Patent Description:
Yarns which have electric conductivity may be used in various fields such as clothing applications or in the semi-conductor industry.

<CIT> describes an electrically conductive yarn used for textiles wherein staple and metal fibers are mixed, which mixture then forms the yarn.

In the field of electronics, electrically conductive yarns are e.g. disclosed in <CIT> and <CIT>.

In <CIT>, a core is provided which is encapsulated by first and second electrically conductive layers surrounding the core. This encapsulated wire is also encapsulated by a conventional polymer layer, to provide electric isolation.

In <CIT> metallic filaments are provided, which are embedded in an insulation material, which is encapsulated by a polymer layer to provide an electric isolation.

A further yarn which is an elastic ring spun yarn, is disclosed in <CIT>. To create a natural feeling in combination with high stability and endurance, an elastic core filament is provided, around which further filaments may be twisted by ring spinning. This twisted core is encapsulated by so-called staple fibers, which are made of natural materials, to provide a natural feeling to the yarn.

Further relevant prior art is described in <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>.

The present invention provides a high performance yarn having an improved electric conductivity combined with adaptable surface optic and/or haptic aspects.

In order to solve the aforementioned problem, according to a first arrangement a core yarn having the features defined in claim <NUM> is provided.

In particular, the present invention is focused to a core yarn comprising at least two electrically conductive filaments as a core and a cover layer which encapsulates the core, wherein the cover layer comprises staple fibers, wherein the core further comprises an elastic filament having an elasticity in at least longitudinal direction thereof, wherein the elastic filament is a separate filament and not constituted by the at least two conductive filaments, wherein the at least two conductive filaments are wound around the elastic filament, wherein one of the at least two conductive filaments is a metal filament made of a metallic material, and the other of the at least two conductive filaments is a coated filament having a core of a substantially not electrically conducting material, and a surface layer of an electrically conductive material.

In the following different configurations are described, however the scope of protection is defined by the claims. The further variants described throughout the application, which do not fall under the scope of the claims, are helpful for understanding the present invention.

The core yarn has a cover layer comprising staple fibers. Such staple fibers are distinct fibers which have a certain length. The staple fibers may comprise a plurality of different lengths. Such staple fibers in textile technology are named non-continuous fibers for differentiating these fibers from so-called continuous filament fibers. These filaments may have an indefinite length.

By providing a cover layer, comprising staple fibers or, which is preferable, constituted by staple fibers, the encapsulation of the electrically conductive filaments which serve as the core, ensures the adaptability of the surface properties of the core yarn.

Depending on the utilization of the yarn it may (according to a non-claimed variant) also be enough to provide only one electrically conductive filament instead of at least two electrically conductive filaments. This is in particular the case it the filament is constituted by the later described coated filament, which may have a non-electrically conductive core and an electrically conductive cover layer.

According to the present invention, the core of the composite core yarn further comprises an elastic filament. Elasticity is the ability to deform reversibly under stress. By combining the elasticity with an electric conductivity, the endurance of the yarn can be further improved. In particular, forces may act in longitudinal direction without breaking the complete yarn.

The elasticity may have a young modulus (in GPa) of <NUM> to <NUM>, more preferably <NUM> to <NUM> in particular, <NUM> to <NUM>. Alternatively or additionally the elongation may be in the range of <NUM> to <NUM>%. 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: <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%. The aforementioned values may each separately serve as lower or upper borders.

According to the present invention, the elastic filament is a separate filament which is not constituted by the at least two conductive filaments. Hence, the composite core yarn at least comprises three filaments which at least three filaments make up the core which is embedded in the cover layer comprising staple fibers. By combining at least one, or preferably only one elastic filament, with at least two electrically conductive filaments, the endurance of the yarn can be improved since the stretch abilities are good which reduces the probability that the conductivity of the yarn is distorted if one electrically conductive filament breaks, as there is still a second electrically conductive filament present. While it is advantageous that the electrically conductive filaments are made of a different material and/or constitution, electrically conductive filaments having the same composition and/or constitution are usable as well.

Additionally, the at least one of the electrically conductive filaments may have a respective elasticity to also constitute the elastic filament.

The electing of at least three filaments (which is in accordance with the present invention) provides further possibilities for the adaptability of the composite core yarn. According to the invention, the at least two conductive filaments are wound around the elastic filament. This may be done by a ring spinning technique as is described in <CIT>. When the respective electrically conductive filaments are wound around the elastic filament, there is the advantage that the electrically conductive filaments, which may be filaments having no substantial elasticity, are able to expand in length and not be broken by expansion. When, for example, the electrically conductive filaments are aligned in parallel with respect to each other in the longitudinal direction in the core and not wound around an elastic filament or any other filament, the breakage probability that at least one electrically conductive filament is broken, increases in comparison with the situation where the respective electrically conductive filaments are wound around the elastic filament. By having the different types of electrically conductive filaments, the physical property of the composite core yarn can be tuned.

In particular, by combining an electrically conducting coating with a non-electrical conductive core, the core material basically defines the elongation properties of the filament while the respective coating defines the electric conduction properties. Conversely thereto, when a metal filament is used, this metal filament is very susceptible to breaking which is not the case for the coated filament.

The coated filament may simultaneously provide the elasticity to simultaneously constitute the elastic filament.

According to a further arrangement, the composite core yarn is a ring spun core yarn.

In such ring spinning, the filaments and/or also the staple fiber material which may be supplied as roving, is fed e.g. in drafting rollers and thereafter spun and wound around a rotating spindle. Further details concerning the ring spinning are described in <CIT>, in particular [<NUM>] to [<NUM>] and Fig. <NUM> therof.

The staple fibers may comprise at least one or a mixture of fibers from the group of: natural 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, acryl, aramid, nylon, olefin, which are used to form the cover layer, can be selected from the following: cotton, viscose, polyester, wool, linen, alpaca, vicuna, angora, cashmere, kapok, manila, flax, hemp ramie, jute, sisal, coir, asbestos, glass, azlon, acetate, triacetate, acryl, aramid, nylon, 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. The respective fibers may be natural fibers and/or synthetic fibers. The metal which forms the metal filament or the electrical conductive material of the surface layer of the coated filament may be selected from the following elements or alloys thereof: copper, silver, iron, gold, magnesium, steel. Any other electrically conductive metal or metal alloy may also be utilized.

The respective non-electrically conductive material constituting the core of the coated filament may be selected from the following: polyamide (PA), Polyethersulfon (PES), Polybutylenterephthalat (PBT), Polyethylenterephthalat (PET) and a combination thereof. Any other continuous filament which is made of natural synthetic and regenerated materials can be used as a core of a coated filament.

The metal filament may have a thickness of <NUM>. 0001micron to <NUM> micron. Further preferred thicknesses are: <NUM> micron, <NUM> micron, <NUM> micron; <NUM> micron, <NUM> micron, or any sum or difference of one or more of the aforementioned values. The aforementioned values may each separately serve as lower or upper borders of a thickness range. The thickness on the one hand defines the conductivity as well as the probability that the yarn breaks. Therefore, the selection of the respective metal filament thickness in the aforementioned ranges depends on the desired properties of the final core yarn.

The thickness of the coated filament and/or the thickness of the elastic filament may be between <NUM> or <NUM> denier (corresponding to <NUM> dTex or <NUM>,<NUM> dTex). Further preferred thicknesses are: <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier (corresponding respectively to <NUM>,<NUM> dTex, <NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex or <NUM>,<NUM> dTex). The aforementioned values may each separately serve as lower or upper borders of a thickness range.

Denier is a unit of measurement for the linear mass density of fibers in grams per <NUM> meters of the fiber. This means that <NUM> denier is <NUM> gram per <NUM> meter. In other words, denier is measured in mass of yarn in g per <NUM> meter.

The core yarn itself, which may have the cover layer of staple fibers and at least two filaments, has a thickness preferably between <NUM> and <NUM> denier (corresponding to <NUM> dTex or <NUM>,<NUM> dTex). Further preferred thicknesses are: <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier (corresponding respectively to <NUM><NUM>,<NUM> dText, <NUM> dTex, <NUM>,<NUM> dText, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex or <NUM>,<NUM> dTex). The aforementioned values may each separately serve as lower or upper borders of a thickness range.

According to a further aspect, a woven fabric is provided which comprises the composite core yarn described in the foregoing section. In particular, the composite core yarn may constitute the warp and/or weft yarn of the woven fabric.

However, the present invention is not delimited to woven fabrics. Also other fabrics like knitted fabric, or non woven fabrics can contain the yarn as a component or may be completely set up of this yarn. The inventive yarn may be used in circular knitted and/or in flat knitted fabrics.

A knitted fabric comprising the inventive composite core yarn may also be provided.

According to a further aspect, an article of clothing is provided which comprises the aforementioned composite core yarn.

The article of clothing includes shoes, t-shirts, jackets, but however, first layer clothing such as socks, underwear t-shirts are preferred because the functionality of the articles with the electric conductivity may then provide a better transmission/contact with the human body, when a human being wears the respective article. However, the article of clothing is not delimited thereto and may be any article of clothing.

In the article of clothing, one or more wire paths may be provided. The wire path is comprised of the composite core yarn or may be in particular constituted by the composite core yarn, having a configuration which is described in the foregoing section.

The wire path may extend within the woven fabric or may be embroidered on the material of which the article of clothing is made.

The wire path may be a distinctive path which extends from one specific location of the clothing to a second specific location of the clothing to allow the selective transfer of signals between the respective two locations.

The respective article of clothing may have one or more electrodes which are connected to a respective end of one wire path and the other end of the wire path may be connectable to a control station, which control station is adapted to communicate with the electrode.

By doing so it is not necessary to provide distinct, commonly known cables from the location where the control station is mounted, to the location where the electrodes which may serve as sensors for sensing body functions, are provided.

Each respective wire path may have an electrically non-conductive coating which prevents the transfer of the electric current in the radial direction of the wire path to the surrounding area.

A pocket for containing the respective control station may be incorporated in the clothing. The control station may be connected to respective terminals which are provided at ends of the respective wire paths to transfer signals via the wire paths to the electrodes.

The electrodes may be electrode pads. Electrode pads may be patches of a conductive material, for example, a woven or non-woven textile material which is integrally formed in the article of clothing.

The article of clothing may have a plurality of wire paths which are connected to respective electrodes wherein at least one electrode is positioned in the region of the human heart and at least a further electrode is positioned at an extremity of the human body, for example at one or both shoulders, and/or at one or both hips and/or at one or both knees, and/or at one or both feet, and/or at one or both hands.

With such a constitution, physical functions, in particular, heart functions may be measured.

It is preferred that the respective article of clothing has a certain compression functionality and thus is a piece of compression clothing as otherwise the respective interaction of the sensors/electrodes and the human body is probably not sufficient for receiving good signals to track the physical activity of the human body.

The control station may be adapted to supply an electric current to the electrodes and to receive information from the electrodes to display a physical activity of the human body.

According to a further aspect, a method according to claim <NUM>, is provided for producing a composite core yarn.

Examples of such spinning methods are ring spinning, open end spinning and air jet spinning. However, in particular the utilization of a ring spinning method is advantageous.

The use of the aforementioned composite core yarn is disclosed for at least one of the following aspects: use in mobile devices, use in sensor elements, use as filter elements, use in health care facilities, use for microwave applications, use in sportswear, use in health gear, use in smart textiles and use in gloves and for use in soft rooftops for convertible automobiles. Further areas of utilization are any areas where the following technical functions are advantageous conductive properties, anti-static properties, anti-bacterial properties, anti-fungal properties, electromagnetic shielding properties.

For facilitating the understanding of the invention, some specific embodiments are explained in the following which, however, do not limit the scope of the general description.

The respective features, which are mentioned in the foregoing, and the distinct features outlined in the following with respect to the specific examples may be combined with each other in any form.

A sketch of a ring spinning machine is shown in <FIG>. Reference numbers <NUM> to <NUM> as denoted in <FIG> are bobbins from which the roving <NUM> (bobbin having reference number <NUM>) or filaments (bobbins having reference numbers <NUM>, <NUM> and <NUM>) are supplied to a respective drafting <NUM>, <NUM>, <NUM>, <NUM> stage which comprises drafting rollers.

The roving or filament are supplied from the bobbins <NUM>, <NUM>, <NUM>, and <NUM> to the drafting rollers contained in a respective drafting stage <NUM>, <NUM>, <NUM>, <NUM>), where the material is drafted between the drafting rollers. From the stage the drafted material is supplied to a spindle <NUM> (ring spinning spindle).

The respective set up shown in <FIG> is not intended to delimit the invention. However, the respective bobbins <NUM>, <NUM>, <NUM>, <NUM> as well as the respective drafting stages <NUM>, <NUM>, <NUM>, <NUM> each may be provided one after each other and adjacent to each other in the horizontal or in the vertical direction.

Moreover it should be noted, that in <FIG> there is only shown one section for producing one single inventive yarn. However, two or more of said sections may be placed one after each other in the horizontal direction. Each section may be one unit wherein a plurality of units may be provided one subsequent to the other to make a plurality of yarns simultaneously.

Between the drafting stage and the spindle in the present stage a twisting stage <NUM> is provided wherein in the present arrangement shown in <FIG> the filaments <NUM>, <NUM>, and <NUM> from the bobbins <NUM>, <NUM> and <NUM> are first wound around each other and, thus, twisted.

Downstream of the twisting stage <NUM> and upstream of the spindle <NUM> there is an encapsulation stage <NUM> provided wherein the respective roving <NUM>, comprising the staple fibers, is made to form the cover layer encapsulating the twisted core, which is constituted by the filament <NUM>, <NUM> and <NUM>.

In the example shown in <FIG>, the respective filament having reference sign <NUM> is a metal filament which is made of a metal material, the filament having reference sign <NUM> is a coated filament having a core of a substantially not electrically conductive material and a surface layer of an electric conductive material and the filament with reference sign <NUM> is an elastic filament having a certain elasticity in at least the longitudinal direction.

In the case in <FIG>, the respective metal filament <NUM> and the coated filament <NUM> are wound around the elastic filament <NUM> in the twisting stage <NUM>.

Thereafter, the roving, comprising the staple fibers, is provided in the encapsulation stage <NUM> to form an encapsulating cover layer to the core which is made up of the metal filament <NUM>, the coated filament <NUM> and the elastic filament <NUM>.

Although in the present case, a ring spinning is described, the preparation of the composite core yarn is not delimited to the method of ring spanning, but can be made by any method which is able to provide a cover layer which encapsulates the core which comprises one or more filaments. Alternatives of such ring spinning methods are open end spinning and air jet spinning.

The at least two conductive filaments are selected from the group of the following: a) a metal filament made of a metallic material, and b) a coated filament. The coated filament has a core of a substantially not electrical conducting material and a surface layer of an electrical conductive material. It is so that one of the at least two filaments is the metal filament and that the at least second of the filaments, is the coated filament. By having the different types of electrically conductive filaments, the physical properties of the composite core yarn can be adapted.

The elastic filament is a separate filament which is not constituted by the at least two conductive filaments. Hence, the composite core yarn at least comprises three filaments which at least three filaments make up the core which is embedded in the cover layer comprising staple fibers. By combining at least one, or preferably only one elastic filament with at least two electrically conductive filaments, the endurance of the yarn can be improved, as the stretch abilities are good, and the probability that the conductivity in the yarn is distorted if one electrically conductive filament breaks, is reduced as there is still a second electrically conductive filament present. It is advantageous that the electrically conductive filaments are made of a different material and/or constitution, but however also electrically conductive filaments having the same composition and/or constitution are useable.

Staple fibers in the meaning of the present invention are fibers or clusters of fibers which have a single or different length. Conversely thereto, a filament is a single fiber having a substantially indefinite length.

This explanation corresponds to the understanding of "staple fiber" and "filament" in the textile industry.

A composite core yarn which is generated by ring spinning, as described with reference to <FIG>, is shown in <FIG>.

In <FIG>, the inner center of the core of the composite core yarn is constituted by the elastic filament <NUM> while the respective electrically conductive filaments <NUM>, <NUM>, in particular the metal filament <NUM> and the coated filament <NUM>, is wound around the elastic filament.

The staple fibers may comprise at least one or a mixture of fibers from the group of: natural, 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, acryl, aramid, nylon, olefin which are used to form the cover layer can be selected from the following: cotton, viscose, polyester, wool, linen, alpaca, vicuna, angora, cashmere, kapok, manila, flax, hemp ramie, jute, sisal, coir, asbestos, glass, azlon, acetate, triacetate, acryl, aramid, nylon, 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. The respective fibers may be natural fibers and/or synthetic fibers.

The metal which forms the metal filament <NUM> or the electrically conductive material of the surface layer of the coated filament <NUM>, may be selected from the following elements or alloys thereof: copper, silver, iron, gold, magnesium, steel.

The respective non-electrically conductive material constituting the core of the coated filament <NUM> may be selected from the following: polyamide (PA), Polyethersulfon (PES), Polybutylenterephthalat (PBT), Polyethylenterephthalat (PET) and a combination thereof.

The metal filament <NUM> may have a thickness of <NUM>. 0001micron to <NUM> micron. Further preferred thicknesses are: <NUM> micron, <NUM> micron, <NUM> micron; <NUM> micron, <NUM> micron, or any sum or difference of one or more of the aforementioned values.

The aforementioned values may each separately serve as lower or upper borders of a thickness range. The thickness on the one hand defines the conductivity as well as the probability that the yarn breaks. Therefore, the selection of the respective metal filament thickness in the aforementioned ranges depends on the desired properties of the final core yarn.

The thickness of the coated filament <NUM> and/or the thickness of the elastic filament <NUM> may be between <NUM> or <NUM> denier (corresponding to <NUM> dTex or <NUM>,<NUM> dTex). Further preferred thicknesses are: <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier (corresponding respectively to <NUM><NUM>,<NUM> dTex, <NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex or <NUM>,<NUM> dTex). The aforementioned values may each separately serve as lower or upper borders of a thickness range.

Denier is a unit of measurement for the linear mass density of fibers in grams per <NUM> meters of the fiber. This means that <NUM> denier is <NUM> gram per <NUM> meter.

The core yarn itself, which may have the cover layer of staple fibers and at least two filaments, has a thickness preferably between <NUM> and <NUM> denier (corresponding to <NUM> dTex or <NUM>,<NUM> dTex). Further preferred thicknesses are: <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier, <NUM> denier (corresponding respectively to <NUM><NUM>,<NUM> dTex, <NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex, <NUM>,<NUM> dTex or <NUM>,<NUM> dTex). The aforementioned values may each separately serve as lower or upper borders of a thickness range.

In the embodiment shown in <FIG>, first the respective elastic filament <NUM> twisted together with the metal filament <NUM> and the coated filament <NUM> before the encapsulation with the staple fibers is done. However, any further, alternative sequence may be used. For example, only two fibers may be twisted or only a single fiber may be encapsulated by the staple fibers. It is also shown in this figure that one of the electrically conductive filaments is a metal filament and that the other filament is a coated electrically conductive filament, this is also not essential and any combination thereof also more than two electrically conductive filaments can be used which can be wound around an elastic filament or which may be aligned in parallel to each other.

This composite core yarn may be used for providing one or more electric paths <NUM> in an article of clothing.

An example of such an article of clothing is the t-shirt shown in <FIG>.

Other examples of articles of clothing are for instance, shoes, gloves, socks, underwear, t-shirts, pullovers and jackets may also be used. However, first layer clothing such as socks, underwear t-shirts are preferred, because the functionality of the articles with the electric conductivity may then provide a better transmission/contact with the human body, when a human being wears the respective article. However, the article of clothing is not delimited thereto and may be any article of clothing.

It is shown in <FIG> that there are provided in total <NUM> electrically conductive paths <NUM> which connect a respective control station <NUM> with respective electrodes <NUM>, <NUM>, <NUM>. The group of electrodes having reference sign <NUM>, are provided on the t-shirt in a region of the heart of a human being. The respective electrodes having reference sign <NUM> are provided at the extremities of the main body, in particular, at both front sides of the shoulders. The respective electrodes having reference sign <NUM> are provided at the extremities of the main body, in particular, at both and both front sides of the hips.

Between the respective electrodes which are made in the present embodiment as electrode pads, and the control station <NUM> signals can be transferred via the wire paths <NUM>. Thus, a physical activity of the heart or any other physical activity may be measured.

The electrode pads may be made of an electrically conductive material, also a woven or nonwoven material which is integrally formed in the material of the t-shirt or the article of clothing itself.

The respective control station <NUM> may be mounted deconnectably from respective plug/s which are provided at the ends of the wire paths <NUM>.

The respective control station <NUM> may be provided in a pocket <NUM> of the clothing.

Via an Application (App) on a mobile device, the respective control station <NUM> may be controlled e.g. by means of wireless communication.

The respective wire path may be encapsulated in a non-conductive material such that a non-conductive coating prevents a transfer of an electric current between the wire path core and the radial surrounding area.

In particular, the wire path may be embroidered in the article of clothing.

However, any other attachments to the article of clothing are also possible.

Claim 1:
Composite core yarn comprising at least two electrically conductive filaments (<NUM>, <NUM>) as a core and a cover layer (<NUM>) which encapsulates the core, wherein the cover layer (<NUM>) comprises staple fibers, wherein the core further comprises an elastic filament (<NUM>) having an elasticity in at least longitudinal direction thereof, wherein the elastic filament (<NUM>) is a separate filament and not constituted by the at least two conductive filaments (<NUM>, <NUM>), wherein the at least two conductive filaments (<NUM>, <NUM>) are wound around the elastic filament (<NUM>), wherein one of the at least two conductive filaments (<NUM>, <NUM>) is a metal filament (<NUM>) made of a metallic material; and the other of the at least two conductive filaments (<NUM>, <NUM>) is a coated filament (<NUM>) having a core of a substantially not electrically conducting material, and a surface layer of an electrically conductive material.