Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4861378 | Cement additive containing superplasticizer and bentonite | Yoshiharu Watanabe, Mineo Ito, Hitoshi Moriyama | 1989-08-29 |
| 4849901 | Substrate exposure apparatus with flatness detection and alarm | — | 1989-07-18 |