Granted Patent
Utility
US 5,417,751 · App. 08/144,237
Heat cured foundry binders and their use
Inventors:
Helena Twardowska, Heimo J. Langer
Patented Case
View Patent ↗
Granted: May 23, 1995
Filed: Oct 27, 1993
Inventors
Helena Twardowska
Heimo J. Langer
Assignee (at issue)
Ashland Oil, 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.