KR20240046297A - Stretch circular knit fabrics containing elastomeric fiber and polyester bi-component filament, garments made therefrom and a method of making same - Google Patents

Abstract

Stretch circular knit fabrics (40, 82, 94) containing two sets of different elastic fibers (12, 18) and optionally hard yarns (14) and methods for their production are provided.

Description

STRETCH CIRCULAR KNIT FABRICS CONTAINING ELASTOMERIC FIBER AND POLYESTER BI-COMPONENT FILAMENT, GARMENTS MADE THEREFROM AND A METHOD OF MAKING SAME}

The present invention relates to the production of a stretch circular knit fabric containing two sets of different elastic fibers with improved anti-see-through, high retention and recovery properties. Elastic circular knit fabrics are produced from elastomeric elastic fibers and polyester bi-component filaments and optionally hard yarns.

Elastomeric fibers are commonly used in knitted fabrics and garments to provide stretch and elastic recovery.

Most available stretch circular knit fabrics on the market are made from a single type of elastic and rigid fibers. These fabrics are widely known as comfort fabrics because they can be more easily deformable and/or elastic during operation. The wearing comfort of garments made from these knit fabrics comes from its stitch rearrangement and elastic fiber extension. However, knit stitch realignment and recovery with single elastic fibers is generally imperfect because the yarns do not provide adequate restoring force to realign the stretched knit stitches. As a result, single elastic knit fabrics can experience permanent deformation or 'sacking' in certain areas of the garment, such as at the elbows of shirt sleeves, where more stretch occurs. Consumers therefore find problems with baggy and sagging after wearing them for long periods of time. Due to the loop structure, circular knit fabrics exhibit lower holding power due to higher strain compared to woven fabrics, limiting the penetration of the circular knit into the weight of the floor.

To improve the recovery performance of circular knit fabrics, it is now common to weave together larger amounts of accompanying hard yarns and spandex fibers. Higher spandex content provides higher elasticity levels and better resilience to the fabric. However, higher spandex content causes other quality issues such as high fabric shrinkage, edge curling, and rubbery feel. It is difficult to obtain a fabric with easy elasticity, high recovery, low shrinkage and good stability.

Another potential problem is see-through issues with knit fabrics, especially when worn with short pants such as yoga pants. Such fabrics may become too thin and therefore see-through when the wearer bends or stretches, revealing the wearer's underwear and/or body parts. This problem can be difficult to detect when the wearer is simply standing. This issue is often not apparent until the wearer is in a yoga pose or stretching before exercising.

Polyester bi-component filaments are elastic filaments based on polyester fibers that have moderate elasticity, excellent recovery, and other desirable fiber properties. It is used extensively in woven fabrics. However, when used in knitted fabrics, they tend to produce severely and randomly uneven surfaces that make the feel as well as the appearance of the fabric undesirable.

Therefore, there is a need to produce garments that are easy to stretch, easy to process, have low shrinkage, and are friendly, and to manufacture stretch knit fabrics that have excellent resilience, good feel and appearance, and excellent thermal insulation properties.

Aspects of the present invention relate to a method of making a stretch circular knit fabric comprising elastomeric fibers and polyester bi-component filaments.

In a non-limiting embodiment of one of the methods of the present invention, two sets of different elastic fibers are knitted together to form a single layer circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex includes bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the polyester bi-component filament has a count of 15 dtex to 900 Dtex. In this non-limiting embodiment, the knitted fabric includes 100% elastic yarn and no hard fibers are present within the knitted fabric.

In another non-limiting embodiment of the method of the present invention, the fabric further comprises hard fibers. In this non-limiting embodiment, the elastomeric fibers may be bare elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber yarn has a count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In another non-limiting embodiment of the invention, two sets of elastic fibers with different properties and hard fibers are knitted together to form a double layer circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber has a yarn count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In yet another non-limiting embodiment of the method of the present invention, two sets of elastic fibers with different properties and hard fibers are knitted together to form a double layer spaced circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes exposed elastomeric yarn comprising spandex. In one non-limiting embodiment, the spandex is bare spandex yarn having a count of 11 to 560 dtex. In this non-limiting embodiment, the present polyester bi-component filaments are placed into the center of the spaced apart fabric as cushion yarns.

Another aspect of the invention relates to a stretch circular knit fabric comprising elastomeric fibers and polyester bicomponent filaments. Various types of circular knit fabrics may be used, including, but not limited to, single jersey, float jersey, ribbed and spaced fabrics. Additional processing of the fabric may include, but is not limited to, scouring, bleaching, dyeing, drying, sanforizing, thinning, de-sizing, mercerizing, and any combination of these steps.

In one non-limiting embodiment, the fabric is a single-layer circular knit fabric formed by knitting two sets of different elastic fibers together. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex includes exposed spandex yarns having a count of 11 to 560 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex. In this non-limiting embodiment, the knitted fabric includes 100% elastic yarn and no hard fibers are present within the knitted fabric.

In another non-limiting embodiment, the stretch circular knit fabric further includes hard fibers. In this non-limiting embodiment, the elastomeric fibers can be bare elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber yarn has a count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In another non-limiting embodiment of the invention, the fabric is a double layer circular knit fabric formed by knitting together two sets of elastic fibers with different properties and hard fibers. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber has a yarn count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In yet another non-limiting embodiment, the fabric is a double layer spaced circular knit fabric formed by knitting together two sets of elastic fibers with different properties and hard fibers. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In this non-limiting embodiment, the present polyester bi-component filaments are placed into the center of the spaced apart fabric as cushion yarns.

Another aspect of the invention relates to garments produced from the fabric of the invention.

1 is a schematic diagram of a non-limiting embodiment of the fabric of the invention showing a plated knit stitch comprising elastomeric fibers, polyester bicomponent filaments and hard yarns.
Figure 2 is a schematic diagram of a portion of a circular knitting machine fed with a rigid yarn feed, a polyester bi-component filament feed, and a spandex yarn feed in the production of a non-limiting fabric embodiment of the invention.
Figure 3 is a schematic diagram of a portion of a circular knitting machine fed with a polyester bi-component filament feed and a spandex yarn feed in the production of another non-limiting fabric embodiment of the invention.
Figure 4 is another schematic diagram of a portion of a circular knitting machine fed with a polyester bi-component filament feed and a spandex yarn feed in the production of a non-limiting fabric embodiment of the invention. In this embodiment, polyester bi-component filament and spandex yarn are fed together and combined on a knit needle.
Figure 5 is a schematic diagram of a non-limiting embodiment of the fabric of the invention showing a 1X1 rib knit stitch comprising elastomeric fibers and polyester bi-component filaments.
Figure 6 is a schematic diagram of a non-limiting embodiment of a double knit fabric produced in accordance with the present invention.
Figure 7 is a schematic diagram of a fabric spaced with polyester bi-component filaments in the center.
Figure 8 is a flow diagram illustrating a non-limiting example of finishing steps that may be used on a two elastic yarn circular knit fabric made in accordance with the present invention.

Provided by the present disclosure is a stretch circular knit fabric containing two sets of different elastic fibers with improved anti-see-through, high retention and recovery properties and a method of producing the same.

The elastic circular knit fabric of the present invention includes elastomeric elastic fibers and polyester bi-component filaments and optionally hard yarns. The fabrics of the present invention are produced by knitting two sets of different elastic fibers and optionally hard yarns together by various methods and in various embodiments.

The first set of fibers used in the fabrics of the present invention include elastomeric fibers.

As used herein, “elastomeric fiber” or “elastomeric elastic fiber” refers to either a diluent-free, continuous filament or a plurality of filaments having an elongation at break greater than 100% independent of any crimp. it means. In one non-limiting embodiment, the elastomeric fibers include coalesced multifilaments. The elastomeric fiber (1) is stretched to twice its length; (2) held for 1 minute; and (3) when released, retracts to less than 1.5 times its initial length within 1 minute of release. As used herein, “elastomeric fiber” or “elastomeric elastic fiber” means at least one elastomeric fiber or filament. Examples of elastomeric fibers useful in the present invention include, but are not limited to, rubber filaments, their component filaments and elastomers, lastol, and spandex.

“Spandex” is a manufactured filament in which the filament-forming substance is a long-chain synthetic polymer composed of at least 85% by weight segmented polyurethane.

An “elastomer” is a manufactured filament whose fiber-forming substance is a long chain synthetic polymer composed of at least 50% by weight aliphatic polyether and at least 35% by weight polyester.

A "bi-component filament" is a continuous filament comprising at least two polymers attached to each other along the length of the filament, each polymer being of a different general class, for example, elastomeric polyether, lobes or wings. It has an amide core and a polyamide shell.

“Rastol” is a fiber of a crosslinked synthetic polymer of low but significant crystallinity, consisting of at least 95 weight percent ethylene and at least one other olefin unit. This fiber is elastic and substantially heat resistant.

In one non-limiting embodiment, the elastic fibers include exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex includes exposed spandex yarns having a count of 11 to 560 dtex.

Non-limiting examples of spandex useful in the present invention include Lycra® (registered trade name of Invista S. a r.l.) types 162, 169, 275 and 562.

In one non-limiting embodiment, the elastomeric fiber has a denier between 10 denier and 450 denier.

The second set of fibers used in the fabrics of the present invention include polyester bi-component filaments.

“Polyester bi-component filament” is a continuous filament composed of two polymers of different chemical or physical properties extruded from the same spinneret with both polymers in the same filament. In one non-limiting embodiment, the present polyester bi-component filaments include poly(trimethylene terephthalate) (PTT), poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate), and poly( tetramethylene terephthalate) or combinations of such members, and has a post-heat-set crimp shrinkage value of about 10% to about 80%. These yarns develop additional crimp when exposed to hot, wet conditions.

A non-limiting example of a polyester bi-component filament useful in the present invention is LYCRA® T400® fiber. LYCRA® T400® fiber is manufactured by Invista, S. a. r. It is a commercial polyester bi-component filament manufactured by L.

It is a melt spun side-by-side multicomponent filament of PTT/PET manufactured by a bonded fiber spinning process. LYCRA® T400® fibers develop crimp due to the following reasons: (1) asymmetric distribution of the two components in the fiber cross section, and (2) differential shrinkage of the PTT and PET components when the fiber is heat treated. Off-package crimp is approximately one-third of the total crimp outside the fabric. Most of the remaining crimps occur in hot, humid environments such as fabric dyeing and finishing processes.

In one non-limiting embodiment, the polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In one non-limiting embodiment, the bicomponent filament denier is from about 10 to about 450.

In one non-limiting embodiment, the knitted fabric includes 100% elastic yarn and there are no hard fibers outside the knitted fabric.

The elastomeric fiber content of the circular knit fabric having two elastic yarns is about 3% or more, including about 8% to about 35%, and about 10% to about 30%, based on the weight of the fabric. The polyester bi-component filament content in the fabric may be at least about 5 weight percent, including about 10% to about 60%, based on the total fabric weight.

In another non-limiting embodiment of the invention, the fabric further comprises hard yarns.

As used herein, “hard yarns” include knitting yarns that do not contain a large amount of elastic stretch, such as, but not limited to, linen, silk, olefin, cotton, wool, cellulosic fibers, polyester filaments, and nylon filaments. it means. Textured polyester and nylon filaments are preferred. These hard yarns provide the opportunity to add additional functionality to the fabric. For example, polyester and nylon filaments will increase the tenacity of cotton fabrics and improve their anti-wrinkle ability. Cotton and wool yarns increase moisture in synthetic fabrics. Special technicians may also be introduced. For example, Coolmax® fibers may be used, which help absorb moisture from the body and quickly transfer it to the outer or conductive fibers that conduct electricity. Fibers with microcapsules that are antibiotic can also be used to provide body care, freshness and easy care properties to the fabric. Fibers with improved thermal performance can also be used, such as THERMOLITE® fibers, which increase heat resistance and thermal insulation, and THERMOLITE® IR fibers, which generate heat under infrared light. Soft hand fibers such as micro-denier polyester and cotton-touch Supplex® nylon fibers can be employed to improve the hand feel and appearance of the fabric.

In one non-limiting embodiment, the hard fiber yarn has a count of 10 to 900 dtex.

In one non-limiting embodiment of the invention, the hard yarns are incorporated into the fabric through pre-coated elastic yarns or pre-coated yarns.

As used herein, a “pre-coated elastic yarn” or “pre-coated yarn” is one that is surrounded by, twisted with, or kneaded with a hard yarn prior to the core spinning process. The hard-yarn covering serves to protect the elastomeric fibers from grinding during the weaving process. This grinding can break the elastomeric fibers, resulting in process disruption and unwanted fabric non-uniformity. Additionally, the coating helps stabilize the elastic behavior of the elastomeric fibers so that the draw of the pre-coated elastic yarn can be more uniformly controlled during the spinning process than is possible with exposed elastomeric fibers. Pre-coated yarns can also increase the tensile modulus of yarns and fabrics, which helps improve fabric resilience and dimensional stability.

Non-limiting examples of pre-coated yarns include: (a) single wrapping of elastomeric fibers with hard yarns; (b) double wrapping of elastomeric fibers with hard yarns; (c) continuously covering the elastomeric fibers with staple fibers (i.e. corespun or core-spinning) and then twisting during winding; (d) kneading and entangling the elastomer and hard yarn with air jets; and (e) twisting the elastomeric fiber and hard yarn together.

The fabric of the invention comprising two sets of elastic fibers, elastomeric elastic fibers and polyester bicomponent filaments, and optionally hard yarns, can be produced by circular knitting.

As used herein, the term “circular knit” refers to a form of weft knitting in which knitting needles are organized into a circular knit bed. Typically, a cylinder rotates and interacts with a cam to move the needles in a reciprocating motion for the knitting action. The yarn to be knitted is supplied from the package to a carrier plate that directs the yarn strands to the needles. Circular knit fabric emerges from the knitting needles in a tubular form through the center of the cylinder. Seamless knit machines and flat knit machines are also included in this innovation.

Circular knit, flat knit and Santoni seamless machines can be used to produce these circular knit fabrics containing two sets of different elastic yarns with high stitch formation accuracy. When using the Santoni smoothing machine, two different sets of elastic yarns with draft and draft ratio can be used in different parts of the garment. The garment uses two elastic yarns with progressive compression to enhance body anatomy. The Santoni Smooth machine has the ability to produce panels shaped from two elastic yarns. A variety of fabric structures and garments can be produced in a variety of diameters on circular knitting machines. To modify the shape of the tube, the stitch structure, including, but not limited to, the tucks, floating and false ribs, and length of the stitch, and imbalance of said structure are used.

Various embodiments of the fabric of the present invention can be produced.

In one non-limiting embodiment, two sets of different elastic fibers are knitted together to form a single layer circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex includes exposed spandex yarns having a count of 11 to 560 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex. In this non-limiting embodiment, the knitted fabric includes 100% elastic yarn and no hard fibers are present within the knitted fabric.

In another non-limiting embodiment, the fabric further includes hard fibers. In this non-limiting embodiment, the elastomeric fibers can be bare elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber yarn has a count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filament has a count of 15 dtex to 900 Dtex.

In another non-limiting embodiment of the invention, two sets of elastic fibers and hard fibers with different properties are knitted together to form a double layer circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes exposed elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In one non-limiting embodiment, the hard fiber has a yarn count of 10 to 900 dtex. In one non-limiting embodiment, the present polyester bi-component filaments have a count of 15 dtex to 900 Dtex.

In yet another non-limiting embodiment of the method of the present invention, two sets of elastic fibers and hard fibers with different properties are knitted together to form a double layer spaced circular knit fabric. In this non-limiting embodiment, one set of elastic fibers includes polyester bi-component filaments and the second set of elastic fibers includes bare elastomeric yarns. In one non-limiting embodiment, the exposed elastomeric yarn includes exposed elastomeric yarn comprising spandex. In one non-limiting embodiment, the spandex is a bare spandex yarn having a count of 11 to 560 dtex. In this non-limiting embodiment, the present polyester bi-component filaments are placed into the center of the spaced apart fabric as cushion yarns.

Non-limiting fabric embodiments of the invention and methods of producing them are presented in Figures 1-7.

For example, Figure 1 is a schematic diagram of a non-limiting embodiment of a circular knit fabric with two sets of elastomeric yarns, wherein the first set is elastomeric yarns ( 12 ) and the second set is polyester bicomponent filaments ( 18 ). to provide. This elastic yarn is plated together with hard yarn ( 14 ). For jersey knit construction on circular knit machines, the process of co-knitting elastic fibers is referred to as “plating.” With plating, the hard yarn 14 and the two sets of elastomeric yarns 12 and 18 are knitted in parallel in a side-by-side relationship, so that the elastic yarn always remains on one side of the hard yarn, and thus the elastomeric yarn 12 is knitted in parallel. It's on one side. 1 is a schematic diagram of a plated knit stitch ( 10 ) wherein the knitted yarns include elastomeric yarns ( 12 ), polyester bi-component filaments (18 ), and rigid yarns (14).

Figure 2 shows a circular knitting machine with a series of knitting needles 22 reciprocating as indicated by arrows 24 in response to a cam (not shown) below a rotating cylinder (not shown) holding the needles. A non-limiting example of a supply location 20 is shown in schematic form. In a circular knitting machine, there are a number of these feed positions arranged in a circle so that the knitting needles carried by the transport cylinder feed individual knitting positions as they are rotated past that position. The device shown in Figure 2 can be used to produce a knitted fabric of double elastic yarns where two elastic yarns and one hard yarn have the same stitch pattern. In a non-limiting embodiment, three yarns are knitted together with the same weft. In one non-limiting embodiment, the device and yarn are used to fabricate a single stop structure as shown in Figure 1.

As shown in Figure 2, during the plating knit operation, the elastomeric yarn 12 , polyester bi-component filament 18 and rigid yarn 14 are delivered to the knitting needles 22 by a carrier plate 26 . do. This carrier plate (26) directs all three yarns simultaneously to the knitting position. Elastomeric yarn 12 , polyester bi-component filament 18 and rigid yarn 14 are introduced to knitting needles 22 to form a single jersey knit stitch 10 as shown in Figure 1.

In this non-limiting embodiment, hard yarn 14 is transferred from a wound yarn package 28 to an accumulator 30 that meters the yarn to a carrier plate 26 and knitting needles 22 . The hard yarn 14 passes over the feed roll 32 and through the guide hole 34 in the carrier plate 26 . Optionally, more than one hard yarn may be delivered to the knitting needles through different guide holes in the carrier plate 26 .

Polyester bi-component filaments ( 18 ) are transferred from the wound yarn package ( 60 ) to an accumulator ( 64 ) that meters the yarn to a carrier plate ( 26 ) and knitting needles ( 22 ). The polyester bi-component filament 18 passes over the feed roll 66 and through the guide hole 34 in the carrier plate 26 .

The elastomeric yarn 12 passes from the surface driven package 36 past the broken end detector 39 and with a change in direction roll(s) 37 is transferred to the guide slot 38 in the carrier plate 26 . The feed tension of the elastomeric yarn 12 is measured between the detector 39 and the drive roll 37 , or alternatively between the surface drive package 36 and the roll 37 if a broken end detector is not used. a guide hole 34 to present the rigid yarn 14 , polyester bicomponent filament 18, and elastomeric yarn 12 side by side (plated) in generally parallel relationship to the knitting needle 22 ; The guide slots ( 38 ) are separated from each other in the carrier plate ( 26 ).

Elastomeric yarn stretch is also referred to herein as draft as it transfers 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 elastomeric yarn supply package.

“Draft” refers to the amount of stretch applied to the elastomeric yarn. The draft of a fiber is directly related to the elongation (stretching) applied to the fiber (e.g. 100% elongation is equivalent to 2X draft, 200% elongation is equivalent to 3x draft, etc.).

The ratio of rigid yarn feed rate (meters per minute) to elastomeric yarn feed rate is typically 1.5 to 4 times (1.5X to 4X) greater and is known as machine draft. This corresponds to an elastomeric yarn elongation of 50% to 300%, or more. The feed tension in elastomeric yarn is directly related to the draft of the elastomeric yarn. This feed tension is typically maintained at a value consistent with high machine draft for elastomeric yarns. In the present invention, improved results are obtained when the total elastomeric yarn draft, as measured in the fabric, is maintained below about 5X, typically below 3X, for example below 2.5X. This draft value is the total draft of the elastomeric yarn including any drafting or drawing of the elastomeric yarn included in the supply package as spun yarn. The value of residual draft from elastomeric yarns is called the package relief, "PR", and typically ranges from 0.05 to 0.15 for elastomeric yarns used in round knit, elastic, and single jersey fabrics. The total draft of the elastomeric yarn in the fabric is therefore MD*(1 + PR), where “MD” is the knitting machine draft. Knitting machine draft is the ratio of the rigid yarn feed rate to the elastomeric yarn feed rate, both from their respective feed packages. Due to its stress-strain properties, the elastomeric yarn draft becomes larger as the tension applied to the elastomeric yarn increases; Conversely, the more the elastomeric yarn is drafted, the higher the tension in the yarn.

A typical elastomeric yarn path in a circular knitting machine is schematically shown in Figure 2. The elastomeric yarn 12 is metered from the supply package 36 onto or through the broken end detector 39 through one or more diverting rolls 37 , which then direct the elastomeric yarn to the knitting needles 22 . It is then metered onto a carrier plate ( 26 ) that guides it into the stitch. The elastomeric yarn creates tension in the elastomeric yarn as it passes from the supply package onto each device or roller due to the frictional force imparted by each device or roller contacting the elastomeric yarn. Therefore, the total draft of the elastomeric yarn in a stitch is related to the sum of the tensions throughout the elastomeric yarn path. The elastomeric yarn feed tension is measured between the broken end detector 39 and the roll 37 shown in Figure 2. Alternatively, the elastomeric yarn feed tension is measured between the surface driven package 36 and the roll 37 if the broken end detector 39 is not used. The higher this tension is set and controlled, the greater the elastomeric yarn draft will result in the fabric, and vice versa. For example, this feed tension may range from 2 to 4 cN for 22 dtex elastomeric yarn and from 4 to 6 cN for 44 dtex elastomeric yarn on a commercial circular knitting machine. With these feed tension settings and the additional tension imposed by subsequent yarn-path friction, elastomeric yarns in commercial knitting machines will draft significantly in excess of 3X. Minimizing elastomeric yarn friction between the feed package and knit stitch helps maintain elastomeric yarn feed tension sufficiently high for reliable elastomeric yarn feeding when elastomeric yarn draft is 7X or less. To reliably feed the elastomeric yarn from the supply package to the knit stitch, the elastomeric yarn draft is typically 3x or less.

Polyester bi-component filaments ( 18 ) are also stretched or drafted before entering the knitting needles ( 22 ). The yarn is connected to the accumulator ( 64 ) and the carrier plate ( 26 ) and In turn, the knit stitches are stretched through speed differences between them. The ratio of stitch use rate to feed rate from accumulator 64 (meters per minute) is typically 1.01X times to 1.35X times (1.01X to 1.35X). Adjusting the speed of accumulator 64 provides the desired draft or stretch ratio. If the elasticity ratio is too low, it will result in low quality fabric with grin-through. An elasticity ratio that is too high will result in breakage of the polyester bi-component filament.

“Green-through” is a term used to describe the visible exposure of elastic yarns in a fabric. Green-through itself can appear as an undesirable glint. If a choice must be made, low green-through on the facing side is preferable to low green-through on the back side.

Figure 3 provides a schematic diagram of an alternative feed system for production of the fabric of the invention. In this non-limiting embodiment, the polyester bi-component filament ( 18 ) is transferred from the wound yarn package ( 60 ) to an accumulator ( 64 ) that meters the yarn to the carrier plate ( 26 ) and knitting needles ( 22 ). do. The polyester bi-component filament ( 18 ) passes on the supply roll ( 66 ) and through the guide hole ( 34 ) in the carrier plate ( 26 ). The elastomeric yarn 12 passes from the surface driven package 36 past the broken end detector 39 and with a change in direction roll(s) 37 is transferred to the guide slot 38 in the carrier plate 26 . Guide holes 34 and guide slots 38 are provided in a carrier plate 26 to present polyester bi-component filaments 18 , and elastomeric yarns 12 side by side in generally parallel relationship to knitting needles 22 . are separated from each other.

In this embodiment, the hard yarn 14 is fed into the machine by means of a separate carrier plate and separate knitting needles. In this way, it is possible to manufacture fabrics from hard yarns only in selected courses. In other courses there are only two elastic yarns. This embodiment provides more opportunities to manufacture a variety of circular knit fabrics. All three yarns do not need to be present in every course within the fabric.

Figure 4 provides a schematic diagram of yet another alternative feeding system for the production of the fabric of the invention. In this non-limiting embodiment, both the polyester bi-component filament ( 18 ) and the elastomeric yarn ( 12 ) are merged together directly at the knitting needles without prior merging in the carrier plate ( 26 ). This embodiment provides additional flexibility for knit designers to develop different styles and different pattern fabrics, such as, but not limited to, Santoni seamless machines.

As shown in Figure 5, two sets of elastic yarns can also be used to produce the elastic circular knit fabric used in the production of the stretch fabric rib fabric. Figure 5 shows elastomeric fiber ( 12 ) and a diagram of such fabrics made from polyester bi-component filaments ( 18 ). The ribbed fabric 40 is manufactured on two needle beds with the needles in a staggered formation. The loops are drawn in opposite directions, so the front and back loops alternate in each course. Only the front loops appear on both sides of the fabric. The back loop is exposed only when the fabric extends across the width. The ribbed fabric with two elastic fibers is highly extensible in the width direction and is flat without curling. These can be used for pullovers, vests, socks, underwear and collars.

Additionally, as shown in Figure 6, two sets of elastic yarns can be used in the production of a double layer knit fabric made on a two needle bed circular knit machine. Figure 6 shows a diagram of such a fabric. The double knit fabric 82 includes a first layer Face I 84 and a second layer Face II 86 , which layers are held together by a series of interlocking yarns 88 . Interlocking yarns hold the fabric layers in spacer relationship to each other.

Additionally, as shown in Figure 7, two sets of elastic yarns can be used in the production of a double layer spaced apart knit fabric. Figure 7 illustrates this fabric structure ( 94 ). Polyester bi-component filaments, such as LYCRA® T400® fibers ( 96 ), are inserted between the two layers ( 84 and 86 ) of the fabric ( 94 ) as cushion yarns. Under heat and high temperature conditions during the fabric finishing process, the polyester bi-component filaments are wound along the fabric thickness and expand. These give the fabric elastic/cushioning properties in all directions. Polyester bi-component filaments also allow the fabric to have more open space between the two layers, resulting in higher thermal insulation. Interlocking yarns ( 88 ) and polyester bi-component cushioning yarns ( 96 ) hold the fabric layers in spacer relationship to each other.

Additional exemplary steps for finishing elastic round-knit fabrics produced according to the invention are illustrated in Figure 8. After the fabric has been knitted ( 42 ), most of the tube forms are collected under a knitting machine, either as a roll on a rotating mandrel, as a flattened tube, or in boxes after it is loosely folded back and forth. In open-width finishing, the knitted tube is then slit open ( 44 ) and laid flat. Open fabrics are subsequently relaxed by wetting them by applying steam or by soaking and squeezing, also called padding ( 46 ). The relaxed fabric is then applied to a tenter frame and heated in an oven for heat setting ( 46 ). The tenter frame holds the fabric at the edges by pins and stretches the fabric both lengthwise and widthwise to return the fabric to the desired dimensions and basis weight. If wet, dry the fabric first. Heat setting is then achieved before the subsequent wetting step. As a result, heat fixation is often referred to as “pre-fixation.” At the oven exit, the flat fabric is released from the stretcher and then fixed back into a tubular shape, referred to as sutured ( 48 ). The fabric is then processed into tubular forms through a wet process of washing, scouring, and selective bleaching/dying ( 50 ), for example by soft-flow jet equipment, and then dewatered, for example by squeeze rolls or centrifuges. ( 52 ). The fabric is then de-fixed by removing the sewing thread and reopening the fabric into a flat sheet ( 54 ). The still wet, flat fabric is then dried in a tenter-frame oven under conditions of fabric overfeed opposite the stretching, so that the fabric is under no tension in the longitudinal or machine direction while drying at a temperature below the heat setting temperature. ( 56 ). The fabric is slightly stretched across the width to flatten any potential wrinkles. Optional fabric finishes, such as softeners, may be applied immediately prior to the drying process ( 56 ). In some cases the fabric is first dried by belt or tenter-frame oven and then the fabric finish is applied, so that the finish is uniformly taken on by the equally dried fibers. This additional step involves re-wetting the dried fabric to the finish and then drying the fabric again in a tenter-frame oven.

Single layer knit fabrics formed according to the present invention by knitting together elastomeric fibers and polyester bicomponent filaments exhibit a combination of good elasticity, excellent recovery, good hand feel and good appearance. Elastomeric fibers provide the fabric with a high level of stretch that allows the fabric to stretch easily and provide comfort to the wearer. In contrast to elastomeric yarns, polyester bi-component filaments have a higher elastic modulus. Under the same loading force, polyester bi-component filaments stretch less than elastomeric yarns, thus inhibiting the elongation of the fabric and preventing the fabric from overstretching. Polyester bi-component filaments also have higher resilience than bare elastomeric fibers. Accordingly, the circular knit fabric of the present invention with two different sets of elastic fibers provides soft feel, easy movement, high flexibility, high elastic modulus and good shape retention. Polyester bi-component filaments provide high resilience and low fabric growth, while low modulus elastomeric yarns provide the fabric with easy stretch and low shrinkage, resulting in a fabric with easy stretch, high retention, and high dimensional stability. causes

The inventors have also discovered herein that a circular knit fabric with two sets of different elastic fibers can be produced with a flat surface and reduce the uneven appearance and gloss resulting from the polyester bi-component. In knit fabrics containing only polyester bi-component fibers as stretch engines without elastomeric fibers, the bi-component fibers develop a high frequency spatial helical crimp geometry similar to the appearance of a telephone wire. These crimps provide exceptionally good elasticity and crease recovery as well as bulk for yarns and fabrics. However, these crimps create a severely uneven appearance that prevents penetration of the polyester bi-component in knit applications. The inventors herein have discovered that by adding elastomeric fibers into the fabric, the non-uniformity of polyester bi-component crimp is greatly improved. The fabrics of the invention exhibit a flat surface and a softer feel.

In one non-limiting embodiment of the production of the fabric of the invention, two elastic fibers are stretched to different drafts of their initial length during the knitting process. The draft of the elastomeric fiber may be selected between 1.8X and 5.0X times the draft, while the draft of the polyester bi-component filament may be selected between 1.01X and 1.35X times the draft. For two elastic fibers with different denier or different filament counts, the elasticity ratios of the polyester bi-component filaments and the elastomeric microgroups can be different from each other depending on the requirements of the desired elastic fiber performance and fabric quality. In many cases, elastomeric fibers draft more, providing high stretch performance, while polyester bi-component filaments stretch less, providing low shrinkage and high resilience to the fabric.

In one non-limiting embodiment, the two sets of elastic fibers not only have different polymer compositions but also have different stress-strain behavior and different thermal behavior. For example, in one non-limiting embodiment, the fabric may include spandex fiber LYCRA® Fiber T162B as the elastomeric yarn and LYCRA® T400® polyester bi-component filament as the polyester bi-component filament. . In another non-limiting embodiment, the two sets of elastomeric yarns may have different heat set efficiencies, such as LYCRA® T400® fiber heat set at a temperature of 365°F degrees and T162B LYCRA® fiber heat set at 380°F degrees. In this non-limiting embodiment, if the fabric is heat set at a temperature higher than the LYCRA® T400® fiber heat set temperature, but lower than the LYCRA® fiber T162B heat set temperature, the fabric exhibits good elasticity as well as acceptable fabric shrinkage. and receives only partial heat fixation to provide growth.

Another advantage of the fabrics of the present invention is that the polyester bi-component filaments have better resistance to chemical and/or environmental factors than elastomeric fibers such as spandex. For example, polyester bi-component filaments have better resistance to both chlorine and UV light compared to spandex. Accordingly, the fabrics of the present invention perform well in chlorine-containing pools as swimwear and other outdoor clothing exposed to UV light.

In some embodiments of the invention, the fabric consists solely of elastic fibers containing both elastomeric fibers and polyester bicomponent filaments. Since no hard fibers are present in this embodiment, this fabric exhibits excellent flexibility and superior resilience. This fabric embodiment is also highly breathable and lightweight. This fabric embodiment is therefore ideal for garments that require high retention, full recovery and breathability, such as, but not limited to, bra wings, comfortable body shaping garments and sportswear.

The method of the present invention has been found to be particularly useful for producing single layer jersey fabrics with good quality terry jersey fabric structure. Terry jersey or float jersey is a knit fabric featuring a float stitch or soft yarn pile on one side of the fabric, resulting in a very absorbent, moisture-wicking material. Some types of float jersey fabrics are heavier than a t-shirt, but are lighter than most sweatshirts and have good elasticity, making them very comfortable to wear. Other types of float jersey fabrics have a flat, clean appearance on both sides of the fabric with strong resilience. Terry jersey fabrics typically have higher elasticity and higher resilience than single jersey fabrics in all directions.

Terry jersey fabric can be knitted according to the invention by using two sets of different elastomeric yarns arranged alternately in the wale direction. A first set of yarns, referred to as loop yarns, are knitted into a single jersey in each wale. A second set of yarns, referred to as float yarns, are knitted into float loops and interlocked with the first set of loop yarns. The float yarn may float on various wales, such as one wale, two wales, or more wales. In the fabric of the present invention, either elastomeric fibers or polyester bi-component filaments can be used in either loop yarns or float yarns, or they can be used together in both loop yarns and float yarns. In one non-limiting embodiment, hard yarns can also be incorporated into loop yarns and/or float yarns. The elastic fibers used in the present invention stretch more easily and have higher resilience in a float loop structure with flat fiber segments.

The fabrics of some embodiments of the invention exhibit an elongation of about 20% to about 200% in the warp and/or weft directions. Additionally, such fabrics may have a shrinkage during washing in both the length and width directions of less than about 15%, such as less than 7%. The fabric may have a weight of 100 grams/meter ² to 600 grams/meter ² . Additionally, the stretch fabric can have excellent hand feel. In this embodiment, the fabric stretch level of the fabric is at least 15% in both the warp and weft directions.

The invention also relates to garments made from the fabrics described herein. Although the properties of these fabrics make them particularly useful in casual and leisure wear garments, seamless fabrics comprising two different sets of two elastic yarns are also useful in outerwear. Additionally, the ability to change the denier and knit pattern of elastic yarns makes these fabrics useful in specific areas of many garments. For example, fabrics of the present invention comprising heavier deniers and higher drafts of elastomeric yarns can be incorporated into garments to have better retention in certain critical areas such as the knees, inner thighs, and front panels of pants. Therefore, it is possible to manufacture garments with higher molding function and high deformability. In other areas, fabrics of the invention with lower elasticity and deformation can be used and thus provide better comfort. Therefore, the fabric of the present invention is particularly useful for manufacturing all types of good quality, comfortable garments with spot forming capabilities in critical areas. Non-limiting examples of garments that can be made from the fabrics of the present invention include sportswear, activewear, swimwear, bras, underwear, comfort wear, leggings, outerwear, and shoe fabrics.

The sections below provide additional examples of fabrics and methods of their production. This example is illustrative only and is not intended to limit the scope of the invention in any way.

Analysis method

Yarn restoreable elasticity

The recoverable elasticity of the elastic fibers used in this example was measured according to ASTM D6720-07. Each yarn sample was formed into a skein of 5000 +/-5 total denier (5550 dtex) on a skein reel at a tension of approximately 0.1 gpd (0.09 dN/tex). The skein was then immersed in water at 100°C for 15 minutes, after which the skein was removed from the water. The skeins were then conditioned at 70°F (+/-2°F) ( ²¹⁰ +/-1°C.) and 65% (+/-2%) relative humidity for at least 16 hours to air dry.

The skein was hung substantially vertically on a stand. After cycling three times with a 1030 gram hanging weight, a 1030 gram weight (206 mg/d; 185.4 mg/dtex) is suspended from the bottom of the skein, and the length of the skein is measured to the nearest 1 mm and "L ₁ " It was recorded as Next, a 6 mg/den (5.4 mg/dtex) weight (e.g., 30 grams for a 5550 dtex skein) is suspended on the bottom of the skein, the weighed skein is brought to equilibrium length, and the skein length is 1 Measured to within mm and written as "L ₂ ". "CC _a ", the yarn recoverable elasticity (percent), was calculated according to the formula CC _a (%) = 100 * (L ₁ -L ₂ )/L ₂ .

Draft of elastic yarn

The following procedure was used to measure elastic yarn draft in the examples. Yarn samples with more than 200 stitches (needles) are marked with the beginning and end of the 200 stitches, de-knitted or unwound from a single course, and the elastic and hard yarns of these samples are separated.

Each sample (elastic yarn or hard yarn) was then hung freely by gluing one end onto a meter stick with one mark on the top of the stick. A weight was attached to each sample (0.1 g/denier for hard yarn and 0.001 g/denier for spandex). The weight was lowered slowly to ensure that the weight was applied to the ends of the yarn sample without impact. The length measured between the marks was recorded. Measurements were repeated for five samples each of elastic and rigid yarns. The average draft was calculated according to the formula: draft = (length of hard yarn between marks) ÷ (length of elastic yarn between marks).

Elastomeric fiber content

The knit fabric was weighed and then de-knitted by hand. The elastomeric fibers were separated from the accompanying hard yarn and weighed on a precision laboratory balance or torsion balance. Elastomeric fiber content is expressed as a percentage of elastomeric weight relative to fabric weight.

Fabric elongation (elasticity)

Fabrics were evaluated for % elongation under a specified load ( i.e. , force) in the direction(s) of stretching of the fabric ( i.e. , weft, warp, or weft and warp), which is the direction of the composite yarns. Three samples measuring 60 cm x 6.5 cm were cut from the fabric. The long dimension (60 cm) corresponds to the stretching direction. The sample was partially unwound to reduce the sample width to 5.0 cm. The samples were then conditioned at 20°C +/- 2°C and 65% relative humidity +/- 2% for at least 16 hours.

A first reference point was taken across the width of each sample at 6.5 cm from the sample end. A second reference point was performed over the sample width at 50.0 cm from the first reference point. The excess fabric from the second reference point to the other end of the sample was used to form and stitch a loop into which a metal pin could be inserted. A notch is then cut into the loop so the weight can be attached to the metal pin.

The sample non-loop ends were fixed and the fabric sample was hung vertically. By attaching a 17.8 Newton (N) weight (4 LB) to a metal pin through a suspended fabric loop, the fabric sample was stretched by the weight. The sample was “trained” by allowing it to be stretched by a weight for 3 seconds. The force was then relieved manually by lifting a weight. This cycle was performed three times. The weight is then allowed to hang freely, thus stretching the fabric sample. The distance in millimeters between two reference points was measured while the fabric was under load. This distance is designated ML. The initial distance ( i.e. , uncaged distance) between reference points was designated GL. The % fabric elongation for each individual sample is calculated as follows:

% Elongation (E%) = ((ML-GL)/GL) x 100

The three elongation results were averaged for the final result.

Fabric growth (new, unrestored)

After stretching, the fabric without growth returns exactly to its original length before stretching. However, typically, stretch fabrics will not fully recover and will become slightly longer after prolonged stretching. This slight increase in length is referred to as “growth.”

The fabric elongation test must be completed prior to the growth test. Only the stretching direction of the fabric was tested. For 2-way stretch fabrics, both directions were tested. Three samples of 55.0 cm x 6.0 cm each were cut from the fabric. These were different samples than those used in the elongation test. The 55.0 cm direction must coincide with the stretching direction. The sample partially unraveled, reducing the sample width to 5.0 cm. Samples were conditioned at the same temperature and humidity as in the elongation test above. Two reference points exactly 50 cm apart were drawn across the width of the sample.

A known % elongation (E%) from the elongation test was used to calculate the length of the sample at 80% of this known elongation. This was calculated as follows

E (length) at 80% = (E%/100) x 0.80 x L,

where L was the initial length between reference points ( i.e. , 50.0 cm). Both ends of the sample were fixed and the sample was stretched until the length between the reference points was L + E (length) as calculated above. This stretching was maintained for 30 minutes, after which the stretching force was released and the sample was allowed to hang freely and relax. After 60 minutes the % growth was measured as follows:

% growth = (L2 x 100)/L,

where L2 was the increase in length between sample reference points after relaxation, and L was the initial length between reference points. This % growth was measured for each sample and the results were averaged to determine the growth number.

fabric restoration

Fabric recovery means that a fabric is able to restore its original length after deformation from stretching or tension stress. It is expressed as the percentage ratio of the increased extended length of the fabric under tension relative to the length of the fabric upon stretching or release of the tension stress. This can be calculated from fabric stretch and fabric growth.

fabric shrinkage

Fabric shrinkage was measured after washing. The fabric was first conditioned at the same temperature and humidity as in the elongation and growth tests. Two samples (60 cm x 60 cm) were then cut from the fabric. Samples were taken at least 15 cm from the edge. A four-sided box measuring 40 cm x 40 cm was marked on the fabric sample.

The samples were washed in a washing machine with sample and loaded fabrics. The total washer load was 2 kg of air-dried material, and less than half of the wash consisted of test samples. The laundry was gently washed and spun at a water temperature of 40°C. Depending on the hardness of the water, an amount of detergent ranging from 1 g/l to 3 g/l was used. Samples were placed on a flat surface until dry and then conditioned at 20°C +/- 2°C and 65% relative humidity +/- 2% rh for 16 hours.

Fabric sample shrinkage was then measured in the warp and weft directions by measuring the distance between marks. Shrinkage after washing, C% was calculated as follows:

C% = ((L1 - L2)/L1) x 100,

where L1 is the initial distance between the marks (40 cm) and L2 is the distance after drying. Results are averaged over the samples and reported for both warp and weft directions. Negative shrinkage numbers reflect expansion, which was possible in some cases due to hard yarn behavior.

fabric weight

Knit fabric samples were die-punched with 10 cm diameter dies. Each cut knit fabric sample was weighed in grams. “Fabric weight” was then calculated in grams/square meter.

fabric resilience

The fabric was cut to 3X8 inches. Using a fabric marking pen, a reference point "A" was drawn 1 inch from one edge of each sample. Reference point "B" was drawn 6 inches from reference point "A", resulting in two reference points 6 inches apart. The fabric sample was then sewn into a loop by folding the two short edges together so that the reference points were aligned and a straight seam was sewn across the marks. The test loop was conditioned for at least 16 hours at 70°F temperature and 65% relative humidity. Samples were trained on an Instron machine by cycling three times with extension and release at 75% elongation rate and 200% per minute. The fabric unloading force at 30% elongation in the third cycle was recorded as fabric recovery force. Fabric resilience refers to the ability of a fabric to recover while worn.

Example

The following non-limiting examples demonstrate the invention and its ability for use in making a variety of fabrics. The invention is capable of other and different embodiments, and its several details may be modified in various obvious respects without departing from the scope and spirit of the invention. Accordingly, the examples are to be regarded as illustrative in nature and not restrictive.

For examples, a 28 gauge single layer circular knit fabric with two elastic yarns plated with hard yarns was knitted Monarch circular with a 26 inch cylinder diameter, 28 gauge (needle per inch of circumference) and 2232 needles, and 42 yarn feed positions. Knitted on machine model VX-RDS. This circular knit machine was operated at 16 revolutions per minute (rpm). A 44-gauge, single-ply circular knit fabric was knitted on a Monarch circular knitting machine, model VX-3S, 30 inches in diameter, needle 4152, feeder 90, and approximate RPM 20.

The double-layer circular knit fabric was made on a Terrot circular knitting machine, model RH-216 I, cylinder diameter 18 inches, gauge 24 needles/cylinder inch of circumference. There are also 24 needles per inch on the dial, technically making this a 48 gauge, but it is called a 24, with 1356 needles in the cylinder and 1356 needles in the dial, 30 feeders and approximately 18 RPM.

The elastomeric fiber feed tension was measured between the elastomeric fiber feed package 36 and the roller guide 37 (FIG. 2) with an Iro Memminger digital tension meter, model number MER2. For the examples below, the elastomeric fiber feed tension was maintained at 4 and 7 grams for the 40 and 70-denier spandex. These tensions are sufficient for reliable and continuous supply of this elastomeric yarn of spandex to knitting needles. If the feed tension is too low, the spandex yarn wraps around the roller guide in the feed package and cannot be reliably fed into the circular knitting machine. The tension device for the polyester bi-component filament yarn and rigid yarn was an IRO Memminger with MPF40 KIF model. The tension for the polyester bi-component filament was about 8-9 grams. The tension for the hard yarn was about 6-7 grams.

Embodiment of the seamless fabric of the invention produced by circular knitting using a knitting machine from SANTONI (from GRUPPO LONATI, Italy), SMA-8-TOP seamless, 28 inch body size (hereinafter "SANTONI knitting machine") yes. Combinations of different knitting configurations using various types of yarn were used. This machine has 8 yarn feeding positions. It was operated at 70 revolutions per minute (rpm). Elastomeric fiber feed tension was measured with a BTSR® digital tension meter, model number KTF-100HP. For the examples below, the elastomer feed tension was maintained at 1 gram for each 10 denier spandex. The tension device for the polyester bi-component filament yarn and rigid yarn was an IRO Memminger with model ROJ Tricot.

The knitted fabric was preheated, washed, dyed and dried. In the case of smooth fabrics, the fabric was subjected to a finishing process without heat setting. The fabric was washed and bleached in a 100-liter solution at 100°C for 30 minutes. All wetting, jet finishing and dyeing were carried out on Thies, a horizontal jet dyeing machine with a soft flower. The fabric was treated with Domoscour LFE810 (13 g) (scouring and emulsifying agent manufactured by M.Dohmen Company), Lurotex A-25 (100 g) (hydrophilic finishing and softening agent manufactured by BASF Cooperation) at 49°C for 5 minutes. It was pre-washed with an aqueous solution.

The fabric was dyed for 60 minutes at 85°C using direct dyes and other ingredients. The dye solution contained 85.8 grams of Solorphenyl FGE 250 (from Huntsmen Corp.), 0.5 weight percent sodium phosphate tribasic (PH corrected), and 45000 grams of common salt. Then, 78 grams of Burcofix 195 (color fixative manufactured by M. Dohmen Company) and 65 grams of Ultratex MES and 10 grams of acetic acid were added into the dyeing bath and carried out at 45° C. for 30 minutes. The millet was drained and the fabric was unloaded from the container. The fabric was then dried in a tenter (Kenyon Company) oven at 145°C for approximately 30 seconds.

Table 1 lists the materials and process conditions used to make fabric samples with elastomeric and polyester bicomponent filaments. The elastic yarn used is available from Invista, s.a.r.L. of Wilmington, Delaware and Wichita, Kansas. Elastic fiber 40d heading in the column means 40 denier; 3.3X means the draft of elasticity added by the core spinning machine (machine draft). In the column titled 'Hard Yarn', 16's is the linear density of the spun yarn as measured by the English Cotton Count System. The remaining items in Table 1 are clearly labeled.

[Table 1]: List of single layer CK fabric examples

Comparative Example 1C: Comparative Knit Fabric with One Spandex

A stretch circular single jersey knit fabric of spandex fibers only was manufactured on a 28 gauge machine. This fabric is made from 30s cotton spun yarn with 40D LYCRA® spandex fiber. The draft of LYCRA® fiber was 2.7X during knitting. 30s cotton yarn was plated with LYCRA® fibers to form a single jersey fabric. This fabric has a very high stretch level of 219.2% in the width direction, but has low resilience in both the length and width directions (85.1 grams by 77.6 grams). This fabric stretches easily, but exhibits difficult recovery. Such easy deformation and difficult restoration cause garments produced from this fabric to exhibit poor ability to maintain its garment shape and dimensional stability. This garment exhibits sagging and bagging while worn. This fabric contained 7.7% LYCRA® fiber and 92.3% cotton.

Example 2: Cotton jersey fabric with two different elastic fibers

This sample had the same fabric structure as Example 1C except for the incorporation of 50D LYCRA® T400® fibers. The fabric contained two elastic yarns according to the invention: 40D LYCRA® spandex fibers and 50d/34f LYCRA® T400® polyester bi-component filaments. The cotton yarn was 50 Ne count yarn. Table 1 summarizes the test results. Apparently, this sample had good elasticity (85.3% length x 116.4% width). This fabric also had low shrinkage. This fabric also had improved resilience (205.9% length x 146.2% width). Adding polyester bi-component filaments significantly increased jersey fabric holding power and limited further stretching in the width direction, while simultaneously increasing resilience in both directions. This fabric demonstrated highly stable dimensions and strong shape retention ability. This fabric contained 4.6% LYCRA® fiber, 28.0% LYCRA® T400® bi-component fiber, and 67.4% cotton.

Example 3: Single layer knit containing double elastic fibers

This sample had the same fabric structure as Example 2 except that the denier of LYCRA® T400® fiber: 40D T162B LYCRA® fiber with 2.7X draft and 75d/34f LYCRA® T400® fiber with 1.10X draft were used. I had it. The hard yarn was a 50 Ne 100% cotton ring spun yarn with a single jersey stitch structure. The finished fabric had a weight of 6.1 oz/yard ² and elasticity of 84.5% and 118.3% in the length and width directions, respectively. The fabric resilience was 314.6 grams by 214.6 grams in the length and width directions. As shown, the high denier of LYCRA® T400® fiber helped increase fabric resilience in both directions. This fabric contains 7.6% LYCRA® fiber, 37.8% LYCRA® T400® bi-component fiber and 54.6% cotton.

Example 4: Single layer knit containing double elastic fibers

This sample was the same fabric as in Example 2 except that LYCRA® fiber: denier of 70D T162B LYCRA® fiber, 2.7X draft and 1.05X draft were used for 70D LYCRA® fiber and 75d/34f LYCRA® T400® fiber It had a structure. The hard yarn was a 50 Ne 100% cotton ring spun yarn with a single jersey stitch structure. The finished fabric had a weight of 6.5 oz/yard ² and elasticity of 100.8% and 97.3% in the length and width directions, respectively. The fabric resilience was 290.2 grams by 249.7 grams in the length and width directions. As shown herein, the high denier of LYCRA® fibers increased fabric resilience in both directions. This fabric contains 14.4% LYCRA® fiber, 26.3% LYCRA® T400® bi-component fiber and 59.3% cotton.

Example 5: Single layer jersey fabric with 100% elastic fibers

This sample was a single layer jersey fabric containing 100% elastic fibers: 40D T275B LYCRA® fibers and 50D/34f LYCRA® T400® polyester bi-component fibers. The fabric weight was 4.8 oz/yard ² with 31.4% elastomeric fibers and 68.5% polyester bicomponent fibers. Due to the absence of hard fibers, the fabric exhibits excellent flexibility and superior resilience. This fabric also has high breathability and quick drying properties. This is an ideal material for garments that require high holding power, full resilience and breathability. This is also an excellent option for a swimsuit. Polyester bi-component is chlorine resistant. In swimming pools, fabrics have better anti-chlorine performance than stretch fabrics containing only spandex fibers, which lose their resilience after prolonged exposure in swimming pools to chlorine chemicals. This fabric also still has elasticity and recovery properties in the bra cup area after modeling at high temperatures. This can provide better comfort to the bra wearer, especially sports bras.

Example 6: Single layer jersey fabric with 100% elastic fibers

This fabric had the same fabric structure as Example 5 except that the polyester bi-component filament LYCRA® T400® fibers had a denier of 30D/34f. The draft of exposed 40D LYCRA® fiber was 1.8X and that of LYCRA® T400® was 1.05X. This fabric used the same stitch structure as Example 5. Table 1 summarizes the test results. This sample also had good elasticity of 105.6% x 122.6% and good fabric recovery of 218.9 g x 309.1 g. The use of lower denier LYCRA® T400® fibers created a lighter weight fabric with a more open structure and softer feel.

Example 7: Containing two elastic fibers Single layer terry jersey fabric

This sample was a terry jersey fabric and had float loops on one side of the single knit fabric. The loop yarn was a 50D/34f polyester bi-component filament of 40D T275B LYCRA® elastomeric fiber and LYCRA® T400® fiber. The float yarns were 40D T275B LYCRA® elastomeric fiber and 40D textured nylon fiber. The face side of the fabric looks like a typical single piece jersey while the back side of the fabric has float loops with one loop skip. The float loop was formed by knitting loop stitches of loop yarn. LYCRA® fiber draft was 1.8X while LYCRA® T400® fiber draft was 1.05X. The fabric weight was 6.1 oz/yd ² and the fabric elasticity was 92.3% This fabric had a very high resilience of 211.7 g This fabric had good nylon fiber feel and LYCRA® T400® fiber power performance.

Example 8: Containing 100% elastic fibers Single layer terry jersey fabric

This sample had a float loop on one side of the single knit fabric. Both loop yarns and float yarns were 50D/34f polyester bi-component filaments of 40D T275B LYCRA® elastomeric fiber and LYCRA® T400® fiber. The face side of the fabric looks like a typical single piece jersey while the back side of the fabric has float loops with one loop skip. The float loop was formed by knitting loop stitches of loop yarn. LYCRA® fiber draft was 1.8X while LYCRA® T400® fiber draft was 1.05X. The fabric weight was 5.3 oz/yd ² and the fabric elasticity was 69.3% This fabric had a very high resilience of 329.7 g

Example 9: Containing 100% elastic fibers Single layer terry jersey fabric

This example had a similar fabric structure to Example 8. This fabric is made of 42.6% LYCRA® fiber and 57.4% LYCRA® T400® fiber with a terry structure. The difference is that 70D T275Z LYCRA® fiber was used to replace 40D T1275B LYCRA® fiber in both loop yarn and float yarn. Higher denier LYCRA® fibers ensure higher weight and greater strength of the fabric. This fabric can be used for comfortable shapewear with strong holding power.

Example 10: 1X1 Ribbed Fabric with Spandex and Polyester Bi-Component Filaments

This sample was a 1x1 ribbed fabric made from a double knit machine. 50d/34f LYCRA® T400® fiber and 40D LYCRA® fiber were plated together in each weft. Both sides of the fabric had a similar appearance. Compared to jersey fabric, this is thicker and heavier. It can only be tied at one end. This fabric was flat without curling and showed excellent transverse elasticity. This fabric is particularly useful for underwear and t-shirts. The content of LYCRA® fiber and LYCRA® T400® fiber is 23.0% and 77.0% of the inner fabric with a total weight of 7.1 oz/yard ² .

Example 11: 2X2 Ribbed Fabric with Spandex and Polyester Bi-Component Filaments

This sample was a 2X2 ribbed fabric made on a double knit machine. 50d/34f LYCRA® T400® fiber and 40D LYCRA® fiber were plated together in each weft. Both sides of the fabric had a similar appearance. Compared to jersey fabric, this sample is thicker and heavier. It can only be tied at one end. This fabric was flat without curling and showed excellent transverse elasticity. This fabric is particularly useful for t-shirt collars due to its flat, non-curling advantages.

[Table 2]. Double Layer CK Fabric Example List

Example 12: Double Layer Knit Fabric with Spandex and Polyester Bicomponent Filaments

This sample was a knit fabric manufactured on a double knit machine. The fabric has two faceins, Face A and Face B, connected together by interlocking yarns. Face A yarn is a 32S cotton spun yarn with 70D LYCRA® fiber; Face B yarn is 150D LYCRA® T400® fiber; And the interlocking yarn is 75D polyester. This fabric has a weight of 212.2 grams/m2. 70D LYCRA® fiber provided elasticity and recovery to Face A. 150d/68f LYCRA® T400® fiber provides support and resilience. Compared to single-layer knit fabrics, LYCRA® T400® fibers have more open space in double-layer fabrics, allowing LYCRA® T400® fibers to fully relax and wrap. Therefore, this fabric has high thickness and high thermal insulation properties with a CLO value of 0.31. 75D polyester filament was used as the interlocking yarn to connect the two layers together.

Example 13: Double layer knit fabric with spandex and polyester bicomponent filaments

This sample was also a knit fabric manufactured on a double knit machine. The fabric has two facets: face A and face B, connected together by interlocking yarns. Face A yarn is a 32S cotton spun yarn with 70D LYCRA® fiber; Face B yarn is 150D LYCRA® T400® fiber; And the interlocking yarn is 70D LYCRA® fiber. This fabric has a weight of 325.3 grams/m2. Two yarns of 70D LYCRA® fiber provide stretch and resilience to Face A, while the interlocking yarn 150d/68f LYCRA® T400® fiber provides support and resilience. Compared to Example 11, the 70D LYCRA® fibers in the interlocking yarn provide more strength to this double layer fabric, thus allowing all the fibers to be pulled and closed with significantly higher thickness and higher thermal insulation. This sample has a CLO value of 0.52.

Example 14: Double Layer Knit Fabric with LYCRA® T400® Fiber Cushion Yarn

This sample was a knit fabric manufactured on a double knit machine. The fabric has two facets: face A and face B, connected together by interlocking yarns. Face A yarn is a 32S cotton spun yarn with 40D LYCRA® fiber; Face B yarn is 75D COOLMAX® polyester fiber; And the interlocking yarn was 32s cotton yarn. The fabric weight was 244 grams/m2. 40D LYCRA® fiber provided stretch and recovery for Face A; 150d/68f LYCRA® T400® fiber was inserted midway between Face A and Face B to provide support and resilience. LYCRA® T400® fibers are covered on both surfaces of the fabric and are invisible on the front and back of the fabric. LYCRA® T400® fibers shrink and curl under thermal conditions during the fabric finishing process, causing the entire portion of the fabric to swell and expand through the thickness, creating a cushioned feel with high resilience through the thickness. LYCRA® T400® fibers lie at the center of the fabric and because there is more open space in this double-layer fabric, LYCRA® T400® fibers allow full relaxation and wrapping. Therefore, this fabric has high thickness and high thermal insulation properties and has a CLO value of 0.32.

Example 15: Double Layer Knit Fabric with LYCRA® T400® Fiber Cushion Yarn

This sample was a double knit fabric with two faces, an interlocking yarn and a cushioning yarn. Face A yarn was 150D Supplex® nylon filament and 70D LYCRA® fiber. Face B yarn was 75D COOLMAX® polyester fiber. 150D Supplex® nylon yarn was used as the interlocking yarn. 150d/68f T400 was plated on the center of the fabric between Face A and Face B. This increases fabric bulk and thickness with good cushioning and resilience, although not visible. This is an ideal material for winter activewear due to its good protection and warmth properties. This fabric can also be molded into bra cups with good coverage, shape retention and comfort.

Example 16: Double Layer Knit Fabric with LYCRA® T400® Fiber Cushion Yarn

This fabric was a double layer interlocking fabric with LYCRA® T400® fiber as the cushion yarn. 30s TENCEL® fiber spun yarn was used as face A and interlocking yarn. 70D LYCRA® fiber was used on both faces of the fabric. This fabric offers an exceptionally soft feel and extremely good elasticity and resilience. LYCRA® T400® fibers in the center and face B provide cushioning and a 3D effect. This fabric contains 8.3% LYCRA® spandex fiber and 11.6% LYCRA® T400® polyester bi-component fiber.

Example 17: Double Layer Knit Fabric with 75D LYCRA® T400® Fiber Cushion Yarn

This sample is a double knit fabric with two sides. Face A contained 50S TENCEL® spun yarn in all wefts and 70d LYCRA® fibers were plated in alternative wefts. Face B yarn is a 50s TENCEL® spun yarn with 70D LYCRA® fiber. 50s TENCEL® yarn was also used as interlocking yarn. 75D/34f LYCRA® T400® polyester bi-component filaments were introduced into the center of both sides to form a space. This sample is especially useful for leggings in the fall and spring seasons.

Claims (1)

Use as a garment of a stretch circular knit fabric comprising elastomeric fibers and polyester bi-component elastic filaments.

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