Granted Patent
Utility
US 5,196,578 · App. 07/758,362
Purification process of methacrylic acid
Inventors:
Morimasa Kuragano, Takeshi Isobe, Nobutaka Ueda, Minoru Koshibe, Yoshihiro Sezaki, Hirozo Segawa, Katsuji Yoguchi, Rensuke Ikarashi
Patented Case
View Patent ↗
Granted: Mar 23, 1993
Filed: Sep 10, 1991
Inventors
Morimasa Kuragano
Takeshi Isobe
Nobutaka Ueda
Minoru Koshibe
Yoshihiro Sezaki
Hirozo Segawa
Katsuji Yoguchi
Rensuke Ikarashi
Assignees (at issue)
Mitsui Toatsu Chemicals, Incorporated
KURARAY 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.