Granted Patent
Utility
US 6,420,443 · App. 09/393,172
Additives for enhanced hydrocarbon compatibility in rigid polyurethane foam systems
Inventors:
R. Christopher Clark, Brian L. Hilker
Patented Case
View Patent ↗
Granted: Jul 16, 2002
Filed: Sep 9, 1999
Inventors
R. Christopher Clark
Brian L. Hilker
Assignee (at issue)
Crompton 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.