patent
Utility
US 4,264,803 · App. 05/868,446
Resistance-heated pyrolytic boron nitride coated graphite boat for metal vaporization
Inventor:
Julius S. Shinko
Patented Case
View Patent ↗
Granted: Apr 28, 1981
Filed: Jan 10, 1978
Inventor
Julius S. Shinko
Assignee (at issue)
Union Carbide 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.