Lyocell nonwoven fabric

• US 7,067,444 B2
• Filed: 03/28/2002
• Issued: 06/27/2006
• Est. Priority Date: 08/23/1996
• Status: Expired due to Fees

• Current Assignee: International Paper Company
• Original Assignee: Weyerhaeuser Company (Weyerhauser)
• Inventors: Luo, Mengkui, Jewell, Richard A., Neogi, Amar N., Roscelli, Vincent A.
• Primary Examiner(s): EINSMANN, MARGARET V
• Application Number:
  US10/109,722
• Publication Number:
  US 20020148050A1
• Time in Patent Office: 1,552 Days
• Field of Search: 428/369, 428/399, 428/400, 811/551, 264/196, 264/203, 442334-337, 442/340
• US Class Current: 442/337
• CPC Class Codes: D01D 5/098 with simultaneous stretching
• CPC Class Codes: D01D 5/14 with flowing liquid or gaseous stretching media , e.g. solution-blowing
• CPC Class Codes: D01D 5/18 by means of rotating spinnerets
• CPC Class Codes: D01F 2/00 Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
• CPC Class Codes: D21C 3/02 with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
• CPC Class Codes: D21C 9/004 inorganic compounds
• CPC Class Codes: D21C 9/10 Bleaching ; Apparatus therefor
• CPC Class Codes: Y10T 428/2922 Nonlinear [e.g., crimped, coiled, etc.]
• CPC Class Codes: Y10T 428/2924 Composite
• CPC Class Codes: Y10T 428/2929 Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type]
• CPC Class Codes: Y10T 428/2976 Longitudinally varying
• CPC Class Codes: Y10T 428/2978 Surface characteristic
• CPC Class Codes: Y10T 442/60 Nonwoven fabric [i.e., nonwoven strand or fiber material]
• CPC Class Codes: Y10T 442/608 Including strand or fiber material which is of specific structural definition
• CPC Class Codes: Y10T 442/61 Cross-sectional configuration varies longitudinally along strand or fiber material
• CPC Class Codes: Y10T 442/611 Cross-sectional configuration of strand or fiber material is other than circular
• CPC Class Codes: Y10T 442/614 Strand or fiber material specified as having microdimensions [i.e., microfiber]

Abstract

A lyocell nonwoven fabric having fibers characterized by pebbled surfaces and variable cross sections and diameters along the fibers and from fiber to fiber, is disclosed. The lyocell nonwoven fabric is produced by centrifugal spinning, melt blowing or spunbonding. The lyocell nonwoven fabric has fibers that can be made in the microdenier range with average weights as low as one denier or less. The lyocell nonwoven fabric has fibers with low gloss, a reduced tendency to fibrillate and have enhanced dye receptivity.

Claims

1. A lyocell nonwoven fabric comprising fibers characterized by a greater variability in cross-sectional diameters and cross-sectional configurations along the fiber length and from fiber to fiber as compared to the variability in cross-sectional diameters and cross-sectional configurations along the fiber length and from fiber to fiber of continuously drawn fibers.

2. The lyocell nonwoven fabric of claim 1 comprising fibers having a pebbled surface.

3. The lyocell nonwoven fabric of claim 1 comprising fibers having an irregular crimp with an amplitude greater than about 1 fiber diameter and a period greater than about 5 fiber diameters.

4. The lyocell nonwoven fabric of claim 1 having a low tendency to fibrillate under conditions of wet abrasion and having enhanced dye receptivity.

5. A lyocell nonwoven fabric comprising fibers having an average denier less than 0.45.

6. A lyocell nonwoven fabric comprising continuous meltblown fibers.

7. A lyocell nonwoven fabric formed by depositing a multiplicity of strands of a cellulose solution on a receiving surface and then regenerating the cellulose.

8. The lyocell nonwoven fabric of claim 7, in which the fibers are self-bonded.

9. The lyocell nonwoven fabric of claim 7 in which the fibers are bonded by a method consisting of hydroentangling, adhesive binders, and by combinations of these methods.

10. A lyocell nonwoven fabric formed by meltblowing continuous lyocell filaments.

11. A lyocell nonwoven fabric formed by centrifugal spinning.

12. A lyocell nonwoven fabric formed by spun bonding.