Conformable Microporous Fiber and Woven Fabrics Containing Same

Inactive Publication Date: 2015-03-19
WL GORE & ASSOC INC
View PDF12 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The present invention relates to a highly breathable and water-proof woven fabric made from ePTFE fibers. The ePTFE fibers are tightly woven into a fabric that is highly breathable and has a high water entry pressure. The fabric is also quieter, softer, and drapable. The high aspect ratio of the ePTFE fibers enables low weight per area fabric, easier and more efficient reshaping, and can achieve high water resistance in a woven fabric with low picks and ends per inch. The ePTFE fibers curl and / or fold upon themselves to conform to the weave spacing provided between the crossovers of the warp and weft fibers in the woven fabric. The woven fabrics constructed from the ePTFE fibers have a flat or substantially flat weave and a corresponding smooth surface.

Problems solved by technology

However, the addition of outer and inner fabric layers not only adds weight to an article of apparel, it also results in materials having the potential for a high water pick-up on the outer surface.
This may be detrimental in cases where the wearer is in a cold environment and the cold is transported to the body of the wearer.
In addition, water pick-up may lead to condensation on the inside of the garment, making the wearer feel wet.
Further, the color of the outer fabric may become discolored or darken upon water pick-up, thus reducing the aesthetic appearance of the garment.
Also, depending on the outer fabric, there may be a long dry time associated with the fabric itself, forcing the wearer to endure the disadvantages associated with the water pick-up for a longer time.
Additionally, because multifilament fibers are loosely packed for breathability in the fabric, water can undesirably fill the space between the fibers.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Conformable Microporous Fiber and Woven Fabrics Containing Same
  • Conformable Microporous Fiber and Woven Fabrics Containing Same
  • Conformable Microporous Fiber and Woven Fabrics Containing Same

Examples

Experimental program
Comparison scheme
Effect test

example 1a

[0145]A fine powder PTFE resin (Teflon 669 X, commercially available from E.I. du Pont de Nemours, Inc., Wilmington, Del.) was obtained. The resin was blended with Isopar® K in the ratio of 0.184 g / g by weight of powder. The lubricated powder was compressed in a cylinder and allowed to dwell at room temperature for 18 hours. The pellet was then ram extruded at a 169 to one reduction ratio to produce a tape of approximately 0.64 mm thick. The extruded tape was subsequently compressed to a thickness of 0.25 mm. The compressed tape was then stretched in the longitudinal direction between two banks of rolls. The speed ratio between the second bank of rolls and the first bank of rolls, hence the stretch ratio was 1.4:1 with a stretch rate of 30% / sec. The stretched tape was then restrained and dried at 200° C. The dry tape was then expanded between banks of heated rolls in a heated chamber at a temperature of 300° C. to a ratio of 1.02:1 at a stretch rate of 0.2% / sec, followed by an addit...

example 1b

[0151]A fluoroacrylate coating was applied to the woven fabric of Example 1a in order to render it oleophobic while preserving the porous and microporous structure.

[0152]The resulting oleophobic woven fabric had the following properties: thickness=0.20 mm, MVTR=21206 g / m2 / 24 hours, water pick-up=11 gsm, hand=131 g, tear strength=63.8 N, WEP=6.11 KPa, air permeability=1.72 cfm, and oil rating=6. A scanning electron micrograph of surface of the woven fabric taken at 150× magnification is shown in FIG. 5. A scanning electron micrograph of a side view of the fabric taken at 150× magnification is shown in FIG. 6. The length and width of the gaps between the fibers were less than 0.01 mm. The fabric had a weight of 158 g / m2.

example 1c

[0153]An amorphously locked ePTFE membrane was obtained having the following properties: thickness=0.04 mm, density=0.47 g / cc, matrix tensile strength in the strongest direction=105.8 MPa, matrix tensile strength in the direction orthogonal to the strongest direction=49.9 MPa, Gurley=16.2 s, MVTR=64168 g / m2 / 24 hours.

[0154]The woven fabric of Example 1b was laminated to the ePTFE membrane in the following manner. The fabric and the ePTFE membrane were bonded together by applying a dot pattern of a melted polyurethane adhesive to the membrane. While the polyurethane adhesive dots were molten, the fabric was positioned on top of the adhesive side of the membrane. This construct (article) was allowed to cool.

[0155]The resulting article had the following properties: thickness=0.22 mm, MVTR=12845 g / m2 / 24 hours, water pick-up=12 gsm, hand=196 g, tear strength=46.19 N, and oil rating=6. A scanning electron micrograph of the top surface of the article taken at 150× magnification is presented...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Lengthaaaaaaaaaa
Lengthaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to view more

Abstract

Expanded polytetrafluoroethylene (ePTFE) monofilament fibers and woven fabrics formed from the ePTFE fibers are provided. The ePTFE fibers have a substantially rectangular configuration, a density less than about 1.0 g / cc, and an aspect ratio greater than 15. Additionally, the ePTFE fibers are microporous and have a node and fibril structure. The ePTFE fiber may be woven into a fabric without first twisting the fiber. A polymer membrane and / or a textile may be laminated to the woven fabric to produce a laminated article. The ePTFE woven fabric simultaneously possesses high moisture vapor transmission (highly breathable) and high water entry pressure (water resistant). The woven fabric is quiet, soft, and drapable, making it especially suitable for use in garments, gloves and footwear applications. Treatments may be provided to the surface of the ePTFE fiber and / or the woven fabric to impart one or more desired functionality, such as, for example, oleophobicity.

Description

FIELD OF THE INVENTION[0001]The present invention relates generally to conformable microporous fibers, and more specifically, to conformable microporous fibers having a node and fibril structure that are highly breathable. Woven fabrics containing the conformable microporous fibers are also provided.BACKGROUND OF THE INVENTION[0002]Waterproof, breathable garments are well-known in the art. These garments are often constructed from multiple layers in which each layer adds a certain functionality. For example, a garment could be constructed using an outer textile layer, a waterproof, breathable film layer, and an inner textile layer. The outer and inner textile layers provide protection to the breathable film layer. However, the addition of outer and inner fabric layers not only adds weight to an article of apparel, it also results in materials having the potential for a high water pick-up on the outer surface. The pick-up of water by the outer fabric layer permits for thermal conduct...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): D03D15/00D03D15/58
CPCD03D15/0083D01D5/247D01D5/253D01F6/12D03D1/0035D03D13/008D06M13/236D06M2101/22D10B2501/04D10B2321/042D03D15/46A41D31/102Y10T442/227Y10T442/3106Y10T428/2922Y10T428/2935Y10T428/2975D10B2401/021D10B2501/041D10B2501/043A41D19/0006A43B7/125A41D2500/20D03D15/37D03D1/00D03D13/00
Inventor MINOR, DAVID J.MINOR, RAYMOND B.
Owner WL GORE & ASSOC INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap