Granted Patent
Utility
US 5,202,104 · App. 07/481,235
Process for preparing silica having a low silanol content
Inventors:
Naotake Watanabe, Koichi Orii, Junsuke Yagi, Iwao Ohshima
Patented Case
View Patent ↗
Granted: Apr 13, 1993
Filed: Feb 20, 1990
Inventors
Naotake Watanabe
Koichi Orii
Junsuke Yagi
Iwao Ohshima
Assignee (at issue)
Nitto Chemical Industry Co., 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.