FIRE AND ABRASION RESISTANT YARN

Abstract

A method and system for forming fire and abrasion resistant yarns is disclosed. The fire and abrasion resistant yarn includes a fibrous bundle spun from a blend of fire retardant fibers and non-fire retardant fibers. The fibrous bundle is wrapped and integrated with a filament comprising a fire retardant (FR) material, and which is introduced during spinning of the fibers of the fibrous bundle so as to be wrapped about and help bind the fibrous bundle. The FR filament will be selected from fire/heat resistant and abrasion resistant materials, while the fibers of the fibrous bundle can be selected from natural or synthetic fibers or filaments having additional desired properties.

Claims

1. A method of making a fire and abrasion resistant yarn, comprising: spinning a series of fibers to form a fibrous bundle, the series of staple fibers comprising a blend of fire retardant fibers and non-fire retardant fibers; and introducing a fire resistant filament during spinning of the series of fibers, wherein the fire resistant filament is applied at approximately the same turns per inch as the series of fibers, and is wrapped about and substantially embedded in an outer circumference of the fibrous bundle to form the fire and abrasion resistant yarn.

2. The method of claim 1, wherein the series of fibers and the fire resistant filament are spun in a first twist direction.

3. The method of claim 1, wherein the fibrous bundle defines a fibrous core of the yarn, and further comprising: plying at least one additional filament or an additional yarn to the fibrous core, and spinning the at least one additional filament or additional yarn in a second twist direction opposite the first twist direction.

4. The method of claim 1, wherein the series of fibers comprise fibers including materials selected from a group comprising para-aramids, Meta-aramids, modacrylics, vectran, polybenzimidazole (PBI), polybenzoxazole (PBO), opan, acrylic, acetate, pyrotex, Teflon, kynol, rayon, wool, Tencel, nylon, polyester, cotton, and blends thereof.

5. The method of claim 1, wherein the fire resistant filament comprises a material selected from a group comprising nylon, polyester, para-aramid, polypropylene, PTT, polyethylene, meta-aramid, liquid crystal polymers, and combinations thereof.

6. The method of claim 1, wherein a mass ratio of the first filament to the spun series of fibers is between about 6% and about 83% by weight

7. The method of claim 1, wherein the fibrous bundle comprises a blend of 35% to 65% modacrylic or fibers and approximately 65% to 35% by weight of fibers selected from the group comprising cotton, rayon, wool, and/or blends thereof, and wherein the first filament comprises FR nylon.

8. The method of claim 6, wherein the fire and abrasion resistant yarn comprises a ring spun yarn comprising about 25% to 45% FR nylon, about 30% to 40% modacrylic fibers, and about 25% to 35% cotton fibers by weight.

9. A fire and abrasion resistant fabric knitted ow woven from the fire and abrasion resistant yarn produced according to the method of claim 1.

10. The fire and abrasion resistant fabric of claim 9, wherein the fabric comprises a vertical flame resistance of at least approximately 25.0 seconds (after flame) and a char length of less than 4.5 inches measured according to ASTM 6413.

11. The fire and abrasion resistant fabric of claim 9 wherein the fabric comprises a thermal shrinkage of less than approximately 5% in length and less than approximately 5% in width.

12. A fire and abrasion resistant yarn, comprising: a fibrous bundle including a series of staple fibers spun in a first direction defining a core; a fire resistant filament introduced during spinning of the fibers forming the fibrous bundle, the fire resistant filament comprising a fire retardant material, and wherein the fire resistant filament is introduced and spun at approximately the same turns per inch as the staple fibers of the fibrous bundle, filament is wrapped about and substantially embedded within an outer circumference of the fibrous bundle.

13. The fire and abrasion resistant composite yarn of claim 12, further comprising at least one additional filament or an additional yarn spun about the embedded fire resistant filament and fibrous bundle to form a composite yarn bundle.

14. The fire and abrasion resistant composite yarn of claim 13, wherein the at least one additional filament is spun in a second twist direction opposite the first twist direction.

15. The fire and abrasion resistant composite yarn of claim 12, wherein the fire resistant filament and the fibrous bundle are substantially intermingled or embedded during spinning to substantially incorporate the fire resistant filament within the fibrous bundle.

16. The fire and abrasion resistant composite yarn of claim 12, wherein the series of fibers comprises fibers including a material selected from a group comprising para-aramids, Meta-aramids, modacrylics, vectran, acetate, acrylic, polypropylene, polybenzimidazole (PBI), polybenzoxazole (PBO), opan, pyrotex, Teflon, kynol, rayon, FR rayon, Tencel, nylon, FR nylon, polyester, cotton, and blends thereof.

17. The fire and abrasion resistant yarn of claim 12, wherein the fire resistant filament comprises a material selected from a group comprising nylon, polyester, PTT, para-aramid, glass, and blends thereof.

18. The fire and abrasion resistant yarn of claim 12, wherein a mass ratio of the fire resistant filament to the fibrous bundle is between about 6% and about 83% by weight.

19. The fire and abrasion resistant yarn of claim 12, wherein the fibrous bundle comprises a blend of 35% to 65% modacrylic and 65% to 35% cotton by weight, and the first filament comprises FR nylon.

20. The fire and abrasion resistant yarn of claim 12, comprising a blend of 30% to 45% FR nylon, 30% to 40% modacrylic, and 25% to 35% cotton by weight.

21. The fire and abrasion resistant yarn of claim 10, wherein a fabric formed from the composite yarn is used in protective apparel for heat and abrasion protection.

22. The fire resistant yarn of claim 19, wherein the fabric comprises woven or knitted construction.

23. The yarn of claim 22, wherein the fabric comprises a pattern selected from a group comprising a plain pattern, a twill pattern, a basket pattern, a satin pattern, a leno pattern, a crepe pattern, a dobby pattern, a herringbone pattern, a Jacquard pattern, a pique pattern, a warp pile, and a weave configuration.

24. The fire and abrasion resistant fabric of claim 22, wherein the fabric comprises a vertical flame resistance of at least approximately 25.0 seconds (after flame) and a char length of less than 4.5 inches measured according to ASTM 6413.

25. The fire and abrasion resistant fabric of claim 22, wherein the fabric comprises a thermal shrinkage of less than approximately 5% in length and less than approximately 5% in width.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0014] It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the Figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements. Embodiments incorporating teachings of the present disclosure are shown and described with respect to the drawings herein, in which:

[0015] FIG. 1 provides a schematic illustration of a system and a method for making a fire and abrasion resistant composite yarn, according to an embodiment of the disclosure;

[0016] FIG. 2 illustrates another example system and method for making a fire and abrasion resistant composite yarn, according to an embodiment of the disclosure;

[0017] FIG. 3 illustrates an example of a fire and abrasion resistant composite yarn, according to the principles of the disclosure;

[0018] The use of the same reference symbols in different drawings indicates similar or identical items.

DETAILED DESCRIPTION

[0019] The following description in combination with the Figures is provided to assist in understanding the teachings disclosed herein. The description is focused on specific implementations and embodiments of the teachings, and is provided to assist in describing the teachings. This focus should not be interpreted as a limitation on the scope or applicability of the teachings.

[0020] In general, the present invention is directed to systems and methods for formation of fire resistant and abrasion resistant composite spun yarns. In addition, these fire and abrasion resistant composite yarns will generally exhibit additional properties such as enhanced strength, moisture-wicking and comfort, as well as being easily knitted or woven to form lightweight flame/fire and abrasion resistant fabrics. Some of the embodiments of the present disclosure contain processes that help impart useful performance properties to the finished fire resistant composite yarns. These performance properties may then be imparted to fabrics made of such composite yarns and the garments formed therefrom. In general, the yarns of the present invention are designed to be produced using a ring or other type of spinning frame and spinning process.

[0021] The finished yarns formed by these processes further generally are designed to endure the mechanical and physical abuses of knitting or weaving machinery without sustaining physical damage during knitting or weaving of the yarns into lightweight, economically produced fabrics or for application of the yarns, as well as during other operations such as braiding, stitch bonding, tufting, etc. . . . for forming various woven and/or non-woven performance fabrics. The resultant fire and abrasion resistant fabrics formed from the composite yarns will be lightweight and flexible with softness and other properties, while also incorporating enhanced performance properties such as increased strength, abrasion resistance and fire/flame resistance.

[0022] Such fabrics can be used in forming garments such as military uniforms or firefighters' coats, protective gloves, arc flash protection or a variety of other type of garments and articles for which properties such as enhanced flame/fire or heat resistance and abrasion resistance, enhanced strength, but also will have further desired properties such as softness or feel to enable enhanced mobility and/or flexibility of the fabrics.

[0023] FIG. 1 illustrates an example embodiment of a system and process 100 for making a fire and abrasion resistant composite yarn 122, in accordance with an embodiment of the disclosure. The system generally will utilize a spinning frame 120, and the process includes introducing a series of fibers 102 from at least one roving 103 to a series of drafting rolls 105 of the spinning frame 120 and spinning the series of fibers 102 to form a fibrous bundle 107. While FIG. 1 shows a single roving 103 supplying fibers 102, a single roving can be used to supply fibers or multiple (i.e., two, three, four, etc. . . . ) rovings also can be used, such as indicated in FIG. 2. The spinning frame 120 may include a spinning frame that can form a part of a ring spinning process.

[0024] The series of fibers 102 forming the fibrous bundle 107 can include a blend of fire or flame resistant (FR) fibers such as modacrylic fibers, and non-fire or flame resistant (Non-FR) fibers such as cotton and other staple fibers. The FR fibers may provide resistance to fire propagation in the fibrous bundle 107 when exposed to a flame, while fibers such as cotton and other staple fibers may provide additional properties such as moisture wicking, softness, etc. in addition to providing flame resistance. In some embodiments, the fibers 102 may include fibers selected from a group including para-aramids, Meta-aramids, modacrylics, liquid crystal polymers such as Vectran™ polybenzimidazole (PBI), polybenzoxazole (PBO), opan, pyrotex, Teflon, kynol, rayon, FR rayon, Tencel, nylon, FR nylon, acetate, acrylic, polyester, cotton, and blends thereof.

[0025] Referring again to FIG. 1, a fire retardant (FR) filament 108 will be introduced to the initial spinning operation 120, being fed into the drafting zone 106 wherein the series of fibers 102 are spun together. The FR filament 108 further generally is applied at approximately the same turns per inch as that of the series of fibers 102 so that the first filament is integrated with the fibrous bundle 107, being combined and/or intermingled with the fibers of the fibrous bundle to form an integrated fibrous bundle 107 as it exits the spinning frame. In addition, during spinning the FR filament 108 is helically wrapped around the fibrous bundle 107, with the spun fibers defining a core of an initial or base yarn 112 that is bound by the helical wrapping and integration of the FR filament 108 about/with the fibrous bundle.

[0026] In an embodiment, the FR filament 108 can be introduced to the side of the fibrous bundle 107 before or as the fibrous bundle exits the initial spinning frame 120. Introducing the FR filament in this manner causes the FR filament 108 to integrate with the series of fibers 102 as they are spun into the fibrous bundle, i.e., mixing to substantially bind the FR filament about the series of spun fibers 102, the FR filament is helically wrapped about and embedded as an integral component integrated with the fibers about the outer circumference of the resulting composite yarn 122.

[0027] The FR filament 108 includes a fire resistant material that further has a high abrasion resistance, such as, for example, flame resistant (FR) Nylon. Other flame resistant filaments forming the first filament may include FR rayon, FR para-aramids, FR polyester, meta-aramid, polypropolene, liquid crystal polymers such as Vectran™, FR PTT, FR polyethylene. Other materials that may be inherently abrasion resistant also can be used, and a flame or fire retardant may be added therein to improve their fire resistance.

[0028] The helical wrapping and incorporation of the FR filament around/into the fibrous bundle helps integrate the FR properties of the FR filament into the fibrous bundle, such when the composite yarn or a fabric made from the composite yarn is introduced to a fire/flame or to intense heat, it will shrink and contract about the fibrous bundle. The tightening of the FR filament about the fibrous bundle will deprive the fibers of the fibrous bundle of oxygen therebetween. When fibers of the yarn 112 are deprived of oxygen, the Limiting Oxygen Index (LOI) of the yarn 112 (and thus fabrics formed therefrom) increases.

[0029] However, the shrinkage that occurs upon exposure of the yarn to fire/flame or intense heat will be substantially minimized due to the FR filament being helically wrapped around and integrated with the fibrous bundle 107 during spinning, rather than the filament being applied/running along the axis of the fibrous bundle. As a result, the FR fibers with which the FR filament is embedded help protect the FR filament from degradation and collapse, enabling a controlled, limited shrinkage of the FR filament around the fibrous bundle so that it becomes more tightly integrated with the fibrous bundle, without collapsing, resulting in a stronger fire and abrasion resistant composite yarn and fabrics made therefrom with increased fire resistance.

[0030] The fire and abrasion resistant composite yarn formed from the integrated filament 108 and fibrous bundle 107 generally is spun with a twist in a first direction. In an embodiment, the first direction of twist can be a S-direction or counter-clockwise direction of twist. In another embodiment, the first direction of twist can be a Z-direction or clock-wise direction of twist. As the yarn 112 exits the initial spinning operation 120, the yarn 112 may be plied with an additional yarn bundle or filament 110, as indicated in FIG. 2, or can be doubled and during an additional spinning operation, being spun in a second twist direction opposite to the first twist direction (e.g. an opposite Z or S twist) for a number of turns or twists per inch designed to substantially neutralize and/or balance the torque of the finished composite yarn 122.

[0031] For example, in an embodiment, a base fire resistant composite yarn 112 can be formed as a ring spun yarn with a mass ratio of the FR filament to the fibers of the composite yarn of between about 6% and about 83%, although such mass ratio ranges are example ranges, and different mass ratio ranges may be considered to meet certain desired characteristics of the resultant composite yarn. The yarn can include a fibrous bundle of spun modacrylic and cotton fibers, spun with an approximately 20-100 denier FR nylon filament wrapped/applied about the fibrous bundle with a Z-twist during an initial spinning process. Thereafter, the yarn can be doubled and twisted in an opposite direction (e.g. with an S-twist) during a subsequent twisting process such as indicated at 130 of FIG. 1. The twisting of the doubled yarn in the second twist direction opposite the first twist direction to substantially minimize the torque in the resultant fire and abrasion resistant composite yarn 122.

[0032] In a further example embodiment, the fibrous bundle can comprise a blend of about 35% to 65% modacrylic by weight and about 65% to 35% cotton by weight, spun with an approximately 70 denier FR Nylon filament forming about 25%-38% by weight of the yarn. Other embodiments can include varying types of FR and non-FR fibers in varying weight/mass percentages, as well as varying the size of the FR filament. For example, a blend of 35% to 45% FR nylon filament ranging in size from about 20 denier to upwards of about 70-100 denier, 30% to 40% modacrylic, and 25% to 35% cotton can be used with the finished fire and abrasion resistant composite yarn comprising an approximately 20Ne ring spun yarn including a blend of about 35%-37% FR Nylon, 33%-35% FR modacrylic fibers, and 26%-28% cotton. These mass/weight ratio ranges are example ranges, and different weight/mass ratio ranges may be considered to meet fire resistance and abrasion resistance as desired in the resultant composite yarn.

[0033] As described with reference to FIG. 2a, the series of fibers 102 can include a blend of fire or flame resistant (FR) fibers, which can include modacrylic fibers, FR rayon, fire resistant treated cotton, wool, and other, similar fibers; as well as a series of non-fire or non-flame resistant (Non-FR) fibers including staple fibers such as cotton, wool, viscose fibers, and other similar fibers. For example, the fibers 102 can include para-aramids, Meta-aramids, modacrylics, vectran, polybenzimidazole (PBI), polybenzoxazole (PBO), opan, pyrotex, Teflon, kynol, rayon, wool, Tencel, nylon, polyester, cotton, and blends thereof. The FR fibers may provide resistance to fire propagation in the fibrous bundle when exposed to a flame. Fibers such as cotton fibers may provide additional properties such as moisture wicking, softness, etc. in addition to providing flame resistance. The series of fibers 102 will be spun together forming a fibrous bundle 107 that can in effect, define a core or centralized bundle of the composite yarn. A first filament 108 further will be introduced during the spinning operation, with the first filament being helically wound about the outer circumference of the fibrous bundle and embedded with the fibers thereof.

[0034] The first filament will include a fire resistant material with high abrasion resistance, such as, for example, flame resistant (FR) Nylon. Other flame resistant filaments forming the first filament may include FR PTT, Teflon, FR para-aramids, FR polyester. While these materials may be inherently abrasion resistant, a flame or fire retardant may be added therein to improve their fire resistance. For example, other materials for the first filament can include polyester, nylon, lycra, para-aramids, high density polyethylene and blends thereof.

[0035] The first filament is introduced to the initial spinning operation 120 with the series of fibers 102, generally being fed into the drafting zone 106 with the fibers such that the first filament is combined and/or intermingled with the series of fibers 102 of the fibrous bundle being helically spun or twisted thereabout to form an integrated filament/fibrous bundle. In an embodiment, the first filament can be introduced to the fiber bundle, for example, from the side as indicated in FIG. 2, before or as the fibrous bundle is being formed or as it exits the initial spinning operation 120.

[0036] Introducing the first filament 108 in this manner causes the first filament to integrate with the series of fibers 102 to form the integrated filament/fibrous bundle 107 with the staple fibers locked substantially within a middle or center portion of the integrated filament/fibrous bundle. The first filament 108 thus becomes embedded in the surface as a substantially integral component in the resulting base yarn. As further illustrated in FIG. 2, the base yarn 112 also can be spun twisted with a second filament or another yarn 110 to integrate additional properties such as cut resistance, etc. . . . to the resultant composite yarn 122, and/or to provide further strength and protection when the fire and abrasion resistant composite yarn 122 is subjected to mechanical stresses during knitting, weaving, etc. to form fabrics.

[0037] The resultant fire and abrasion composite resistant yarns 122 is thus formed with a fibrous bundle having a blend of fibers such as cotton, modacrylics, and/or other blends of FR and/or Non-FR fibers that are bound about an outer circumference thereof with the FR nylon filament (e.g. a approximately 20 denier to approximately 70-100 denier FR nylon filament). The fibrous bundle supplies comfort and FR properties to the composite yarn, while the FR nylon filament wrapped about the outer circumference of the fibrous bundle adds abrasion resistance to the surface of the yarn/fabric where needed most for abrasion resistance. The tight wrapping of the FR nylon filament also helps control shrinkage of the yarn upon exposure to flame or high heat, enabling the filament to shrink about the fibrous bundle of cotton and modacrylic sufficient to close any voids and limit the oxygen within the yarn, without excessive shrinkage or collapse of the yarn.

[0038] As noted, fire and abrasion resistant fabrics can be made from the fire resistant composite yarns 122 of FIGS. 1-3 for use in forming lightweight protective apparel having enhanced fire or heat resistant resistance and abrasion resistance. These fabrics can be made of woven or knitted construction. For example, fabrics made from the fire and abrasion resistant composite yarn 122 may be woven in a pattern (i.e. a plain pattern, a twill pattern, a basket pattern, a satin pattern, a leno pattern, a crepe pattern, a dobby pattern, a herringbone pattern, a Jacquard pattern, a pique pattern, a warp pile, or in a weave configuration). In other embodiments, such fabrics may be knitted to form articles of clothing, such as a jersey, a rib, a purl, a fleece, a double weft, a tricot, a raschel, a warp knit or a flat knit construction. The resultant fabrics can be used to form various performance and/or protective garments.

[0039] For example, fire and a woven abrasion resistant fire and abrasion resistant woven fabrics formed from a fire and abrasion resistant 20/1Ne spun composite yarn including a blend of a filament FR nylon comprising about 37% by weight of the yarn, spun with about 34% modacrylic and about 28-29% cotton by weight, woven in both the warp and weft directions produced a lightweight fabric having a fabric weight of approximately 261 g/m.sup.2 (approx. 7.7 oz./yd.sup.2), and which included the following properties: [0040] a 7.7 oz./yd.sup.2 ripstop of 4 rips per inch; [0041] approximately 4.76%-5% thermal shrinkage in a length wise direction, and [0042] approximately 4.54% thermal shrinkage in a width wise direction measures/tested according to ASTM F-2894 (Standard Test Method for Evaluation of Materials, Protective Clothing and Equipment for Heat Resistance Using a Hot Air Circulating Oven); [0043] A vertical burn resistance that meets or exceeds Mil Spec. GL-PD-07-12 requirements of 2.0 sec (after glow), 25.0 sec. (after flame), 4.5 inches max char length, and no measured melt/drip; as measured in accordance with ASTM 6413; and [0044] 35,000+ cycles using Martindale Abrasion tester (per ASTM D4966-12) before failing.

[0045] The fabric also is easily dyeable/printable and has a lower cost than similar, conventional fire and abrasion resistant fabrics.

[0046] Although only a few exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the embodiments of the present disclosure. Accordingly, all such modifications are intended to be included within the scope of the embodiments of the present disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures.