Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4808192 | Process for preparation of water soluble dyes containing lithium sulfonate group or ammonium sulfonate group by cation exchange, neutralization and reverse osmosis | Hiroshi Takimoto, Hideo Sano | 1989-02-28 |