Granted Patent
Utility
US 6,031,136 · App. 08/094,933
Process for preparing methylene diphenylamines by partial neutralization of acidic methylene diphenylamines
Inventors:
Louis Renbaum, Mark S. Solomon, William D. Tippins
Patented Case
View Patent ↗
Granted: Feb 29, 2000
Filed: Jul 21, 1993
Inventors
Louis Renbaum
Mark S. Solomon
William D. Tippins
Assignee (at issue)
Bayer Aktiengesellschaft
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.