Granted Patent
Utility
US 4,791,185 · App. 07/116,959
High-refractivity plastic lens resin formed from a polyisocyanate and a polythiol
Inventors:
Yoshinobu Kanemura, Katsuyoshi Sasagawa, Masao Imai, Teruyuki Nagata, Nobuyuki Kajimoto
Patented Case
View Patent ↗
Granted: Dec 13, 1988
Filed: Nov 5, 1987
Inventors
Yoshinobu Kanemura
Katsuyoshi Sasagawa
Masao Imai
Teruyuki Nagata
Nobuyuki Kajimoto
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.