Granted Patent
Utility
US 4,335,089 · App. 06/182,611
Process for producing carbon fibers
Inventors:
Kunio Maruyama, Akira Okazaki
Patented Case
View Patent ↗
Granted: Jun 15, 1982
Filed: Aug 29, 1980
Inventors
Kunio Maruyama
Akira Okazaki
Assignee (at issue)
SUMITOMO CHEMICAL COMPANY, LIMITED
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.