Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886767 | Silicon nitride-ceramic and a manufacturing method therof | Yasuhiro Goto, Yoshiyuki Ohnuma | 1989-12-12 |
| 4853299 | Silicon carbide sintered body and method of manufacturing the same | Toshiaki Mizutani, Hiroshi Inoue, Akihiko Tsuge, Yoshiyuki Ohnuma | 1989-08-01 |