Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7456321 | Process for producing high-purity 4,4′-dihydroxydiphenyl sulfone | Eiji Ogata, Fumio Oi, Nobuyuki Nate | 2008-11-25 |
| 6974886 | Process for producing dihydroxydiphenylsulfone | Fumio Oi, Takayuki Kitahara, Nobuyuki Nate | 2005-12-13 |
| 6965054 | Process for producing mixture of dihydroxydiphenylsulfone isomers | Fumio Oi, Masamichi Yamamoto | 2005-11-15 |
| 6861562 | Process for producing mixture of dihydroxydiphenylsulfone isomers | Fumio Oi, Hiroyuki Yamamoto | 2005-03-01 |
| 5596128 | Sulfonating agent and sulfonation process | Eiji Ogata, Takayuki Kitahara | 1997-01-21 |