WO2021083527A1

WO2021083527A1 - Elastic yarn, knitted textile material and sock made with the elastic yarn

Info

Publication number: WO2021083527A1
Application number: PCT/EP2019/079889
Authority: WO
Inventors: Hakan Konukoglu; Gökhan Aydin
Original assignee: Sanko Tekstil Isletmeleri Sanayi Ve Ticaret Anonim Sirketi
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2021-05-06
Also published as: TW202118914A; TWI755682B; JP2022554311A; JP7373660B2; CA3158753A1; EP4051833A1; US20240167200A1

Abstract

An elastic yarn is provided comprising at least one elastic filament and at least one further filament, which form a core of the yarn. As different regions of a garment, e.g. socks, need to have different properties in view of recovery, comfort and robustness, and as it is important that the respective articles are easy to produce in the elastic yarn, the elastic filament has a draft between 0.2 and 15.0, and the further filament has a draft of between 0.2 and 5.0.

Description

ELASTIC YARN, KNITTED TEXTILE MATERIAL AND SOCK MADE WITH THE ELASTIC YARN

The present invention is related to an elastic yarn.

Such an elastic yarn is used in knitting textile materials. Such textile materials can be used in the production of garment and especially underwear and socks.

For example, a stretch circular knitted fabric is described in WO 2018/081057 A1. Said document describes that most available stretch circular knit fabrics on the market are made with a single type of elastic fiber and rigid fibers. Such fabrics are widely known as comfort fabrics as they can more easily be formed and stretched during wear. The wearing comfort of garments made from these knit fabrics comes from the stitch rearrangement and elastic fiber extension. However, recovery by knit stitch rearrangement and single elastic fiber is generally incomplete because the yarn does not provide adequate recovery force to rearrange the stretched knit stitches. As a consequence, single elastic knit fabrics may experience permanent deformation or bagging in certain garment areas, such as elbows in shirt sleeves or particular regions of socks where more stretching occurs. In order to improve this, WO 2018/081857 provides a knitted fabric having the configuration shown in figure 1 .

In the circular knit fabric, two sets of elastic yarns, namely the first set being elastomeric yarn 12 and the second set being polyester bi-component filament 18, is used. The elastic yarns 12, and 18 are used together with a hard yarn 14 in the knitting.

A drawback of this configuration is that three distinct yarns are used which are knitted.

US 6158253 disclosed high stretchable seamless and wrinkle free foot socks so that all focal pressure points which must otherwise be created by the socks are eliminated. It is thus provided a yarn having an elastomeric core filament inside a cover layer made of non-elastic fibers.

Different knitting patterns / stitch geometries are used in different regions of the socks. This is shown schematically in figure 2, which is based on figure 1 of the prior art US 158253. Herein, the respective sections 24, 26, and 18 have a different knitting pattern respectively stitch geometry.

A further document which discloses the utilization of different knitting patterns in socks is WO 03/056084 A1 .

In view of the aforementioned disclosure, there is still room for improvement. In particular, different regions of a garment, e.g. socks, need to have different properties in view of recovery, comfort and robustness. Further, it is important that the respective articles are easy to produce.

In view of this, there is provided an elastic yarn having the features defined in claim 1 .

The elastic yarn has at least one elastic filament and at least one further filament, which form a core of the yarn. The present inventors found for the first time, that when a draft of the elastic filament is between 0.2 and 15.0, and that further additionally, if the further filament has a draft of between 0.2 and 5.0, improved properties of the yarn and the final garment in terms of recovery, comfort and robustness can be obtained.

Drawing or so-called drafting in yarn manufacturing is a process of extenuating the loose assemblage of fibers called sliver by passing it through a series of rollers, thus straightening the individual fibers and making them more parallel. Each pair of rollers spins faster than the previous one. Drawing reduces a soft mass of fiber to a firm uniform strand of usable size. In the production of man-made fibers, drawing is a stretching process applied to fibers in the plastic state, increasing orientation and reducing size. In the present disclosure the strand obtained after drafting is named filament. The final yarn can contain one or more of such filaments as the core.

The numerical value of the draft is a dimensionless value.

The at least one elastic filament and the at least one further filament can be twisted together to form the core of the yarn.

According to a further development, the elastic filament can have a draft between 0.2 and 12.0, and in particular between 1 .0 and 3.0. Further upper and/or lower draft limits of the elastic filament are 0.8, 1 .0, 1 .5, 2.5, 4.0, 6.5, 8.5, 9.0 . Additionally or alternatively, the further filament can have a draft between 1 and 1 .3. Further upper and/or lower draft limits of the further filament are 1 .5, 2.5, 4.0. The respective upper and lower limits described for the drafts of the elastic filaments and the further filaments can be combined with each other, such that the elastic filament a lower limit of the draft is 2.5 and an upper limit is 3. For the further filament e.g. a lower limit is 1 .3 and an upper limit is 2. When the aforementioned particular ranges of drafts are used, a further improved effect in view of recovery, comfort and robustness can be achieved. E.g. for the elastic filament the draft is generally increased as the tension acting on the elastic filament during drafting is increased.

It is beneficial that the further filament has a lower draft than the elastic filament. According to a further development, the filament can be twisted together such that the core, can have a twist between 300 and 3500. Further limits can be 400, 450, 500, 550, 650, 700, 800, 900, 1100. Each of the respective values can be used as lower and upper limit in the range of twists. Alternatiively or additionally the core can have a cover layer, which is e.g. made of staple fibers. The complete arrangement of the core and the cover layer forms the yarn which may have a twist which has the aforementioned values.

The twist is the spiral arrangement of the filaments and/ or core and/or complete yarn around the axis of the yarn. The twist binds the filaments and/or core and/or yarn together and also contributes to the strength of the yarn. The amount of twist inserted in the yarn defines the strength and appearance of the yarn. The number of twists is referred to as turns per meter That means a twist of 400 corresponds to 400 twist per meter (TPM).The twist correspond to the spiral arrangement of the filament constituting the core, such that the core is twisted. That means the core can have the aforementioned twist values. The core can be provided within a cladding layer of staple fibers as it is described below.

In practice the twist of the yarn is commonly described using three main parameters a) the twist direction, b) the twist factor or twist multiplier and c) the twist level (turns/unit length). The aforementioned value between 300 and 3500 corresponds to the twist level .

The twist factor (in the following named as a value relating twist level to yarn count. The derivation shows that if two yarns have the same twist factor, they will have the same surface twist angle, regardless of count. Since surface twist angle is the main factor determining yarn character, then twist factor can be used to define the character of a yarn.

The inventors found that a lower twist, e.g. a lower twist of the yarn compared to the conventional known yarns provides a further improved effect in view of recovery, comfort and spirality of the garment e.g. the socks.

According to a further development, the further filament is an inelastic filament. Therefore, the elastic yarn has a core with at least one elastic filament and at least one inelastic filament, which are twisted together. The combination of the elastic and inelastic filament provides a further improvement of the elastic yarn.

The further filament can be made from a material chosen from the group of Polyester, Polyamid, Polyether Sulfones , Polybutylene Terephthalate (PBT), Partial Oriented Yarn (POY), and/or a mixture thereof. It is also possible to use as further filament any natural or synthetic filament. Instead of the further filament one can also use a spun yarn. This can be a further invention and the term further filament in the claims can be changed to spun yarn as additional alternative. The afore mentioned drafts for the further filament can be used for the spun yarn as well. A spun yarn can be a textile yarn spun from staple-length fiber.

The elastic filament may be filament having any elasticity, for example an elastane yarn. The used elastane filaments may be filaments sold under the trademark from the respective company (e.g. company is given in the following in brackets): LYCRA (DuPont), SPANDEX (Monsanto), CREORA (Hyosung) and filaments from HUAFON which are in the following called HUAFON filaments, the material of the HAUAFON filaments may be sold under the trademark QIANXI.

Elasticity is the ability to deform reversibly under stress. The elasticity may have an elastic modulus, the Young’s modulus (in GPa) of 0.01 to 5, more preferably 0.01 to 0.5 in particular, 0.01 to 0.1 . Alternatively or additionally, the elongation may be in the range of 3 to 22%. Wherein the % value defines the relative elongation from a relaxed state to a state where the yarn is expanded to the maximum where a reversible contraction can still occur. Further preferred elongations are: 4%, 6%, 8%, 10%, 13%, 15%, 18%, 20%. The aforementioned values may each separately serve as lower or upper limits.

According to a further embodiment, the core, which is comprised of the twisted filaments, is covered by a cover layer to form the yarn. The cover layer comprises staple fibers. The staple fibers may comprise at least one or a mixture of fibers from the group of: natural, recycled and/or synthetic fibers and/or fibers made of the following materials: cotton, viscose, polyester, wool, linen, alpaca, vicuna, angora, cashmere, kapok, manila, flax, hemp, ramie, hessian, sisal, coir, asbestos, glass, azlon, acetate, triacetate, acrylic, aramid, polyamide, olefin. The respective fibers made of the aforementioned material may be used as a single material fiber mixture or a composition of any one of the aforementioned different material fibers in one of different lengths. Due to this cover layer, the yarn feels comfortable and natural while it is combined with elastic properties.

Further embodiments of the yarn are that the core comprises more than three filaments and less than six filaments. Examples of the composition of the core are two or three elastic filaments and one or two or three inelastic filaments. Those filaments are all twisted together.

When more than one elastic filament is provided in the core, each elastic filament can have the aforementioned draft. The drafts of the used elastic filaments in the core may be the same for each filament or each filament may have a different draft. When more than one further filament is provided in the core, each of the further filaments can have the aforementioned draft. The drafts of the used further filaments in the core may be the same for each of the further filament or each of the further filament may have a different draft.

According to a further aspect of the invention, there is provided a knitted textile material. This textile material comprises the inventive yarn. The yarn is knitted by circular knitting or other knitting techniques, which are executed by a machine. The knitted textile material comprises regions having different knitting patterns e.g. pattern with different stitching geometries. However, the same yarn is used as the only material in the respective different knitting pattern.

The different knitting pattern/stitching geometries might have different properties concerning stretch compression or the like. The respective knitted textile material with the different knitting pattern is entirely made from the same yarn material which is the inventive yarn material. Only due to the different knitting pattern, the respective properties in certain regions can be tuned.

According to a further aspect, there is provided a sock, which is made entirely, or at least in the region of the toes, the foot, the heel and the leg, from a single type of yarn, wherein the yarn is the aforementioned inventive yarn. This sock may have different knitting patterns at the foot area, the toe area, the heel area or the leg area. The respective different areas are knitted by the same yarn material.

Only due to the different knitting pattern or stitching geometries, the respective properties in the respective regions can be tuned.

When the inventive yarn is used in the production of a knitted textile material, the spirality of the material is reduced. Spirality is a common problem in weft knitted fabric. It is the de- twisting tendency of yarn in the fabric. Spirality arises from twist stress in the constituent yams of plain fabric, causing all loops to distort and throwing the fabric wales and courses into an angular relationship other than 90 degree. There are various causes of fabric spirality and they are divided into four main categories: yarn causes, knit causes, fiber causes, and finishing causes.

Further preferred embodiments will be apparent from the explanations in the subsequent section in combination with table 1 .

Figure 1 shows a known knitted fabric, which is disclosed in WO 2018/081057.

Figure 2 shows a sock with different knitting patterns, which is disclosed in US 6158253.

Figures 3 to 6 show different knitting patterns / stitching geometries which can also be made with the inventive yarn. Explanations concerning terms

The following explanations shall not be interpret in a delimited way. This explanations help to interpret the used wording.

Knitting

Knitting is a method by which yarn is manipulated to create a textile of fibers. Knitting creates multiple loops of yarn called stitches. Knitted fabric consists of a number of consecutive rows of loops. Each row progresses a newly created loop as pulled through one or more loops from the prior row, placed on the gaining needle and the loops from the prior row are then pulled off the other needle. Different types of yarns, needle sizes, and stitch types may be used to achieve knitted fabrics of different properties. The term circular knitting is used to mean a form of weft knitting in which the knitted needles are organized into a circular knitting bed. Generally, a cylinder rotates an interacts with a cam to move the needle through a support for knitting action. The yarn to be knitted is fed from a package to a carry plate that directs the yarn strength to the needles. The circular knit fabric emerges from the knitting needles in a tubular form from the center of the cylinder.

Figures 3 to 6 show different knitting patterns/ stitching geometries which can also be made with the inventive yarn

Yarn

Yarn is understood as a long continuous length of interlocked fibers suitable for use in the production of textiles including crocheting, knitting, weaving, embroidering, and rope making.

Twist

The twist is the spiral arrangement of the filaments and/ or core and/or complete yarn around the axis of the yarn. The twist binds the filaments and/ or core and/or complete yarn together and also contributes to the strength of the yarn. The amount of twist inserted in the yarn defines the strength and appearance of the yarn. The number of twists is referred to as turns per meter That means a twist of 400 corresponds to 400 twist per meter (TPM). The twist correspond to the spiral arrangement of the filament constituting the core, such that the core is twisted. That means the core can have the aforementioned twist values. The core can be provided within a cladding layer of staple fibers as it is described below. In practice, the twist of the yarn is commonly described using three main parameters a) the twist direction, b) the twist factor or twist multiplier and c) the twist level (turns/unit length). The aforementioned value between 300 and 3500 corresponds to the twist level.

Draft

The numerical value of the draft is a dimensionless value. Yarn count

The yarn count is a numerical expression which defines its fineness or coarseness. It also expresses whether the yarn is thick or thin. A definition is given by the textile institute - “Count is a number which indicates the mass per unit length or the length per unit mass of yarn.” There are various yarn counting ways used globally/ historically, such as direct counting in Tex or Denier, when relating a fixed length of yarn to its resulting weight. Alternatively, the yarn count is defined indirectly by using fixed weight of fiber relating to the varying length. In the following two yarn count are used, one in Denier and one in Ne. The direct yarn count Denier [den] is defined as grams of fiber for the length of 9,000 meters, while the indirect yarn count Ne relates to the number of 840 yards of yarn in 1 pound of fiber.

Spirality

Spirality is a common problem in weft knitted fabric. It is the de- twisting tendency of yarn in the fabric. Spirality arises from twist stress in the constituent yams of plain fabric, causing all loops to distort and throwing the fabric wales and courses into an angular relationship other than 90 degree. There are various causes of fabric spirality and they are divided into four main categories: yarn causes, knit causes, fiber causes, and finishing causes. Experiments

In table 1 below, the experimental results with the inventive yarn is compared with conventional yarn which is used for knitting socks.

Lines 1 to 18 show different inventive examples. In lines 19 to 21 , properties of well -known yarn are summarized.

The column “yarn code”, assigns a respective in-house-code to each yarn.

The yarn count is a numerical expression which defines its fineness or coarseness. It also expresses whether the yarn is thick or thin. Two yarn counts are used in the table, one in Denier and one in Ne. The direct yarn count Denier [den] is defined as grams of fiber for the length of 9,000 meters, while the indirect yarn count Ne relates to the number of 840 yards of yarn in 1 pound of fiber.

In the above table, the count is given in Denier (TD) for the columns “elastane count” and “filament count”, while it is given in Ne (Ne) for the column titled “Yarn count”. The inventive yarns have yarn counts in Ne between 15 and 20. In particular, it is preferred that the yarn count is between 15 and 18 Ne (e.g. column with the header “Yarn Count NE”). The respective prior art yarns, which are used for comparison, have a yarn count of 20 Ne.

In the column titled “elastane type”, there is provided the information which type of elastane filament is used as elastic filament. In the examples 1 to 15 as elastane filament, so-called HUAFON filament is used. HUAFON is the supplier of the yarn. An example of this yarn may be the yarn sold under the trademark QIANXI.

The used elastane filaments may be filaments sold under the trademark (the term in brackets denotes the supplier): LYCRA (DuPont), SPANDEX (Monsanto), CREORA (Hyosung), and filaments from HUAFON which are in the following called HUAFON filaments, the material of the HAUAFON filaments may be sold under the trademark QIANXI.

The count (in Denier) of the elastic filament is given in the column titled “elastane count”. The inventive yarn uses an elastic filament having a count of 40 or respectively 20 (Example 8). In particular, a range of 10 to 60 is preferred. Further values are 30, 40, 50. Said values can be an upper or lower border in a preferred range of counts.

The respective prior art examples 21 and 22 are thicker and have a count between 70 and 105.

The elastane draft (e.g. column with the header “elastane draft”) in the example is between 1.5 and 3. It has been observed that the draft of the elastic filament is for an improved effect between 1 and 3 and preferably between 1 .5 and 2.5. Also tests have been made that show that the elastic filament can have a draft between 0.2 and 15.0, and the further filament can have a draft of between 0.2 and 5.0. Also said values provide the improved properties.

Conversely thereto, for the prior art filaments, the draft of the elastic filament is higher, namely it is in the region of higher than 3.5.

As further filaments in the present invention there are used in examples 1 to 14, FDI typed PES or respective texturized PES.

In the examples 15 to 18, instead of using a single elastane filament and a single further filament, a so- called GIPE yarn is used. A GIPE yarn has a core of an elastane and a further filament, in particular a Polyether Sulfone filament. However, during the production of the GIPE both filaments come together by air twisting. The elastane filament of the GIPE has a count of 70 Denier while the respective further filament (here the PES filament) has a count of 40 Denier (see column “filament count”). The respective term in brackets in the column “filament count” denotes the draft of the respective elastane filament in the GIPE yarn. This means the elastane filament in the GIPE has a count of 70 Denier a draft of 2.5.The PES filament in the GIPE has a draft of 1 .4 (see column “filament draft”).

Thus, in all inventive examples the further filament, which is in this case an inelastic filament, has a filament draft of 1.14. In accordance with the present invention, the further filament has a draft of between 1 and 2, and preferably between 1 .1 and 1 .4. Also tests have been made that show that the elastic filament can have a draft between 0.2 and 15.0, and the further filament can have a draft of between 0.2 and 5.0. Also said values provide the improved properties.

The so-called alfa of the yarn denotes the respective twist factor. This twist factor is for the inventive yarns between 2.8 and 3.5. Further preferred values are 3.0; 3.2. These values can be used independently as upper or lower limits.

The conventional yarns (Examples 21 to 23) have an alfa of 4.3.

The column “twists” shows the yarn twists which are compared with the twists of the prior known yarns (Examples 19 to 21). The core of the inventive yarn has in the examples a twist between 400 to 700 twist per meter. Conversely thereto, the respective conventional yarn has a twist of 757. Thus, the twist of the inventive yarn is lower as in the conventional yarn. Thus, when the inventive yarn is used in the production of a knitted textile material the spirality of the material is reduced.

The twisted filaments, which form the core, can have a twist between 300 and 1100. Further limits can be 400, 450, 500, 550, 650, 700, 800, 900. Each of the respective values can be used as lower and upper limit in the range of twists.

In the last column of the above table, information is contained concerning the diameter of the respective manufactured socks in inches.

The aforementioned table shows that when an elastic yarn, having an elastic filament with a draft between 1 .0 and 3.0 and a further filament with a draft of between 1 .0 and 2.0 is used, the respective properties of the yarn can be improved. Also tests have been made that show that the elastic filament can have a draft between 0.2 and 15.0, and the further filament can have a draft of between 0.2 and 5.0. Also said values provide the improved properties.

In particular, socks can be manufactured made of one single yarn type, wherein the different zones of the socks have different knitting patterns. Alternatively, there can also be made socks which comprises the inventive yarn, wherein one or more further yarns are also used for the same sock (e.g. in different zones).

Although the Examples in the table show a delimited draft range, the plurality of further Experiments which were made by the Applicant show that for the invention it is enough that a draft of the elastic filament is between 0.2 and 15.0, and that further additionally the further filament has a draft of between 0.2 and 5.0. Also in this broader range of values, the improved properties of the yarn and the final garment in terms of recovery, comfort and robustness can be obtained.

According to a further development, the elastic filament can have a draft between 0.2 and 12, and in particular between 1 .0 and 3.0. Further upper and/or lower draft limits of the elastic filament are 0.8, 1 .0, 1 .5, 2.5, 4.0, 6.5, 8.5, 9.0 . Additionally or alternatively, the further filament can have a draft between 1 and 1 .3. Further upper and/or lower draft limits of the further filament are 1 .5, 2.5, 4.0.

The inventive draft values are very different from the known draft values from the prior art used in socks on the market.

In particular, the combination of the (compared with the conventional yarn) lower twist with the lower draft provides further improved properties.

Although the table above only shows a yarn having one single elastic filament and one single inelastic filament, also yarns can be used with cores with two or three elastic filaments and/ or cores which have additionally one or two or three inelastic filaments.

Commonly, the respective twisted core of filaments is covered by a cover layer of staple fibers. The staple fibers may comprise at least one or a mixture of fibers from the group of: natural, recycled and/ or synthetic fibers and/ or fibers made of the following materials: cotton, viscose, polyester, wool, linen, alpaca, vicuna, angora, cashmere, kapok, manila, flax, hemp, ramie, hessian, sisal, coir, asbestos, glass, azlon, acetate, triacetate, acrylic, aramid, polyamide, olefin. The respective fibers made of the aforementioned material may be used as a single material fiber mixture or a composition of any one of the aforementioned different material fibers in one of different lengths. Due to this cover layer, the yarn feels comfortable while it is combined with elastic properties.

The respective described yarn can be used for the production of knitted fabric, in particular machine knitted fabrics, wherein these fabrics have different zones of different knitting patterns. The respective properties in these areas can be changed by the different knitting patterns and by use of the present inventive yarn. It has in particular been shown that socks only consisting of the inventive yarn can be made which are improved in view of stretch recovery and comfort.

Claims

1 . Elastic yarn comprising at least one elastic filament and at least one further filament, which form a core of the yarn, characterized in that the elastic filament has a draft between 0.2 and 15.0, and the further filament has a draft of between 0.2 and 5.0.

2. The elastic yarn according to claim 1 , wherein the at least one elastic filament and the at least one further filament are twisted to form the core of the yarn.

3. The elastic yarn according to any one of claims 1 or 2, wherein the elastic filament has a draft between 0.2 and 12.0.

4. The elastic yarn according to any one of claims 1 to 3, wherein the further filament has a draft of between 1 and 1.3.

5. The elastic yarn according to any one of claims 1 to 4, wherein the further filament is an inelastic filament.

6. The elastic yarn according to any one of claims 1 to 5, wherein the further filament is chosen from the group of polyether sulfones, Polybutylene terephthalate (PBT), Partial Oriented Yarn (POY), polyamide, polyester.

7. The elastic yarn according to any one of claims 1 to 6, wherein the elastic filament is elastane.

8. The elastic yarn according to any one of claims 1 to 7, wherein the core is surrounded by a cover layer to form the yarn, wherein the cover layer comprises staple fibers.

9. The elastic yarn according to any one of claims 1 to 8, wherein the staple fibers are chosen from the group of natural, recycled and/ or synthetic fibers and/ or fibers made of the following materials: cotton, viscose, polyester, wool, linen, alpaca, vicuna, angora, cashmere, kapok, manila, flax, hemp, ramie, hessian, sisal, coir, asbestos, glass, azlon, acetate, triacetate, acrylic, aramid, polyamide, olefin, or a mixture thereof.

10. The elastic yarn according to any one of claims 1 to 9, wherein the core comprises more than 3 filaments and less than 6 filaments, all of which or a part of which are optionally twisted together.

11 . The elastic yarn according to any one of claims 1 to 10, wherein the core comprises 2 or 3 elastic filaments each having a draft between 0.2 and 15.

12. The elastic yarn according to any one of claims 1 to 11 , wherein the core comprises 1 or 2 or 3 inelastic filaments each having a draft of a draft of between 0.2 and 5.

13. A knitted textile material, comprising the yarn according to any of claim 1 to 12, wherein the textile material comprises at least two different knitting pattern, wherein the same yarn material is used as only material setting up the different knitting pattern.

14. A sock which is made entirely form one single type of yarn, wherein the yarn is a yarn according to any of claim 1 to 12, and/or wherein the sock comprises a yarn according to any of claim 1 to 12.

15. A sock which is made of multiple types of core yarn, wherein one of the types is the elastic yarn according to any one of claims 1 to 12.