Granted Patent
Utility
US 4,243,728 · App. 05/964,231
Double-metal-coated metal sulfide powder and process of producing the same
Inventors:
Haruki Sato, Yoshio Kawasumi
Patented Case
View Patent ↗
Granted: Jan 6, 1981
Filed: Nov 28, 1978
Inventors
Haruki Sato
Yoshio Kawasumi
Assignee (at issue)
Nihon Kogyo 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.