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US4987030A Expired / Lapsed US ⏱️ 0.0 years remaining

High-tenacity conjugated fiber and process for preparation thereof

Assignee: Toray Industries Inc
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Filing: 1988-10-04
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Granted: 1991-01-22
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Expires: 2008-10-04
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Abstract

Abstract A conjugated fiber having a sheath-core conjugated structure comprising a polyester core component composed mainly of polyethylene terephthalate and a polyamide sheath component composed mainly of polyhexamethylene adipamide, is disclosed, which has excellent mechanical properties such as a high tenacity, a high modulus, and an improved dimensional stability, and an improved adhesion to a rubber, especially a high-temperature adhesion, an improved heat resistance in a rubber, and a high fatigue resistance, and thus is useful as an industrial material. By adopting a high-speed spinning procedure in the fiber preparing process, the peel resistance in the interface of the sheath-core conjugated structure is greatly improved, and the following valuable characteristics not possessed by conventional conjugated yarns can be obtained: (1) Excellent adhesion and high-temperature adhesion comparable to those of a polyamide, which cannot be obtained in a polyester. (2) High modulus and dimensional stability comparable to those of a polyester, which cannot be obtained in a polyamide. (3) A heat resistance in a rubber and a fatigue resistance superior to those of a polyester.

Inventors

  • 👤 Isoo Saito
  • 👤 Takuji Sato
  • 👤 Koichi Kubota
  • 👤 Masaharu Yamamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 16:55
CPC Classifications
D; D01; D01F; D01F8/00; D01F8/04; D01F8/12; D01F8/14; Y; Y10; Y10S; Y10S57/00; Y10S57/902; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2929; Y10T428/2931

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 258 words
A high-tenacity conjugated fiber having a sheath-core conjugated structure consisting essentially of a polyester composed mainly of ethylene terephthalate units as the core component and a polyamide as the sheath component, wherein the ratio of the core component to the sum of the core component and sheath component is 30 to 90% by weight, and the conjugated fiber has (a) a hynamic elasticity (E' 20 ) at 20° C. of at least 8×10 4 dyne/denier and a dynamic elasticity (E' 150 ) at 150° C. of at least 3×10 4 dyne/denier, as measured at 110 Hz, and a main dispersion peak temperature (Tα) of at least 140° C. in the mechanical loss tangent (tan δ) curve, (b) a creep rate (CR 20 ) not larger than 2.0% as measured at 20° C. after 48 hours' standing under a load of 1 g/denier and a creep rate (CR 150 ) not larger than 3.0% as measured at 150° C. after 48 hours' standing under a load of 1 g/denier, (c) an intrinsic viscosity ([η]) of at least 0.8 and a birefringence (Δn) of 160×10 -3 to 190×10 -3 in the polyester core component, (d) a sulfuric acid relative viscosity (ηr) of at least 2.8 and a birefringence (Δn) of at least 50×10 -3 in the polyamide sheath component, (e) a tenacity (T/D) of at least 7.5 g denier, (f) an initial modulus in tension (Mi) of at least 60 g/denier, and (g) a dry heat shrinkage (ΔS 150 ) as measured at 150° C. of not larger than 7%.
Claim 2
Dependent Claim 258 words
A high-tenacity conjugated fiber having a sheath-core conjugated structure consisting essentially of a polyester composed mainly of ethylene terephthalate units as the core component and a polyamide as the sheath component, wherein the ratio of the core component to the sum of the core component and sheath component is 30 to 90% by weight, and the conjugated fiber has (a) a hynamic elasticity (E' 20 ) at 20° C. of at least 8×10 4 dyne/denier and a dynamic elasticity (E' 150 ) at 150° C. of at least 3×10 4 dyne/denier, as measured at 110 Hz, and a main dispersion peak temperature (Tα) of at least 140° C. in the mechanical loss tangent (tan δ) curve, (b) a creep rate (CR 20 ) not larger than 2.0% as measured at 20° C. after 48 hours' standing under a load of 1 g/denier and a creep rate (CR 150 ) not larger than 3.0% as measured at 150° C. after 48 hours' standing under a load of 1 g/denier, (c) an intrinsic viscosity ([η]) of at least 0.8 and a birefringence (Δn) of 160×10 -3 to 190×10 -3 in the polyester core component, (d) a sulfuric acid relative viscosity (ηr) of at least 2.8 and a birefringence (Δn) of at least 50×10 -3 in the polyamide sheath component, (e) a tenacity (T/D) of at least 7.5 g denier, (f) an initial modulus in tension (Mi) of at least 60 g/denier, and (g) a dry heat shrinkage (ΔS 150 ) as measured at 150° C. of not larger than 7%.
Claim 3
Dependent Claim 41 words
A high-tenacity conjugated fiber as set forth in claim 1, wherein the polyester core component has a density (η) of at least 1.395 g/cm 3 and the polyamide sheath component has a density (η) of at least 1.135 g/cm 3 .
Claim 4
Dependent Claim 38 words
A high-tenacity conjugated fiber as set forth in claim 1, wherein the polyester core component has an initial modulus in tension (Mi) at least 90 g/denier and a terminal modulus in tension (Mt) not larger than 20 g/denier.
Claim 5
Dependent Claim 49 words
A high-tenacity conjugated fiber as set forth in claim 1, which has a tenacity (T/D) of at least 7.5 g/denier, an initial modulus in tension (Mi) of at least 60 g/denier, and a dry heat shrinkage (ΔS 150 ) as measured at 150° C. of not larger than 7%.

References Cited (Backward Citations)

US3975351A Cited
US4195052A Cited
US4504545A Cited
US4496630A Cited
US4851508A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-21 1994-07-23 1995-01-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-21 1998-07-23 1999-01-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-21 2002-07-23 2003-01-22 $7700.00 Window Closed / Lapsed

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