Granted Patent
Utility
US 4,414,378 · App. 06/368,729
Granular or powdery phenol-formaldehyde resin and process for production thereof
Inventors:
Hiroaki Koyama, Shigeo Shimizu
Patented Case
View Patent ↗
Granted: Nov 8, 1983
Filed: Apr 15, 1982
Inventors
Hiroaki Koyama
Shigeo Shimizu
Assignee (at issue)
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.