Patent US3949115A successfully refreshed from Google Patents.
US3949115A
Expired / Lapsed
US
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Hollow filamentary structures
Assignee: Gun Ei Chemical Industry Co Ltd
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Filing: 1975-02-24
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Granted: 1976-04-06
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Expires: 1995-02-24
Abstract
Abstract A process for producing a hollow carbon or ion-exchange filament which comprises treating a filament consisting of a fiber-forming polymer of predominantly an uncured novolak resin composition with a curing reagent in the presence of a curing catalyst to effect the cure of the filament extending from the peripheral portion to the axial portion thereof to a depth of 20-90% of the cross-sectional area of the filament, removing the uncured core portion of the filament by extraction with a solvent, and then subjecting the resulting hollow novolak resin filament to a carbonization treatment or introducing an ion-exchangeable group into the resulting hollow novolak resin filament; and products produced by this process.
Inventors
- 👤 Yoshio Tamura
- 👤 Koichiro Ohtomo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:48
CPC Classifications
D; D06; D06M; D06M13/00; D06M13/322; D06M13/402; B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B01D69/00; B01D69/08; B01D71/00; B01D71/02; B01D71/021; B01D71/06; B01D71/72; B01J; B01J47/00; B01J47/12; B01J47/127; D01; D01F; D01F6/00; D01F6/58; D01F6/76; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/20; D01F9/24; D01F9/245; D01F9/26; D01F9/28; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2916; Y10T428/2918; Y10T428/2973; Y10T428/2975
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
57 words
A hollow carbon filament having adsorption activity, characterized in that said filament consists essentially of carbon; the hollow structure of the filament continuously extends in the axial direction of the filament; said filament has a degree of hollowness of 10 - 80%; and the surface area of said filament is at least 400 square meters per gram.
Claim 2
Dependent Claim
57 words
A hollow carbon filament having adsorption activity, characterized in that said filament consists essentially of carbon; the hollow structure of the filament continuously extends in the axial direction of the filament; said filament has a degree of hollowness of 10 - 80%; and the surface area of said filament is at least 400 square meters per gram.
Claim 3
Dependent Claim
23 words
The hollow carbon filament of claim 1 wherein said surface area is in the range of 500 - 1000 square meters per gram.
Claim 4
Dependent Claim
23 words
The hollow carbon filament of claim 1 wherein said surface area is in the range of 1000 - 3000 square meters per gram.
Claim 5
Dependent Claim
23 words
The hollow carbon filament of claim 3 wherein said surface area is in the range of 1500 - 2500 square meters per gram.
Claim 6
Dependent Claim
20 words
The hollow carbon filament of claim 1 wherein said degree of hollowness is in the range of 30 - 60%.
Claim 7
Dependent Claim
10 words
A filamentary structure derived from the filament of claim 1.
Claim 8
Dependent Claim
26 words
The filamentary structure of claim 6 wherein said structure is in a form selected from fibers, yarns, knit fabrics, woven fabrics, non-woven fabrics, felt, or matting.
References Cited (Backward Citations)
US3351484A
Cited
US3565749A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |