Patent US3454874A successfully refreshed from Google Patents.
US3454874A
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Instrument for measuring the thickness of a non-conducting film on a metal base and for measuring the resistivity of a metal sample
Assignee: British Aluminum Co Ltd
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Filing: 1965-03-08
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Granted: 1969-07-08
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Expires: 1985-03-08
Abstract
No abstract record available.
Inventors
- 👤 Reginald Searles Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:43
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/08; H03B5/10; G; G01; G01B; G01B7/00; G01B7/02; G01B7/06; G01B7/10; G01B7/105
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2919413A
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US2920268A
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US2933677A
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US2920269A
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US2939073A
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US3135914A
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US3260927A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-07-07 | 1973-01-06 | 1973-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-07-07 | 1977-01-06 | 1977-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-07-07 | 1981-01-06 | 1981-07-08 | $7700.00 | Window Closed / Lapsed |