Granted Patent
Utility
US 4,980,382 · App. 07/519,037
Process for the preparation of expandable vinyl aromatic polymer particles containing hexabromocyclododecane
Inventors:
Fred Sonnenberg, Dennis M. Hajnik
Patented Case
View Patent ↗
Granted: Dec 25, 1990
Filed: May 4, 1990
Inventors
Fred Sonnenberg
Dennis M. Hajnik
Assignee (at issue)
Arco Chemical Technology, L.P.
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.