Granted Patent
Utility
US 4,806,390 · App. 07/108,430
Masking compositions for chemical milling and method for applying the same
Inventors:
Fred D. Hawker, Victor E. Pietryga, Robert W. Byrd
Patented Case
View Patent ↗
Granted: Feb 21, 1989
Filed: Oct 14, 1987
Inventors
Fred D. Hawker
Victor E. Pietryga
Robert W. Byrd
Assignee (at issue)
DeSoto, Inc.
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.