Patent US3996321A successfully refreshed from Google Patents.
US3996321A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Level control of dry-jet wet spinning process
Assignee: EIDP Inc
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Filing: 1974-11-26
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Granted: 1976-12-07
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Expires: 1994-11-26
Abstract
Abstract In a process for forming fibers by extruding a spinning dope successively through a layer of inert gas and a tube immersed in a coagulating bath, the tension profile of the yarn passing through the tube is regulated by regulating the pressure of the layer inert gas. In this pressurized quench system, the coagulating liquid is maintained at a predetermined level, despite transient changes in liquid input, by passing both pressurized gas and coagulating liquid through a pipe having an opening at the level to be maintained.
Inventors
- 👤 Charles Brian Weinberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:38
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/12; D01D5/14; D01D5/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
119 words
In a wet spinning process for forming fibers that includes the steps of extruding a spinning dope from an orifice through a layer of inert gas and through a liquid quench coagulating bath by passing the fiber through a tube in said bath co-currently with a portion of said bath and adding quench liquid to said bath in an amount at least as great as said portion, the improvement comprising: applying a gas pressure to said layer of inert gas; self-regulating the inert gas pressure in said layer; and self-regulating the liquid in said bath at a predetermined level by continuously passing the pressurized inert gas and quench liquid through a restricted pipe having an opening at said level.
Claim 2
Dependent Claim
119 words
In a wet spinning process for forming fibers that includes the steps of extruding a spinning dope from an orifice through a layer of inert gas and through a liquid quench coagulating bath by passing the fiber through a tube in said bath co-currently with a portion of said bath and adding quench liquid to said bath in an amount at least as great as said portion, the improvement comprising: applying a gas pressure to said layer of inert gas; self-regulating the inert gas pressure in said layer; and self-regulating the liquid in said bath at a predetermined level by continuously passing the pressurized inert gas and quench liquid through a restricted pipe having an opening at said level.
Claim 3
Dependent Claim
12 words
The process as defined in claim 1, said gas pressure being constant.
Claim 4
Dependent Claim
11 words
The process as defined in claim 1, said gas being air.
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) | 1979-12-07 | 1980-06-07 | 1980-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-07 | 1984-06-07 | 1984-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-07 | 1988-06-07 | 1988-12-07 | $7700.00 | Window Closed / Lapsed |