Granted Patent
Utility
US 4,414,379 · App. 06/388,974
Granular or powdery nitrogen-containing phenol-aldehyde copolymer resin and process for production thereof
Inventors:
Hiroaki Koyama, Shigeo Shimizu
Patented Case
View Patent ↗
Granted: Nov 8, 1983
Filed: Jun 16, 1982
Inventors
Hiroaki Koyama
Shigeo Shimizu
Assignees (at issue)
KANEBO, LIMITED
Mitsubishi Chemical Industries, Ltd.
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.