Granted Patent
Utility
US 4,729,984 · App. 06/894,498
Heat sensitive recording sheets containing sulfone derivatives
Inventors:
Fumio Hama, Masayuki Omatsu, Mitsuru Kondo
Patented Case
View Patent ↗
Granted: Mar 8, 1988
Filed: Aug 4, 1986
Inventors
Fumio Hama
Masayuki Omatsu
Mitsuru Kondo
Assignee (at issue)
Kanzaki Paper Manufacturing Co., 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.