Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4897752 | Disk cartridge | Hajime Doi, Toru Yamakawa, Kunio Mizushima | 1990-01-30 |
| 4803584 | Disk cartridge with cleaning sheet of non-woven fabric | Hajime Doi, Norio Akai | 1989-02-07 |
| 4709816 | Recording disc cartridge | Hajime Doi, Kunio Mizushima, Masaya Funahashi, Tomizo Taniguchi, Shoichi Sakamoto | 1987-12-01 |
| 4630728 | Disc cartridge | Yoshitake Kato | 1986-12-23 |