Granted Patent
Utility
US 4,966,805 · App. 07/496,011
Heat-shrinkable polystyrene-base foamed composite sheet
Inventors:
Hiroshi Ezawa, Takayuki Watanabe, Hiroaki TSUSHIMA, Zyuzo Nishiba
Patented Case
View Patent ↗
Granted: Oct 30, 1990
Filed: Mar 20, 1990
Inventors
Hiroshi Ezawa
Takayuki Watanabe
Hiroaki TSUSHIMA
Zyuzo Nishiba
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated
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.