Flame-resistant fiber blend, yarn, and fabric, and method for making same

Abstract

A fiber blend, a yarn spun from the fiber blend, and a fabric made from the yarn, wherein the fiber blend comprises: (a) about 40 wt.% to about 65 wt.% modacrylic fibers containing antimony, or FR acrylic fibers; (b) about 10 wt.% to about 50 wt.% cotton fibers or FR cotton fibers; (c) up to about 25 wt.% nylon fibers; and (d) greater than about 3 wt.% and less than 10 wt.% para-aramid fibers. The fabric is over 90 percent dyeable and is capable of achieving ASTM F1506 certification with an Arc Thermal Performance Value greater than 8.0 cal / cm2. The fabric is woven or knitted, and has a weight of about 4.0 oz. / yd.2 to about 10.5 oz. / yd.2. The fabric is suitable for garments worn during activities in which there is potential for exposure to flame and / or electrical arc.

Description

BACKGROUND OF THE INVENTION [0001] The present invention relates to flame-resistant fabrics woven or knitted from yarns that are made from fiber blends. [0002] Flame-resistant fabrics (also variously referred to as “fire-resistant”, “flame-retardant”, and “fire-retardant” fabrics) are fabrics that, once ignited, tend not to sustain a flame when the source of ignition is removed. A great deal of investigation and research has been directed toward the development and improvement of flame-resistant fabrics for use in various products such as bedding, clothing, and others. Flame-resistant clothing is often worn by workers involved in activities such as industrial manufacturing and processing, fire-fighting, electrical utility work, and other endeavors that entail a significant risk of being exposed to open flame and / or electrical arcs. [0003] Flame-resistant fabrics include both fabrics that are treated to be flame-resistant as well as flame-resistant fabrics made from inherently flame-...

AI Technical Summary

Benefits of technology

[0019] The fabric made in accordance with the invention has an advantageous combination of properties. The fabric is able to pass the ASTM F1506 specification, and in fact can achieve a char length of less than 5 inches, well under the 6-inch maximum permissible value according to the specification. Additionally, the fabric can achieve NFPA 70E Level II certification for protection against electrical arc exposure. This is achievable with relatively low fabric weights such that clothing made of the fabric is perceived as being comfortable to wear; the inclusion of cotton provides softness and moisture wicking, which further aids the comfort. Cotton also forms a char that assists in the flame-resistance performance. The nylon is included for durability and strength, as well as the ability to be thermoset for shrinkage. It has also been found that inclusion of nylon aids in improving the electrical arc protection. The para-aramid is included for its inherent flame-resistant properties, strength, and very low shrinkage even with repeated industrial launderings. The cotton content also allows the optional application of a resin to the fabric for further shrinkage control, if desired or needed in a particular instance. Furthermore, the fabric is over 90 percent dyeable such that dark, solid shades can be achieved.

Problems solved by technology

Flame-resistant clothing is often worn by workers involved in activities such as industrial manufacturing and processing, fire-fighting, electrical utility work, and other endeavors that entail a significant risk of being exposed to open flame and / or electrical arcs.

These types of fabrics are susceptible to losing their flame-resistance when laundered repeatedly because the flame-resistant composition tends to wash out.

However, the prior art known to the applicant does not disclose or suggest the specific fiber blend and fabric of the present invention, which has been found to possess distinct advantages and characteristics, including passage of ASTM F1506 and Level II certification for electrical arc protection.