Granted Patent
Utility
US 5,221,366 · App. 07/677,918
Etching agents comprising .beta.-diketone and .beta.-ketoimine ligands and a process for using the same
Inventors:
David A. Roberts, John C. Ivankovits, John Anthony Thomas Norman, David A. Bohling
Patented Case
View Patent ↗
Granted: Jun 22, 1993
Filed: Apr 1, 1991
Inventors
David A. Roberts
John C. Ivankovits
John Anthony Thomas Norman
David A. Bohling
Assignee (at issue)
Air Products and Chemicals, 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.