Issued Patents All Time
Showing 1–10 of 10 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 12054622 | Oil-based ink composition for writing utensils, writing utensil using same, and airbrush unit using same | Yumiko Haruhara | 2024-08-06 |
| 11654711 | Writing tool provided with refill | Seiichi Maruyama, Kiyoshi Iwamoto | 2023-05-23 |
| 11135868 | Refill for writing implements and writing implements using the same | — | 2021-10-05 |
| 10569596 | Writing tool refill and writing tool using same | Seiichi Takigawa, Naohiro Katou, Takanori Shindou | 2020-02-25 |
| 7381754 | Oil-based ink composition and uses thereof | Shuuji Ichikawa | 2008-06-03 |
| 7311459 | Follower for non-aqueous ball point pen and non-aqueous ball point pen | Shuji Ichikawa | 2007-12-25 |
| 6945726 | Refill for oil-based ink ballpoint pen and oil-based ink ballpoint pen | Syuji Ichikawa, Miyuki Shouji, Daisen Katou, Takeshi Kobayashi | 2005-09-20 |
| 6830611 | Oil-base ink composition, writing utensils and dyes to be used therein | Shuuji Ichikawa | 2004-12-14 |
| 6441061 | Additive for oil-based ink for a ball point pen and oil based ink for a ball point pen containing the same | — | 2002-08-27 |
| 5942027 | Ink for ball point pen | Misao Oyama | 1999-08-24 |