Patent US3337508A successfully refreshed from Google Patents.
US3337508A
Expired / Lapsed
US
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Process for continuous preparation of condensation polymers
Assignee: Hoechst AG
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Filing: 1963-01-29
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Granted: 1967-08-22
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Expires: 1983-01-29
Abstract
No abstract record available.
Inventors
- 👤 Bachmann Ditmar
- 👤 Gerstenberg Helmut
- 👤 Paszthory Emmerich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:32
CPC Classifications
B; B01; B01D; B01D1/00; B01D1/22; B01D1/222; B01D1/228; B01F; B01F27/00; B01F27/05; B01F27/09; B01F27/092; B01F27/11; B01F27/19; B01F27/192; B01F27/60; B01J; B01J19/00; B01J19/18; B01J19/20; C; C08; C08G; C08G63/00; C08G63/78; C08G63/785; C08G69/00; C08G69/02; C08G69/04; C08G85/00; B01J2219/00; B01J2219/00049; B01J2219/00051; B01J2219/00132; B01J2219/00162; B01J2219/18; B01J2219/182
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
118 words
IN A PROCESS FOR CONTINUOUS POLYCONDENSATION OF A MELT OF A LINEAR SATURATED OR UNSATURETED POLYESTER, POLYETHER OR POLYAMIDE BY HEATING THE MELT UNDER REDUCED PRESSURE, THE IMPROVEMENT WHICH COMPRISES CONTINUOUSLY FEEDING THE MELT INTO AND THROUGH A PLURALITY OF SUCCESSIVE HEATING STAGES PROVIDED WITH INTERMEDIATE DAMMING MEANS, SPREADING A PORTION OF THE MELT IN EACH HEATING STAGE IN THE FORM OF A LAYER ON A HEATED SURFACE FOR HEATING SAID PORTION UNDER REDUCED PRESSURE, CONTINUOUSLY RETURNING SAID HEATED PORTION OF THE MELT IN EACH STAGE FROM SAID HEATED SURFACE TO THE MELT IN SAID STAGE FOR ADMIXTURE THEREWITH, AND FEEDING SAID MIXTURE OVER SAID INTERMEDIATE DAMMING MEANS UNTIL IT IS CONTINUOUSLY WITHDRAWN FROM THE LAST HEATING STAGE.
Claim 2
Dependent Claim
118 words
IN A PROCESS FOR CONTINUOUS POLYCONDENSATION OF A MELT OF A LINEAR SATURATED OR UNSATURETED POLYESTER, POLYETHER OR POLYAMIDE BY HEATING THE MELT UNDER REDUCED PRESSURE, THE IMPROVEMENT WHICH COMPRISES CONTINUOUSLY FEEDING THE MELT INTO AND THROUGH A PLURALITY OF SUCCESSIVE HEATING STAGES PROVIDED WITH INTERMEDIATE DAMMING MEANS, SPREADING A PORTION OF THE MELT IN EACH HEATING STAGE IN THE FORM OF A LAYER ON A HEATED SURFACE FOR HEATING SAID PORTION UNDER REDUCED PRESSURE, CONTINUOUSLY RETURNING SAID HEATED PORTION OF THE MELT IN EACH STAGE FROM SAID HEATED SURFACE TO THE MELT IN SAID STAGE FOR ADMIXTURE THEREWITH, AND FEEDING SAID MIXTURE OVER SAID INTERMEDIATE DAMMING MEANS UNTIL IT IS CONTINUOUSLY WITHDRAWN FROM THE LAST HEATING STAGE.
References Cited (Backward Citations)
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US3082816A
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US2964391A
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US2992679A
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US3118739A
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US3167531A
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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) | 1970-08-21 | 1971-02-20 | 1971-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-08-21 | 1975-02-20 | 1975-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-08-21 | 1979-02-20 | 1979-08-22 | $7700.00 | Window Closed / Lapsed |