US4814222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aramid fibers with improved flame resistance
Assignee: Southern Mills Inc
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Filing: 1988-02-04
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Granted: 1989-03-21
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Expires: 2008-02-04
Abstract
Abstract The flame-resistant properties of aramid fibers are improved using a swelling agent to introduce a flame retardant into the fiber. The treated fiber has properties of strength approximating the untreated fiber, flame resistance greater than the untreated fiber and is conveniently dyed to an unlimited range of colors with high color yield. An aqueous dimethylsulfoxide solution is used as the swelling agent.
Inventors
- 👤 James K. Davis
- 👤 Barbara J. Cates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:36
CPC Classifications
D; D06; D06P; D06P3/00; D06P3/02; D06P3/04; D06P3/24; D06P1/00; D06P1/90; D06P1/92; D06P1/922; D06P1/926; D06P1/928; Y; Y10; Y10S; Y10S428/00; Y10S428/92; Y10S8/00; Y10S8/92; Y10S8/924; Y10S8/925; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2964; Y10T428/2967; Y10T428/2969; Y10T442/00; Y10T442/20; Y10T442/2631; Y10T442/2721
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
75 words
An aramid fabric which has been sequentially treated with a flame retardant, dyed in the presence of an organic swelling agent-solvent and heated to fix the flame retardant and dye therein consisting essentially of poly(m-phenyleneisophthaliamide) fibers containing within the fiber after at least 25 launderings an amount of flame retardant sufficient to impart a Limiting Oxygen Index of at least 0.30 and a breaking strength at least 80% of that of an untreated, undyed fabric.
Claim 2
Dependent Claim
75 words
An aramid fabric which has been sequentially treated with a flame retardant, dyed in the presence of an organic swelling agent-solvent and heated to fix the flame retardant and dye therein consisting essentially of poly(m-phenyleneisophthaliamide) fibers containing within the fiber after at least 25 launderings an amount of flame retardant sufficient to impart a Limiting Oxygen Index of at least 0.30 and a breaking strength at least 80% of that of an untreated, undyed fabric.
Claim 3
Dependent Claim
14 words
The fabric of claim 1 having a Limiting Oxygen Index of at least 0.35.
Claim 4
Dependent Claim
14 words
The fabric of claim 2 having a Limiting Oxygen Index of at least 0.40.
References Cited (Backward Citations)
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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) | 1992-03-20 | 1992-09-19 | 1993-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-20 | 1996-09-19 | 1997-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-20 | 2000-09-19 | 2001-03-21 | $7700.00 | Window Closed / Lapsed |