Granted Patent
Utility
US 4,433,133 · App. 06/479,811
Process for producing crosslinked urea-formaldehyde polymer particles
Inventors:
Naoyuki Ifuku, Akio Kurokawa, Kenzo Seita, Kaoru Usami, Naoyuki Aikawa
Patented Case
View Patent ↗
Granted: Feb 21, 1984
Filed: Mar 28, 1983
Inventors
Naoyuki Ifuku
Akio Kurokawa
Kenzo Seita
Kaoru Usami
Naoyuki Aikawa
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated
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.