STRETCHABLE FABRIC

Abstract

First warp yarns and second warp yarns are each interwoven with weft yarns to produce a one-layer, lightweight, stretchable fabric. The first warp yarns include stretchable yarns that are activatable to achieve a contracted state, and the second warp yarns include non-stretchable yarns. The first warp yarns may include a stretchable core yarn with non-stretchable wrap yarn wrapped around the stretchable core yarn. The first warp yarns may be in an alternating arrangement with the second warp yarns. When the yarns are woven together, the first warp yarns are in an extended state and the second warp yarns are in an unbunched state. The fabric then undergoes a finishing procedure during which the first warp yarns are activated to achieve a contracted state. The second warp yarns thus achieve a bunched state, and the resulting fabric is stretchable in the warp direction.

Description

BACKGROUND

As textile technology advances, consumers seek fabrics and clothing that are functional, comfortable, and affordable. For example, police officers, military personnel, and other individuals may desire clothing that is both fire resistant, to guard against exposure to high heat and flames, and stretchable to allow the wearer to perform his/her required activities with relative ease and comfort. A fabric that satisfies these requirements may thus need to include fabrics that are fire resistant, strong, soft, stretchable, and/or flexible.

Often times, different parts of the same garment are subjected to different forces and must withstand different performance conditions, depending on the proximity to a moving body part. For example, fabric located near a wearer's joint, such as an elbow or a knee, may often experience greater stresses due to the movement of the wearer's joint as the wearer conducts work or recreational activities as compared to other parts of the same garment in other areas, such as the upper arm.

Applicant has discovered then that it would be desirable to provide a fabric that can be used to fashion clothes or parts of clothing that are fire resistant, durable, abrasion resistant, stretchable, comfortable, reliable, and/or attractive. As described in greater detail below, a variety of challenges were identified and overcome through Applicant's efforts to invent and develop such a fabric.

BRIEF SUMMARY OF THE INVENTION

Systems and methods are therefore provided for forming a fabric that incorporates stretchable and non-stretchable yarns into a unitary, one-layer, lightweight, stretchable fabric.

In some embodiments, a fabric is provided that includes a plurality of weft yarns, a plurality of first warp yarns interwoven with the weft yarns, and a plurality of second warp yarns interwoven with the weft yarns. The first warp yarns comprise stretchable yarns and are activatable to achieve a contracted state, and the second warp yarns comprise non-stretchable yarns. The fabric is stretchable in a warp direction upon activation of at least some of the plurality of first warp yarns. At least some of the plurality of second warp yarns may achieve a bunched state upon activation of the first warp yarns. The first warp yarns may comprise Lycra, and the second warp yarns may comprise nylon.

In some cases, at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn. The stretchable core yarn may comprise Lycra, and the non-stretchable wrap yarn may comprise nylon. In some instances, the stretchable core yarn is stretchable to a length between approximately 2 and 7 times the respective yarn's original length under tension and is capable of returning to approximately its original length when no longer under tension. Similarly, the non-stretchable wrap yarn may be incapable of being stretched to a length greater than approximately 2 times the respective yarn's original length under tension or may be plastically deformed when stretched to a length greater than approximately 2 times the respective yarn's original length.

The first warp yarns may float at least two of the plurality of weft yarns. Likewise, the second warp yarns may float at least two of the plurality of weft yarns. Furthermore, the weft yarns may be fire-resistant. At least some of the first warp yarns may comprise stretchable yarns that are stretchable to a length between approximately 2 and 7 times the respective yarn's original length under tension and are capable of returning to approximately its original length when no longer under tension, and at least some of the second warp yarns may comprise non-stretchable yarns that are incapable of being stretched to a length greater than approximately 2 times the respective yarn's original length under tension or are plastically deformed when stretched to a length greater than approximately 2 times the respective yarn's original length.

In other embodiments, a fabric is provided comprising a plurality of weft yarns, a plurality of first warp yarns interwoven with the weft yarns, and a plurality of second warp yarns interwoven with the weft yarns. The first warp yarns are activatable to achieve a contracted state, and at least some of the plurality of second warp yarns achieve a bunched state upon activation of the first warp yarns. The plurality of first warp yarns may be in an alternating arrangement with the plurality of second warp yarns. Furthermore, at least some of the second warp yarns may comprise non-stretchable yarns.

In some cases, at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn. The stretchable core yarn may comprise Lycra, and the non-stretchable wrap yarn may comprise nylon. The non-stretchable wrap yarn may be a first non-stretchable wrap yarn, and at least some of the first warp yarns may further comprise a second non-stretchable wrap yarn. The first non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a first direction and the second non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a second direction.

The fabric may comprise at least one of an anti-microbial and a water-resistant coating. In some instances, the first warp yarns may comprise Lycra and the second warp yarns may comprise nylon. Furthermore, the weft yarns may be fire-resistant.

In still other embodiments, a method of weaving a fabric is provided, in which a plurality of weft yarns, a plurality of first warp yarns in an extended state, and a plurality of second warp yarns are provided. The first warp yarns are interwoven with the weft yarns, and the second warp yarns are interwoven with the weft yarns. The first warp yarns are activated to achieve a contracted state of at least some of the first warp yarns. As a result, the fabric is stretchable in a warp direction upon activation of at least some of the plurality of the first warp yarns. In some cases, the second warp yarns are provided in an unbunched state, and activating the first warp yarns causes at least some of the second warp yarns to move from the unbunched state to a bunched state.

At least some of the first warp yarns may comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn. Also, interweaving the first and second warp yarns with the weft yarns may comprise alternately weaving the first and second warp yarns. Furthermore, the fabric may be chemically treated to impart anti-microbial or water-resistant characteristics to the fabric.

In some cases, interweaving the first warp yarns with the weft yarns comprises floating at least two of the plurality of weft yarns, and interweaving the second warp yarns with the weft yarns comprises floating at least two of the plurality of weft yarns. In addition, providing the plurality of first warp yarns in an extended state may comprise applying tension to the first warp yarns.

In still other embodiments, a fabric is provided that includes a plurality of weft yarns, a plurality of first warp yarns interwoven with the weft yarns, and a plurality of second warp yarns interwoven with the weft yarns. The first warp yarns are in a contracted state and are stretchable between the contracted state and an extended state. Furthermore, the second warp yarns are in a bunched state. Thus, when the fabric is stretched in the warp direction, the plurality of first warp yarns is moved from the contracted state to the extended state, and the plurality of second warp yarns is moved from the bunched state to an unbunched state.

The amount of stretch of the fabric may be limited by a length of the second warp yarns in their respective unbunched states. Also, at least some of the first warp yarns may comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn. The stretchable core yarn may comprise Lycra, and the non-stretchable wrap yarn may comprise nylon. In some cases, the non-stretchable wrap yarn is a first non-stretchable wrap yarn, and at least some of the first warp yarns further comprise a second non-stretchable wrap yarn. Thus, the first non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a first direction, and the second non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a second direction.

In other embodiments, a garment is provided, where at least a portion of the garment comprises a fabric. The fabric, in turn, comprises a plurality of weft yarns, a plurality of first warp yarns interwoven with the weft yarns, and a plurality of second warp yarns interwoven with the weft yarns. The first warp yarns are in a contracted state and are stretchable between the contracted state and an extended state, and the second warp yarns are in a bunched state. When the fabric is stretched in the warp direction, the first warp yarns are moved from the contracted state to the extended state, and the second warp yarns are moved from the bunched state to an unbunched state.

In some cases, at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn. The stretchable core yarn may comprise Lycra, and the non-stretchable wrap yarn may comprise nylon. Furthermore, the non-stretchable wrap yarn may be a first non-stretchable wrap yarn, and at least some of the first warp yarns may further comprise a second non-stretchable wrap yarn. Thus, the first non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a first direction, and the second non-stretchable wrap yarn may be wrapped about the stretchable core yarn in a second direction.

Embodiments of the invention in which first warp yarns and second warp yarns are each interwoven with weft yarns to produce a one-layer, lightweight, stretchable fabric are described in greater detail below.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

FIG. 1A depicts a first surface of a fabric structured in accordance with one exemplary embodiment of the present invention;

FIG. 1B is a schematic representation of the fabric of FIG. 1A;

FIG. 2A depicts a second surface of the fabric of FIG. 1A;

FIG. 2B is a schematic representation of the fabric of FIG. 2A;

FIG. 3A is a schematic representation of a cross-sectional view taken along a first warp yarn of the fabric along line 3A-3A of FIG. 1B;

FIG. 3B is a schematic representation of a cross-sectional view taken along a second warp yarn of the fabric along line 3B-3B of FIG. 1B;

FIG. 4 is a schematic representation of a cross-sectional view taken along a weft yarn of the fabric along line 4-4 of FIG. 1B;

FIG. 5A is a schematic representation of a first warp yarn with a stretchable core and a non-stretchable wrap yarn in a relaxed position structured in accordance with one exemplary embodiment of the present invention;

FIG. 5B is a schematic representation of the first warp yarn of FIG. 5A under tension;

FIG. 6A is a schematic representation of a warpwise cross-section of the fabric of FIG. 1B showing the first warp yarn in a contracted state and the second warp yarn in a bunched state in accordance with one exemplary embodiment of the present invention;

FIG. 6B is a schematic representation of the cross-section of FIG. 6A showing the first warp yarn in an extended state and the second warp yarn in an unbunched state in accordance with one exemplary embodiment of the present invention;

FIG. 7 illustrates clothing made from fabric woven in accordance with one exemplary embodiment of the present invention;

FIG. 8 is a schematic representation of a loom for weaving fabrics in accordance with one exemplary embodiment of the present invention; and

FIG. 9 is a schematic representation of a first warp yarn with a stretchable core and two non-stretchable wrap yarns in accordance with one exemplary embodiment of the present invention.

DETAILED DESCRIPTION

Embodiments of the present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the invention are shown. Indeed, embodiments of the invention may be in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout.

Various embodiments of the present invention are directed to a fabric that is structured to use and combine multiple yarns each selected to provide the fabric with specific qualities, characteristics, and/or functions. For example, fabrics structured in accordance with the present invention may include yarns selected to impart fire resistance, strength, durability, and/or abrasion resistance to the fabric. Other yarns may be selected to impart comfort, breatheability, drapeability, and/or stretchability to the fabric. Still other yarns may be selected to improve the fabric's aesthetic appearance.

In developing fabrics comprised of multiple yarns as discussed above, Applicant discovered that by using a first yarn selected to provide a first quality (e.g., fire resistance), Applicant may inherently be undermining another desired quality (e.g., stretchability or aesthetic appeal). For example, by using modeacrylic fibers for their fire resistance qualities, Applicant may necessarily be introducing a yarn to the fabric that has poor stretchability. As discussed in greater detail below, various embodiments of the present invention are structured to limit such counter-productive effects.

The specification refers for illustration purposes to various textile related terms. For example, the terms “warp” and “weft” are used when describing woven fabrics structured in accordance with various embodiments of the present invention. The term “warp” refers to fibers or yarns that run in the lengthwise or machine direction of the fabric. The term “weft” refers to the fill fibers or yarns that run in a crosswise direction that is transverse to the machine direction of the fabric. Individual weft yarns may be referred to herein as “picks.” A collection of warp yarns having the same weave structure or configuration is referred to herein as a warp system. As illustrated and described below with reference to the figures, warp yarns may be classified as having the same weave structure (and thus part of the same warp system) in situations where the weave structure is shifted with respect to adjacent yarns. The term “yarn” is used throughout the specification to denote a component of the fabric that is interwoven with other components to form the fabric. For example, yarns or threads can include monofilament fibers, multifilament fibers, threads, yarns, staple fibers, composite fibers, and so on.

FIGS. 1A, 1B, 2A, and 2B depict a woven fabric 10 according to an exemplary embodiment, with FIGS. 1A and 1B depicting a first surface 20 and FIGS. 2A and 2B depicting a second surface 25. For purposes of explanation, reference axes are provided on FIGS. 1A, 1B, 2A, and 2B, with the warp yarns extending along the x-axis and the weft yarns extending along the y-axis. The z-axis in FIGS. 1A, 1B, 2A, and 2B extends out of the page. FIGS. 3A and 3B illustrate a warpwise cross-section of the fabric 10 taken along lines 3A-3A and 3B-3B, respectively, of FIG. 1B, or in the x-z plane, and FIG. 4 illustrates a weftwise cross-section of the fabric taken along line 4-4 of FIG. 1B. Thus, in FIGS. 3A and 3B the y-axis extends into the page, and in FIG. 4 the x-axis extends out of the page.

Turning to FIG. 1B, in an exemplary embodiment, the depicted woven portion of fabric 10 includes a plurality weft yarns 30 and two warp systems 40, 45. As described in greater detail below, the first warp yarns 40 may be interwoven with the weft yarns 30, and the second warp yarns 45 may be interwoven with the weft yarns 30 in accordance with embodiments of the present invention to produce a one-layer fabric that is stretchable in a warp direction (i.e., along the x-axis) upon activation of at least some of the plurality of first warp yarns. Thus, Applicant has discovered that in forming a fabric having the structure described below, the first and second warp yarns 40, 45 can be selected and configured with respect to each other to allow the fabric to stretch in the warp direction while the weft yarns 30 may be selected to provide other performance characteristics, such as fire resistance, to the fabric without regard to the stretchability of the weft yarns.

FIGS. 3A and 3B show cross-sections of the depicted fabric portion 10 taken along one of the first warp yarns 40 and one of the second warp yarns 45, respectively. For ease of explanation, 6 weft yarns 30 are shown arranged in a single row. The 6 weft yarns have been sequentially identified for illustration purposes and are referred to herein as “pick a,” “pick b,” “pick c,” “pick a,” “pick b,” and “pick c.” Although the figures depict the diameters of the warp yarns and the weft yarns to be similar, the diameters of the yarns may be the same or different and are not limited to the schematic representation provided in the figures. For example, the first and/or second warp yarns may have a larger diameter than the weft yarns, or vice versa. In addition, although the figures depict a single yarn for each of the two warp systems 40, 45, one or more of the warp systems may include multiple yarns, as discussed below.

In the depicted embodiment, each of the first warp yarns 40 is structured to pass over two weft yarns (e.g., picks c and a) and under one weft yarn (e.g., pick b) in a configuration that may be repeated throughout the fabric, as shown in FIG. 3A. Similarly, in FIG. 3B, each of the second warp yarns 45 is structured to pass over two weft yarns (e.g., picks b and c) and under one weft yarn (e.g., pick a). As a result of this configuration, a cross-section taken along a weft yarn 30 also presents a “two float” structure, as shown in FIG. 4. The “two float” structure of FIGS. 3A, 3B, and 4 could be replaced with a three float structure (i.e., the first and/or second warp yarns pass over three picks before proceeding under one) or other weave structures having greater or fewer numbers of floats depending upon fabric design requirements, as will be understood by one of ordinary skill in the art in light of this disclosure. For example, in other embodiments, warp systems having three or more floats may be used to provide greater flexibility, stretch, and/or drapeability to the fabric. Furthermore, in some embodiments, different warp systems may have a different number of floats. For example, the first warp yarns 40 may be woven to incorporate two floats, whereas the second warp yarns may be woven to include three or more floats.

The repeated weave structure of the two warp systems 40, 45 may be shifted in the warp direction (along the x-axis direction), for example, when cross-sections taken at different weftwise positions (positions along the y-axis) of the fabric are compared, resulting in a tweed pattern of the fabric. The depicted construction, however, is only one example of a weave structure of the fabric. Embodiments may include numerous other basic and complex constructions, as will be understood by one skilled in the art in light of this disclosure.

In some embodiments, the first warp yarns 40 are in an alternating arrangement with the second warp yarns 45. Thus, as shown in FIGS. 1B and 2B, a single first warp yarn 40 may alternate with a single second warp yarn 45 such that each first warp yarn is adjacent two second warp yarns, one on either side (except perhaps at the boundaries of the fabric). In another embodiment, however, the weftwise pattern may include 2 first warp yarns 40 alternating with a single second warp yarn 45, 2 first warp yarns alternating with 2 second warp yarns, 3 first warp yarns alternating with 1 second warp yarn, 1 first warp yarn alternating with 3 second warp yarns, and so on, as dictated by the wearer's performance needs, the desired aesthetic appearance of the fabric, and other design considerations.

Referring again to FIG. 1B, some of the warp yarns may be stretchable, and others of the warp yarns may be non-stretchable, or at least may not be as stretchable as the stretchable yarns (i.e., may exhibit some stretchability, but not as much as the stretchable yarns). In particular, the first warp yarns 40 may comprise stretchable yarns, for which a force applied along the axis of the stretchable yarn results in a temporary lengthening of the yarn (i.e., elastic deformation), with the yarn returning to approximately its original length once the force is removed. For example, a stretchable yarn may be a yarn that can be stretched to approximately 200% to 700% of its original length (i.e., 2 to 7 times its original length) under tension and returns to approximately its original length when no longer under tension. Examples of stretchable yarns include Spandex or elastane fibers, such as Lycra® and Dorlastan® fibers, latex, and polyurethane rubber fibers.

At least some of the second warp yarns 45 may comprise non-stretchable yarns. Non-stretchable yarns are yarns that exhibit little or no stretchability. For example, a non-stretchable yarn may be a yarn that stretches to less than twice its original length under tension (e.g., a yarn that fractures or breaks when stretched to, for example, 1.5 times its original length) or a yarn that, once lengthened under tension, is permanently elongated (i.e., plastically deformed) and does not have the elasticity to return to approximately its original length after the force is removed. In other words, although the yarn may not remain at its extended length once the tensile force is removed, it is not able to fully return to approximately its original (e.g., pre-tension) length.

Nylon 6 and Nylon 6,6, for example, are 100% elastic only when extended to a length that is less than 1.08 times the original yarn's length. Beyond this extension, such yarns undergo plastic deformation and are thus characterized herein as non-stretchable yarns. Similarly, texturized nylon yarns are typically stretchable in the range of approximately 1.06 to 1.34 times the yarn's original length. Other examples of non-stretchable yarns include cotton, wool, rayon, polyamid fibers, modeacrylic fibers, high modulus fibers, Kevlar® fibers, Nomex® fibers, high molecular weight polyethylene, aramids, fiberglass, and carbon fibers. Thus, such yarns are not stretchable relative to the yarns described above that are stretchable yarns, such as Lycra® yarns.

In another aspect of the depicted embodiment, the weft yarns may be fire-resistant. For example, the weft yarns may be modacrylic fibers that exhibit fire-resistant properties, but are non-stretchable. In this way, the fabric may be useful in garments designed for exposure to high heat and/or fire, such as in certain military or fire-fighting applications.

In some embodiments, each first warp yarn 40 may comprise two yarns (e.g., in parallel, twisted, wrapped, etc.) that are interwoven with the weft yarns 30 in the same manner as described above. In particular, in some embodiments, at least some of the first warp yarns 40 comprise a stretchable core yarn 41 and a non-stretchable wrap yarn 42 wrapped around the stretchable core yarn, as illustrated in FIG. 5A. For example, the stretchable core yarn 41 may be Lycra® fiber or a Lycra® fiber blend, whereas the non-stretchable wrap yarn 42 may be nylon. Although in this example a stretchable yarn (i.e., the stretchable core yarn 41) is arranged with a non-stretchable yarn (i.e., the non-stretchable wrap yarn 42), the resulting first warp yarn 40 may be stretchable to approximately 1.05 to 2 times its original length. This is because as the stretchable core yarn 41 lengthens under tension (FIG. 5B), the non-stretchable wrap yarn 42 “straightens out” to allow for the lengthening of the core yarn. In other words, the number of turns of the non-stretchable wrap yarn 42 per unit length of the core yarn 41 decreases as the core yarn is stretched, and the first warp yarn 40 as a whole increases in length as tension is applied. Although the stretchable core yarn 41 may be stretchable alone to 4 times its original length, for example, a first warp yarn 40 comprised of a stretchable core yarn 41 and a non-stretchable wrap yarn 42 may only be stretchable to 1.3 times its original length. This limitation may be adjusted based on the length of the wrap yarn and the density of the wrapping about the core (e.g., the number of turns per unit length). Thus, the greater the density of the wrapping about the core, the lower the stretchability of the resulting first warp yarn 40.

The length of the non-stretchable wrap yarn 42 is thus generally greater than the length of the stretchable core yarn 41, for example to account for the number of turns of the wrap yarn per unit length of the core yarn. In addition, in some cases, multiple non-stretchable wrap yarns 42 are wrapped around the stretchable core yarn 41 in an effort to balance the forces on the core yarn. For example, referring to FIG. 9, a first wrap yarn 42a may be wrapped from left to right about the core yarn 41, and a second wrap yarn 42b may be wrapped from right to left over the first wrap yarn 42a and the core yarn. In this way, the forces exerted on the core yarn 41 by the first wrap yarn 42a are counteracted and/or “balanced” by the second wrap yarn 42b wrapped in the opposite direction, giving the fabric additional stability (e.g., preventing rolling of the fabric).

Turning again to FIG. 1B, the first warp yarns 40 may be interwoven with the weft yarns 30 in an extended state and may be activatable to achieve a contracted state. For example, the first warp yarns 40 may be treated (e.g., chemically treated) such that each first warp yarn has a tendency to remain in the extended state without the application of any, or as much, tensile force. In addition, during the weaving process, the first warp yarns 40 may be held in tension to achieve the extended state. Thus, in some embodiments (e.g., embodiments in which the first warp yarn 40 comprises a stretchable core yarn 41 and a non-stretchable wrap yarn 42), the length of each first warp yarn 40 in the extended state may be approximately 1.1 to 2.5 times its original, or contracted, length, depending on the amount of stretchability to be imparted to the finished fabric for a particular application. The first warp yarns 40 may thus be activatable to change state from the extended state to the contracted state. In other words, in the extended state, even after the tension applied to the first warp yarns 40 during the weaving process is removed, the first warp yarns may have a tendency to remain relatively elongated due to the treatment that the yarn was subjected to prior to weaving. Upon activating the first warp yarns 40, however, the first warp yarns may “shrink” from the extended state to achieve their contracted state.

In one embodiment, activation of the first warp yarns 40 occurs during a finishing procedure that the fabric undergoes after the first warp yarns, the second warp yarns 45, and the weft yarns 30 have been interwoven to form the fabric. The finishing procedure may entail washing the fabric for a short duration at a temperature of approximately 100° C., which may cause the first warp yarns 40 to change from the extended state to the contracted state.

Turning to FIGS. 6A and 6B, in contrast to the extended state of the first warp yarns 40, the second warp yarns 45 may be provided in an unbunched, or relaxed, state for interweaving with the weft yarns 30. As a result of the change of state of the first warp yarns 40 from the extended state to the contracted state, however, the second warp yarns 45 are changed from the unbunched state (FIG. 6B) to a bunched state (FIG. 6A). Thus, the terms “extended” and “unbunched” as used herein refer to a state of the first warp yarns 40 and second warp yarns 45, respectively, in which the respective yarns achieve a relatively longer length. Conversely, the terms “contracted” and “bunched” as used herein refer to a state of the first warp yarns 40 and second warp yarns 45, respectively, in which the respective yarns achieve a relatively shorter length.

More specifically, the second warp yarns 45 may be in a bunched state in the finished fabric, as shown in FIG. 6A, such that each of the second warp yarns is not at its original unbunched length l_u, but rather is held at a reduced or shortened bunched length l_b by the elastic force F₁ of the first warp yarns 40 to remain in the contracted state. In some cases, the bunched length l_b of the second warp yarns 45 in their bunched state is between approximately 20% and 80% of the unbunched length l_u, for example between approximately 70% and 75% of l_u. As a result of this configuration of the second warp yarns 45 with respect to the first warp yarns 40, the finished fabric 10 is stretchable in the warp direction to between approximately 1.1 and 2 times its original dimension in the warp direction, for example between approximately 1.1 and 1.42 times its original warp dimension (i.e., between 10% and 42% stretch).

Thus, the bunched configuration of the second warp yarns 45 within the finished fabric 10 allows the first warp yarns 40 to stretch, thereby allowing the fabric as a whole to be stretchable in the warp direction. In other words, as the first warp yarns 40 are stretched (e.g., when a tensile force F₂ is applied to the fabric, for example, due to the wearer's activity), the second warp yarns 45 are correspondingly moved from the bunched state to the unbunched state. The extent of the fabric's stretchability may be limited by the unbunched length l_u, of the second warp yarns 45. Thus, once the second warp yarns 45 have achieved their unbunched length l_u, the fabric 10 generally cannot be stretched further, even if, individually, the first warp yarns 40 are capable of additional stretch.

As mentioned above, in some embodiments, one or more warp system yarns may include a stretchable yarn to provide flexibility to the fabric. For example, the first warp yarns 40 may be comprised of or include Lycra® yarns, whereas the second warp yarns 45 may include non-stretchable yarns. In still other embodiments of the present invention, the second warp yarns 45 and the weft yarns 30 may be chosen to perform certain functions without regard to the inherent stretchability of the particular yarn. In other words, because of the configuration and arrangement of the first and second warp yarns 40, 45 with respect to each other and the weft yarns 30, the second warp yarns 45 may be selected for their performance characteristics (for example, strength or abrasion resistance), and the weft yarns may be selected for their fire resistance. Thus, the warpwise stretchability of the fabric will be generally based on the stretchability of the first warp yarns 40 and the difference between the bunched length l_b as compared to the unbunched length l_u of the second warp yarns 45.

In one exemplary embodiment, a one-layer stretch, light weight, fire resistant fabric, such as may be suitable for forming outerwear for military applications, may be comprised as follows. In this embodiment, one or more of the warp systems may be composite yarns made of 50% nylon and 50% Lycra® fibers. For example, the first warp yarns 40 may be made of nylon filaments wrapped in two directions over a Lycra® fiber core to form the composite yarn, as discussed above. The second warp yarns 45 may be nylon yarns. The yarns in this example may have various thicknesses, such as 40 denier, 60 denier, or 120 denier Lycra® yarn and 70 denier, 100 denier, or 150 denier nylon yarn, among other thicknesses. The warp systems may each comprise the same nylon-Lycra® fiber blend, or different materials can be used in one or two of the warp systems to provide for different performance characteristics based on the intended use of the fabric. Other yarns that may be used in the warp systems include, for example, cotton, rayon, polyester, nylon, acrylic, and polypropylene, among others. In this exemplary embodiment, the weft yarns may be made of fire resistant yarns, such as monofilament, multifilament in a continuous filament process, or staple fibers, such as in ring spinning or open end spinning systems. Such fire resistant yarns may include, for example, wool, modacrylic, fire resistant rayon, fire resistant polyester, Kevlar® fibers, Nomex® fibers, metallic fibers, fiberglass, and polybenzimidazole (PBI), among others.

In this regard, the yarns of the warp and weft systems may be woven together as described above to form a fabric of twill construction containing 74% modacrylic fibers, 24% nylon, and 2% Lycra® fibers. The finished fabric width may be between 57 inches and 60 inches with a thickness of approximately 0.84 mm, and the fabric may weigh approximately 8.5 oz. per square yard. In addition to having fire resistant characteristics, the resulting fabric of the exemplary embodiment is stretchable in the warp direction, providing enhanced flexibility and comfort to the wearer.

As mentioned above, once the first warp yarns 40, the second warp yarns 45, and the weft yarns 30 are woven together, the fabric may be subjected to a finishing procedure to create the finished fabric 10. In addition to effecting the activation of the first warp yarns 40 from the extended state to the contracted state, and the resulting change of the second warp yarns 45 from the unbunched state to the bunched state, the finishing procedure may also serve to impart other desired characteristics to the fabric, according to the user's requirements. For example, the finishing procedure may include chemically treating the fabric to provide an anti-microbial coating. As another example, the finishing procedure may make the fabric water-resistant or waterproof. In still another example, the finishing procedure may provide the fabric with stain-release capabilities, in addition to numerous other qualities as will be recognized by one skilled in the art in light of this disclosure. Furthermore, the fabric 10 may be dyed or printed upon to provide the fabric with a desired aesthetic appearance. For example, in military applications, the finished fabric may have a camouflage pattern printed upon its surface to aid the wearer in military activities.

In addition to the stretchability of the first warp yarn 40, the length of the first warp yarn in the extended state, and the length of the second warp yarn in the unbunched state, the density of the weave also plays a role in the resulting stretchability of the finished fabric 10. For example, a more densely woven fabric (i.e., less space between the yarns) would provide for less stretchability in the finished fabric, whereas a less densely woven fabric (i.e., more space between the yarns) would provide for greater stretchability in the finished fabric. Thus, based on the preferences of the wearer and the particular application for which the fabric will be used, the materials selected for the first and second warp yarns, the configuration of the first and second warp yarns, and the weave density can be customized and adjusted to produce fabrics with varying degrees of stretchability.

Referring now to FIG. 7, embodiments of the resulting stretchable fabric may be used to fashion various types of clothing in accordance with embodiments of the present invention. For example, the fabric can be used to fashion pants, overcoats, shirts, and undergarments, among many other forms of clothing. In particular, embodiments of the stretchable fabric 10 may be used in certain portions of typical garments that require, for example, additional stretch capabilities with respect to the rest of the garment. For example, embodiments of the stretchable fabric may be used to fortify, enhance, or repair high-stress areas of the garment, such as proximate the elbow 80 the knee 50, pockets 60, and/or the posterior area 65 of pants. Thus, the stretchability provided by the stretchable first warp yarns 40 and the configuration of the first warp yarns with respect to the second warp yarns 45 of the fabric may allow the wearer to move freely while wearing the garment, whereas the selection of an appropriate non-stretchable yarn for the second warp yarns can impart other desired characteristics to the region 80, 50, 60, 65, such as the ability to aesthetically match or resemble the rest of the garment.

For example, in an embodiment in which the first warp yarns 40 are nylon yarns wrapped around a Lycra® yarn core and the second warp yarns 45 are nylon yarns, a “patch” may be made that is both stretchable and has a smooth, unobtrusive look. In other words, rather than be compelled to use solely Lycra® yarns in the warp direction to provide the desired stretchability, which would result in a rough or unfinished-looking patch, by incorporating nylon as a wrap yarn 42 in the first warp yarn 40 and as the second warp yarn 45, the finished fabric portion may have a smooth appearance to match the surface of the remainder of the garment. In addition, the strength of the nylon yarn in turn gives mechanical strength properties to the fabric portion for preventing or reducing cuts and tears through the fabric. In this way, the fabric can be dyed or printed upon in any color to match the look of the clothing. In addition, a yarn such as nylon may also impart additional strength characteristics to the garment in the high-stress areas where it is most needed. Furthermore, in some embodiments, the configuration of the fabric and selection of yarns provides a lightweight material to allow the wearer additional performance flexibility.

As will be apparent to one of skill in the art upon reviewing this disclosure, fabrics configured in accordance with various embodiments of the present invention may be structured to provide more flexible, aesthetically pleasing materials that are customizable for use in a number of applications. In addition to selecting the appropriate material for each of the first and second warp yarns 40, 45 to provide the desired performance characteristics, additional (i.e., third, fourth, etc.) warp yarns may be selected and incorporated into the one-layer stretchable fabric according to the embodiments described above.

The fabric structure 10 described above can be formed using an apparatus such as the loom 100 shown in FIG. 8. The loom 100 includes a first beam 105 holding a supply of warp yarns, such as the first warp yarns 40, and a second beam 110 holding another supply of warp yarns, such as the second warp yarns 45. The first and second beams 105, 110 may be positively driven to advance the warp yarns 40, 45 through the loom 100 to a fabric take-up area 115. As will be apparent to one of skill in the art in view of this disclosure, the warp yarns 40, 45 are fed through heddles 120, each heddle being supported by a frame 125. One or more grippers 130 are used to pull the weft picks 30 through the shed that is created by the movement of the frames 125 and heddles 120. As will be further appreciated by one of ordinary skill in the art, the loom 100 may include hundreds of beams and frames to provide for the weaving of large portions of fabric. Thus, FIG. 5 provides a very simplified illustration for the purposes of explanation, only.

Furthermore, as noted above, in some embodiments, the first warp yarns 40 held on the first beam 105 are in an extended state, such that the first warp yarns are advanced through the loom 100 and interwoven with the second warp yarns 45 and weft yarns 30 while in the extended state. Once the woven fabric has advanced to the take-up area 115, the fabric may then be transported to a finishing station 140 (shown schematically in FIG. 8), where the fabric is subjected to a finishing procedure. As discussed above, the finishing process thus activates the first warp yarns 40, changing the first warp yarns from the extended state to the contracted state and resulting in the second warp yarns 45 changing from the unbunched to the bunched state, thereby providing “built-in” stretchability to the fabric.

Depending on the choice of yarns for weaving the fabric, the fabric may be optimized for particular applications and may exhibit desirable chemical, electrical, thermal, mechanical, and/or physical properties as needed. As such, the fabric can be used to form clothing for various purposes, such as protective clothing for motorcycle operators and construction workers, flame-resistant and/or armored clothing for law enforcement, military personnel, and other types of clothing that may be designed to protect the wearer from one or more particular environmental conditions.

Although embodiments of the fabric discussed above are configured for providing warpwise stretchability, it is understood that the concepts described above can similarly be applied for producing a fabric that is stretchable only in the weft direction or in both the warp and weft directions. Thus, in some embodiments, at least some of the weft yarns may include stretchable yarns and the warp yarns may be selected without regard to stretchability, or both the weft and warp yarns may include stretchable yarns, as will be understood by one skilled in the art in light of this disclosure.

Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A fabric comprising:

a plurality of weft yarns;

a plurality of first warp yarns interwoven with the weft yarns, wherein the first warp yarns comprise stretchable yarns and are activatable to achieve a contracted state; and

a plurality of second warp yarns interwoven with the weft yarns, wherein the second warp yarns comprise non-stretchable yarns;

wherein the fabric is stretchable in a warp direction upon activation of at least some of the plurality of first warp yarns.

2. The fabric of claim 1, wherein at least some of the plurality of second warp yarns achieve a bunched state upon activation of the first warp yarns.

3. The fabric of claim 1, wherein at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn.

4. The fabric of claim 3, wherein the stretchable core yarn comprises Lycra and the non-stretchable wrap yarn comprises nylon.

5. The fabric of claim 3, wherein the stretchable core yarn is stretchable to a length between approximately 2 and 7 times the respective yarn's original length under tension and is capable of returning to approximately the respective yarn's original length when no longer under tension, and wherein the non-stretchable wrap yarn is incapable of being stretched to a length greater than approximately 2 times the respective yarn's original length under tension or is plastically deformed when stretched to a length greater than approximately 2 times the respective yarn's original length.

6. The fabric of claim 1, wherein the first warp yarns comprise Lycra and the second warp yarns comprise nylon.

7. The fabric of claim 1, wherein the first warp yarns float at least two of the plurality of weft yarns.

8. The fabric of claim 1, wherein the second warp yarns float at least two of the plurality of weft yarns.

9. The fabric of claim 1, wherein the weft yarns are fire-resistant.

10. The fabric of claim 1, wherein at least some of the first warp yarns comprise stretchable yarns that are stretchable to a length between approximately 2 and 7 times the respective yarn's original length under tension and are capable of returning to approximately the respective yarn's original length when no longer under tension, and wherein at least some of the second warp yarns comprise non-stretchable yarns that are incapable of being stretched to a length greater than approximately 2 times the respective yarn's original length under tension or are plastically deformed when stretched to a length greater than approximately 2 times the respective yarn's original length.

11. A fabric comprising:

a plurality of weft yarns;

a plurality of first warp yarns interwoven with the weft yarns, wherein the first warp yarns are activatable to achieve a contracted state; and

a plurality of second warp yarns interwoven with the weft yarns;

wherein at least some of the plurality of second warp yarns achieve a bunched state upon activation of the first warp yarns.

12. The fabric of claim 11, wherein the plurality of first warp yarns are in an alternating arrangement with the plurality of second warp yarns.

13. The fabric of claim 11, wherein at least some of the plurality of second warp yarns comprise non-stretchable yarns.

14. The fabric of claim 11, wherein at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn.

15. The fabric of claim 14, wherein the stretchable core yarn comprises Lycra and the non-stretchable wrap yarn comprises nylon.

16. The fabric of claim 14, wherein the non-stretchable wrap yarn is a first non-stretchable wrap yarn, and wherein at least some of the first warp yarns further comprise a second non-stretchable wrap yarn, wherein the first non-stretchable wrap yarn is wrapped about the stretchable core yarn in a first direction and the second non-stretchable wrap yarn is wrapped about the stretchable core yarn in a second direction.

17. The fabric of claim 11, wherein the fabric comprises at least one of an anti-microbial and a water-resistant coating.

18. The fabric of claim 11, wherein the first warp yarns comprise Lycra and the second warp yarns comprise nylon.

19. The fabric of claim 11, wherein the weft yarns are fire-resistant.

20. A method of weaving a fabric comprising:

providing a plurality of weft yarns;

providing a plurality of first warp yarns in an extended state;

providing a plurality of second warp yarns;

interweaving the first warp yarns with the weft yarns;

interweaving the second warp yarns with the weft yarns; and

activating the first warp yarns to achieve a contracted state of at least some of the first warp yarns,

wherein the fabric is stretchable in a warp direction upon activation of at least some of the plurality of the first warp yarns.

21. The method of claim 20, wherein providing the plurality of second warp yarns comprises providing the second warp yarns in an unbunched state, and wherein activating the first warp yarns causes at least some of the second warp yarns to move from the unbunched state to a bunched state.

22. The method of claim 20, wherein at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn.

23. The method of claim 20, wherein interweaving the first and second warp yarns with the weft yarns comprises alternately weaving the first and second warp yarns.

24. The method of claim 20 further comprising chemically treating the fabric to impart anti-microbial or water-resistant characteristics to the fabric.

25. The method of claim 20, wherein interweaving the first warp yarns with the weft yarns comprises floating at least two of the plurality of weft yarns, and wherein interweaving the second warp yarns with the weft yarns comprises floating at least two of the plurality of weft yarns.

26. The method of claim 20, wherein providing a plurality of first warp yarns in an extended state comprises applying tension to the first warp yarns.

27. A fabric comprising:

a plurality of weft yarns;

a plurality of first warp yarns interwoven with the weft yarns, wherein the first warp yarns are in a contracted state, the first warp yarns being stretchable between the contracted state and an extended state; and

a plurality of second warp yarns interwoven with the weft yarns, wherein the second warp yarns are in a bunched state,

wherein, when the fabric is stretched in the warp direction, the plurality of first warp yarns is moved from the contracted state to the extended state and the plurality of second warp yarns is moved from the bunched state to an unbunched state.

28. The fabric of claim 27, wherein the amount of stretch of the fabric is limited by a length of the second warp yarns in their respective unbunched states.

29. The fabric of claim 27, wherein at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn.

30. The fabric of claim 29, wherein the stretchable core yarn comprises Lycra and the non-stretchable wrap yarn comprises nylon.

31. The fabric of claim 29, wherein the non-stretchable wrap yarn is a first non-stretchable wrap yarn, and wherein at least some of the first warp yarns further comprise a second non-stretchable wrap yarn, wherein the first non-stretchable wrap yarn is wrapped about the stretchable core yarn in a first direction and the second non-stretchable wrap yarn is wrapped about the stretchable core yarn in a second direction.

32. A garment, at least a portion of the garment comprising a fabric, wherein the fabric comprises:

a plurality of weft yarns;

a plurality of first warp yarns interwoven with the weft yarns, wherein the first warp yarns are in a contracted state and are stretchable between the contracted state and an extended state; and

a plurality of second warp yarns interwoven with the weft yarns, wherein the second warp yarns are in a bunched state,

wherein, when the fabric is stretched in the warp direction, the first warp yarns are moved from the contracted state to the extended state and the second warp yarns are moved from the bunched state to an unbunched state.

33. The garment of claim 32, wherein at least some of the first warp yarns comprise a stretchable core yarn and a non-stretchable wrap yarn wrapped around the stretchable core yarn.

34. The garment of claim 33, wherein the stretchable core yarn comprises Lycra and the non-stretchable wrap yarn comprises nylon.

35. The garment of claim 33, wherein the non-stretchable wrap yarn is a first non-stretchable wrap yarn, and wherein at least some of the first warp yarns further comprise a second non-stretchable wrap yarn, wherein the first non-stretchable wrap yarn is wrapped about the stretchable core yarn in a first direction and the second non-stretchable wrap yarn is wrapped about the stretchable core yarn in a second direction.