Granted Patent
Utility
US 4,870,114 · App. 06/824,548
Heat-foamable crosslinked propylene resin composition in the form of a melt-shaped sheet structure
Inventors:
Takashi Hashimoto, Zenichi Sasaki
Patented Case
View Patent ↗
Granted: Sep 26, 1989
Filed: Jan 23, 1986
Inventors
Takashi Hashimoto
Zenichi Sasaki
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.