Granted Patent
Utility
US 5,620,641 · App. 08/688,215
Polyethylene terephthalate sheath/thermoplastic polymer core bicomponent fibers, method of making same and products formed therefrom
Inventor:
Richard M. Berger
Patented Case
View Patent ↗
Granted: Apr 15, 1997
Filed: Jul 29, 1996
Inventor
Richard M. Berger
Assignee (at issue)
American Filtrona 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.