US3143584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spinning polypropylenes which have been subjected to thermal degradation promoted bythe presence of sulfur compounds
Assignee: Imperial Chemical Industries Ltd
•
Filing: 1962-03-15
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Granted: 1964-08-04
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Expires: 1982-03-15
Abstract
No abstract record available.
Inventors
- 👤 Roberts John Francis Lloyd
- 👤 Walker Eric
- 👤 Scott Gerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:14
CPC Classifications
D; D01; D01F; D01F1/00; D01F1/02; D01F1/10; C; C08; C08F; C08F8/00; C08F8/50; D01F6/00; D01F6/02; D01F6/04; D01F6/06; C08F2810/00; C08F2810/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
A PROCESS FOR THE PRODUCTION OF FIBERS AND FILAMENTS OF POLYPROPYLENE HAVING GREATLY IMPROVED TENACTIY WHICH COMPRISES SUBJECTING ISOTATIC POLYPROPYLENE HAVING AN INTRINSIC VISCOSITY GREATER THAN 2 TO THERMAL DEGRADATION AT A TEMPERATUR ABOVE ABOUT 240*C. PROMOTED BY THE PRESENCE OF A SULFUR COMPOUND WHICH GIVES RISE TO THIYL RADICALS, MELT SPINNING THE RESULTANT POLYMER TO YIELD FILAMENTS HAVING AN INTRINSIC VISCOSITY GREATER THAN 0.5 AND A BRIEFRINGENCE OF LESSS THAN 10X10**3 AND DRAWING THE FILAMENTS AT A RATIO OF AT LEAST 2 TO 1.
Claim 2
Dependent Claim
85 words
A PROCESS FOR THE PRODUCTION OF FIBERS AND FILAMENTS OF POLYPROPYLENE HAVING GREATLY IMPROVED TENACTIY WHICH COMPRISES SUBJECTING ISOTATIC POLYPROPYLENE HAVING AN INTRINSIC VISCOSITY GREATER THAN 2 TO THERMAL DEGRADATION AT A TEMPERATUR ABOVE ABOUT 240*C. PROMOTED BY THE PRESENCE OF A SULFUR COMPOUND WHICH GIVES RISE TO THIYL RADICALS, MELT SPINNING THE RESULTANT POLYMER TO YIELD FILAMENTS HAVING AN INTRINSIC VISCOSITY GREATER THAN 0.5 AND A BRIEFRINGENCE OF LESSS THAN 10X10**3 AND DRAWING THE FILAMENTS AT A RATIO OF AT LEAST 2 TO 1.
References Cited (Backward Citations)
US2727879A
Cited
US3013003A
Cited
US2953542A
Cited
US2995539A
Cited
US2967847A
Cited
US2967845A
Cited
US2967848A
Cited
US2967849A
Cited
US2967850A
Cited
US3010937A
Cited
US2960538A
Cited
US3006885A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-08-04 | 1968-02-03 | 1968-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-08-04 | 1972-02-03 | 1972-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-08-04 | 1976-02-03 | 1976-08-04 | $7700.00 | Window Closed / Lapsed |