US4826949A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High shrinkage polyester fibers and method of preparation
Assignee: BASF Corp
•
Filing: 1987-12-22
•
Granted: 1989-05-02
•
Expires: 2007-12-22
Abstract
Abstract High shrinkage polyester fibers having good strength and uniform dyeability are disclosed, along with a method of producing the high shrinkage polyester fibers, by drawing a feeder yarn having a birefringence (Δn) of at least 0.0175 at ambient temperature and carefully controlled draw ratios.
Inventors
- 👤 Wayne S. Stanko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:40
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/62
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
60 words
A yarn comprising polyester filaments consisting essentially of poly(ethylene terephthalate), said filaments characterized by: (i) a boiling water shrinkage of at least 40%; (ii) an amount of crystallization of from about 15 to about 20%; (iii) a tenacity in the range of from about 4.0 to 5.0 grams per denier; and (iv) a long-period spacing of greater than 225 Å.
Claim 2
Dependent Claim
60 words
A yarn comprising polyester filaments consisting essentially of poly(ethylene terephthalate), said filaments characterized by: (i) a boiling water shrinkage of at least 40%; (ii) an amount of crystallization of from about 15 to about 20%; (iii) a tenacity in the range of from about 4.0 to 5.0 grams per denier; and (iv) a long-period spacing of greater than 225 Å.
Claim 3
Dependent Claim
35 words
The yarn recited in claim 1 wherein said filaments have an average crystal size in the range of from about 25 to about 30 Å as measured in the direction of the fiber axis (105).
Claim 4
Dependent Claim
15 words
The yarn recited in claim 1 wherein said filaments have a birefringence of about 0.1444.
References Cited (Backward Citations)
US4442057A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-01 | 1992-10-31 | 1993-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-01 | 1996-10-31 | 1997-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-01 | 2000-10-31 | 2001-05-02 | $7700.00 | Window Closed / Lapsed |