Granted Patent
Utility
US 6,008,313 · App. 08/974,284
Polyamide curing agents based on mixtures of polyethyleneamines and piperazine derivatives
Inventors:
Frederick Herbert Walker, William E. Starner, Andrea Karen Smith
Patented Case
View Patent ↗
Granted: Dec 28, 1999
Filed: Nov 19, 1997
Inventors
Frederick Herbert Walker
William E. Starner
Andrea Karen Smith
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.