Granted Patent
Utility
US 6,211,135 · App. 09/283,448
Processes for the purification and use of 2,2-dichloro-1,1,1,3,3,3-hexafluoropropane and azeotropes thereof with HF
Inventors:
Ralph Newton Miller, V. N. Mallikarjuna Rao, Steven H. Swearingen
Patented Case
View Patent ↗
Granted: Apr 3, 2001
Filed: Apr 1, 1999
Inventors
Ralph Newton Miller
V. N. Mallikarjuna Rao
Steven H. Swearingen
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND 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.