IP Library › Granted Patent US 5,294,521
Granted Patent Utility
US 5,294,521 · App. 08/003,206

Positive photoresists employing an isomeric mixture of two hexahydroxybenzophenone esters of diazonaphthoquinone sensitizers

Inventors: Elaine C. Jacovich, Wells Cunningham
Patented Case View Patent ↗
Granted: Mar 15, 1994 Filed: Jan 12, 1993
Inventors
Elaine C. Jacovich
Wells Cunningham
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 5,294,521
App. No.
08/003,206
Filed
1993-01-12
Granted
1994-03-15
Kind
A