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Patent US3501275A successfully refreshed from Google Patents.
US3501275A
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Apparatus for continuously separating mixtures of substances by multistage rectifying column crystallization
Assignee: Inventa AG fuer Forschung und Patentverwertung
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Filing: 1968-05-27
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Granted: 1970-03-17
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Expires: 1988-05-27
Abstract
No abstract record available.
Inventors
- 👤 Richard Sailer
- 👤 Hanswerner Philipp
- 👤 Clau Berther
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:27
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/16; B; B01; B01D; B01D9/00; B01D9/0004; B01D9/0013; B01D9/004; B01D9/005; C07C; C07C37/00; C07C37/68; C07C37/70; C07C37/74; C07C37/84
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2919991A
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US3255598A
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US3261170A
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US3392539A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |