Granted Patent
Utility
US 4,849,052 · App. 06/767,257
Batch digester multi-stage pulping process
Inventor:
Ralph S. Grant
Patented Case
View Patent ↗
Granted: Jul 18, 1989
Filed: Aug 21, 1985
Inventor
Ralph S. Grant
Assignee (at issue)
Beloit Corporation
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.