Patent Grant
7797968
Not Applicable.
1. Field of the Invention
This invention relates to circular knitting yarns into fabrics, and specifically to circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece comprising both spun and/or continuous filament hard yarns, and bare elastomeric yarns. In particular, the presently claimed and disclosed invention relates to fabrics that have been circular knitted in a manner in which the draft of the bare elastomeric yarn is controlled and in which a hydro-setting step is utilized to provide a finished fabric having predefined use characteristics without the need for an additional dry heat setting step.
2. Brief Description of the Art
Single knit jersey fabrics are broadly used to make underwear and top-weight garments, such as T-shirts. Compared to woven structures, the knit fabric can more easily deform, or stretch, by compressing or elongating the individual knit stitches (comprised of interconnected loops) that form the knit fabric. This ability to stretch by stitch rearrangement adds to the wearing comfort of garments made from knit fabrics. Even when knit fabrics are constructed of 100% hard yarns, such as cotton, polyester, nylon, acrylics or wool, for example, there is some recovery of the knit stitches to their original dimensions after imposed forces are removed. However, this recovery by knit stitch rearrangement is generally not complete because the hard yarns, which are not elastomeric, do not provide a recovery force sufficient to completely rearrange the knit stitches. As a consequence, single knit fabrics may experience permanent deformations or ‘bagging’ in certain garment areas where more stretching occurs, such as at the elbows of shirt sleeves, for example.
To improve the recovery performance of circular, single knit fabrics, it is now common to co-knit a small amount of an elastomeric fiber, such as a spandex fiber, with the companion hard yarn.
Traditionally, if heat-setting is not used to “set” the spandex after the fabric is knitted and released from the constraints of the circular knitting machine, the stretched spandex in the fabric will retract to compress the fabric stitches so that the fabric is reduced in dimensions compared to what those dimensions would be if the spandex were not present.
Heat setting is not used for all varieties of weft knit elastic fabrics. In some cases a heavy knit will be desired, such as in double knits/ribs and flat sweater knits. In these cases, some stitch compression by the spandex is acceptable. In other cases, the bare spandex fiber is covered with natural or synthetic fibers in a core-spinning or spindle-covering operation, so that the recovery of the spandex and resultant stitch compression is restrained by the covering. In still other cases, bare or covered spandex is plated only on every second or third knit course, thereby limiting the total recovery forces that compress the knit stitches. In seamless knitting, a process wherein tubular knits are shaped for direct use while being knitted on special machines, the fabric is not heat set because dense, stretchy fabric is intended. For circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece made for cutting and sewing, however, wherein bare spandex is plated in every course, heat setting is almost always required.
Heat setting has several disadvantages. Heat setting is an extra cost to finish knit elastic fabrics that contain spandex, versus fabrics that are not elastic (rigid fabrics). Moreover, high spandex heat setting temperatures can adversely affect sensitive companion hard yarns, e.g., yellowing of cotton, thereby requiring more aggressive subsequent finishing operations, such as bleaching. Aggressive bleaching can negatively affect fabric tactile properties, for example, the “hand” of the fabric, and usually requires the manufacturer to include fabric softener to counteract bleaching. Furthermore, certain fibers cannot withstand high temperature heat treatment. Heat-sensitive hard yarns, such as those from polyacryonitrile, wool and acetate, cannot be used in high temperature spandex heat setting steps, because the high heat setting temperatures will adversely affect such heat-sensitive yarns. Finally, other fibers are sensitive to heat due to low fiber melting point. Polypropylene, for example, has a softening point of 155° C., which renders it unsuitable for fabric processing which requires heat setting.
The disadvantages of heat setting have long been recognized, and, as a result, spandex compositions that heat-set at somewhat lower temperatures have been identified (U.S. Pat. Nos. 5,948,875 and 6,472,494, both of which are hereby expressly incorporated herein by reference in their entirety). For example, the spandex defined in U.S. Pat. No. 6,472,494 has a heat set efficiency greater than or equal to 85% at approximately 175-190° C. The heat set efficiency value of 85% is considered a minimum value for effective heat setting. It is measured by laboratory tests comparing the length of stretched spandex before and after heat setting to the before-stretched spandex length. While such lower heat setting spandex compositions provide an improvement, heat setting is still required, and the costs associated with it have not been significantly reduced.
The traditional practice of making and heat setting circular knit fabrics has further disadvantages. The knit fabric emerges from a circular knitting machine in the form of a continuous tube. As the tube is formed in knitting, it is either rolled under tension onto a mandrel, or it is collected as a flat tube under the knitting machine by plaiting, or loose folding. In either case, the fabric establishes two permanent creases where the fabric tube has been folded or flattened. Although the fabric is “opened” by slitting the fabric tube along one of the creases, subsequent use and cutting of the fabric usually must avoid the remaining crease. This reduces the fabric yield (or the amount of knit fabric that can be further processed into garments).
In view of the foregoing disadvantages, methods are needed for making circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece that have bare elastomeric material plated with spun and/or continuous filament hard yarns, and that avoid the costs and disadvantages associated with the prior art dry heat setting methods. Additionally, the invention allows circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece to be formed (stabilized, dyed, and finished) as a tube, which has material usage advantages over the prior art. French terry, and fleece to be formed (stabilized, dyed, and finished) as a tube, which has material usage advantages over the prior art.
The invention provides circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece that include bare elastomeric material plated with spun and/or continuous filament hard yarns, wherein the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece can be manufactured with commercially acceptable properties without a need for in-fabric elastomeric fiber dry heat setting because: (1) the elastomeric fiber draft can be limited during the knitting process; (2) certain desired single knit fabric parameters can be maintained; and (3) the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece may be contacted with a continuous phase aqueous solution under conditions of temperature and pressure for a period of time sufficient to substantially set the bare elastomeric material.
The first aspect of the invention includes a method for making circular knit, single jersey elastic fabrics in which bare elastomeric material, such as a bare spandex yarn, from 15 to 156 dtex, for example from 17 to 78 dtex, may be plated with at least one hard yarn of spun and/or continuous filament yarn, or blends thereof, with yarn count (Nm) from 10 to 165, for example from 44 to 68. The invention also includes a method for making circular knit, elastic fabrics of at least one of French terry and fleece in which bare elastomeric material, such as a bare spandex yarn, from 15 to 156 dtex, for example from 22 to 78 dtex, may be plated with at least two hard yarns of spun and/or continuous filament yarn, or blends thereof, with yarn count (Nm) from 10 to 165, for example from 34 to 68. In the circular knit, elastic fabrics of at least one of French terry and fleece, the at least two hard yarns may be different. In the circular knit, elastic fabrics of at least one of French terry and fleece, the at least two hard yarns may be the same.
The elastomeric material and the hard yarn can be plated to produce a knit fabric such as circular, flat, tricot, double jersey, ribs, fleece, and interlocks. The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece produced by this knitting method can have a cover factor of from 1.05 to 1.9. During the knitting, the draft on the elastomeric material feed can be controlled so that the elastomeric material may be drafted no more than about 7×, typically no more than 5×, for example no more than 3× its original length when knit to form the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece.
The method further includes a stabilization step which includes applying a hot, hydro-setting treatment to the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece and at a temperature and for a period of time sufficient to allow the elastomeric material in the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece to undergo a change and become substantially “set”. For example, the stabilization step may include hydro-setting circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece in a jet dryer to a temperature ranging from about 105° C. to about 145° C. and for a residence time ranging from about 5 minutes to about 90 minutes. The stabilization step re-deniers the spandex to reduce the fabric load and unload power and fabric basis weight. Because of the stabilization step, the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may not have to undergo a dry heat setting step, such as heating the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece on a tenter frame under tension above about 160° C. in air having a relative humidity of less than about 50%.
Next, the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may be dyed, finished and/or dried at temperatures below the heat setting temperature of the spandex without dry heat setting the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece or the spandex within the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece. Finishing may comprise one or more steps, such as cleaning, bleaching, dyeing, drying, napping, brushing, and, compacting, and any combination of such steps. Typically, the finishing and drying are carried out at one or more temperatures below 160° C. Drying or compacting is carried out while the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece is in an overfeed condition in the warp direction.
The resulting circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may have an elastomeric material content of from about 3.5% to about 30% by weight based on the total fabric weight per square meter, typically from about 3.5% to about 27%, for example from about 5% to about 25% by weight based on the total fabric weight per square meter. In addition, circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may have a cover factor of from about 1.05 to about 1.9, for example, from about 1.29 to about 1.4.
The second and third aspects of the invention are the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece made according to the inventive method, and garments constructed from such fabrics. The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece produced by the inventive method can be formed with synthetic filament, spun staple yarn of natural fibers, natural fibers blended with synthetic fibers or yarns, spun staple yarn of cotton, cotton blended with synthetic fibers or yarns, spun staple polypropylene, polyethylene or polyester blended with polypropylene, polyethylene or polyester fibers or yarns, and combinations thereof and can have a basis weight of from about 100 to about 500 g/m2, for example of from about 140 to about 350 g/m2. The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece also can have an elongation of about 45% to about 175%, for example from about 60% to about 175% in the length (warp) direction, and a shrinkage after washing and drying of about 15% or less, typically, 14% or less, for example less than about 7% in both length and width. The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may have been exposed to a temperature no higher than about 160° C. (such as shown by differential scanning calorimetry or molecular weight analysis of the spandex). The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece may be in the form of a tube (as output from a circular knitting process), or in the form of a flat knit. The fabric tube may be slit to provide a flat fabric. The circular knit, elastic fabric of at least one of single jersey, French terry, and fleece typically has a curling value of about 1.0 or less, for example about 0.5 or less face curl. Garments made from the elastic fabrics of at least one of single jersey, French terry, and fleece may include swimwear, underwear, t-shirts, and top or bottom-weight garments, such as for ready-to-wear, athletic, or outdoor wear.
The present invention includes a circular knit, elastic fabric of at least one of single jersey, French terry, and fleece having at least one elastomeric material incorporated therein, wherein the at least one elastomeric material can be drafted no more than about 7×, typically no more than 5×, for example no more than 3× its original length, and the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece can be exposed to a hydro-setting step prior to or during a dyeing procedure.
The present invention further includes a method for producing a circular knit, elastic fabric of at least one of single jersey, French terry, and fleece having at least one elastomeric material incorporated therein, wherein the method involves drafting the at least one elastomeric material no more than about 7× its original length, and wherein the method includes a hydro-setting step and may not include a dry heat setting step. Fabrics of the present invention may have less than about 50% of the bare spandex contact points fused, typically less than about 30%, for example less than about 10% of the bare spandex contact points fused.
The present invention further includes a circular knit, elastic fabric of at least one of single jersey, French terry, and fleece having at least one elastomeric material incorporated therein, wherein the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece can be produced in the form of a tube and can exhibit a wash shrinkage of less than about 15%, typically, 14% or less, for example 7% or less. The knit fabric tube can have no side creases formed therein, and the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece can be used for cutting and sewing such fabric into garments.
The present invention further includes a circular knit, elastic fabric of at least one of single jersey, French terry, and fleece formed of a heat sensitive hard yarn and at least one elastomeric material incorporated therein.
Other features and advantages of the present invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings and appended claims.
Before explaining at least one embodiment of the invention in detail by way of exemplary drawings, experimentation, results, and laboratory procedures, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings, experimentation and/or results. The invention is capable of other embodiments or of being practiced or carried out in various ways. As such, the language used herein is intended to be given the broadest possible scope and meaning; and the embodiments are meant to be exemplary—not exhaustive. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
The term “elastomeric material” or “elastomer” as used herein will be understood to refer to a synthetic material that has the excellent stretchability and recovery of natural rubber such that the material is capable of repeated stretching to at least twice its original length, as well as immediate and forcible recovery to its approximate original length upon release of stress. The “elastomeric material” is generally a manufactured fiber in which the fiber forming substance is a long chain synthetic polymer having segmented polyurethane. Examples of elastomeric materials that may be utilized in accordance with the present invention include, but are not limited to, spandex, elastane, anidex, elastoester, bi-constituent filament rubber, and combinations thereof.
As used herein, “spandex” means a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer comprised of at least 85% of a segmented polyurethane. The polyurethane is prepared from a polyether glycol, a mixture of diisocyanates, and a chain extender and then melt-spun, dry-spun or wet-spun to form the spandex fiber. The spandex preferably is a commercially available elastane product for circular knitting, such as Lycra® types T162B, T162C, T165C, T169B and T562.
The term “denier” as used herein will be understood to be a relative measure of a linear density (or fineness) of a fiber or yarn. Denier is equivalent numerically to the weight in grams per 9,000 meters length of the material. The term “decitex” as used herein will be understood to be equivalent to the weight in grams of a 10,000 meter length of the material.
The term “draft” as used herein refers to the amount of stretch applied to a strand of elastomeric material, such as spandex, resulting in a reduction in linear density of the strand of elastomeric material. The draft of a fiber is directly related to the elongation (stretching) applied to the fiber. For example, 100% elongation corresponds to 2× draft, and 200% elongation corresponds to 3× draft, etc.
The term “hard yarns” as used herein will be understood to refer to knitting yarns which do not contain a high amount of elastic stretch, such as natural and/or synthetic spun staple yarns, natural and/or synthetic continuous filament yarns, and combinations thereof. Examples of materials that may be utilized in the spun staple and/or continuous filament hard yarns in accordance with the present invention include, but are not limited to, cotton, polyester, nylon, polypropylene, polyethylene, acrylics, wool, acetate, polyacryonitrile, and combinations thereof. Natural fibers as used herein will be understood to refer to fibers such as cellulosic (i.e. cotton, bamboo) or protein (i.e. wool, silk, soybean) fibers.
The term “hard yarn count” as used herein will be understood to refer to a measure of the fineness or linear density of a yarn. Hard Yarn Count may be expressed in indirect units (length per unit of weight or mass) or direct units (weight per unit of length). In one embodiment, hard yarn count is represented as “Ne” in the English system of measurement and as “Nm” in the Metric system of measurement.
As used herein, the term “warp direction” refers to the length direction of the fabric, and the term “weft direction” refers to the width direction of the fabric.
The term “Cover Factor” as used herein will be understood to refer to the ratio of fabric surface occupied by yarns to total fabric surface. The Cover Factor is a relative measure of the openness of each knit stitch that characterizes the structural design of a circular knit fabric. This “openness” is related to the percentage of the area that is open versus that which is covered by the yarn in each stitch. The calculation of the Cover Factor is described in further detail herein below.
The term “dry heat setting” as used herein will be understood to refer to a step involving positioning of a fabric on a tenter frame under tension and exposing the fabric to temperatures above about 160° C., and generally in a range of from about 175° C. to about 200° C., in air having a relative humidity of less than about 50%, for a sufficient amount of time to stabilize the spandex at a lower denier. In dry heat setting, the spandex permanently changes at a molecular level so that recovery tension in the stretched spandex is mostly relieved and the spandex becomes stable at a new and lower denier.
The term “hydro-setting” as used herein will be understood to refer to a step in the presently claimed and disclosed invention, in which the knitted fabric is treated with hot water (for example, having a temperature of about 105° C. or higher), at very low tension and for a period of time sufficient to allow the elastomeric material in the fabric to undergo a change and become at least in part stabilized.
The term “fusing” as used herein will be understood to refer to the melting together of bare spandex yarns at contact points in the fabric. Fabrics of the present invention may have less than about 50% of the bare spandex contact points fused, for example, less than about 30%, about 10%, or about 5% of the bare spandex contact points fused.
As used herein, the terms “molecular weight analysis” and “differential scanning calorimetry” refer to methods for determining the highest temperature at which a sample of spandex has been exposed. The term “molecular weight analysis” refers to a method of analyzing the molecular weight of an elastomeric material and correlating that to the thermal history of the elastomeric material. The term “differential scanning calorimetry” refers to a measurement of the amount of energy (heat) absorbed or released by a sample as it is heated, cooled, or held at a constant temperature.
For knit constructions in circular knit machines, the process of co-knitting spandex is called “plating.” With plating, the hard yarn and the bare spandex yarn are knitted in parallel, side-by-side relation, with the spandex yarn always kept on one side of the hard yarn, and hence on one side of the knitted fabric.
By “circular knitting” is meant a form of weft knitting in which the knitting needles are organized into a circular knitting bed. Generally, a cylinder rotates and interacts with a cam to move the needles reciprocally for knitting action. The yarns to be knitted are fed from packages to a carrier plate that directs the yarn strands to the needles. The circular knit fabric emerges from the knitting needles in a tubular form through the center of the cylinder.
The steps for making elastic circular knit fabrics according to one known process 40 are outlined in
In open-width finishing, the knitted tube is then slit open 44 and laid flat. The open fabric is subsequently relaxed 46, either by subjecting it to steam, or by wetting it by dipping and squeezing (padding). The relaxed fabric is then applied to a tenter frame and heated (for heat setting 46) in an oven. The tenter frame holds the fabric on the edges by pins, and stretches it in both the length and width directions in order to return the fabric to desired dimensions and basis weight. This heat setting is accomplished before subsequent wet processing steps and, consequently, heat setting is often referred to as “pre-setting” in the trade. At the oven exit, the flat fabric is released from the stretcher and then tacked 48 (sewed) back into a tubular shape. The fabric then is processed in tubular form through wet processes 50 of cleaning (scouring) and optional bleaching/dyeing, e.g., by soft-flow jet equipment, and then dewatered 52, e.g., by squeeze rolls or in a centrifuge. The fabric is then “de-tacked” 54 by removing the sewing thread and re-opening the fabric into a flat sheet. The flat, still wet, fabric is then dried/heat set 56 in a tenter-frame oven under conditions of fabric overfeed (opposite of stretching) so that the fabric is under no tension in the length (machine) direction while being dried at temperatures below heat-setting temperatures. The fabric is slightly tensioned in the width direction in order to flatten any potential wrinkling. An optional fabric finish, such as a softener, may be applied just prior to the drying/heatsetting operation 56. In some cases, a fabric finish is applied after the fabric is first dried by a belt or tenter-frame oven, so that the finish is taken up uniformly by fibers that are equally dry. This extra step involves re-wetting the dried fabric with a finish, and then drying the fabric again in a tenter-frame oven.
Heat setting of dry fabric in a tenter frame or other drying apparatus “sets” spandex in an elongated form. This is also known as redeniering, wherein a spandex of higher denier is drafted, or stretched, to a lower denier, and then heated to a sufficiently high temperature, for a sufficient time, to stabilize the spandex at the lower denier. Heat setting therefore means that the spandex permanently changes at a molecular level so that recovery tension in the stretched spandex is mostly relieved and the spandex becomes stable at a new and lower denier. Heat setting temperatures for spandex are generally in the range of about 175° C. to about 200° C. For the widely known prior art process 40 shown in
Compression of the stitches in the knitted fabric has three major effects that are directly related to elastic knit fabric properties, and thereby usually renders the fabric inappropriate for subsequent cut and sew operations.
First, stitch compression reduces fabric dimensions and increases fabric basis weight (g/m2) beyond desired ranges for circular knit, elastic fabric of at least one of single jersey, French terry, and fleece for use in garments. As a result, the traditional finishing process for elastic circular knit fabric includes a fabric stretching and heating step, which occurs at sufficiently high temperatures and sufficiently long residence time, so that the spandex yarn in the knit will “set” at desired stretched dimensions. After heat setting, the spandex yarn will either not retract, or will retract only modestly below its heat-set dimension. Thus, the heat-set spandex yarn will not significantly compress the knit stitches from the heat-set dimensions. Stretching and heat setting parameters are chosen to yield the desired fabric basis weight and elongation, within relatively tight limits. For a typical cotton-jersey elastic single knit, the desired elongation is at least 60%, and the basis weight ranges from about 140 to about 500 g/m2.
Second, the more severe the stitch compression, the more the fabric will elongate on a percentage basis, thus far exceeding minimum standards and practical needs. When a plated knit with elastic yarn is compared with a fabric knit without elastic yarn, it is common for the plated elastic knit fabric to be 50% shorter (more compressed) than the fabric without elastic yarn. The plated knit is able to stretch in length 150% or more from this compressed state, and such excessive elongation is generally undesirable in jersey knits for cut and sew applications. This length is in the warp direction of the fabric. Fabrics with high elongation in length (stretch) are more likely to be cut irregularly, and are also more likely to shrink excessively upon washing. Similarly, stitches are compressed by spandex in the width direction, so that fabric width is reduced about 50% as well, far beyond the 15 to 20% as-knit width reduction normally encountered with rigid (non-elastic) fabrics.
Third, the compressed stitches in the finished fabric are at an equilibrium condition between spandex recovery forces and resistance to stitch compression by the companion hard yarn. Washing and drying of the fabric can reduce the hard-yarn resistance, probably in part because of agitation of the fabric. Thus, washing and drying may permit the spandex recovery forces to further compress the knit stitches, which can result in unacceptable levels of fabric shrinkage. Heat-setting the knit fabric serves to relax the spandex and reduce the spandex recovery force. The heat setting operation therefore improves the stability of the fabric, and reduces the amount that the fabric will shrink after repeated washings.
The subject of the presently disclosed and claimed invention is circular knitting and, in particular, the manufacture of circular knit, elastic fabric of at least one of single jersey, French terry, and fleece for subsequent ‘cut and sew’ use. These knit elastic fabrics are formed of an elastomeric material and a hard yarn, wherein the elastomeric material is drafted no more than about 7× and the knit elastic fabric is subjected to a hydro-setting step and is not dry heat set. The resulting fabric may have superior performance relative to known fabrics in terms of achieving fabric basis weight of about 100 g/m2 to about 400 g/m2 with reduced fabric shrinkage and acceptable fabric elongation. Additionally, an improvement in fabric curling is found when hydro-setting is applied to fabrics with a final weight of from about 100 g/m2 to about 400 g/m2.
The presently disclosed and claimed invention also relates to a process for making circular knit, elastic fabric of at least one of single jersey, French terry, and fleece comprising spandex and polypropylene hard yarns without requiring dry heat setting. Since polypropylene fibers cannot be heatset at temperatures required to permanently deform the spandex, the present invention represents a novel method of fabricating spandex-polypropylene knit fabrics. The resulting fabric has superior performance relative to known fabrics in terms of achieving fabric basis weight of about 140 g/m2 to about 400 g/m2 with reduced fabric shrinkage and acceptable fabric elongation. Additionally, an improvement in fabric curling is found when hydro-setting is applied to fabrics with a final weight of 150 to 400 g/m2.
Regarding circular knitting,
For plating knit operations, a spandex yarn 12 and a hard yarn 14 are delivered to the knitting needles 22 by a carrier plate 26. The carrier plate 26 simultaneously directs both yarns to the knitting position. The spandex yarn 12 and hard yarn 14 are introduced to the knitting needles 22 at the same or at a similar rate to form a single jersey knit stitch 10 like that shown in
While the Figures may be described herein in conjunction with the use of spandex yarn, it is to be understood that the use of spandex yarn in the following description is for exemplary purposes only, and thus the present invention is not limited to the use of spandex. Rather, any elastomeric material may be substituted for spandex in the present invention and fall within the scope of the present invention. While the use of another elastomeric material may require parameters that fall outside the ranges described herein, it is to be understood that a person of ordinary skill in the art could easily ascertain the required parameters for the substitute elastomeric material given the teachings and disclosure of the present specification, and therefore such parameters fall well within the scope and teachings of the presently claimed and disclosed invention.
The hard yarn 14 is delivered from a wound yarn package 28 to an accumulator 30 that meters the yarn to the carrier plate 26 and knitting needles 22. The hard yarn 14 passes over a feed roll 32 and through a guide hole 34 in the carrier plate 26. Optionally, more than one hard yarn may be delivered to the knitting needles via different guide holes in the carrier plate 26. For French terry fabric construction of the claimed invention, two hard yarns are knitted with one elastomeric yarn. One hard yarn is plated with the elastomeric yarn as in
The spandex 12 is delivered from a surface driven package 36 and past a broken end detector 39 and change of direction roll(s) 37 to a guide slot 38 within the carrier plate 26. The feed tension of the spandex 12 is measured between the detector 39 and drive roll 37, or alternatively between the surface driven package 36 and roll 37 if the broken end detector is not used. The guide hole 34 and guide slot 38 are separated from one another in the carrier plate 26 so as to present the hard yarn 14 and spandex 12 to the knitting needles 22 in side by side, generally parallel relation (plated).
The spandex stretches (drafts) when it is delivered from the supply package to the carrier plate and in turn to the knit stitch due to the difference between the stitch use rate and the feed rate from the spandex supply package. The ratio of the hard yarn supply rate (meters/min) to the spandex supply rate is normally from about 2.5 to about 4 times greater, and is known as the machine draft. This corresponds to spandex elongation of from about 150% to about 300%, or more. The feed tension in the spandex yarn is directly related to the draft (elongation) of the spandex yarn. This feed tension is typically maintained at values consistent with high machine drafts for the spandex.
The present invention has identified that improved results are obtained over the prior art when the total spandex draft, as measured in the fabric, is kept to about 7× or less, typically 3× or less, for example 2.5× or less. This draft value is the total draft of the spandex, which includes any drafting or drawing of the spandex that is included in the supply package of as-spun yarn. The value of residual draft from spinning is termed package relaxation, “PR”, and it typically ranges from about 0.05 to about 0.15 for the spandex used in circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece. The total draft of the spandex in the fabric is therefore MD*(1+PR), where “MD” is the knitting machine draft. The knitting machine draft is the ratio of hard yarn feed rate to spandex feed rate, both from their respective supply packages.
Because of its stress-strain properties, spandex yarn drafts (draws) more as the tension applied to the spandex increases; conversely, the more that the spandex is drafted, the higher the tension in the yarn. A typical spandex yarn path, in a circular knitting machine, is schematically shown in
The spandex feed tension is measured between the broken end detector 39 and the roll 37 shown in
The presently disclosed and claimed invention does not anticipate all the ways that spandex friction can be minimized between the supply package and the knit stitch. The method requires, however, that friction be minimized in order to keep the spandex feed tensions sufficiently high for reliable spandex feeding while at the same time maintaining the spandex draft to about 7× or less, typically, 3× or less, for example, about 2.5× or less.
After knitting a circular knit, elastic fabric of at least one of single jersey, French terry, and fleece of plated spandex with hard yarn per the method of the presently disclosed and claimed invention, such fabric is finished in any of the alternate processes illustrated diagrammatically in
A second aspect of the present invention is a hot water setting treatment 74 (or 94), which can be carried out immediately before or after the scouring and bleaching step 64 (or 84) (respectively,
Drying operations 70 can be carried out on circular knit, elastic, single jersey fabric in the form of an open width web (top two rows of diagram, paths 65a and 65c), or as a tube (bottom two rows of diagram, paths 65b and 65d). For either of these paths, wet finishing process steps 64 (such as scouring, bleaching and/or dyeing) are carried out on the circular knit, elastic, single jersey fabric while it is in the tubular form. One form of dyeing, called soft-flow jet dyeing, usually imparts tension and some length deformation in the circular knit, elastic, single jersey fabric. Care should be taken to minimize any additional tension applied during fabric processing and transport from wet finishing to the dryer, and also enable the circular knit, elastic, single jersey fabric to relax and recover from such wet-finishing and transport tensions during drying.
Following wet finishing process steps 64, the circular knit, elastic, single jersey fabric is dewatered 66, such as by squeezing or centrifuging. In process paths 65a and 65c, the tubular fabric is then slit open 68 before it is delivered to a finish/dry step 70 for optional finish application (e.g., softener by padding) and subsequent drying in a tenter-frame oven under conditions of fabric length overfeed. In process paths 65b and 65d, the tubular fabric is not slit open, but is sent as a tube to the finish/dry step 70. Finish, such as softener, can be optionally applied by padding. The tubular fabric is sent through a drying oven, e.g., laid on a belt, and then to a compactor to separately provide fabric overfeed. A compactor commonly uses rolls to transport the fabric, usually in a steam atmosphere. The first roll(s) is driven at a faster speed of rotation than the second roll(s) so that the fabric has an overfeed. Generally, the steam does not “re-wet” the fabric so that no additional drying is required after compacting.
The drying step 70 (paths 65a and 65c) or the compacting step 72 (paths 65b and 65d) is operated with controlled, high fabric overfeed in the length (machine) direction so that the fabric stitches are free to move and rearrange without tension. A flat, non-wrinkled or non-buckled fabric emerges after drying. These techniques are familiar to those skilled in the art. For open width fabrics, a tenter-frame is used to provide fabric overfeed during drying. For tubular fabrics, forced overfeed is typically provided in a compactor 72, after belt drying. In either open-width or tubular fabric processing, the fabric drying temperature and residence time are set below the values required to heat set the spandex.
French terry and fleece fabrics are knit, wet finished, and hydro-set similarly to single jersey fabrics,
The drying step 90 (or 92) or the compacting step 106 (or finishing step 102) is operated with controlled, high fabric overfeed in the length (machine) direction so that the fabric stitches are free to move and rearrange without tension. A flat, non-wrinkled or non-buckled fabric emerges after drying. These techniques are familiar to those skilled in the art. For open width fabrics, a tenter-frame is used to provide fabric overfeed during drying. For tubular fabrics, forced overfeed is typically provided in a compactor 106, after turning or napping. In either open-width or tubular fabric processing, the fabric drying temperature and residence time are set below the values required to heat set the spandex.
The structural design of a circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece can be characterized in part by the “openness” of each knit stitch. This “openness” is related to the percentage of the area that is open versus that which is covered by the yarn in each stitch (see, e.g.,
Cf=√(tex)÷L
where tex is the grams weight of 1000 meters of the hard yarn, and L is the stitch length in millimeters.
Cf=√(1000/Nm)÷L.
The presently disclosed and claimed invention describes, in one embodiment, the production of commercially useful circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece plated from bare elastomeric material, such as bare spandex, and a hard yarn that are produced without a dry heat setting step, by maintaining the elastomeric material draft at about 7× or less, typically, 3× or less, for example 2.5× or less, and by designing and manufacturing the knit fabric within the following guidelines:
While not wishing to be bound by any one theory, it is believed that the hard yarn in the knit structure resists the spandex force that acts to compress the knit stitch. The effectiveness of this resistance is related to the knit structure, as defined by the Cover Factor. For a given hard yarn count, Ne, the Cover Factor is inversely proportional to the stitch length, L. This length is adjustable on the knitting machine, and is therefore a key variable for control.
Because the elastomeric material is not heat set in the process of the invention, the elastomeric material draft should be the same in circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece, the finished fabric, or at fabric-processing steps in-between, within the limits of measurement error.
For circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece, the appropriate gauge of knitting machine is selected according to prior art relationships between hard yarn count and knitting machine gauge. Choice of gauge can be used to optimize circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece basis weight, for example.
In the circular knit, elastic fabrics of at least one of French terry and fleece, the at least two hard yarns may be different. In the circular knit, elastic fabrics of at least one of French terry and fleece, the at least two hard yarns may be the same.
The benefits of the presently disclosed and claimed invention are evident when the prior art process shown diagrammatically in
The use of a softener is optional, but commonly a softener will be applied to the circular knit, elastic fabric of at least one of single jersey, French terry, and fleece to further improve fabric hand, and to increase mobility of the knit stitches during drying. Softeners such as SURESOFT SN (Surry Chemical) or SANDOPERM SEI® (Clairant) are typical. The circular knit, elastic fabric of at least one of single jersey, French terry, and fleece may be passed through a trough containing a liquid softener composition, and then through the nip between a pair of pressure rollers (padding rollers) to squeeze excess liquid from such fabric.
Another unexpected advantage of the present invention is that the circular knit, elastic, single jersey fabrics knitted by the method of the invention and collected by folding (plaiting), do not crease to the same extent as prior art circular knit single jersey fabrics. Fewer or less visible fold creases in the finished fabric result in an increased yield for cutting and sewing the fabric into garments. Also unexpectedly, the circular knit, elastic, single jersey fabrics of the invention have significantly reduced “skew”. The decrease in skew is accomplished through either open-width or tubular finishing processes. If a fabric has increased skew or spirality, the fabric is diagonally deformed and knitted courses are “on the bias”. Garments made with skewed fabric will twist on the body and are unacceptable for use.
The following examples demonstrate the presently disclosed and claimed invention and its benefits. The invention is capable of other and different embodiments, and its several details are capable of modifications in various apparent respects, without departing from the scope and spirit of the presently disclosed and claimed invention. Accordingly, the examples are to be regarded as illustrative in nature and not as restrictive.
Fabric Knitting and Finishing
Circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece with bare spandex plated with hard yarn for the examples were knit on either: (1) Pai Lung Circular Knitting Machine Model PL-FS3B/T, with 16 inch cylinder diameter, 28 gauge cylinder (needles per circumferential inch), and 48 yarn feed positions; (2) Pai Lung Circular Knitting Machine Model PL-XS3B/C, with 26 inch cylinder diameter, 24 gauge cylinder, and 78 yarn feed positions; or (3) Monarch Circular Knitting Machine Model VXC-3S, with 30 inch cylinder diameter, 20 gauge cylinder, and 90 yarn feed positions. The 28 and 20-gauge machines were operated at 24 revolutions per minute (rpm), and the 24-gauge machine at 26 rpm.
The broken end detector in each spandex feed path (see
The spandex feed tension was measured between the spandex supply package 36 and the roller guide 37 (
Knitted fabric Examples except 1, 4, 7, 10, 13, 16, 19, 22, 25, 27, 29, 31, and 33-40 were not hydro-set and were finished either per the open-width process 63a or as a tube per the process 63b of
Fabrics were scoured and bleached in a 300-liter solution at 100° C. for 30 minutes. All such wet, jet finishing, including dyeing, was done in a Tong Geng machine (Taiwan) Model TGRU-HAF-30. The water solution contained Stabilizer SIFA (300 g) (silicate free alkaline), NaOH (45%, 1200 g), H2O2(35%, 1800 g), IMEROL ST (Clariant, 600 g) for cleaning, ANTIMUSSOL HT2S (Clariant, 150 g) for antifoaming, and IMACOL S (Clariant, 150 g) for anticreasing. After 30 minutes, the solution and fabric were cooled to 75° C. and then the solution was drained. The fabric was subsequently neutralized in a 300 liter solution of water and HAC (150 g) (hydrogen+dona, acetic acid) at 60° C. for 10 minutes. After scouring, new fresh water was added to the jet for the hydro-set step, 74, in
The fabrics were dyed in a 300-liter solution of water at 60° C. for 60 minutes, using reactive dyestuffs and other constituents. The dye solution contained R-3BF (Clariant, 215 g), Y-3RF (Clariant, 129 g), Na2SO4 (18,000 g), and Na2CO3 (3000 g). After 10 minutes, the dyebath was drained and refilled to neutralize with HAC (150 g) for 10 minutes at 60° C. After neutralization, the bath was again drained and refilled with clean water for a 10-minute rinse. Subsequent to neutralization, the 300-liter vessel was again filled with water, and 150 g of SANDOPUR RSK (Clariant, soap) was added. The solution was, heated to 98° C., and the fabrics were washed/soaped for 10 minutes. After draining and another 10 minute clean-water rinse, the fabrics were unloaded from the vessel.
The wet fabrics were then de-watered by centrifuge, for 8 minutes. For the final step, a lubricant (softener) was padded onto the fabrics in a 77-liter water solution with SANDOPERM SEI liquid (Clariant, 1155g). The fabrics were then dried in a tenter oven at 145° C. for about 30 seconds, at 50% overfeed. The above procedure and additives will be familiar to those experienced in the art of textile manufacturing, and circular knitting of single jersey, French terry, or fleece knit fabrics.
Examples 33-40 were bleached and hydro-set in a jet dye machine (Scholl sample jet rd, Scholl-Then, Safenwil, Switzerland) at 95° C. for 20 minutes. The concentration of ingredients in the bleaching solution, based on fabric weight, were as follows: 8% owf hydrogen peroxide, 1% owf Stabilon EZY® (CIBA Specialty Chemicals, High Point, N.C.), and Acetic Acid to neutralize. The liquor ratio was 1:8. The bleaching bath temperature was raised from 49° C. to 95° C. at the rate of 4° C. per minute. The process was operated at 95° C. for 20 minutes, followed by cool down to 63° C. at the cooldown rate of 7° C. per minute. The bleaching bath was then drained and the machine recharged with 49° C. water heated to 77° C., run for 8 minutes, and drained. The bath was charged once again with 49° C. water, neutralized with acetic acid at 77° C. for 8 minutes, and drained. The bath was charged once again with 49° C. water, heated to 120° C. at a rate of 5° per minute and hydro-set for 20 minutes (examples 33, 35, 37, and 39). Examples 34, 36, 38, and 40 were hydro-set at a temperature of 130° C. for 20 minutes. The temperature was cooled at a rate of 7° per minute to 38° C. and drained. The wet fabrics were then de-watered by squeeze rollers, as per normal practice. For Examples 37-40, the fabrics were relax dried at 143° C. with maximum overfeed using a belt relax dryer (Tubetex, Tubular Textile Group, Lexington; N.C.). The fabrics were turned inside out and compacted with steam and 4% overfeed at 149° C. (Tubetex, Tubular Textile Group, Lexington, N.C.). For Examples 33-36, the fabrics were padded with a nap assist (American Textiles Specialties, Spartanburg, S.C.) were relax dried at 143° C. with maximum overfeed using a belt relax dryer (Tubetex, Tubular Textile Group, Lexington, N.C.). The fabrics were napped using a Gessner Lynx double action-tandem napper (The Gessner Company, Chariton, Mass.) for a total of four times on one side. For the final step, The fabrics were compacted with steam at 4% overfeed at 149° C. (Tubetex, Tubular Textile Group, Lexington, N.C.).
Analytical Methods
Spandex Draft—The following procedure, conducted in an environment at 20° C. and 65% relative humidity, is used to measure the spandex drafts in the Examples.
If the fabric has been heat set, as in the prior art, it is usually not possible to measure the in-fabric spandex draft. This is because the high temperatures needed for spandex heat setting will soften the spandex yarn surface and the bare spandex will tack to itself at stitch crossover points 16 in the fabric (
Fabric Weight—Knit Fabric samples are die-punched with a 10 cm diameter die. Each cut-out knit fabric sample is weighed in grams. The “fabric weight” is then calculated as grams/square meters.
Spandex Fiber Content—Knit fabrics are de-knit manually. The spandex is separated from the companion hard yarn and weighed with a precision laboratory balance or torsion balance. The spandex content is expressed as the percentage of spandex weight to fabric weight.
Fabric Elongation—The elongation is measured in the warp direction only. Three fabric specimens are used to ensure consistency of results. Fabric specimens of known length are mounted onto a static extension tester, and weights representing loads of 4 Newtons per centimeter of length are attached to the specimens. The specimens are exercised by hand for three cycles and then allowed to hang free. The extended lengths of the weighted specimens are then recorded, and the fabric elongation is calculated.
Shrinkage—Two specimens, each of 60×60 centimeters, are taken from the knit fabric. Three size marks are drawn near each edge of the fabric square, and the distances between the marks are noted. The specimens are then sequentially machine washed 3 times in a 12-minute washing machine cycle at 40° C. water temperature and air dried on a table in a laboratory environment. The distances between the size marks are then remeasured to calculate the amount of shrinkage.
Face Curl—A 4-inch×4-inch (10.16 cm×10.16 cm) square specimen is cut from the knit fabric. A dot is placed in the center of the square, and an ‘X’ is drawn with the dot as the center of the ‘X’. The legs of the ‘X’ are 2 (5.08 cm) inches long and in line with the outside corners of the square. The X is carefully cut with a knife, and then the fabric face curls of two of the internal points created by the cut are measured immediately and again in two minutes, and averaged. If the fabric points curl completely in a 360° circle, the curl is rated as 1.0; if it curls only 180°, the curl is rated ½; and so on. Curl values of ¾ or less are acceptable.
Molecular weight analysis—The molecular weight of a spandex fiber can be determined via the following method. An Agilent Technologies 1090 LC (liquid chromatograph, Agilent Technologies, Palo Alto, Calif.), equipped with a UV detector fitted with a 280 nanometer filter in a filter photometric detector and 2 Phenogel™ columns (300 mm×7.8 mm packed with 5 micron column packing of styrene and divinyl benzene in a linear/mixed bed (Phenomex®, Torrance, Calif.), was used to analyze the molecular weight of spandex polymers. Samples were run in mobile phase at a flow rate of 1 ml/min and at a column temperature of 60° C. The sample for analysis is prepared using 2.0-3.0 mg of polymer per ml of solvent. A 50 μl sample of polymer solution was injected into the LC for analysis. The resulting chromatographic data was analyzed using Viscotek 250 GPC software (Viscotek, Houston, Tex.).
The LC was calibrated using a Hamielec Broad standard calibration method and a broad standard was fully characterized for weight average molecular weight (104,000 daltons) and number average molecular weight (33,000 daltons) before use as a standard.
Differential Scanning Calorimetr—This procedure induced four temperatures into the same specimen of spandex without removing the sample from the differential scanning calorimeter (DSC). The DSC instrument was a Perkin Elmer Differential Scanning Calorimeter Model Pyris 1, commercially available from Perkin Elmer (Wellesley, Mass.). The instrument was programmed to start at 50° C. and heat to 140, 160, 180 and 200° C. with a one minute hold at each temperature. The sample was cooled to the starting temperature of 50° C. after each endotherm is scanned, then held at 50° C. for five minutes prior to scanning the next higher temperature.
The specimen was then scanned from 50° C. to 240° C. to locate the endotherms that are induced in the prior test. Each endotherm was found ±3° C. The variance in the endotherms found versus the temperature induced was within the tolerance of the DSC instrument.
Table 1 below sets forth the knitting conditions for the example knit fabrics. Lycra® types T162C, T169B, or T562B were used for the spandex feeds. Lycra® deniers were 55, 40 and 20, or 61 dtex, 44 dtex and 22 dtex, respectively. For examples 29-32, the # of filaments was 72, the Denier per filament was 1.39, and the drying temperature was 130° C. The stitch length, L, was a machine setting. Machine gauge was 28 needles per inch. Table 2 below summarizes key results of the tests for finished fabrics. Values of curl were acceptable for all test conditions, and will not be further discussed below. Spandex feed tensions are listed in grams. 1.00 gram equals 0.98 centiNewtons (cN).
The 20-denier spandex feed tension was 1.5 grams (1.47 cN), which is in the range of 4 to 6 cN. The hard yarn in this example was ring-spun cotton (32 Ne, 165 denier). The fabric was dyed and finished according to the process 63a schematically shown in
The knit fabric of Example 1 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 1,
The knit fabric of Example 1 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 2. The finished fabric in Example 3 had a basis weight of 194 g/m2, which is 11% lower than Example 1.
The knit fabric of Example 1 was dyed and finished according to the process schematically shown in
The knit fabric of Example 1 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 4,
The knit fabric of Example 1 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 5. The finished fabric in Example 6 had a basis weight of 206 g/m2, which is 10% lower than Example 4 and acceptable for a tubular T-shirt garment.
Process parameters were the same as in Example 1, except that a different spandex yarn, Lycra® Type 562B (‘easy-set’) was used for the spandex feed. The results were comparable to the fabric in Example 1.
The knit fabric of Example 7 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 1,
The knit fabric of Example 7 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 1. The knit fabric was processed according to
The knit fabric of Example 7 was dyed and finished according to the process schematically shown in
The knit fabric of Example 7 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 4,
The knit fabric of Example 7 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 11. The finished fabric in Example 12 had a basis weight of 173 g/m2, which is 23% lower than Example 7 and acceptable for a tubular T-shirt garment.
The 20-denier spandex feed tension was 1.70 grams (1.67 cN), which is in the range of 4 to 6 cN. The hard yarn in this example was textured nylon (140 denier/48 filaments). The fabric was dyed and finished according to
The knit fabric of Example 13 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 13,
The knit fabric of Example 13 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 14. The finished fabric in Example 15 had warp elongation that was reduced significantly (>25%) versus the finished fabric in Example 13.
The knit fabric of Example 13 was dyed and finished according to method schematically shown in
The knit fabric of Example 13 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 16,
The knit fabric of Example 13 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 17. The finished fabric in Example 18 had a warp elongation of 69%, which was 28% lower than Example 16 and acceptable for a tubular T-shirt garment. Fabric basis weight, shrinkage, and face curl also were essentially the same as Example 16.
Process parameters were the same as in Example 13, except that a different spandex yarn, Lycra® Type 562B (‘easy-set’) was used for the spandex feed. The results were comparable to those of Example 13.
The knit fabric of Example 19 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 19,
The knit fabric of Example 19 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 20. The knit fabric was processed according to
The knit fabric of Example 19 was dyed and finished according to the process schematically shown in
The knit fabric of Example 19 was treated with hot water (230° F. or 110° C.) for 5 minutes in a jet dyer and dyed and finished similarly to Example 22,
The knit fabric of Example 19 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 23. The finished fabric in Example 24 had a basis weight of 220 g/m2, which is 15% lower than the fabric of Example 22.
The 20-denier spandex draft was 3.0×. The hard yarn in this example was ring-spun cotton (32 Ne, 165 denier). The fabric was dyed and finished according to the process schematically shown in
The knit fabric of Example 25 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 25,
The 40-denier spandex draft was 2.0×. The hard yarn in this example was ring-spun cotton (32 Ne, 165 denier). The fabric was dyed and finished according to the process schematically shown in
The knit fabric of Example 27 was treated with hot water (266° F. or 130° C.) for 15 minutes in a jet dyer and dyed and finished similarly to Example 27,
The hard yarn in this example was textured polypropylene (100 denier, 110 decitex, 1.39 denier/filament). The spandex was Lycra® T162C (55 denier, 61 decitex) drafted at 2.5×. The fabric was dyed and finished according to path 63a,
The knit fabric of Example 29 was treated with hot water (266° F. or 130° C.) for 15 minutes by hydro-setting in a jet dyer 74 and dried, path 65a,
The hard yarn in this example was textured polypropylene (100 denier, 110 decitex, 1.39 denier/filament). The spandex was Lycra® T162C (70 denier, 78 decitex) drafted at 2.0×. The fabric was dyed and finished according to path 63a,
The knit fabric of Example 31 was treated with hot water (266° F. or 130° C.) for 15 minutes by hydro-setting in a jet dyer 74 and dried as in path 65c,
A two end French terry fabric was knit in this example using 100% cotton 30/1 Ne yarn for the jersey feeds and 100% cotton 20/1 Ne yarns for the loops. Jersey feeds were plated with 33 dtex T562B Lycra® at a draft of 1.9×. Fabrics were wet processed (including a hydroheat set at 120° C. for 20 minutes) and napped to give a single-sided fleece finished fabric according to path 85b of
The fabric of Example 33 was wet processed (including a hydroheat set at 130° C. for 20 minutes) and napped to give a single-sided fleece finished fabric according to path 85b of
A two end French terry fabric was knit in this example using 100% cotton 30/1 Ne yarn for the jersey feeds and 100% cotton 20/1 Ne yarns for the loops. Jersey feeds were plated with 22 dtex T562B Lycra® at a draft of 1.9×. Fabrics were wet processed including a hydroheat set at 120° C. for 20 minutes) and napped to give a single-sided fleece finished fabric according to path 85b of
The fabric of Example 35 was wet processed (including a hydroheat set at 130° C. for 20 minutes) and napped to give a single-sided fleece finished fabric according to path 85b of
A two end French terry fabric was knit in this example using 100% cotton 30/1 Ne yarn for the jersey feeds and 100% cotton 20/1 Ne yarns for the loops. Jersey feeds were plated with 33 dtex T562B Lycra® at a draft of 1.9×. Fabrics were wet processed to give a French terry finished fabric according to path 85b of
The fabric of Example 37 was wet processed to give French terry finished fabric according to path 85b of
A two end French terry fabric was knit in this example using 100% cotton 30/1 Ne yarn for the jersey feeds and 100% cotton 20/1 Ne yarns for the loops. Jersey feeds were plated with 22 dtex T562B Lycra® at a draft of 1.9×. Fabrics were wet processed to give a French terry finished fabric according to path 85b of
The fabric of Example 39 was wet to give a French terry finished fabric according to path 85b of
Thus it should be apparent that there has been provided in accordance with the present invention a useful circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece having a bare elastomeric material plated with spun and/or continuous filament hard yarns, as well as methods of producing same that do not require a dry heat setting step, that fully satisfies the objectives and advantages set forth above. Although the invention has been described in conjunction with specific embodiments thereof; it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.
This application is a continuation-in-part of International Application PCT/US2004/017364, designated in the United States and filed Jun. 1, 2004; which PCT application claims benefit under 35 U.S.C. §365(c) of U.S. application Ser. No. 10/454,746, filed Jun. 2, 2003, now U.S. Pat. No. 6,776,014. This application also claims benefit under 35 U.S.C. 119(e) of provisional applications U.S. Ser. No. 60/668,360 (LP-5755), filed Apr. 4, 2005; U.S. Ser. No. 60/613,429 (LP-5680), filed Sep. 27, 2004; and U.S. Ser. No. 60/637,815 (LP-5680), filed Dec. 21, 2004. The entire contents of each of the above-referenced applications are hereby expressly incorporated herein by reference.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3392552 | Muller et al. | Jul 1968 | A |
| 4875241 | Browder et al. | Oct 1989 | A |
| 5198288 | Grunfeld | Mar 1993 | A |
| 5584196 | Taylor et al. | Dec 1996 | A |
| 5687587 | Michel | Nov 1997 | A |
| 5815868 | Lee | Oct 1998 | A |
| 5931023 | Brach et al. | Aug 1999 | A |
| 5948875 | Liu et al. | Sep 1999 | A |
| 6129876 | Qin et al. | Oct 2000 | A |
| 6263707 | Miller et al. | Jul 2001 | B1 |
| 6263797 | Brice | Jul 2001 | B1 |
| 6458166 | Fleissner | Oct 2002 | B1 |
| 6472494 | Houser et al. | Oct 2002 | B2 |
| 6776014 | Laycock et al. | Aug 2004 | B1 |
| 6846866 | Houser et al. | Jan 2005 | B2 |
| 7040124 | Miller et al. | May 2006 | B1 |
| 7117695 | Laycock et al. | Oct 2006 | B2 |
| Number | Date | Country |
|---|---|---|
| 0119536 | Sep 1986 | EP |
| 0369822 | May 1990 | EP |
| 1375717 | Jan 2004 | EP |
| 1437432 | Jul 2004 | EP |
| Number | Date | Country | |
|---|---|---|---|
| 20060021387 A1 | Feb 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2004/017364 | Jun 2004 | US |
| Child | 11202735 | US |
