Granted Patent
Utility
US 4,447,646 · App. 06/461,705
Process for the purification of terephthalic acid
Inventors:
Griffin Ivan Johnson, Judy E. Kiefer
Patented Case
View Patent ↗
Granted: May 8, 1984
Filed: Jan 28, 1983
Inventors
Griffin Ivan Johnson
Judy E. Kiefer
Assignee (at issue)
EASTMAN KODAK 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.