Granted Patent
Utility
US 4,874,726 · App. 07/121,951
Lightweight fused silica refractory compositions
Inventors:
Thomas R. Kleeb, Berhl E. Wishon
Patented Case
View Patent ↗
Granted: Oct 17, 1989
Filed: Nov 18, 1987
Inventors
Thomas R. Kleeb
Berhl E. Wishon
Assignee (at issue)
Dresser Industries, 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.