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US4359557A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing low pilling textile fiber and product of the process

Assignee: Eastman Chemical Co
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Filing: 1981-03-16
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Granted: 1982-11-16
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Expires: 2001-03-16
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Abstract

Abstract Process for manufacturing polyethylene terephthalate fibers having improved low-pilling properties by admixing ethylene glycol with polyethylene terephthalate polymer in extruder and holding the resulting processed fiber at constant length while heatsetting the fiber, and preferably relaxing the fiber up to about 5% while being heatset to a controlled length; and a polyester fiber as made by the process.

Inventors

  • 👤 Kenneth R. Watkins
  • 👤 Leron R. Dean

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 13:34
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/88; D01F6/92; C; C08; C08K; C08K5/00; C08K5/04; C08K5/05

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 138 words
A process for manufacturing polyethylene terephthalate fibers having improved low-pilling properties which comprise admixing in the feed throat of an extruder polyethylene terephthalate discrete solid polymer materials having an inherent viscosity of about 0.56 to about 0.60 with about 0.25% by weight ethylene glycol to form an admixture; melting in said extruder said solid polymer materials into a liquid and reacting said admixture to lower the inherent viscosity of said polyethylene terephthalate fibers to an inherent viscosity of about 0.39 to about 0.43, said inherent viscosity being determined by a concentration of 0.5% of the polymer in a solvent comprising 60% by weight phenol and 40% by weight tetrachloroethane, the polymer being dissolved at 125° C. and being measured at 25° C.; extruding the admixture into fibers; drafting the fibers; and heatsetting the fibers at a constant length.
Claim 2
Dependent Claim 138 words
A process for manufacturing polyethylene terephthalate fibers having improved low-pilling properties which comprise admixing in the feed throat of an extruder polyethylene terephthalate discrete solid polymer materials having an inherent viscosity of about 0.56 to about 0.60 with about 0.25% by weight ethylene glycol to form an admixture; melting in said extruder said solid polymer materials into a liquid and reacting said admixture to lower the inherent viscosity of said polyethylene terephthalate fibers to an inherent viscosity of about 0.39 to about 0.43, said inherent viscosity being determined by a concentration of 0.5% of the polymer in a solvent comprising 60% by weight phenol and 40% by weight tetrachloroethane, the polymer being dissolved at 125° C. and being measured at 25° C.; extruding the admixture into fibers; drafting the fibers; and heatsetting the fibers at a constant length.
Claim 3
Dependent Claim 21 words
A process as defined in claim 1, wherein said discrete solid polyethylene terephthalate polymer materials is in the form of pellets.
Claim 4
Dependent Claim 30 words
A process as defined in claim 1, wherein said fibers are heatset at constant length for about 90±5 seconds at a temperature of about 200° C. to about 215° C.
Claim 5
Dependent Claim 18 words
A process as defined in claim 1, wherein said fibers are drawn at a ratio of about 4:1.
Claim 6
Dependent Claim 23 words
A process as defined in claim 2, wherein said extruder is maintained at a temperature of about 265° C. to about 270° C.
Claim 7
Dependent Claim 30 words
A process as defined in claim 2, wherein said fibers are heatset at constant length for about 90±5 seconds at a temperature of about 200° C. to about 215° C.
Claim 8
Dependent Claim 18 words
A process as defined in claim 1, wherein said polyethylene terephthalate has an inherent viscosity of about 0.58.
Claim 9
Dependent Claim 16 words
A polyester fiber as made by the process of claim 1, said fiber being low pilling.
Claim 10
Dependent Claim 66 words
A polyester fiber as made by the process of claim 3, said fiber being low pilling, having a tenacity of about 3.5 to about 4.5 grams per denier, and an elongation of about 17% to about 27% and tenacity at 10% elongation of about 2.9 to about 3.5 grams per denier, and a shrinkage at 190° C. for 10 minutes of about 6% to about 8%.
Claim 11
Dependent Claim 23 words
A process as defined in claim 1, wherein said fibers are relaxed up to about 5% while being heatset to a controlled length.
Claim 12
Dependent Claim 23 words
A process as defined in claim 1, wherein said fibers are relaxed up to about 2.5% while being heatset to a controlled length.
Claim 13
Dependent Claim 31 words
A process as defined in claim 11 wherein said fibers are heatset to a controlled length for about 90±5 seconds at a temperature of about 200° C. to about 215° C.
Claim 14
Dependent Claim 21 words
A process as defined in claim 10, wherein said fibers are drawn at a ratio of about 3.9:1 to about 4.3:1.
Claim 15
Dependent Claim 21 words
A process as defined in claim 10, wherein said polyethylene terephthalate has an inherent viscosity of about 0.58 to about 0.60.
Claim 16
Dependent Claim 63 words
A polyester fiber as made by the process of claim 10, said fiber being low-pilling, having a tenacity of about 3.5 to about 4.65 grams per denier, an elongation of about 17% to about 27%, tenacity at 10% elongation of about 3.0 to about 3.95 grams per denier, and a shrinkage at 190° C. for 10 minutes of about 6% to about 8%.
Claim 17
Dependent Claim 64 words
A polyester fiber as made by the process of claim 10, said fiber being low pilling, having a tenacity of about 4.0 to about 4.5 grams per denier, an elongation of about 17% to about 27%, tenacity at 10% elongation of about 3.2 to about 3.7 grams per denier, and a shrinkage at 190° C. for 10 minutes of about 6% to about 8%.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-11-15 1986-05-17 1986-11-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-11-15 1990-05-17 1990-11-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-11-15 1994-05-17 1994-11-16 $7700.00 Window Closed / Lapsed

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