IP Library › Granted Patent US 4,863,621
Granted Patent Utility
US 4,863,621 · App. 07/001,783

Sulfur-and nitrogen-containing lubricant additives

Inventors: Hermann O. Wirth, Hans-Helmut Friedrich
Patented Case View Patent ↗
Granted: Sep 5, 1989 Filed: Jan 9, 1987
Inventors
Hermann O. Wirth
Hans-Helmut Friedrich
Assignee (at issue)
Ciba-Geigy

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 4,863,621
App. No.
07/001,783
Filed
1987-01-09
Granted
1989-09-05
Kind
A