Granted Patent
Utility
US 5,604,994 · App. 08/392,200
Drying hopper and powder drying method using the same
Inventors:
Yoshiaki Annen, Akira Tsuzaki, Isao Shizuma, Takao Uetake, Mitsunori Ichimura
Patented Case
View Patent ↗
Granted: Feb 25, 1997
Filed: Feb 22, 1995
Inventors
Yoshiaki Annen
Akira Tsuzaki
Isao Shizuma
Takao Uetake
Mitsunori Ichimura
Assignee (at issue)
Mitsui Petrochemical 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.