IP Library Granted Patent US 4,699,681
Granted Patent Utility
US 4,699,681 · App. 06/308,827

Method of making a gas phase permeable filter

Inventors: James W. Kasmark, Jr., Myron L. Dooley, Arthur H. Jones
Patented Case View Patent ↗
Granted: Oct 13, 1987 Filed: Oct 5, 1981
Inventors
James W. Kasmark, Jr.
Myron L. Dooley
Arthur H. Jones
Assignee (at issue)
D-Mark, Inc.

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 4,699,681
App. No.
06/308,827
Filed
1981-10-05
Granted
1987-10-13
Kind
A