Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4954631 | Fluoran compounds and color forming recording materials using same | Yutaka Ohnishi, Shinji Yoshinaka, Minoru Koguchi, Mitsuhiro Yanagita, Nobuyuki Hirai | 1990-09-04 |
| 4826806 | Fluoran compounds and color forming recording materials using same | Yutaka Ohnishi, Shinji Yoshinaka, Minoru Koguchi, Mitsuhiro Yanagita, Nobuyuki Hirai | 1989-05-02 |
| 4794069 | Spirobenzanthracene phthalide compounds, processes for preparing same and color forming recording materials containing said compounds | Yutaka Ohnishi, Shinji Yoshinaka, Toshiyuki Tanaka, Minoru Koguchi | 1988-12-27 |
| 4687862 | Fluoran compounds | Tetsuo Igaki, Kimiaki Kinoshita, Morio Nanbu, Shinichi Satoh | 1987-08-18 |
| 4680598 | Chromogenic materials employing fluoran compounds | Tetsuo Igaki, Kimiaki Kinoshita, Morio Nanbu, Shinichi Satoh | 1987-07-14 |
| 4668967 | Fluoran compound and color forming record materials using the same | Masakichi Yahagi, Tetsuo Igaki, Kazuyuki Horisawa, Morio Nanbu, Kimiaki Kinoshita +1 more | 1987-05-26 |