Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4840843 | Magnetic recording medium | Kunihiko Sano, Makoto Nagao, Akira Nahara, Yasuo Nishikawa | 1989-06-20 |
| 4834926 | Process for producing silicon nitride ceramic articles | Masaaki Masuda | 1989-05-30 |