Patent US2444712A successfully refreshed from Google Patents.
US2444712A
Expired / Lapsed
US
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Light polarizing polyvinyl orthoborate films
Assignee: EIDP Inc
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Filing: 1945-07-06
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Granted: 1948-07-06
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Expires: 1965-07-06
Abstract
No abstract record available.
Inventors
- 👤 Signaigo Frank Kerr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:17
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; G02B5/3025; G02B5/3033; G02B27/00; G02B27/28; G02B27/288
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2328219A
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US2237567A
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US2270323A
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US2255940A
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US2327872A
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US2300074A
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US2310223A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-07-06 | 1952-01-05 | 1952-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-07-06 | 1956-01-05 | 1956-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-07-06 | 1960-01-05 | 1960-07-06 | $7700.00 | Window Closed / Lapsed |