Granted Patent
Utility
US 4,609,681 · App. 06/818,312
Anti-lumping styrene polymer particles for molding foams
Inventor:
Alvin R. Ingram
Patented Case
View Patent ↗
Granted: Sep 2, 1986
Filed: Jan 13, 1986
Inventor
Alvin R. Ingram
Assignee (at issue)
Atlantic Richfield 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.