Granted Patent
Utility
US 4,872,995 · App. 07/203,035
Method for calcium oxalate scale control
Inventors:
Fu Chen, Daniel L. Michalopoulos
Patented Case
View Patent ↗
Granted: Oct 10, 1989
Filed: Jun 6, 1988
Inventors
Fu Chen
Daniel L. Michalopoulos
Assignee (at issue)
Betz Laboratories, 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.