Granted Patent
Utility
US 5,911,269 · App. 08/716,955
Method of making silica sand molds and cores for metal founding
Inventors:
John J. Brander, Ronald M. Kotschi
Patented Case
View Patent ↗
Granted: Jun 15, 1999
Filed: Sep 20, 1996
Inventors
John J. Brander
Ronald M. Kotschi
Assignee (at issue)
Industrial Gypsum Co., 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.