Granted Patent
Utility
US 5,166,271 · App. 07/401,833
Heat resistant polyvinyl chloride copolymer and preparation process of the copolymer
Inventors:
Seiichi Masuko, Hideaki Takahara, Akira Yamamoto
Patented Case
View Patent ↗
Granted: Nov 24, 1992
Filed: Sep 1, 1989
Inventors
Seiichi Masuko
Hideaki Takahara
Akira Yamamoto
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.