Granted Patent
Utility
US 5,645,859 · App. 08/537,566
Process for producing an alpha or beta-hydroxy acid-vinylpyrrolidone polymer, copolymer or graft polymer complex in the form of free-flowing powders having a high acid loading
Inventors:
Ratan K. Chaudhuri, Russell B. Biss, John J. Merianos
Patented Case
View Patent ↗
Granted: Jul 8, 1997
Filed: Oct 2, 1995
Inventors
Ratan K. Chaudhuri
Russell B. Biss
John J. Merianos
Assignee (at issue)
ISP INVESTMENTS LLC
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.