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US3540912A
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US
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Pressure sensitive record sheets employing 3 - (phenyl) - 3 - (heterocyclic-substituted)-phthalides
Assignee: Appvion LLC
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Filing: 1969-01-24
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Granted: 1970-11-17
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Expires: 1989-01-24
Abstract
No abstract record available.
Inventors
- 👤 Chao-Han Lin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:25
CPC Classifications
C; C09; C09B; C09B11/00; C09B11/04; C09B11/26; B; B41; B41M; B41M5/00; B41M5/124; B41M5/132; B41M5/136; B41M5/145; C09B11/06; C09B11/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2505486A
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US3244549A
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US3268537A
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US3336337A
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US3455721A
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US3491112A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-16 | 1974-05-18 | 1974-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-16 | 1978-05-18 | 1978-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-16 | 1982-05-18 | 1982-11-17 | $7700.00 | Window Closed / Lapsed |