Granted Patent
Utility
US 4,436,893 · App. 06/436,228
Copolyester of polyethylene terephthalate and sulfonyl diphenol
Inventor:
Michael S. Cholod
Patented Case
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Granted: Mar 13, 1984
Filed: Oct 25, 1982
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.