Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4874633 | Method of producing magnetic recording medium | Hiroshi Chikamasa, Tsunehiko Sato | 1989-10-17 |
| 4844946 | Method for preparing a magnetic recording medium | Hiroshi Chikamasa, Tsunehiko Sato | 1989-07-04 |