Granted Patent
Utility
US 5,039,780 · App. 07/432,855
Copolyester having gas-barrier property
Inventors:
Mikio Hashimoto, Norio Kaneshige
Patented Case
View Patent ↗
Granted: Aug 13, 1991
Filed: Nov 7, 1989
Inventors
Mikio Hashimoto
Norio Kaneshige
Assignee (at issue)
Mitsui Petrochemical Industries, Ltd.
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.