IP Library Granted Patent US 4,997,952
Granted Patent Utility
US 4,997,952 · App. 07/420,767

N-pyrrolidonyl methyltriphenyl phosphonium salts and method for their preparation and use

Inventors: Kolazi S. Narayanan, Paul D. Taylor
Patented Case View Patent ↗
Granted: Mar 5, 1991 Filed: Oct 12, 1989
Inventors
Kolazi S. Narayanan
Paul D. Taylor
Assignee (at issue)
GAF 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.

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 4,997,952
App. No.
07/420,767
Filed
1989-10-12
Granted
1991-03-05
Kind
A