Granted Patent
Utility
US 4,987,025 · App. 07/222,344
Inflation film of ultrahigh molecular weight polyethylene
Inventors:
Takeshi Shiraki, Koji Nakashima
Patented Case
View Patent ↗
Granted: Jan 22, 1991
Filed: Jul 19, 1988
Inventors
Takeshi Shiraki
Koji Nakashima
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.