Granted Patent
Utility
US 4,547,563 · App. 06/558,083
Copolyester of polyethylene terephthalate and bis (4-beta hydroxy ethoxy phenyl) sulfone
Inventor:
Michael S. Cholod
Patented Case
View Patent ↗
Granted: Oct 15, 1985
Filed: Dec 5, 1983
Inventor
Michael S. Cholod
Assignee (at issue)
Rohm and Haas Company
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.