Patent US1457436A successfully refreshed from Google Patents.
US1457436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of making metal sulphides
Assignee: Grasselli Chemical Co
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Filing: 1921-12-29
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Granted: 1923-06-05
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Expires: 1941-12-29
Abstract
No abstract record available.
Inventors
- 👤 Howard Henry
- 👤 Alvord Earl Burnard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:48
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/42; C01B17/44; C01B17/22; C01B17/24; C01B17/28; C01G; C01G1/00; C01G1/12
Claims Analysis
Total Claims: 0
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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) | 1926-06-04 | 1926-12-04 | 1927-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1930-06-04 | 1930-12-04 | 1931-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1934-06-04 | 1934-12-04 | 1935-06-05 | $7700.00 | Window Closed / Lapsed |