KR102158057B1 - Stretch yarns and fabrics with multiple elastic yarns - Google Patents

Abstract

Articles and methods comprising core spun yarns are included herein. The core spun yarn comprises a sheath of hard fibers and two sets of elastic fibers, wherein the sets of elastic fibers have different properties. The properties can be different in one or more ways, for example can have different deniers, compositions or drafts. Either or both of the sets of elastic fibers may be pre-covered.

Description

Stretch yarns and fabrics with multiple elastic yarns {STRETCH YARNS AND FABRICS WITH MULTIPLE ELASTIC YARNS}

The present invention relates to the manufacture of stretchable composite yarns and fabrics. The present invention specifically relates to fabrics and methods comprising two sets of elastic core fibers in one yarn.

Stretch fabrics with elastic composite yarns have long been commercially available. Fabric and garment manufacturers generally know how to make fabrics with the right quality parameters to achieve a fabric that is acceptable to the consumer. In currently commercially available fabrics, there is only one elastic fiber system inside the yarn and fabric. One elastic fiber provides the dual function of elasticity and recovery. Fabrics with easy stretchability, high recovery and low shrinkage performance are difficult to obtain.

Easy stretch is an important feature for a comfortable garment. For a more comfortable garment, the fabric can be easily stretched and contracted when the garment is worn and moved on the human body. These fabrics have low pressure on the body by the garment. The garment can be cut to achieve a more streamlined appearance, and can fit better to the body while still maintaining comfort from the wearer in motion. This performance can be achieved by minimizing the resistance of the garment to the demands of a moving body through a low fabric tensile modulus.

However, for fabrics with low tensile modulus, a typical quality problem is that the fabric is in its original size after the fabric is overstretched in some parts of the body such as the knees, hips and waist, especially in the case of fabrics with high elasticity levels. And it cannot be quickly recovered into shape. Typically, the fabric has low recovery power when its tensile modulus is low. Consumers suffer from loosening and sagging problems after long wear.

Conversely, in order to have a fabric with good recovery, an additional shrinking force is required in the fabric. Larger amounts or stronger elastic fibers can be added to the fabric. However, these fabrics have a high modulus of elasticity and a greater interference force. Consumers complain of increased garment pressure and uncomfortable constraints while wearing and moving. At the same time, the fabric has poor dimensional stability. Heat setting is a necessary process to control fabric shrinkage. The comfort and freedom of movement of the garment is impaired by the fabric shape shaping and recovery function. Fabrics with easy stretchability, high recovery and low shrinkage performance are still desired.

For many years, composite elastic yarns have been widely known. For example, by U.S. Patents 4470250, 4998403, 7134265, 6848151, elastomeric fibers such as spandex facilitate acceptable knitting or weaving processing, and also provide elastic composite yarns with acceptable characteristics for fabrics of various end uses. It was covered with relatively inelastic fibers to provide. In the US patent applications US 2008/0268734A1 and USA 2008/0318485A1, a rigid filament as a core inside the core spun yarn is used with an elastic filament.

Accordingly, there is a need for an elastic woven fabric having easy stretchability, easy processability, low shrinkability, friendly garment manufacturing, and excellent recovery power and low extensibility.

One aspect includes a method of making a composite yarn having two sets of different elastic core fibers, also referred to as a double elastic composite yarn. Also included are dual elastic composite yarns and stretch fabrics and garments made from such composite yarns.

According to a first embodiment of the method, two sets of elastic fibers and hard fibers having different properties are covered together to form a composite yarn, wherein the two sets of elastic fibers are drafted different to their original length during the yarn covering process. It is stretched with (draft). The elastic fiber may be a bare spandex yarn of 11 to 560 dtex, and the hard fiber has a yarn count of 10 to 900 dtex. One suitable hard yarn is cotton yarn. The elastic core fiber I and the elastic core fiber II are independently selected from elastomeric or non-elastomeric fibers.

According to a second embodiment of the method, two sets of elastic fibers (elastic core fiber I and elastic core fiber II) and hard fibers having different properties are covered together to form a composite yarn, wherein the two sets of elastic fibers are It has different polymer composition and different stress-strain behavior. The elastic fiber may be an unprocessed spandex yarn of 11 to 560 dtex, and the hard fiber has a yarn count of 10 to 900 dtex. One suitable hard yarn is cotton yarn.

According to a third embodiment of the method, two sets of different elastic core fibers (elastic core fibers I and elastic core fibers II) and hard fibers are covered together to form a composite yarn, wherein at least one set of elastic core fibers Is a pre-covering elastic yarn. Another set of elastic core yarns may be raw spandex or pre-covering elastic yarns. The raw spandex yarn denier is 11 to 560 dtex, and the hard fiber has a yarn count of 10 to 900 dtex. One suitable hard yarn is cotton yarn.

According to a fourth embodiment of the method, two sets of different elastic core fibers and hard fibers are covered together to form a composite yarn, wherein at least one elastic core fiber is a non-elastomeric elastic fiber. Another set of elastic core yarns may be raw elastomers such as spandex. The raw spandex yarn denier is 11 to 560 dtex, and the hard fiber has a yarn count of 10 to 900 dtex. One suitable hard yarn is cotton yarn.

Fabrics are made using double elastic yarns made by one of these alternatives. Double elastic yarns are used in one or more directions of the fabric. Any type of fabric can be used, including woven, circular, warp and narrow fabrics. Further processing may include refining, bleaching, dyeing, drying, sanforizing, singeing, de-sizing, polishing, and any combination of these steps. The fabricated stretch fabric can be formed into a garment.

The detailed description will be made with reference to the following figures, where like numerals denote like elements.
1 illustrates a core spun yarn having two types of elastic cores.
Fig. 2 is a schematic diagram of a core spinning apparatus having two draft mechanisms for two kinds of raw elastic fibers.
3 is a schematic diagram of a core spinning apparatus having two draft mechanisms with weighting rolls.
4 is a schematic diagram of a core spinning apparatus having two draft mechanisms for one kind of raw elastic fiber and one kind of pre-covering elastic yarn.

Elastomer fibers are commonly used in woven fabrics and garments to provide stretch and elastic recovery. “Elastomer fibers” are continuous filaments (optionally combined multifilaments) or a plurality of filaments without diluent, having an elongation at break of greater than 100% regardless of crimp. The elastomeric fibers (1) stretch to twice their length; (2) hold for 1 minute, then; (3) When relaxed, it contracts to less than 1.5 times its original length within 1 minute of relaxation. As used in the text of this specification, “elastomeric fibers” means one or more elastomeric fibers or filaments. Such elastomeric fibers include, but are not limited to, rubber filaments, mixed bicomponent filaments and elastoesters, rastol, and spandex.

"Spandex" is a made filament in which the filament-forming material is a long chain synthetic polymer composed of at least 85% by weight of segmented polyurethane.

"Elastester" is a filament made in which the fiber-forming material is a long chain synthetic polymer composed of at least 50% by weight aliphatic polyether and at least 35% by weight polyester.

“Mixed bicomponent filaments” are continuous filaments or fibers comprising two or more polymers attached to each other along the length of the filaments, wherein each polymer is of a different general class, such as elastomeric polyetheramide cores and lobes. Or it belongs to a polyamide sheath with a wing.

“Rastol” is a fiber of a crosslinked synthetic polymer with low but significant crystallinity, composed of at least 95% by weight ethylene and at least one other olefin unit. This fiber exhibits elasticity and substantially heat resistance.

"Polyester bicomponent filaments" are a pair of intimately attached to each other along the length of the fiber such that the fiber cross section is, for example, a parallel, eccentric sheath-core or other suitable cross section from which useful crimping can occur. It means a continuous filament comprising polyester. Fabrics made of such filaments, such as Elasterell-p, PTT/PET bicomponent fibers, have excellent recovery characteristics.

"Non-elastomeric elastic fiber" means an elastic filament containing no elastomeric fiber. However, the recoverable stretch of these yarns, such as textured PPT stretch filaments, textured PET stretch filaments, bicomponent stretch filament fibers, or PBT stretch filaments, should exceed 20% when tested by ASTM D6720 method. .

A “pre-covering elastic yarn” is one that is enclosed by, twisted with, or blended with a hard yarn prior to the core spinning process. Pre-covering elastic yarns comprising elastomeric fibers and hard yarns are also referred to herein as “pre-covering yarns” in the context of this specification. The hard yarn covering functions to protect the elastomeric fibers from abrasion during the fabric manufacturing process. Such abrasion can lead to breakage of the elastomeric fibers, resulting in process interruptions and undesirable fabric non-uniformities. Additionally, the covering facilitates the stabilization of the elastic behavior of the elastomeric fiber, so that the elongation of the pre-covering elastic yarn during the fabric manufacturing process can be controlled more uniformly than is possible with the raw elastomeric fiber. The pre-covering yarn can also increase the tensile modulus of the yarn and fabric, which facilitates improvement of fabric resilience and dimensional stability.

The pre-covering yarn comprises (a) an elastomeric fiber single coated with a hard yarn; (b) elastomeric fibers double coated with hard yarn; (c) elastomeric fibers continuously covered with staple fibers (ie, core spun or core-spinning), followed by twist processing during winding; (d) elastomeric and hard yarns mixed and entangled by air blasting; And (e) elastomeric fibers and hard yarns twisted together.

A "double elastic composite yarn" is a composite yarn comprising two sets of elastic core fibers with a single yarn, covered with a hard staple fiber sheath. The term “double elastic yarn” is used interchangeably throughout this specification.

The stretch fabrics of some embodiments include dual elastic core spun yarns in the weft direction. In some embodiments, particularly in the case of highly stretchable fabrics, fabrics with unexpectedly high resilience properties are achieved. This is achieved by the use of core spun yarns containing two different elastic fibers with different stretch properties. One of ordinary skill in the art will appreciate that where the weft stretch is desired, the fabric may include such core spun yarns with double elastic fibers in the weft direction.

As demonstrated in Fig. 1, the double elastic yarn 8 according to the invention will necessarily comprise two types of elastic filament cores: elastic core I (4 in Fig. 1) and elastic core II (6 in Fig. 1). . The elastic core filaments are surrounded, preferably along their entire length, by a fibrous sheath 2 composed of spun staple fibers.

One embodiment of a representative core spinning device 40 is shown in FIG. 2. Two separate fiber draft mechanisms 46 and 64 are installed in the machine. During the core spinning process, the elastic core filament I 48 and the elastic core filament II 60 are separately placed on the transfer rolls 46 and 64, and merged with the hard yarn to form a composite core spun yarn. The elastic core filaments from the tube 48 and the tube 60 are unwound in the direction of arrows 50 and 62 by the action of forward-driving feed rollers 46 and 64. Feed rollers 46 and 64 serve as cradles for tubes 48 and 60 and deliver elastic fiber yarns 52 and 66 at a predetermined speed.

The hard fibers or yarns 44 are unwound from the tube 54 to meet the elastic core filaments 52 and 66 at the location of the front roller 42. The combined elastic core filaments 52 and 66 and the hard fibers 44 are core spun together in a spinning apparatus 56.

The elastic core filament I 52 and the elastic core filament II 66 are stretched (drafted) before entering the front roller 42. The elastic filaments are stretched through the difference in speed between the feed rollers 46 or 64 and the front rollers 42. The transmission speed of the front roller 42 is higher than that of the feed rollers 46 and 64. The desired draft or stretch is provided by adjusting the speed of the feed rollers 46 and 64.

The stretchability is generally 1.01X to 5.0X times (1.01X to 5.0X) that of the unstretched fiber. Too low stretch will result in low quality yarns with grin-through and decentralized elastic filaments. Too high elasticity will lead to breakage of the elastic filaments and core voids.

Another embodiment of a representative core spinning device 40 is shown in FIG. 3. Elastic core I is a raw elastic filament 48, while elastic core II 12 is a pre-covering elastic yarn. The elastic core II from the tube 12 is unwound in the direction of the arrow 62 by the action of the forward-driving feed roller 64. The weighting roll 66 functions to maintain a stable contact between the elastic core II and the feed roller 64 to deliver the yarn 68 of the elastic core II at a predetermined speed. Other elements of FIG. 3 are as described for FIG. 2.

Another embodiment of a representative core spinning device 40 is shown in FIG. 4. Elastic core I is a raw elastic filament 48, while elastic core II 12 is a pre-covering elastic yarn. The elastic core II from the tube 12 is withdrawn from the end and then passed through a tension regulator and a guide bar. The tension regulator functions to stably maintain the tension of the yarn at a predetermined level. The stretchability of unprocessed elastic fibers is generally 1.01X to 5.0X times (1.01X to 5.0X) that of unstretched fibers. Other elements of FIG. 4 are as described for FIG. 2.

According to some embodiments of the method, two elastic fibers and hard fibers having different properties are covered together to form a composite yarn, wherein the two elastic fibers are in a different draft relative to their original length during the yarn covering process. It is newly built. The draft of the two types of elastic fibers may be selected from 1.01X times to 5.0X times draft. For two types of elastic core fibers having different denier or different number of filaments, the elasticity of the elastic core I and the elastic core II may be different from each other depending on the requirements of elastic fiber performance and fabric quality. In many cases, one core is more draped to provide high stretch performance, while another core is less stretched to provide a fabric with low shrinkage and high resilience.

In conventional fabrics, if heat setting is not used for "fixing" the spandex, the fabric can have high shrinkage, excessive fabric weight, and excessive elongation, which can lead to negative experiences for consumers. Excessive shrinkage during the fabric finishing process can lead to wrinkle marks on the fabric surface during processing and laundry at home. Wrinkles created in this way are usually very difficult to remove by ironing .

By using one of the elastic core fibers with a low draft, the high temperature heat setting step in the process can be avoided. This novel process can reduce thermal damage to certain fibers (ie, cotton) and thus improve the feel of the finished fabric. The fabric of some embodiments may be made without a heat setting step, where the fabric may be made of a garment. As a further advantage, heat-sensitive hard yarns can be used in novel processes for making shirting elastic fabrics, thus increasing the potential for a variety of improved products. In addition, the shortened process provides fabric manufacturers with productivity benefits.

Unexpectedly, it was found that core spun yarns with two different elastic core fibers have higher elasticity and resilience than core spun yarns made from a single elastic core filament with the same denier. For example, a core spun yarn with two cores of 30d/3 filament spandex and 40D/4 filament spandex has a greater recovery force than a core spun yarn made from a single core of 70D/5 filament yarn under the same draft. Therefore, a core spun yarn having a higher elasticity and a higher recovery power can be produced using the same content of spandex.

Two types of elastic fibers with different properties can be used and covered with a sheath of hard fibers to form a composite yarn, where the two types of elastic fibers can have different polymer compositions and different stress-strain behaviors. One example is the use of two types of spandex fibers with different heat setting efficiencies together in one core spun yarn, such as normal LYCRA® spandex fiber T162C and easy set Lycra® fiber T562B. The fabric can be heat set at a temperature higher than the Easy Set Lycra® fiber heat setting temperature, but lower than the normal Lycra® fiber heat setting temperature. Hence, the fabric achieves partial heat setting that provides acceptable fabric shrinkage with good stretch and stretch.

Another example is a core spun yarn containing an elastic core I having a high tensile modulus and an elastic core II having a low tensile modulus. The elastic core I provides a fabric with high resilience and low fabric elongation, while the elastic core II with a low elastic modulus provides a fabric with easy stretch, low shrinkage, and thus easy stretch, high retention and high dimensions. It results in a fabric with stability. Elastic fibers with different chemical compositions can also be combined with one type of core spun yarn, such as polyolefin elastic fiber rastol and spandex. Spandex fibers provide high resilience, while lastol fibers contribute to good heat resistance and reduced shrinkage performance.

The combination of the elastic core I and the elastic core II comprises an elastic raw fiber and an elastic raw fiber; Or elastic raw fibers and pre-covering elastic yarns; Or a pre-covering elastic yarn and a pre-covering elastic yarn. The raw elastic fiber may be from about 11 dtex to about 444 dtex (denier-about 10D to about 400D), for example 11 dtex to about 180 dtex (denier-10D to about 162D).

Pre-covering elastic yarns may be of various types, such as elastomeric fibers single coated with hard yarns; Elastomeric fibers double coated with hard yarn; Elastomeric fibers that are continuously covered with staple fibers (ie, core-spinning) and then twist processed during winding; Elastomer and hard yarn mixed and entangled by air jet; And elastomeric fibers and hard yarns twisted together. Preferred pre-covering elastic yarns are spandex air blast covering yarns with textured polyester and nylon filaments, such as 40D or 70D spandex air covered yarns with 50D to 150D polyester. The pre-covering elastic yarn is produced in a separate machine before the core spun yarn process.

The pre-covering elastic yarn may be present in any desired amount, for example in an amount from about 5 to about 35% by weight based on the total weight of the double elastic yarn. The linear density of the pre-covering yarn ranges from about 15 denier (16.5 dtex) to about 900 denier (990 dtex), for example about 30 denier to 300 denier (33 dtex to 330 dtex). When the ratio of yarn denier between the pre-covering yarn and the full double elastic yarn is less than 35%, the fabric does not exhibit substantial green-through. After the finishing process, the two elastic core fibers comprising the pre-covering yarn are not visible and non-contact.

The denier of the raw elastic fiber (before covering to form the pre-covering yarn) is from about 11 dtex to about 444 dtex (denier-about 10D to about 400D), for example 11 dtex to about 180 dtex (denier-10D to about 162D). During the pre-covering process, the elastic fibers are drafted to 1.1X to 6X of their original length. In pre-covering, the elastic fibers are pre-covered with one or more hard yarns having a hard yarn denier of 10 to 600 denier.

Another combination of elastic core fibers I and elastic core fibers II may be one set of elastic raw fibers and another set of non-elastomeric elastic fibers. The non-elastomeric elastic fiber may be a textured PET stretch filament, a textured PPT stretch filament, a bicomponent fiber, or a PBT stretch fiber. Surprisingly, it has been found that when a non-elastomeric elastic fiber having a recoverable stretch of more than 20% is used as one of the elastic core fibers, the performance of the core spun yarn and fabric changes significantly. The fabric has high elasticity and high resilience. The linear density of the non-elastomeric elastic fiber may range from about 15 denier (16.5 dtex) to about 450 denier (495 dtex), for example about 30 denier to 150 denier (33 dtex to 165 dtex). If the denier is too high, the fabric can exhibit substantial green-through.

The elastomeric fiber content in dual elastic core spun yarns is from about 0.1% to about 20%, such as from about 0.5% to about 15%, and from about 5% to about 10%, based on the weight of the yarn. The elastomeric fiber content in the fabric can be from about 0.01% to about 10% by weight, such as from about 0.5% to about 5%, based on the total weight of the fabric.

The staple sheath fibers of the double elastic yarn can be natural fibers such as cotton, wool or linen. They are also single-component staple artificial or synthetic fibers, poly(ethylene terephthalate) and poly(trimethylene terephthalate) fibers, polycaprolactam fibers, poly(hexamethylene adipamide) fibers, acrylic fibers, modacrylic, acetate fibers. , Rayon fibers, nylon and combinations thereof.

These double elastic yarns can be used in the manufacture of stretch fabrics, wherein plain weave, poplin, twill, oxford, dobby, satin, satin and combinations thereof Various weaving patterns can be applied, including. The fabrics of some embodiments may have an elongation of about 10% to about 45% in the warp or/and weft direction. The fabric may have a shrinkage of about 15% or less after washing with water. The stretch woven fabric can have a good cotton feel. Garments can be made from the fabrics described herein.

The warp may be the same or different from the weft. The fabric may exhibit only weft-stretch, or may exhibit stretch in both directions, where useful stretch and recovery properties are exhibited in both warp and weft yarns.

Air jet looms, rapier looms, projectile looms, water jet looms and shuttle looms can be used. Dyeing and finishing processes are important in the manufacture of satisfactory fabrics. The fabric can be finished in a continuous range process and a post dye spray process. Conventional equipment found in continuous finishing plants and post dyeing plants is usually suitable for processing. A typical sequence of finishing processes includes preparation, dyeing and finishing. In the preparation and dyeing process including wool, desizing, scouring, bleaching, polishing and dyeing, the general processing method of elastic woven fabrics is usually satisfactory.

Analysis method:

Yarn's recoverable elasticity

The recoverable elasticity of the elastic fibers used in the examples was measured as follows. Each yarn sample was formed into a total of 5000 +/- 5 denier (5550 dtex) skein using a skein reel with a tension of about 0.1 gpd (0.09 dN/tex). The skein was conditioned at 70° F. (+/- 2° F.) (21° +/- 1° C.) and 65% (+/- 2%) relative humidity for a minimum of 16 hours. The skein is suspended substantially vertically from the stand, a weight of 6 mg/den (5.4 mg/dtex) (e.g., 30 grams for a skein of 5550 dtex) is hung under the skein, and the weighted skein is of equilibrium length. Then, the length of the skein was measured to within 1 mm and recorded as "C _b ". A weight of 5.4 mg/dtex was left on the skein during the test period. Thereafter, a weight of 1030 grams (206 mg/d; 185.4 mg/dtex) was hung under the skein, and the length of the skein was measured to within 1 mm and recorded as “L _b ”.

After removing the weight of 1030 g, the skein was immersed in boiling water at 100° C. for 10 minutes, after which the skein was removed from the water and conditioned as described above for 16 hours. This step is designed by simulating a commercial fabric relaxation process, which is one method of generating stretchability of the fabric. The length of the skein was measured as above, and its length was recorded as “C _a ”. A weight of 1030 grams was again hung on the skein, and the length of the skein was measured as above and recorded as "L _a ". The recoverable stretch (%) "CC _a "of the yarn after relaxation was calculated according to the formula CC _a = 100 x (L _a -C _a )/L _a . The shrinkage of the yarn was calculated according to the formula Cs (%) = 100 X (L _b -L _a )/L _b .

Elongation of woven fabric (stretchability)

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

A first benchmark was set at 6.5 cm from the end of the sample across the width of each sample. The second benchmark was set at 50.0 cm from the first benchmark across the width of the sample. Using the extra fabric from the second benchmark to the other end of the sample, the metal pins were stitched to form an insertable loop. Thereafter, a notch was cut in the loop so that the weight could be attached to the metal pin.

The fabric sample was suspended vertically by clamping the non-loop end of the sample. A weight of 17.8 Newton (N) (4 LB) was attached to a metal pin through a suspended fabric loop, and the fabric sample was stretched by the weight. The sample was "moved" by allowing it to stretch and contract by the weight for 3 seconds, after which the force was manually removed by lifting the weight. This cycle was carried out 3 times. Thereafter, the weights were allowed to hang freely, and the fabric sample was stretched. When the fabric was loaded, the distance between the two benchmarks was measured in millimeters, and this distance was designated as ML. The original distance (i.e., non-stretching distance) between the benchmarks was designated as GL. Fabric elongation (%) for each individual sample was calculated as follows:

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

For the final result, the average of the three elongation results was calculated.

Woven fabric stretch (unrecovered stretch)

After stretching, the unstretched fabric will accurately restore its original length before stretching. However, typically, the stretch fabric will not fully recover and will become slightly longer after extended stretch. This slight increase in length is called "elongation".

The above fabric elongation test should be completed before the elongation test. Only the stretch direction of the fabric was tested. In the case of the two-way stretch fabric, both directions were tested. Three samples, each 55.0 cm x 6.0 cm, were cut from the fabric. These were different samples than those used in the elongation test. The 55.0 cm direction should correspond to the stretch direction. The sample was partially loosened to reduce the sample width to 5.0 cm. Samples were conditioned at the temperature and humidity of the elongation test. Two benchmarks were set up exactly 50 cm apart across the width of the sample.

Using the elongation% (E%) found from the elongation test, the length of the sample at 80% of this known elongation was calculated. It was calculated as follows:

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

Where L was the original length between benchmarks (i.e. 50.0 cm). Both ends of the sample were clamped and the sample was stretched until the length between the benchmarks was the calculated L + E (length). This stretch was maintained for 30 minutes, after which time the stretching force was released and the sample was suspended freely and relaxed. % Elongation after 60 minutes was measured as follows:

% Elongation = (L2 x 100)/L

Where L2 is the length increase between sample benchmarks after relaxation, and L is the original length between benchmarks. This% elongation was measured for each sample, and the average of the results was determined to determine the elongation value.

Shrinkage of woven fabric

After washing, the shrinkage of the fabric was measured. The fabric was first conditioned at the temperature and humidity of the elongation and elongation tests. Afterwards, two samples (60 cm x 60 cm) were cut from the fabric. Samples were taken at least 15 cm from the edge. A square with four sides of 40 cm x 40 cm was marked on the fabric sample.

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

Thereafter, the distance between the marks was measured to measure the shrinkage of the fabric sample in the warp and weft directions. The shrinkage C% after washing was calculated as follows:

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

Where L1 is the original distance between the marks (40 cm) and L2 is the distance after drying. The results for the samples were averaged and recorded for both weft and warp yarns. Negative shrinkage values reflect the expansion, which is possible in some cases due to the behavior of the hard yarn.

Fabric weight

Woven fabric samples were die-punched with a 10 cm diameter die. Each cut woven fabric sample was weighed in grams. Thereafter, the "fabric weight" was calculated in units of grams/m ² .

Example :

The following examples demonstrate the present invention and its ability to be used in the manufacture of various fabrics. Other different embodiments of the present invention are possible, and various details thereof may be changed in various obvious aspects without departing from the scope and spirit of the present invention. Accordingly, the examples are to be regarded as examples, not by way of limiting their properties.

In each of the following denim fabric examples, 100% pure cotton open end spun yarn or ring spun yarn was used as the warp. For the denim fabric, two count yarns were included: 7.0 Ne OE yarn and 8.5 Ne OE yarn with irregular arrangement pattern. The yarn was dyed indigo in the form of a rope before making it into a beam. After that, they were sized and a woven beam was made. The bottom weight fabric was a 20 Ne 100% pure cotton ring spun yarn with a warp. They were sized and woven beams were made.

Table 1 lists four examples of core spun yarns with yarns of the invention containing a traditional one elastic core filament and two sets of elastic cores.

A number of core spun yarns with double elastic core fibers were used as weft yarns. Various elastic core fibers were used in the core, including raw spandex, pre-covered polyester/Lycra® spandex fibers or pre-covered nylon/spandex yarns. Table 2 lists the materials and process methods used to make the core spun yarns of each example. Table 3 shows a summary of the detailed fabric structure and performance of each fabric. Lycra® spandex is manufactured by INVISTA, S.W. of Wichita, Kansas, USA. a. egg. It is commercially available from Invista, s. a. r. L.). For example, in a column titled Spandex, 40D means 40 denier; 3.5X means the draft of Lycra® (mechanical draft) imparted by the core spinning machine. In the column titled'Rigid Sheath Yarn', 20's is the linear density of the spun yarn as measured by the English Cotton Count System. The remaining items in Tables 1 and 2 are clearly labeled.

Using the core spun yarn of each example in Table 2, a stretch woven fabric was subsequently produced. Table 3 summarizes the yarns used in the fabric, the weave pattern, and the quality characteristics of the fabric. Some additional explanations for each example are provided below. Unless otherwise stated, the fabric was woven on a Donier air-jet or rapier loom. The loom speed was 500 picks/minute. The width of the fabric was about 76 inches and about 72 inches, respectively, in the loom and greige condition. The loom had a double weave beam capability.

In the examples each raw fabric was finished by a jiggle dyeing machine. Each woven fabric was pre-refined with 3.0% by weight of Lubit®64 (Sybron Inc.) at 49° C. for 10 minutes. Thereafter, 6.0% by weight of Synthazyme® (Dooley Chemicals. LLC Inc.) and 2.0% by weight of Merpol® LFH (E. I. DuPont Campa) Ni (EI DuPont Co.)) for 30 minutes at 71° C., then 30 at 82° C. with 3.0% by weight of Rubit® 64, 0.5% by weight of Merpol® LFH and 0.5% by weight of trisodium phosphate. Refined for minutes. After fabric finishing, it was dried at 160° C. for 1 minute on a tente frame.

<Table 1>

<Table 2>

<Table 3>

Example Yarn A: Typical core spun yarn with one elastic core fiber

This is not the yarn of the present invention. This core spun yarn is a type of 40d Lycra® spandex fiber with 16 Ne, covered with a cotton sheath. The draft of Lycra® fiber is 3.5X during the covering process. Cotton twist level TM is 18 twists per inch. This yarn has a recoverable stretch of 17.71% after boiling and refining.

Example Yarn B: Core spun yarn with two types of elastic core fibers

The core spun yarn is two sets of Lycra® spandex fibers with 16 Ne, covered with a cotton sheath. The elastic core I fiber is 20D T162B, and the elastic core II fiber is also 20D T162B. The total denier of the elastic fiber is 40 denier. The draft of Lycra® fiber is 3.5X during the covering process. Cotton twist level TM is 18 twisters per inch. Thus, this core spun yarn has the same structure as Example Yarn A, including yarn count, Lycra® fiber denier and yarn twist level, except that it has 2 sets of elastic core filaments instead of 1 set of core spun yarns. Have. The recoverable stretch of this yarn is 20.63%, which is 2.92 percentage units higher than the yarn of Sample A. This means that yarns with two sets of filament cores have a higher recoverable stretch than yarns with one set of filament cores under the same spandex content. In this way, the yarns of the present invention can provide high elasticity and high resilience using the same amount of elastic fibers for the fabric.

Example Yarn C: Typical core spun yarn with one elastic core fiber

This is not the yarn of the present invention. The core spun yarn is one kind of 70d Lycra® spandex fiber with 16 Ne, covered with a cotton sheath. The draft of Lycra® fiber is 3.8X during the covering process. Cotton twist level TM is 18 twisters per inch. This yarn has a recoverable stretch of 38.71% and a shrinkage of 2.28% after boiling refining.

Example Yarn D: Core spun yarn with two types of elastic core fibers

The core spun yarn is two sets of Lycra® spandex fibers with 16 Ne, covered with a cotton sheath. The elastic core I fiber is 30D T162B, and the elastic core II fiber is 40D T162B. The total denier of the elastic fiber is 70 denier. The draft of both Lycra® fibers is 3.8X during the covering process. Cotton twist level TM is 18 twisters per inch. Thus, this core spun yarn has the same structure as Example yarn C, except that it has two sets of elastic core filaments instead of one set of core spun yarns. The recoverable stretch of this yarn is 40.88%, which is 2.17 percent higher than yarn sample C. This shows that yarns with two sets of filament cores have higher recoverable stretch properties than yarns with one set of filament cores under the same spandex content. In this way, the yarn of the present invention can provide high elasticity and high resilience using the same amount of elastic fibers for the fabric.

Example 1: Typical stretch woven bottom weight fabric

This example is a comparative example that does not follow the present invention. The warp is a ring spun yarn of number 40/2 Ne. The weft is a 20 Ne cotton yarn with 40D Lycra® core spun yarn. The Lycra® draft is 3.5X. This weft is a typical stretch yarn used in typical stretch woven khaki fabrics. The loom speed was 500 picks/minute at a pick level of 56 picks/inch. Table 3 summarizes the test results. The test results show that after finishing, this fabric has weight (8.95 g/m ² ), stretch (37.6%), width (50.5 inches), weft wash shrinkage (0.91%) and fabric elongation (8.7%). The data suggests that this combination of stretchy yarns and fabric composition results in high fabric elongation.

Example 2: Stretch fabric with double elastic fibers

This sample has the same fabric structure as Example 1. The only difference is the use of a double elastic core fiber: a 20s weft containing 3.5X draft 40D Lycra® fibers and 1.8X draft 40D Lycra® fibers. The warp is 40/2 Ne ring spun cotton yarn. The loom speed was 500 picks/minute at 56 picks/inch. Table 3 summarizes the test results. This clearly shows that this sample has similar stretch, but lower fabric stretch level (6.4%). Thus, by using two different drafts of elastic core fibers in the same yarn, the covering yarn and fabric can achieve different characteristics. For example, a high draft of elastic core I fibers provides a fabric with high elasticity, whereas a low draft of elastic core II fibers results in a fabric having low elongation, high recovery, but no increase in fabric shrinkage. Provided. In this way, fabrics with high elasticity, high recovery and low shrinkage can be produced.

Example 3: Stretch fabric containing double elastic fibers

This sample has the same fabric structure as Example 1. The only difference is the use of core spun yarn on the weft: 40D T162B Lycra® fiber from 3.5X draft and 40d Easy Set Lycra® fiber from 3.5X draft. The warp is 20 Ne 100% pure cotton ring spun yarn. A 3/1 twill weave pattern was applied. The finished fabric had a weight (9.19 g/m ² ), 38.4% stretch in the weft direction and 7.9% stretch. This clearly shows that the Easy Set Lycra® fibers of Elastic Core II reduce the fabric stretchability from 8.7% to 7.9% in Example 1, while maintaining the fabric stretch level.

Easy Set Lycra® fiber can be heat set at about 170°C, which is about 20°C lower than that of T162B Lycra® fiber. Thus, when the fabric was heat set at a temperature of 170°C to 190°C, the fabric was partially heat set. Only Easy Set Lycra® fibers were fixed and T162B was not. In this way, the fabric maintained good stretch and recovery, while keeping the shrinkage below a certain level.

Example 4: Stretch fabric with spandex and elastic polyolefin fibers

The warp is an open end yarn with a mixture of 7.0 Ne and 8.4 Ne counts. The warp was dyed indigo before making it into a beam. The weft is a 16 Ne core spun yarn with 40D T162B Lycra® spandex and 40D elastic polyolefin fibers. Lycra® fibers and elastic polyester fibers were drafted 3.5X during the covering process. Table 3 lists the fabric properties. Fabrics made from these yarns showed good cotton feel, good stretch (47.8%) and good recovery (6.5% elongation). All test results suggest that the combination of spandex and elastic polyolefin filaments can result in good fabric stretch and stretch. The fabric did not show green-through. The elastic filaments were not visible on the fabric surface and on the fabric back side.

Compared with spandex, elastic polyolefin fibers or rastol fibers have low recovery power, but have excellent heat resistance, good chemical resistance, low fabric shrinkage and good cotton feel. Fabrics containing both spandex and elastic polyolefins could provide good stretch and good recovery, with good heat resistance, low shrinkage and good chemical resistance, such as chlorine resistance in swimming pool and denim bleaching processes.

Example 5: Stretch fabric containing spandex and pre-covering elastic yarn

This sample has the same fabric structure as Example 1. The difference is a core spun yarn in the weft direction, containing one raw 40D Lycra® fiber and one pre-covered elastic yarn (40D/34f nylon/40D Lycra® air covered yarn) in the core of the yarn. The draft of the raw 40D Lycra® fiber is 1.8X, and the draft of Lycra® fiber in the pre-covering elastic yarn is 3.2X. This fabric used the same warp and structure as in Example 1. In addition, the weaving and finishing processes were also the same as in Example 1. Table 3 summarizes the test results. It can be seen that this sample has good stretchability (35.9%), good weft direction washing shrinkage (0.65%) and good fabric elongation (5.3%). The fabric look and feel were excellent. After addition of the pre-covering elastic yarn (40D/34f nylon/40D Lycra® fiber AJY yarn), the fabric stretchability was significantly reduced.

Example 6: Stretch Fabric Containing Spandex and Pre-Covering Elastic Yarn

This sample has the same fabric structure as Example 5. The only difference is the draft of 40D raw Lycra® fiber during the covering process. The draft of the raw Lycra® fiber was 3.5X, which in Example 5 was 1.8X. The fabric weight was 8.96 OZ/yd ² and the weft elongation was 37.8%. The fabric had very low elongation (5.9%) in the weft direction. This sample again confirms that the addition of an additional elastic composite yarn can produce a high stretch performance fabric with low stretch. The double elastic yarn made the fabric stretch from 8.7% to 5.9% in Example 1. Compared to Example 5, an increase in draft also resulted in increased weight and elasticity.

Example 7: spandex And stretch denim containing pre-covering elastic yarn.

This embodiment has the same warp and the same fabric structure as Example 4. The warp is an open end yarn with a mixture of 7.0 Ne and 8.4 Ne counts. The warp was dyed indigo before making it into a beam. The weft is a 16 Ne core spun yarn with 40D Lycra® spandex and 50D/24f polyester 40D Lycra® fiber air blowing covering yarn. Lycra® Draft is 3.5X and 1.8X in raw and composite cores. This sample is the fabric of the present invention. The loom speed was 500 picks/minute at a pick level of 44 picks/inch. Table 3 summarizes the test results. The test results show that after washing with water, this fabric has a weight (12.80 OZ/Y ² ), 35.3% weft stretch and 3.5% stretch of weft.

Example 8: spandex And stretch denim containing pre-covering elastic yarn.

This example had the same warp and same fabric structure as Example 7 except for the Lycra® fiber draft of the pre-covering elastic yarn (1.8X draft in Example 7, whereas 2.6X draft in Example 8). Have. Table 3 summarizes the test results. It is clear that this sample has good stretchability (40.4% weft) compared to sample 7.

Example 9: Stretch fabric with spandex and PBT stretch fibers

This example has the same warp and same fabric structure as Examples 7 and 8, except that 50D/26f PBT stretch fiber is used as the elastic core II fiber. This raw 50D/26f PBT fiber had a recoverable stretch of 40.23% and a shrinkage of 3.44% when tested by the ASTM D6720 method. Elastic Core I Lycra® fibers were draped 3.5X during the covering process. Table 3 lists the fabric properties.

Fabrics made from these yarns showed good cotton feel, good stretch (40.7%) and good recovery (6.0% elongation). All test results suggest that the combination of spandex and non-elastomeric stretch filaments can result in good fabric stretch and stretch. The fabric did not show green-through; Elastic filaments were not visible on both the fabric surface and the fabric back side.

Claims (21)

An article comprising a core spun yarn, wherein the core spun yarn
a) sheath of hard fibers;
b) elastic core fibers I comprising spandex providing elasticity to the article; And
c) an elastic core fiber II that provides resilience to the article and is separate from the elastic core fiber I, comprising spandex.
Wherein the elastic core fiber I and the elastic core fiber II have different elastic properties, and the core spun yarns exhibit higher elasticity and resilience than single core spun yarns having the same spandex content. The article of claim 1, wherein the elastic core fiber I and the elastic core fiber II have different deniers or different filaments. The article of claim 1 wherein the elastic core fiber I and the elastic core fiber II have different drafts. The article of claim 1, wherein the elastic core fiber I and the elastic core fiber II have different polymer compositions. The article of claim 1 wherein the at least one elastic core fiber comprises elastomeric fibers having a denier of 10 denier to 450 denier. delete delete delete The article of claim 1, wherein the at least one set of elastic core yarns is a pre-covering elastic yarn having a denier of 15 denier to 300 denier. 10. The article of claim 9, wherein the pre-covering elastic yarn comprises a covering selected from the group of air covered yarns, single coated yarns, double coated yarns, and combinations thereof. 10. The article of claim 9, wherein the pre-covering elastic yarn is a polyester and spandex air covered yarn. The article of claim 1 wherein the at least one elastic core fiber comprises a non-elastomeric elastic fiber having a denier of 15 to 450 denier. The article of claim 12, wherein the non-elastomeric elastic yarn is selected from the group of filaments having a recoverable stretch of the yarn greater than 20% when tested by the ASTM D6720-07 method. 14. The article of claim 13, wherein the non-elastomeric elastic yarn comprises at least one fiber selected from the group consisting of polyester, nylon, PTT fiber, PBT fiber, bicomponent fiber, and combinations thereof. The article of claim 1, wherein the sheath of the hard fiber is selected from the group consisting of wool, linen, silk, polyester, nylon, olefin, cotton, and combinations thereof. An article comprising a woven fabric having warp and weft, wherein at least one of warp and weft
a) sheath of hard fibers;
b) an elastic core fiber I comprising spandex providing elasticity to the fabric; And
c) elastic core fiber II, which provides resilience to the fabric and is separate from elastic core fiber I, comprising spandex.
A core spun yarn comprising a, wherein the elastic core fiber I and the elastic core fiber II have different elastic properties, and the core spun yarn exhibits higher elasticity and resilience than a single core spun yarn having the same spandex content. , Goods. 17. The article of claim 16, wherein the fabric has 10-45% stretch in the weft direction. 17. The article of claim 16, wherein the fabric comprises a garment. A method of making an article comprising a woven fabric having warp and weft, wherein either warp or weft or both warp and weft
a) sheath of hard fibers;
b) an elastic core fiber I comprising spandex providing elasticity to the fabric; And
c) elastic core fiber II, which provides resilience to the fabric and is separate from elastic core fiber I, comprising spandex.
Having a core spun yarn comprising, wherein the elastic core fiber I and the elastic core fiber II have different elastic properties, and the core spun yarn exhibits higher elasticity and resilience than a single core spun yarn having the same spandex content, Way. It is an elastic fabric comprising a core spun yarn, the core spun yarn
a) sheath of hard fibers;
b) an elastic core fiber I comprising spandex providing elasticity to the fabric; And
c) elastic core fiber II, which provides resilience to the fabric and is separate from elastic core fiber I, comprising spandex.
Wherein the elastic core fiber I and the elastic core fiber II have different elastic properties, and the core spun yarn exhibits higher elasticity and resilience than a single core spun yarn having the same spandex content. 21. The stretch fabric of claim 20, wherein the fabric is a woven or warp or circular knitted fabric.

Images