Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4880762 | Coloring phthalide compounds, method of producing the compounds and recording materials using any of the compounds as coloring component | Kunio Hayakawa | 1989-11-14 |
| 4845072 | Thermosensitive recording material | Hiromi Furuya | 1989-07-04 |