Granted Patent
Utility
US 6,468,939 · App. 09/525,882
Double metal cyanide catalysts for the preparation of polyether polyols
Inventors:
Pieter Ooms, Jörg Hofmann, Pramod Gupta
Patented Case
View Patent ↗
Granted: Oct 22, 2002
Filed: Mar 15, 2000
Inventors
Pieter Ooms
Jörg Hofmann
Pramod Gupta
Assignee (at issue)
Bayer Aktiengesellschaft
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.