US3620680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for continuously making thermoplastic polyurethanes
Assignee: Kunststoffbuero Osnabrueck Dr Reuter GmbH and Co KG
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Filing: 1969-07-24
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Granted: 1971-11-16
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Expires: 1989-07-24
Abstract
Abstract A process and an apparatus for making thermoplastic polyurethanes continuously, the apparatus combining a storage tank and dehydrating equipment for a polyol and storage tanks for other components of a polyurethane reaction mixture all connected through conduits to a mixing device which discharges the reaction mixture continuously over the surface of a conveyor belt. The conveyor belt is provided with means for controlling the temperature thereof. The solidified thermoplastic product discharged from the belt is continuously granulated and conveyed to containers.
Inventors
- 👤 Gunter Friedrich Bartel
- 👤 Martin Klawitter
- 👤 Ernst Denker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 03:01
CPC Classifications
B; B29; B29B; B29B7/00; B29B7/74; B29B7/7476; B29B7/7485; B01; B01J; B01J2/00; B01J2/26; C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/0895; C08G18/28; C08G18/65; C08G18/66; C08G18/6603; C08G18/6607
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
21 words
The apparatus of claim 1 wherein said conveyor is provided with means for blowing air over a layer of polyurethane thereon.
Claim 2
Dependent Claim
45 words
The apparatus of claim 1 wherein said means for charging an additional component to the second mixer comprises a bin adapted for storage of solid diisocyanate and means comprising a conveyor for transferring measured quantities of the diisocyanate as a solid to the second mixer.
Claim 3
Independent Claim
243 words
An apparatus for making thermoplastic polyurethanes which comprises a bin for storing a polyol and having a discharge opening, a trough sloping downwardly from said discharge opening and adapted to receive polyol discharged through said opening, means for heating the trough and for discharging polyol therefrom, a first tank situated to receive polyol discharged from the trough, means for heating the first tank, a dehydrator, means for transferring the polyol from the first tank to the dehydrator, a second tank, means for transferring polyol from the dehydrator to the second tank, means for transferring measured amounts of polyol from the second tank to a first mixer, means for charging measured amounts of another component of polyurethane reaction mixture to the first mixer, means for transferring the resulting mixture to a second mixer, means for charging at least one other component of a polyurethane reaction mixture to the second mixer, means for mixing the contents of the second mixer substantially uniformly, means for discharging the resulting mixture from the second mixer, means comprising a conveyor belt running at a substantially constant speed adjacent a discharge opening of said second mixer and adapted to receive liquid discharged from the mixer as a layer spread over its surface, means for heating the said layer near the said second mixer, means spaced from said second mixer for cooling the layer, and means for collecting the product from the end of the conveyor spaced from said second mixer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |