Patent US3418204A successfully refreshed from Google Patents.
US3418204A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyalkylene imine partially cross-linked with formaldehyde and pigment retention in paper-making therewith
Assignee: Chemirad Corp
•
Filing: 1965-08-04
•
Granted: 1968-12-24
•
Expires: 1985-08-04
Abstract
No abstract record available.
Inventors
- 👤 Goldstein Albert
- 👤 Donald R Hobbs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:42
CPC Classifications
D; D06; D06P; D06P1/00; D06P1/44; C; C08; C08G; C08G73/00; C08G73/02; C08G73/0206; C08G73/0213
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2272489A
Cited
US2296225A
Cited
US2849411A
Cited
US2999782A
Cited
GB996388A
Cited
US3267054A
Cited
US3325346A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-12-24 | 1972-06-24 | 1972-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-12-24 | 1976-06-24 | 1976-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-12-24 | 1980-06-24 | 1980-12-24 | $7700.00 | Window Closed / Lapsed |