Patent US2183790A successfully refreshed from Google Patents.
US2183790A
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US
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Opaque materials for x-ray and radium work or the like
Assignee: Richardson Co
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Filing: 1935-03-21
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Granted: 1939-12-19
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Expires: 1955-03-21
Abstract
No abstract record available.
Inventors
- 👤 Edward R Dillehay
- 👤 Ellyn Glen
- 👤 George M Mcfedries
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:24
CPC Classifications
G; G21; G21F; G21F1/00; G21F1/12; G21F1/125; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/927; Y10S428/9335; Y10S428/934; Y10S428/935; Y10T; Y10T156/00; Y10T156/10; Y10T428/00; Y10T428/12; Y10T428/12229; Y10T428/12236; Y10T428/12493; Y10T428/12535; Y10T428/12542; Y10T428/12549; Y10T428/12556; Y10T428/12569; Y10T428/12701; Y10T428/12986; Y10T428/18; Y10T428/31504; Y10T428/31678; Y10T428/31688
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) | 1942-12-18 | 1943-06-19 | 1943-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-12-18 | 1947-06-19 | 1947-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-12-18 | 1951-06-19 | 1951-12-19 | $7700.00 | Window Closed / Lapsed |