Granted Patent
Utility
US 5,681,790 · App. 08/565,712
Catalyst for preparing methacrylic acid
Inventors:
Young Chul Kim, Ki-Hwa Lee, Eun Hee Jin
Patented Case
View Patent ↗
Granted: Oct 28, 1997
Filed: Nov 30, 1995
Inventors
Young Chul Kim
Ki-Hwa Lee
Eun Hee Jin
Assignee (at issue)
Samsung General Chemicals, 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.