Patent US1666423A successfully refreshed from Google Patents.
US1666423A
Expired / Lapsed
US
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Process of staining and hardening concrete and the like
Assignee: Individual
•
Filing: 1923-04-02
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Granted: 1928-04-17
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Expires: 1943-04-02
Abstract
No abstract record available.
Inventors
- 👤 Robert B Lammens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:17
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B24/00; C04B24/10; C04B41/45; C04B41/52; C04B41/60; C04B41/61; C04B41/70
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) | 1931-04-17 | 1931-10-17 | 1932-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-04-17 | 1935-10-17 | 1936-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-04-17 | 1939-10-17 | 1940-04-17 | $7700.00 | Window Closed / Lapsed |