US3516910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removing and inhibiting scale in black liquor evaporators
Assignee: WR Grace and Co
•
Filing: 1967-05-12
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Granted: 1970-06-23
•
Expires: 1987-05-12
Abstract
No abstract record available.
Inventors
- 👤 William C Engman
- 👤 Walter W Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:59
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; Y; Y10; Y10S; Y10S159/00; Y10S159/13; Y10S210/00; Y10S210/928
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |