ULTRAFINE POLYAMIDE FIBER, AND MELT-SPINNING METHOD AND DEVICE THEREFOR

• US 20130251992A1
• Filed: 11/21/2011
• Published: 09/26/2013
• Est. Priority Date: 11/29/2010
• Status: Abandoned Application

• Current Assignee: Toray Industries Incorporated
• Original Assignee: Toray Industries Incorporated
• Inventors: Kono, Takeaki, Kobayashi, Yasuki, Hanaoka, Jun
• Application Number:
  US13/989,140
• Publication Number:
  US 20130251992A1
• Time in Patent Office: Days
• US Class Current: 428/364
• CPC Class Codes: D01D 5/092 in shafts or chimneys
• CPC Class Codes: D01D 5/096 Humidity control, or oiling, of filaments, threads or the like, leaving the spinnerettes
• CPC Class Codes: D01F 6/60 from polyamides from polyamino acids or polypeptides D01F6/68
• CPC Class Codes: Y10T 428/2913 Rod, strand, filament or fiber

Abstract

Ultrafine polyamide fiber includes polyamide fiber with a single yarn fineness of 0.10 dtex or more and 0.50 dtex or less and an average number of 1.0 or less per 12,000 m of a filament in a length direction.

Claims

1-10. -10. (canceled)

11. Ultrafine polyamide fiber comprising polyamide fiber with a single yarn fineness of 0.10 dtex or more and 0.50 dtex or less and an average number of fuzzes of 1.0 or less per 12,000 m of a filament in a length direction.

12. The ultrafine polyamide fiber as defined in claim 11, wherein Uster unevenness in a filament in a length direction is 1.0% or less.

13. The ultrafine polyamide fiber as defined in claim 11, having a total fineness of 15 to 300 dtex and containing 30 or more filaments.

14. The ultrafine polyamide fiber as defined claim 12, having a total fineness of 15 to 300 dtex and containing 30 or more filaments.

15. The ultrafine polyamide fiber as defined in claim 11, wherein filaments have a modified cross section.

16. The ultrafine polyamide fiber as defined in claim 12, wherein filaments have a modified cross section.

17. The ultrafine polyamide fiber as defined in claim 13, wherein filaments have a modified cross section.

18. The ultrafine polyamide fiber as defined in claim 14, wherein filaments have a modified cross section.

19. The ultrafine polyamide fiber as defined in claim 11, wherein the single yarns contained in the ultrafine polyamide fiber have a circular filament cross section, orientation parameters of the single yarns with a circular cross section are such that a ratio of an orientation parameter of a surface portion of the single yarn to an orientation parameter of a central portion of the single yarn is 1.10 or more.

20. The ultrafine polyamide fiber as defined in claim 12, wherein the single yarns contained in the ultrafine polyamide fiber have a circular filament cross section, orientation parameters of the single yarns with a circular cross section are such that a ratio of an orientation parameter of a surface portion of the single yarn to an orientation parameter of a central portion of the single yarn is 1.10 or more.

21. The ultrafine polyamide fiber as defined in claim 13, wherein the single yarns contained in the ultrafine polyamide fiber have a circular filament cross section, orientation parameters of the single yarns with a circular cross section are such that a ratio of an orientation parameter of a surface portion of the single yarn to an orientation parameter of a central portion of the single yarn is 1.10 or more.

22. The ultrafine polyamide fiber as defined in claim 14, wherein the single yarns contained in the ultrafine polyamide fiber have a circular filament cross section, orientation parameters of the single yarns with a circular cross section are such that a ratio of an orientation parameter of a surface portion of the single yarn to an orientation parameter of a central portion of the single yarn is 1.10 or more.

23. A melt-spinning method for ultrafine polyamide fiber having a single yarn fineness of 0.10 dtex or more and 0.50 dtex or less and having an average of 1.0 or less fuzzes per 12,000 m in a length direction, wherein melt-spun yarns discharged from a spinning spinneret provided with discharge holes arranged circumferentially in the outer circumferential portion of the spinning spinneret are cooled by a cooling apparatus located below a central portion of the spinning spinneret and cool the melt-spun yarns by applying cooling air from either inside or outside of the melt-spun yarns discharged from the discharge holes, a finishing oil is supplied by a circular finishing oil supply apparatus having a disk-like guide portion located vertically below the cooling apparatus and that is in contact with the single yarns at its outer circumferential portion and also having a circular finishing oil-discharging slit located directly above the guide portion and arranged along the outer circumference of the guide and, subsequently, the yarns are bundled by a bundle-guide type finishing oil supply apparatus while receiving a second-stage finishing oil supply.

24. The method as defined in claim 23, wherein the cooling apparatus cools the melt-spun yarns by supplying cooling air from inside of the melt-spun yarns discharged from the discharge holes.

25. The method as defined in claim 23, wherein the cooling apparatus satisfies:

(1) distance (L) from a face of the spinning spinneret to a cooling start position of the cooling apparatus is as follows;

10 mm≦

L≦

70 mm, and

(2) cooling air provided at the cooling start position has a flow speed of 15 to 60 m/min.

26. The method as defined in claim 24, wherein the cooling apparatus satisfies:

(1) distance (L) from a face of the spinning spinneret to a cooling start position of the cooling apparatus is as follows;

10 mm≦

L≦

70 mm, and

(2) cooling air provided at the cooling start position has a flow speed of 15 to 60 m/min.

27. A melting spinning apparatus that produces ultrafine polyamide fiber having a single yarn fineness of 0.10 dtex or more and 0.50 dtex or less and having an average of 1.0 or less fuzzes per 12,000 m in a length direction, comprises:

a spinning spinneret provided with discharge holes arranged circumferentially in an outer circumferential portion of the spinning spinneret, and a cooling apparatus located below a central portion of the spinning spinneret and cools the melt-spun yarns by applying cooling air from inside or outside of the melt-spun yarns discharged from the discharge holes, and

a circular finishing oil supply apparatus having a disk-like guide portion located vertically below the cooling apparatus and in contact with the single yarns at an outer-circumferential portion, a circular finishing oil-discharging slit located directly above the guide portion and arranged along an outer circumference of the guide, and a bundle-guide type finishing oil supply apparatus located thereunder and intended to bundle the yarns while performing a second-stage finishing oil supply.

28. The melt-spinning apparatus for ultrafine polyamide fiber as defined in claim 27, wherein the cooling apparatus cools the melt-spun yarns by supplying cooling air from inside of the melt-spun yarns discharged from the discharge holes.