Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4674592 | Diaphragm for use in electro-acoustic transducer | Shuichi Aoki, Akihiko Haga, Minoru Ito | 1987-06-23 |
| 4451609 | Flame-retarded acoustic diaphragm | Fumio Kawahara, Masanori Takahashi | 1984-05-29 |