Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5609789 | Cobalt-containing magnetic iron oxide and process for producing the same | Kiyoshi Asano, Arata Koyama, Nobusuke Takumi, Kouichi Tamura, Tokuo Suita | 1997-03-11 |
| 5041307 | Process for producing magnetic iron oxide particles for magnetic recording | Arata Koyama, Makoto Ogasawara | 1991-08-20 |