Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4848960 | Finishing machine for a concrete surface | Yasuo Kajioka, Tomio Komine, Satoru Shimizu | 1989-07-18 |
| 4810678 | Gas pressure sintering of silicon nitride with addition of rare earth oxides | Naoto Hirosaki | 1989-03-07 |