Granted Patent
Utility
US 4,990,559 · App. 07/479,288
Thermoplastic resin composition
Inventors:
Takeshi Shiraki, Kunie Hiroshige, Iwatosi Suzuki
Patented Case
View Patent ↗
Granted: Feb 5, 1991
Filed: Feb 13, 1990
Inventors
Takeshi Shiraki
Kunie Hiroshige
Iwatosi Suzuki
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.