US3669711A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure-sensitive copying paper
Assignee: Fujifilm Holdings Corp
•
Filing: 1970-05-22
•
Granted: 1972-06-13
•
Expires: 1990-05-22
Abstract
Abstract PRESSURE-SENSITVE COPYING PAPERS CONTAINING A FLUORAN DERIVATIVE HAVING THE FOLLOWING GENERAL FORMULA 3-(R1-N(-R2-),7-(R4-N(-R3-)SPIRO(PHTHALAN-1,9''-XANTHENE) WHEREIN R1 AND R2 EACH REPRESENTS AN ALKYL GROUP HAVING FROM 1 TO 5 CARBON ATOMS; WHEREIN R3 REPRESENTS A HYDROGEN ATOM, AN ALKYL GROUP HAVING FROM 1 TO 5 CARBON ATOMS, OR A BENZYL GROUP; AND WHEREIN R4 REPRESENTS AN ARYL GROUP ARE DISCLOSED.
Inventors
- 👤 Shiro Kimura
- 👤 Sadao Ishige
- 👤 Masataka Kiritani
- 👤 Teruo Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:20
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/124; B41M5/132; B41M5/136; B41M5/145; B41M5/1455; C; C09; C09B; C09B11/00; C09B11/04; C09B11/10; C09B11/24; Y; Y10; Y10S; Y10S428/00; Y10S428/914; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31844; Y10T428/31848
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |