Granted Patent
Utility
US 4,929,706 · App. 07/319,458
Cell growth enhancers and/or antibody production stimulators comprising chemically modified hydrophilic polyurea-urethane prepolymers and polymers
Inventors:
Aaron H. Heifetz, Richard A. Wolfe, James A. Braatz, Narender P. Luthra
Patented Case
View Patent ↗
Granted: May 29, 1990
Filed: Mar 3, 1989
Inventors
Aaron H. Heifetz
Richard A. Wolfe
James A. Braatz
Narender P. Luthra
Assignee (at issue)
W.R. Grace & Co. Conn.
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.