Granted Patent
Utility
US 5,708,152 · App. 08/451,324
N-substituted chitosan derivatives in a process for their preparation
Inventors:
Dieter Lohmann, Donald Richard Randell
Patented Case
View Patent ↗
Granted: Jan 13, 1998
Filed: May 26, 1995
Inventors
Dieter Lohmann
Donald Richard Randell
Assignee (at issue)
Ciba Specialty Chemicals 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.