Granted Patent
Utility
US 4,731,433 · App. 06/761,900
Aromatic copolyester derived from aromatic dicarboxylic acid component and aromatic diol component
Inventors:
Tadao Yatsu, Takayuki Nakano, Toshiki Sotoyama
Patented Case
View Patent ↗
Granted: Mar 15, 1988
Filed: Aug 2, 1985
Inventors
Tadao Yatsu
Takayuki Nakano
Toshiki Sotoyama
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.