Granted Patent
Utility
US 4,842,756 · App. 07/028,850
Multifunctional viscosity index improver
Inventors:
Christopher S. Liu, Maria M. Kapuscinski, Larry D. Grina, Ronald E. Jones
Patented Case
View Patent ↗
Granted: Jun 27, 1989
Filed: Mar 23, 1987
Inventors
Christopher S. Liu
Maria M. Kapuscinski
Larry D. Grina
Ronald E. Jones
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.