Patent US3834441A successfully refreshed from Google Patents.
US3834441A
Expired / Lapsed
US
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Process for concentrating polymer solutions by evaporation
Assignee: Bayer AG
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Filing: 1972-08-07
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Granted: 1974-09-10
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Expires: 1992-08-07
Abstract
Abstract Polymer solutions are concentrated by evaporation, whereby the solution is heated under pressure and expanded through a nozzle into a coiled tube in which a decreasing pressure gradient is maintained in direction of flow and the gas velocity is increased and the temperature is raised above the melting temperature of the polymer.
Inventors
- 👤 H Vernaleken
- 👤 O Court
- 👤 L Bottenbruch
- 👤 A Lippert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:31
CPC Classifications
C; C08; C08J; C08J3/00; B; B01; B01D; B01D3/00; B01D3/06; C08G; C08G64/00; C08G64/20; C08G64/205; C08J2369/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
27 words
A process according to claim 1 wherein the decreasing pressure gradient is maintained by an increasing cross section of the polymer solution in the direction of flow.
References Cited (Backward Citations)
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US2689839A
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US2853127A
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US3453184A
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US3357955A
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US3386488A
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US3469617A
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US3550669A
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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) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |