Granted Patent
Utility
US 5,883,769 · App. 08/885,584
Aluminum head drum with a protective layer which smoothly and continuously varies in hardness for use in a videocassette recorder
Inventors:
Kye-Chul Choi, Keum-Mo Kim, Kwang Yong Eun, Kwang Ryeol Lee
Patented Case
View Patent ↗
Granted: Mar 16, 1999
Filed: Jun 30, 1997
Inventors
Kye-Chul Choi
Keum-Mo Kim
Kwang Yong Eun
Kwang Ryeol Lee
Assignee (at issue)
Daewoo Electronics Corporation
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.