Issued Patents 1997
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5693830 | Process for preparing the spiropyrone compounds | Satoshi Imura, Takashi Kobayakawa | 1997-12-02 |
| 5621017 | Photochromic composition and method producing photochromic cured product | Takashi Kobayakawa | 1997-04-15 |