Granted Patent
Utility
US 5,314,632 · App. 07/894,390
Combining dispersant viscosity index improver and detergent additives for lubricants
Inventors:
Brian L. Papke, Issac D. Rubin, John Castrogiovanni, Jr.
Patented Case
View Patent ↗
Granted: May 24, 1994
Filed: Jun 5, 1992
Inventors
Brian L. Papke
Issac D. Rubin
John Castrogiovanni, Jr.
Assignee (at issue)
Texaco 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.