Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4844963 | Magnetic disk and method of manufacturing same | Eiichi Takasuna | 1989-07-04 |
| 4842618 | Method of producing magnetic disk | Yasushi Ito, Yoshiki Kato, Jun Fumioka | 1989-06-27 |