US3428424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of nitric acid
Assignee: Engelhard Industries Inc
•
Filing: 1965-02-24
•
Granted: 1969-02-18
•
Expires: 1985-02-24
Abstract
No abstract record available.
Inventors
- 👤 Carl D Keith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:12
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/20; C01B21/24; C01B21/26; C01B21/265; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB464706A
Cited
US2970034A
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US2975025A
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US2955917A
Cited
GB882484A
Cited
US3079232A
Cited
US3003851A
Cited
US3208131A
Cited
US3136602A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-02-18 | 1972-08-19 | 1973-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-18 | 1976-08-19 | 1977-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-18 | 1980-08-19 | 1981-02-18 | $7700.00 | Window Closed / Lapsed |