IP Library Granted Patent US 5,449,457
Granted Patent Utility
US 5,449,457 · App. 07/688,178

Liquid membrane modules with minimal effective membrane thickness and methods of making the same

Inventor: Ravi Prasad
Patented Case View Patent ↗
Granted: Sep 12, 1995 Filed: Apr 22, 1991
Inventor
Ravi Prasad
Assignee (at issue)
Hoechst Celanese 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 5,449,457
App. No.
07/688,178
Filed
1991-04-22
Granted
1995-09-12
Kind
A