Patent US3951748A successfully refreshed from Google Patents.
US2420172A
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Electrical insulating material containing mica
Assignee: Mica Insulator Co
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Filing: 1940-12-06
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Granted: 1947-05-06
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Expires: 1960-12-06
Abstract
No abstract record available.
Inventors
- 👤 Robert L Griffeth
- 👤 Joseph J Pickney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:07
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/02; H01B3/04; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/251; Y10T428/31504; Y10T428/31551; Y10T428/31645; Y10T428/31652; Y10T428/31667; Y10T442/00; Y10T442/30; Y10T442/3472; Y10T442/3602; Y10T442/3699
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2054356A
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US2138895A
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GB508035A
Cited
GB508057A
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US2183811A
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US2278207A
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US2194958A
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US2320866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-05 | 1950-11-04 | 1951-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-05 | 1954-11-04 | 1955-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-05 | 1958-11-04 | 1959-05-06 | $7700.00 | Window Closed / Lapsed |