Granted Patent
Utility
US 4,511,640 · App. 06/525,927
Aqueous developable diazo lithographic printing plates with admixture of polyvinyl acetate and styrene maleic acid ester copolymer
Inventor:
Shuchen Liu
Patented Case
View Patent ↗
Granted: Apr 16, 1985
Filed: Aug 25, 1983
Inventor
Shuchen Liu
Assignee (at issue)
American Hoechst 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.