IP Library Granted Patent US 4,857,293
Granted Patent Utility
US 4,857,293 · App. 07/109,360

Process for the preparation of ultrapure heavy metal fluorides

Inventors: Ricardo C. Pastor, Luisa E. Gorre
Patented Case View Patent ↗
Granted: Aug 15, 1989 Filed: Oct 15, 1987
Inventors
Ricardo C. Pastor
Luisa E. Gorre
Assignee (at issue)
Hughes Aircraft Company

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 4,857,293
App. No.
07/109,360
Filed
1987-10-15
Granted
1989-08-15
Kind
A