Patent US4185059A successfully refreshed from Google Patents.
US4185059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of hydrophilic fibres and filaments from synthetic polymers
Assignee: Bayer AG
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Filing: 1977-03-08
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Granted: 1980-01-22
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Expires: 1997-03-08
Abstract
Abstract The invention relates to a process for the production of hydrophilic filaments and fibers which comprises wet- or dry-spinning a fibre-forming synthetic polymer from a spinning solvent containing from 5 to 50% of a substance which has a higher melting or boiling point than the spinning solvent which is miscible with the spinning solvent and with a liquid suitable for use as a washing liquid and which is a non-solvent for the polymer to be spun and from 0,1 to 20% by weight of at least one substance which decomposes into a gas under heating.
Inventors
- 👤 Ulrich Reinehr
- 👤 Hermann-Josef Jungverdorben
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:04
CPC Classifications
D; D01; D01F; D01F1/00; D01F1/02; D01F1/10; D01F6/00; D01F6/44; D01F6/54; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2935
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
161 words
A process for the production of hydrophilic filaments and fibers having a sheath-core structure and a microporous core which comprises spinning a fiber-forming wet or dry spinnable synthetic polymer as a composition containing, in addition to the spinning solvent: (A) from 10 to 50% by weight, based on the spinning solvent and polymer solids content, of non-solvent for the polymer to be spun, which non-solvent (a) has a higher melting or boiling point under normal conditions than the spinning solvent, (b) is miscible with the spinning solvent and with a liquid suitable for use as a washing liquid, and (B) from 0.1 to 20% by weight, based on the polymer solids content, of at least one gas former which decomposes into a gas under heating; and washing said non-solvent from said filaments or fibers; in which said fibers or filaments are subjected to a temperature above the decomposition temperature of the gas former during spinning or in a subsequent treatment step.
Claim 2
Dependent Claim
161 words
A process for the production of hydrophilic filaments and fibers having a sheath-core structure and a microporous core which comprises spinning a fiber-forming wet or dry spinnable synthetic polymer as a composition containing, in addition to the spinning solvent: (A) from 10 to 50% by weight, based on the spinning solvent and polymer solids content, of non-solvent for the polymer to be spun, which non-solvent (a) has a higher melting or boiling point under normal conditions than the spinning solvent, (b) is miscible with the spinning solvent and with a liquid suitable for use as a washing liquid, and (B) from 0.1 to 20% by weight, based on the polymer solids content, of at least one gas former which decomposes into a gas under heating; and washing said non-solvent from said filaments or fibers; in which said fibers or filaments are subjected to a temperature above the decomposition temperature of the gas former during spinning or in a subsequent treatment step.
Claim 3
Dependent Claim
12 words
The process of claim 1, wherein said polymer is an acrylonitrile polymer.
Claim 4
Dependent Claim
18 words
The process of claim 2, wherein said acrylonitrile polymer comprises at least 50% by weight of acrylonitrile units.
Claim 5
Dependent Claim
18 words
The process of claim 1, wherein said gas former which decomposes into a gas is an ammonium salt.
Claim 6
Dependent Claim
12 words
The process of claim 4, wherein said ammonium salt is ammonium acetate.
Claim 7
Dependent Claim
24 words
The process of claim 1, wherein the spinning solvent contains from 0.1 to 10% by weight of (B) based on the polymer solids content.
Claim 8
Dependent Claim
28 words
The process of claim 1 wherein the spinning solvent contains from 10 to 20% by weight of (A), based on the weight of solvent and polymer solids content.
Claim 9
Dependent Claim
13 words
The process of claim 1 wherein (A) is glycerol or a homologue thereof.
Claim 10
Dependent Claim
23 words
The process of claim 1 in which the hydrophilic filament formed has an average pore size of one micron in the microporous core.
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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) | 1983-01-21 | 1983-07-23 | 1984-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-21 | 1987-07-23 | 1988-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-21 | 1991-07-23 | 1992-01-22 | $7700.00 | Window Closed / Lapsed |