Granted Patent
Utility
US 5,125,528 · App. 07/451,812
Container closure, and method for producing same
Inventors:
William M. Heyn, Donald J. Roth
Patented Case
View Patent ↗
Granted: Jun 30, 1992
Filed: Dec 18, 1989
Inventors
William M. Heyn
Donald J. Roth
Assignee (at issue)
Polystar Packaging, Incorporated
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.