IP Library Granted Patent US 4,894,119
Granted Patent Utility
US 4,894,119 · App. 06/721,876

Retention and/or drainage and/or dewatering aid

Inventors: Joseph J. Baron, Jr., Tamara Nowakowski, Thomas Farrington, Frederick R. Mahn
Patented Case View Patent ↗
Granted: Jan 16, 1990 Filed: Apr 10, 1985
Inventors
Joseph J. Baron, Jr.
Tamara Nowakowski
Thomas Farrington
Frederick R. Mahn
Assignee (at issue)
Drew Chemical 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.

Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 4,894,119
App. No.
06/721,876
Filed
1985-04-10
Granted
1990-01-16
Kind
A