CN114929956A

CN114929956A - Yarn and cloth

Info

Publication number: CN114929956A
Application number: CN202180008141.6A
Authority: CN
Inventors: 森健一; 玉仓大次; 辻雅之; 宅见健一郎; 藤堂良; 林宏和
Original assignee: Murata Manufacturing Co Ltd; Teijin Frontier Co Ltd
Current assignee: Murata Manufacturing Co Ltd; Teijin Frontier Co Ltd
Priority date: 2020-01-08
Filing date: 2021-01-07
Publication date: 2022-08-19
Also published as: JP7431256B2; EP4071284A1; JPWO2021141089A1; EP4071284A4; WO2021141089A1; US20220364277A1

Abstract

The invention provides a yarn with a potential generating filament. The yarn is characterized in that the relative dielectric constant of the yarn is 4.5 or less. Further, a fabric comprising the yarn is provided.

Description

Yarn and cloth

Technical Field

The present invention relates to a yarn, and more particularly, to a yarn that forms an electric field by surface charge, and more particularly, can generate an electric potential. The present invention also relates to a fabric, and more particularly to a fabric including the yarn.

Background

Hitherto, a large number of antibacterial fiber materials have been proposed (for example, patent documents 1 to 8).

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 3281640

Patent document 2: japanese laid-open patent publication No. 7-310284

Patent document 3: japanese patent No. 3165992

Patent document 4: japanese patent No. 1805853

Patent document 5: japanese laid-open patent publication No. 8-226078

Patent document 6: japanese patent laid-open publication No. 9-194304

Patent document 7: japanese patent laid-open publication No. 2004-300650

Patent document 8: japanese patent No. 6428979

Disclosure of Invention

The present inventors have paid attention to the problems to be overcome in the conventional antibacterial fiber materials, and have found that improvements therefor are required. Specifically, the present inventors have found the following problems.

As a conventional fiber material having antibacterial properties, an antibacterial yarn is known which includes a plurality of charge-generating fibers that generate charges by external energy such as tension (for example, patent document 8). Such an antibacterial yarn is characterized in that spaces between a plurality of charge-generating fibers are in different states, and thus, variations in electrical characteristics occur, a strong electric field is locally formed, and antibacterial properties are exhibited.

However, the present inventors found, through their studies, that: the state of the space between the charge generating fibers, particularly, physical properties such as the dielectric constant of the dielectric substance present between the charge generating fibers, may reduce the electric field strength of the formed electric field, and thus antibacterial properties may not be obtained. In addition, physical properties that can easily confirm antibacterial properties are still being established.

In view of the above problems, it is a main object of the present invention to find a yarn which can more reliably obtain antibacterial property values and can be used as an antibacterial yarn. Another object of the present invention is to provide a fabric comprising the yarn.

The present inventors have conducted intensive studies and, as a result, have found that: as the physical properties of a yarn having a charge-generating fiber (in other words, a fiber or filament (hereinafter also referred to as "potential-generating filament" or "electric field-forming filament") capable of generating a potential and forming an electric field by generating a charge as described in detail below), attention is paid to a dielectric constant, particularly a "relative dielectric constant", and a value thereof is set to "about 4.5 or less", so that the antibacterial property is easily and more reliably obtained, and the yarn can be favorably used as an antibacterial yarn. As a result, the invention of the yarn that can achieve the main object described above has been finally completed.

The present invention provides a yarn having a potential generating filament, characterized in that the yarn has a relative dielectric constant of about 4.5 or less. The present invention also provides a fabric comprising the yarn.

According to the present invention, it is possible to provide products such as a yarn (more preferably, an antibacterial yarn) capable of more reliably exhibiting antibacterial properties, and a cloth (more preferably, an antibacterial cloth) including such a yarn.

Drawings

Fig. 1(a) is a view showing a structure of a yarn 1(S yarn), fig. 1(B) is a cross-sectional view taken along line a-a of fig. 1(a), and fig. 1(C) is a cross-sectional view taken along line B-B of fig. 1 (a).

Fig. 2(a) and 2(B) are diagrams showing the relationship between the uniaxial stretching direction of polylactic acid, the electric field direction, and the strain of the potential generating filament (or piezoelectric fiber) 10.

Fig. 3(a) is a view showing the structure of the yarn 2(Z yarn), fig. 3(B) is a cross-sectional view taken along line a-a of fig. 3(a), and fig. 3(C) is a cross-sectional view taken along line B-B of fig. 3 (a).

Fig. 4 is a cross-sectional view schematically showing a cross section of the yarn of the present invention provided with the dielectric 100 around the potential generating filament 10.

FIG. 5 is a graph showing the relationship between the relative permittivity (. epsilon.) of a dielectric and the electric field strength (V/μm).

Fig. 6 is a schematic view schematically showing a method of measuring the impedance of the yarn of the present invention using an LCR meter.

FIG. 7 is a graph showing the relationship between the interval d (μm) of the potential generating filaments and the electric field intensity (V/μm).

Fig. 8 shows the results of a preliminary test for confirming the antibacterial action by the electric stimulation.

FIG. 9(a) is a photograph showing the condition of Trichophyton Trichophyton (Trichophyton) before and after voltage application for the 20 V.times.5 Hz sample and FIG. 9(b) is a photograph showing the condition of Trichophyton Trichophyton before and after voltage application for the same 50 V.times.5 Hz sample in the table of FIG. 8.

Fig. 10 is a photograph showing trichophyton used in preliminary tests.

Fig. 11 is a schematic diagram schematically illustrating a method of making a sample of yarn bundles.

Fig. 12 is a photograph showing an example of a method for measuring the relative dielectric constant of a yarn using a yarn bundle sample.

Fig. 13 is a schematic view schematically showing a method of measuring the relative dielectric constant of the yarns in the yarn bundle sample.

Detailed Description

Hereinafter, a yarn according to an embodiment of the present invention (hereinafter, also referred to as "the yarn of the present invention" or simply as "the yarn") will be described in detail. The various elements in the drawings are merely schematic and exemplary illustrations for the purpose of understanding the present invention, and are not intended to differ in appearance, size ratio, etc. from the actual ones.

The yarn of the present invention has a "potential generating filament", and is characterized in that the "relative dielectric constant" as a physical property thereof is about 4.5 or less. With such a configuration and characteristics, the yarn of the present invention can more reliably exhibit the "antibacterial property" described in detail below, and can be used as an "antibacterial yarn".

In the present specification, unless a specific term such as "less than", "more than" or "more than" is used, various numerical ranges include lower and/or upper limits. That is, for example, a numerical range of 1 to 10 is taken as an example, and unless otherwise specified, "1" including the lower limit value and "10" including the upper limit value can be interpreted.

In addition, various numerical values may be labeled with "about", and the term "about" means that the fluctuation may include several%, for example, about ± 9%, 4%, 2%, or ± 1%.

Hereinafter, the following description will be made in detail about [ basic structure of yarn ] and [ characteristics of yarn ].

[ basic constitution of yarn ]

The yarn of the present invention is formed, for example, by having a plurality of "potential generating filaments" or "electric field forming filaments". The number of the potential generating filaments or the electric field forming filaments is not particularly limited, and for example, the yarn of the present invention may contain 2 or more, 2 to 500, preferably 10 to 350, and more preferably about 20 to 200 potential generating filaments.

In the present invention, the "potential generating filament" or "electric field forming filament" refers to a fiber (or filament) that generates an electric charge by external energy to generate a potential and form an electric field (hereinafter, also referred to as "charge generating fiber" or "charge generating filament" or "electric field forming fiber").

The term "potential generating filament" may be substantially the same as the term "electric field forming filament".

The "energy from the outside" acceptable for the potential generation filament includes, for example, an external force (hereinafter, also referred to as "external force") such as, specifically, a force for generating a strain or strain in the yarn or filament, and/or a force applied to the yarn or filament in the axial direction, more specifically, a tension (for example, a tensile force in the axial direction of the yarn or filament), and/or an external force such as a stress or strain (tensile stress or tensile strain applied to the yarn or filament), and/or a force applied to the yarn or filament in the transverse direction.

The size (length, thickness (diameter), etc.) and shape (cross-sectional shape, etc.) of the potential generating filament are not particularly limited. The yarn of the present invention having such potential generating filaments may contain a plurality of potential generating filaments having different thicknesses. Thus, the yarn of the invention may or may not have a constant diameter in the lengthwise direction.

The potential generating filaments may be long fibers or short fibers. The potential generating filament has, for example, a length (or size) of 0.01mm or more, preferably a length (or size) of 0.1mm or more, more preferably a length (or size) of 1mm or more, and still more preferably a length (or size) of 10mm or more, or 20mm or more, or 30mm or more. The length may be appropriately selected depending on the intended use. The upper limit of the length is not particularly limited, and is, for example, 10000mm, 100mm, 50mm or 15 mm.

The thickness of the potential generating filament, that is, the filament diameter is not particularly limited, and may be the same (or a constant value) or different along the length of the potential generating filament. The potential generating filament may have a single fiber diameter of, for example, 0.001 μm (1nm) to 1mm, preferably 0.01 μm to 500 μm, more preferably 0.1 μm to 100 μm, particularly preferably 1 μm to 50 μm, for example, 10 μm or 30 μm. The single fiber diameter may be appropriately selected depending on the intended use.

The shape, particularly the cross-sectional shape, of the potential generating filament is not particularly limited, and may have a circular, elliptical, or irregular cross-section, for example. Preferably having a circular cross-sectional shape.

The potential generating filament is preferably formed from: a material having a photoelectric effect, a material having a pyroelectric effect, or a material having a piezoelectric effect (a polarization phenomenon caused by an external force) or piezoelectricity (a property of generating a voltage when a mechanical strain is applied or, conversely, generating a mechanical strain when a voltage is applied) (hereinafter, may be referred to as a "piezoelectric material" or a "piezoelectric body"). Among them, a fiber containing a piezoelectric material (hereinafter, also referred to as "piezoelectric fiber") is particularly preferably used. The piezoelectric fibers form an electric field by piezoelectric, and more specifically, since an electric potential can be generated, there is no need for a power supply and no risk of induction. In addition, the piezoelectric fibers may contain a piezoelectric material whose life lasts longer than the antibacterial effect of a medicament or the like. In addition, such piezoelectric fibers are also less likely to cause allergic reactions.

The "piezoelectric material" is not particularly limited as long as it has a piezoelectric effect or piezoelectricity, and may be an inorganic material such as piezoelectric ceramics or an organic material such as a polymer.

The "piezoelectric material" (or "piezoelectric fiber") preferably comprises a "piezoelectric polymer".

Examples of the "piezoelectric polymer" include "piezoelectric polymers having pyroelectric properties" and "piezoelectric polymers having no pyroelectric properties".

The "piezoelectric polymer having a pyroelectric property" generally refers to a piezoelectric material formed of a polymer material having a pyroelectric property and capable of generating an electric charge on the surface thereof by giving a temperature change. Examples of such piezoelectric polymers include polyvinylidene fluoride (PVDF). Particularly preferred are polymers capable of generating electric charges on their surfaces by the thermal energy of the human body.

The "piezoelectric polymer having no pyroelectric property" generally refers to a piezoelectric polymer (hereinafter, also referred to as "polymeric piezoelectric body") formed of a polymer material (polymer material or resin material) other than the "piezoelectric polymer having pyroelectric property". Examples of such piezoelectric polymers include polylactic acid (PLA).

As polylactic acid (PLA), poly-L-lactic acid (PLLA) obtained by polymerizing an L-type monomer (in other words, a polymer substantially composed of only a repeating unit derived from an L-lactic acid monomer), poly-D-lactic acid (PDLA) obtained by polymerizing a D-type monomer (in other words, a polymer substantially composed of only a repeating unit derived from a D-lactic acid monomer), a mixture thereof, and the like are known.

As the polylactic acid (PLA), a copolymer of L-lactic acid and/or D-lactic acid and a compound copolymerizable with the L-lactic acid and/or D-lactic acid may also be used.

Further, a mixture of "polylactic acid (a polymer substantially composed of a repeating unit of a monomer selected from L-lactic acid and D-lactic acid)" and "a copolymer of L-lactic acid and/or D-lactic acid and a compound copolymerizable with the L-lactic acid and/or D-lactic acid" may be used.

In the present invention, a polymer containing the polylactic acid is referred to as a "polylactic acid-based polymer". In other words, the "polylactic acid-based polymer" refers to "polylactic acid (a polymer substantially composed of a repeating unit of a monomer selected from L-lactic acid and D-lactic acid)", "a copolymer of L-lactic acid and/or D-lactic acid and a compound copolymerizable with the L-lactic acid and/or D-lactic acid", and a mixture thereof.

Among polylactic acid polymers, "polylactic acid" is particularly preferable, and a homopolymer of L-lactic acid (PLLA) and a homopolymer of D-lactic acid (PDLA) are most preferably used.

The polylactic acid-based polymer may have a crystalline portion, or at least a portion of the polymer may be crystallized. As the polylactic acid-based polymer, a polylactic acid-based polymer having piezoelectricity, in other words, a piezoelectric polylactic acid-based polymer, particularly a piezoelectric polylactic acid, is preferably used.

In addition to polylactic acid-based polymers, for example, optically active polymers such as polypeptide-based polymers (e.g., poly (γ -benzyl glutarate), poly (γ -methyl glutarate), etc.), cellulose-based polymers (e.g., cellulose acetate, cyanoethyl cellulose, etc.), polybutanoic acid-based polymers (e.g., poly (β -hydroxybutyric acid), etc.), polypropylene oxide-based polymers, and derivatives thereof can be used as the piezoelectric polymer.

The yarn of the present invention may have the following structure: as the potential generating filament (or charge generating fiber), a structure is used in which a conductor is used as the core yarn, an insulator is wound around the conductor, and a voltage is applied to the conductor to generate a charge or a potential.

The yarn of the present invention may be a yarn (a twisted yarn or a non-twisted yarn) obtained by simply twisting a plurality of potential generating filaments, a yarn (a twisted yarn or a twisted yarn) having a twist, or a yarn (a crimped yarn or a false twisted yarn) having crimp.

For example, as shown in fig. 1(a), the yarn 1 may be constructed by twisting a plurality of potential generating filaments 10. In the embodiment shown in fig. 1 a, the yarn 1 is a left-handed yarn (hereinafter, referred to as "S yarn") in which the potential generating filaments 10 are twisted left-handed, or may be a right-handed yarn (hereinafter, referred to as "Z yarn") in which the potential generating filaments 10 are twisted right-handed (see, for example, the yarn 2 in fig. 3 a). As described above, the yarn of the present invention may be either of the "S yarn" and the "Z yarn" when the yarn is twisted.

In the yarn of the invention, the spacing between the potential generating filaments 10 is from about 0 μm to about 10 μm, typically around 5 μm. When the interval between the potential generating filaments 10 is 0 μm, the potential generating filaments are in contact with each other. Within the above range, the yarn of the present invention can preferably have a dielectric constant value of "about 4.5 or less" which is an object to be described in detail below, and can more reliably exhibit antibacterial properties.

Here, the relative permittivity of the yarn of the present invention refers to a ratio of the permittivity of the yarn of the present invention to the permittivity of vacuum ([ relative permittivity of yarn of the present invention ]/[ permittivity of vacuum ]). The relative permittivity is a dimensionless value, and may be referred to as a relative permittivity or a dielectric constant.

The relative dielectric constant of the yarn of the invention can be determined, for example, as follows: the yarn is passed between the parallel plate capacitors, the electrostatic capacity is measured, the electrostatic capacity of the yarn is calculated from the difference with the electrostatic capacity when the yarn has not passed, the dielectric constant of the yarn of the present invention is determined by using the value and the yarn capacity, and the dielectric constant of the yarn is calculated by using the dielectric constant of vacuum based on the above equation.

The method of determining the relative dielectric constant of the yarn is not limited to the above-described method. For example, as described in detail with reference to the photograph and the like of FIG. 12, particularly FIG. 12B, the relative dielectric constant of the yarn of the present invention can be directly measured by using a measuring machine such as an LCR Meter (for example, Precision LCR Meter (model E4980A) manufactured by Agilent). In this case, the relative dielectric constant of the yarn can be directly measured using a yarn bundle (sample) formed by collecting the yarns of the present invention (see fig. 11 to 13).

The measured value of the relative permittivity of the yarn bundle is substantially the same as the calculated value of the relative permittivity of the yarn (one) of the present invention based on the above-mentioned electrostatic capacity.

Hereinafter, in order to describe the yarn of the present invention in detail, a mode in which a piezoelectric material is contained as a potential generating filament and the piezoelectric material is "polylactic acid" is given as an example, and the yarn of the present invention is described in more detail with reference to fig. 1 to 3.

Polylactic acid (PLA) that can be used as a piezoelectric material is a chiral polymer, and has a main chain having a helical structure. In polylactic acid, piezoelectricity can be exhibited if molecules are oriented by uniaxial stretching. Further, the crystallinity can be increased by applying heat treatment, thereby increasing the piezoelectric constant. In other words, the "piezoelectric constant" can be improved by the "crystallinity" (refer to "study of mechanism of expression of high piezoelectric property of solid-phase stretched film using polylactic acid", academic society, 40, 1(2016)38 to 43).

The optical purity of polylactic acid (PLA) as a piezoelectric material was calculated according to the following formula.

Optical purity (%) { | L-form amount-D-form amount |/(L-form amount + D-form amount) } × 100

For example, in either of the D-form and the L-form, the optical purity is 90% by weight or more, preferably 95% by weight or more, more preferably 98% by weight to 100% by weight, still more preferably 99.0% by weight to 100% by weight, and particularly preferably 99.0% by weight to 99.8% by weight. The L form amount and D form amount of polylactic acid (PLA) can be obtained, for example, by a method using High Performance Liquid Chromatography (HPLC).

The crystallinity of polylactic acid (PLA) is characterized by, for example, 35% or more (specifically, 35% to 45%, more specifically, 42% to 44%), more preferably 50% or more, and still more preferably 55% to 100%. The crystallinity can be determined by a measurement method such as a Differential Scanning calorimeter (DSC: Differential Scanning Calorimetry) (for example, DSC7000X manufactured by Hitachi High-Tech Science Company), an X-ray diffraction method (XRD: X-ray diffraction) (for example, X-ray diffraction method using ultraX 18 manufactured by Rigaku Corporation), and the like. If the crystallinity is within the above range, the electric charge and potential that can be generated in the yarn can be more appropriately controlled.

As shown in FIG. 1A, in a potential generating filament (or piezoelectric fiber) 10 comprising uniaxially stretched polylactic acid, when the thickness direction is defined as the 1 st axis, the stretching direction 900 is defined as the 3 rd axis, and the direction perpendicular to both the 1 st axis and the 3 rd axis is defined as the 2 nd axis, the filament has d as a piezoelectric strain constant ₁₄ And d ₂₅ The tensor component of (a).

Therefore, when the polylactic acid is strained in a direction of 45 degrees with respect to the direction of uniaxial stretching, electric charges or electric potentials can be generated most efficiently.

The polylactic acid has a number average molecular weight (Mn) of, for example, 6.2X 10 ⁴ The weight-average molecular weight (Mw) is, for example, 1.5X 10 ⁵ . The molecular weight is not limited to these values.

Fig. 2 a and 2B are diagrams showing the relationship between the uniaxial stretching direction of polylactic acid, the electric field direction, and the strain of the potential generating filament (or piezoelectric fiber) 10.

As shown in fig. 2(a), if the filament 10 contracts in the direction of the 1 st diagonal line 910A and expands in the direction of the 2 nd diagonal line 910B orthogonal to the 1 st diagonal line 910A, an electric field can be generated in the direction from the back side to the front side of the paper surface. That is, the filament 10 can generate a negative charge or potential on the surface side of the paper. As shown in fig. 2(B), even when the filament 10 is elongated in the direction of the 1 st diagonal line 910A and contracted in the direction of the 2 nd diagonal line 910B, electric charges can be generated, but the polarity is reversed, and an electric field can be generated in the direction from the front surface to the back surface of the paper surface. That is, the filament 10 can generate a positive charge or potential on the surface side of the paper.

In polylactic acid, since piezoelectricity is generated by orientation treatment, crystallinity, and the like of stretched molecules, polarization (poling) treatment is not required unlike other piezoelectric polymers such as polyvinylidene fluoride (PVDF) and piezoelectric ceramics. The uniaxially stretched polylactic acid has a piezoelectric constant of about 5 to 30pC/N, and has a very high piezoelectric constant in a polymer. Further, the piezoelectric constant of polylactic acid is extremely stable without time variation.

The potential generating filament 10 is preferably a fiber having a circular cross section. The potential generating filament 10 can be produced, for example, by the following method: a method of fiberizing a piezoelectric polymer by extrusion molding, a method of fiberizing a piezoelectric polymer by melt spinning (for example, a spinning and drawing method in which a spinning step and a drawing step are separately performed, a straight drawing method in which a spinning step and a drawing step are connected, a POY-DTY method in which a false twisting step can be simultaneously performed, an ultra-high-speed spinning method in which a high speed is realized, or the like), a method of fibrillating a piezoelectric polymer by dry or wet spinning (for example, a phase separation method or a dry-wet spinning method in which a polymer to be a raw material is dissolved in a solvent and extruded from a nozzle to be fibrillated, a gel spinning method in which the polymer is homogeneously fibrillated into a gel state in a state of containing a solvent, a liquid crystal spinning method in which a liquid crystal solution or a melt is used for fibrillating, or a method of fibrillating a piezoelectric polymer by electrostatic spinning). The cross-sectional shape of the fiber 10 is not limited to a circular shape.

For example, the yarn 1 shown in fig. 1 may be a yarn (multifilament yarn) (S yarn) obtained by twisting a plurality of potential generating filaments 10 containing such polylactic acid. The number of filaments 10 constituting the yarn 1 is not particularly limited. The drawing direction 900 of each potential generating filament 10 coincides with the axial direction of the respective potential generating filament 10. Therefore, the drawing direction 900 of the potential generating filament 10 is inclined to the left with respect to the axial direction of the yarn 1. Note that the angle thereof depends on the number of twists.

When tension is applied to the yarn 1 as such an S yarn, a negative charge or potential is generated on the surface of the yarn 1, and a positive charge or potential is generated on the inner side thereof.

The yarn 1 may form an electric field by means of a potential difference that can be generated by this charge. The electric field may leak to a nearby space to form a combined electric field with other parts. Further, when the electric potential that can be generated in the yarn 1 is close to an object having an adjacent predetermined electric potential, for example, a predetermined electric potential (including a ground electric potential) such as a human body, an electric field can be generated between the yarn 1 and the object.

Next, referring to fig. 3, since the yarn 2 is a Z-yarn, the stretching direction 900 of the potential generating filament (or piezoelectric fiber) 10 is inclined rightward with respect to the axial direction of the yarn 2. The angle depends on the number of twists of the yarn. The number of filaments 10 constituting the yarn 2 is not particularly limited.

When tension is applied to the yarn 2 as such a Z yarn, a positive charge or potential is generated on the surface of the yarn 2, and a negative charge or potential is generated on the inner side thereof.

The yarn 2 may also be subjected to an electric field by means of a potential difference that can be generated by this charge. The electric field may leak to a nearby space to form a combined electric field with other parts. When the electric potential that can be generated in the yarn 2 is close to an object having an adjacent predetermined electric potential, for example, a predetermined electric potential (including a ground electric potential) such as a human body, an electric field can be generated between the yarn 2 and the object.

Further, when the yarn 1 as the S yarn and the yarn 2 as the Z yarn are close to each other, an electric field or a potential can be generated between the

yarns

1 and 2.

The polarity of the charges or potentials that can be generated in the

yarns

1 and 2 are different from each other. The potential difference at each location can be defined by an electric field coupling circuit formed by intricately winding fibers around each other or a circuit formed by a current path accidentally formed in the yarn due to moisture or the like.

The yarns of the present invention are not to be construed in a limiting manner in the above manner. The method for producing the yarn of the present invention is not particularly limited, and is not limited to the above-described production method.

Furthermore, the yarn of the present invention may be provided with a "dielectric" on at least a part of the periphery of the potential generating filament, for example, at least a part of the surface in the long axis direction and/or the circumferential direction of the filament.

For example, as schematically shown in the cross-sectional view of fig. 4, a dielectric 100 may be provided around the potential generating filament (or piezoelectric fiber) 10.

In the yarn of the present invention, the "dielectric" is an arbitrary composition, and is not an essential composition of the invention.

In the present invention, the "dielectric" refers to a substance containing a material or a substance having dielectricity (property of being electrically polarized by an electric field) and/or conductivity (property of passing electricity), and may store an electric charge on the surface thereof, for example.

In a cross-sectional view or a radial cross-sectional view of the yarn or potential generating filament of the present invention, for example, the potential generating filament, a "dielectric" is provided on the surface of the potential generating filament, whereby the relative dielectric constant of the yarn of the present invention can be adjusted to "about 4.5 or less", for example, the relative dielectric constant can be more appropriately adjusted to a range of "about 1 to about 4.5". For example, by decreasing the relative permittivity to, for example, approximately 1, an electric field having a larger electric field strength (for example, 0.1V/μm or more) can be formed. In other words, at least a part of the yarn or the potential generating filament of the present invention may be covered with a dielectric so that the relative dielectric constant of the yarn becomes about 1 to about 4.5.

The dielectric may be present in the longitudinal direction and the circumferential direction of the potential generating filament, for example, or may be completely covered with the potential generating filament or partially covered with the potential generating filament.

Therefore, the dielectric may be provided entirely or partially in the longitudinal direction of the potential generating filament. The dielectric may be provided entirely or partially in the circumferential direction of the potential generating filament.

The thickness of the dielectric may be uniform or non-uniform (see, for example, fig. 4). The thickness of the dielectric may be greater or less than the diameter of the fibers of the potential generating filaments. The thickness of the dielectric is preferably smaller than the fiber diameter of the potential generating filaments (see fig. 4).

In a cross-sectional view or a radial cross-section of the surface of the yarn or potential generating filament of the invention, such as a potential generating filament, the dielectric may be provided as a layer over at least a portion of the surface of the yarn or potential generating filament of the invention. The dielectric may be present between the plurality of potential generating filaments, in which case there may be a portion between the plurality of potential generating filaments where the dielectric is not present. Further, bubbles and voids may be present in the dielectric.

The dielectric is not particularly limited as long as it contains a material or substance having dielectric properties, conductivity, and the like. As the dielectric substance, a dielectric material (for example, an oil agent, an antistatic agent, or the like) which is known to be used mainly as a surface treatment agent (or a fiber treatment agent) in the fiber industry can be used.

In the yarn of the present invention, the dielectric preferably contains an oil agent. As the finish, a finish that can be used as a surface treatment agent (or fiber treatment agent) that can be used in the production of the potential generating filaments, or the like can be used. In addition, an oil agent that can be used as a surface treatment agent (or fiber treatment agent) that can be used in a process for producing a fabric (for example, knitting, weaving, or the like), or an oil agent that can be used as a surface treatment agent (or fiber treatment agent) that can be used in a refining process, may be used. Here, the filament production step, the cloth production step, and the purification step are given as typical examples, but not limited to these steps. As the finish, a surface treatment agent (or fiber treatment agent) such as a finish which can be used for reducing friction of the potential generating filaments is particularly preferably used.

Examples of the oil agent include Delion series manufactured by bamboos oil and fat company, Marposol series manufactured by songban oil and fat pharmaceutical company, Marposize series, and Partex series manufactured by spherulite oil chemical industry.

The finish may be present entirely along the potential-generating filaments, or may be present at least partially. After the potential generating filaments are processed into yarns, a part of the oil agent can be detached from the potential generating filaments by washing.

The dielectric substance used for reducing the friction of the potential generating filaments may be a surfactant such as a detergent or a softener that can be used for cleaning.

Examples of the detergent include Attack series manufactured by Kao corporation, Top series manufactured by Shiwang corporation, Procter & Gamble Japan Co., and Ariel series manufactured by Ltd.

Examples of the softening agent include Humming series manufactured by kao corporation, Soflan series manufactured by lion king corporation, Procter & Gamble Japan co.

The dielectric may have conductivity (by the property of electricity), and in this case, the dielectric preferably contains an antistatic agent. As the antistatic agent, an antistatic agent or the like that can be used as a surface treatment agent (or a fiber treatment agent) that can be used in the production of a potential generating filament can be used. As antistatic agents, particular preference is given to using loose antistatic agents which can be used to reduce the potential to give filaments.

By containing at least one selected from a surface treatment agent (or a fiber treatment agent) such as an oil agent or an antistatic agent, a detergent, a softener, and the like as a dielectric, a relative dielectric constant adjusted in a range of about 1.0 to about 4.5 can be imparted to the yarn.

Examples of the antistatic agent include Capron series, Nicepole series, and Dateron series, manufactured by Nikkiso chemical Co., Ltd. Among them, preferred is the Nicepole series manufactured by Nicepol chemical company, and preferred is an antistatic agent comprising an ester polymer such as a polyester polymer, particularly a PEG-modified polyester polymer (for example, Nicepole PR-99). By using such an antistatic agent, it is possible to impart a relative dielectric constant adjusted in the range of about 1.0 to about 4.5 to the yarn.

As the antistatic agent, a surface treatment agent (or a fiber treatment agent) that can impart an antistatic effect, water absorption, SR property (soil release property), and the like can be used. Examples of such antistatic agents include SR processing agents and water-absorbing processing agents (for example, SR-1800 containing polyester polymers) manufactured by kokusu oil & fat company; QUEENSTAT (クインスタット) series (for example, QUEENSTAT NW-E conc which comprises a polyurethane polymer, particularly a crosslinkable hydrophilic polyurethane polymer and can impart water-absorbing SR properties and an antistatic effect) manufactured by Kotani Chemical Industry Co., Ltd. By using such an antistatic agent, it is possible to impart a relative dielectric constant adjusted in the range of about 1.0 to about 4.5 to the yarn.

The antistatic agent may be present integrally along the surface of the potential generating filament, for example, in the direction of the long axis and/or the circumferential direction of the potential generating filament, or may be present at least in part. In addition, after the potential generating filaments are processed into yarns, a part of the antistatic agent can be detached from the potential generating filaments by washing.

In the yarn of the invention, the dielectric may be a "metal oxide". As the metal oxide, a metal oxide having conductivity (property of passing electricity) is preferably used. For example, at least 1 kind of metal oxide selected from titanium oxide, tungsten oxide, zinc oxide, zirconium oxide, niobium oxide, antimony oxide, tin oxide, indium oxide, cerium oxide, aluminum oxide, silicon oxide, magnesium oxide, yttrium oxide, ytterbium oxide, and tantalum oxide, or a composite oxide thereof may be used.

The metal oxide may be present entirely along the surface of the potential generating filament, for example, in the direction of the long axis and/or the circumferential direction of the potential generating filament, or may be present at least partially.

By using such a metal oxide, a relative dielectric constant adjusted to be about 4.5 or less, preferably in the range of about 3.0 to about 4.0, can be imparted to the yarn.

The dielectric preferably comprises titanium oxide (TiO) ₂ ) The metal oxide is because it exhibits conductivity and antibacterial properties due to photocatalytic action.

If the relative permittivity can be achieved, the amount of the surface treatment agent (or fiber treatment agent) such as an oil agent or an antistatic agent, a detergent, a softener, a metal oxide, or the like to be attached to the potential generating filaments is not particularly limited.

In the case of a surface treatment agent (or fiber treatment agent) such as an oil agent or an antistatic agent, a detergent, a softener, or the like, the amount of adhesion to the potential generating filaments is, for example, 1 to 20% by weight, preferably 1 to 15% by weight, and more preferably 4 to 15% by weight, based on 100% by weight of the potential generating filaments.

In the case of the metal oxide, the amount of adhesion to the potential generating filament is, for example, 0.1 to 5% by weight, preferably 0.1 to 1% by weight, and more preferably 0.1 to 0.5% by weight, relative to 100% by weight of the potential generating filament.

Further, the surface treatment agent (or fiber treatment agent) such as the above-mentioned oil agent or antistatic agent, detergent, softener, metal oxide, and the like may not be present around the potential generating filaments. That is, the potential generating filaments, and further the yarn of the present invention, may not contain a surface treatment agent or the like. In this case, air that can be present between the potential generating filaments or between the interstices and/or around the filaments can function as a dielectric. Therefore, in this case, the dielectric includes air or an air layer.

When the surface treatment agent (or fiber treatment agent) such as the above-mentioned oil agent, antistatic agent, etc., detergent, softener, metal oxide, etc. is not present around the potential generating filaments, in other words, the untreated or unprocessed potential generating filaments may have a relative dielectric constant adjusted, for example, to a range of about 1.0 to about 3.0, preferably about 1.0 to about 2.6, more preferably about 1.0 to about 2.0.

In the present invention, when the surface treatment agent (or fiber treatment agent) such as the above-mentioned oil agent or antistatic agent, detergent, softening agent, metal oxide, or the like is present around the filament without generating a potential, in other words, when only an air layer is present around the filament, the presence of an extremely small amount of components that are inevitably or accidentally mixed in during the production of the yarn or filament can be allowed.

The thickness of the dielectric (or the spacing of the potential generating filaments) is from about 0 μm to about 10 μm, preferably from about 0.5 μm to about 10 μm, more preferably from about 2.0 μm to about 10 μm, and typically around 5 μm. Within such a range, the yarn of the present invention can preferably have a relative permittivity value of "about 4.5 or less" which is an object described in detail below, and can more reliably exhibit antibacterial properties.

In addition, in the yarn of the present invention, the "dielectric" may have a relative dielectric constant (e) of about 1.0 to about 5.0, preferably a relative dielectric constant (e) of about 2.0 to about 5.0, more preferably about 3.0 to about 5.0, still more preferably about 3.5 to about 5.0, and particularly preferably about 4.0 to about 5.0 (fig. 5). Within such a range, the yarn of the present invention can preferably have a dielectric constant value of "about 4.5 or less" which is an object to be described in detail below, and can more reliably exhibit antibacterial properties.

The relative dielectric constant of the yarn can be calculated, for example, as follows: the yarn was held between 1 set of electrodes such as an LCR meter, a potential was applied between 2 electrodes, the capacitance was calculated from the amount of charge generated in the electrodes and the applied potential, and the relative dielectric constant of the yarn was calculated from the capacitance, the area of the electrodes, and the inter-electrode distance.

[ characteristics of yarn ]

The yarn of the invention has the following characteristics: the dielectric constant is about 4.5 or less, for example, about 1.0 to about 4.5.

The lower limit of the relative dielectric constant may be about 1.5, or about 2.0, or about 2.5, or about 2.6, or about 3.0, or about 3.5, or about 4.0.

The upper limit of the relative dielectric constant may be about 4.0, about 3.5, about 3.0, about 2.6, about 2.5, about 2.0, or about 1.5.

The upper and lower limits of the relative permittivity may be combined as necessary.

According to such physical property values, the antibacterial properties can be more reliably obtained in the present invention. The inventors of the present application have first established that the antibacterial properties can be obtained more reliably based on the physical properties of the yarn such as the relative permittivity. The mechanism thereof, and the background of the research for finally finding such physical property values and antibacterial properties are described in detail below.

(mechanism)

As a result of intensive studies by the present inventors, for example, when the yarn is observed in a cross-sectional view or a radial cross-sectional view, it has been found that in the past, the strength of an electric field formed in the yarn is reduced due to a state where spaces and/or gaps between filaments are generated by a potential, in particular, due to physical properties such as a dielectric constant of a dielectric substance (including an air layer) existing between filaments and/or a dielectric constant of the yarn itself, and thus, for example, a desired or constant (level) antibacterial property may not be obtained.

As shown in the preliminary tests (fig. 8) of the following examples, the inventors of the present invention found that the value of "voltage (or potential)" has a greater influence on the antibacterial action than the value of current.

Here, the target bacteria are simply described as bacteria (bacteria) and fungi (fungus), and in particular, the fungi are composed of a long and thin elongated hypha (hypa) and a cell (spore) having a substantially circular shape. In addition, it is known that: the spores proliferate by germination, float in the air, etc., and attach to the parasite to form hyphae, thereby performing sexual and asexual reproduction ("new dermatology", 2 nd edition, macrography of clear water, page 469). The size of the cell contributing to such proliferation is approximately about 2 to 10 μm ("window for food hygiene", homepage of tokyo welfare and health care agency).

Next, it has been known that the growth of bacteria can be inhibited by an electric field (see, for example, Techio, Kogakunji, Songgangming, Seikou, lecture: microbiological control-science and engineering; see, for example, Kogaohao, application of high voltage plasma technology in the agricultural and food fields, J.HTSJ, Vol.51, No. 216).

In addition, it is known that: the electric potential generated by the electric field causes a current to flow through a current path formed by moisture or the like, or a circuit formed by a local microdischarge phenomenon or the like, and the bacteria are degraded by the current, whereby the growth of the bacteria can be suppressed.

As one of the mechanisms of cell membrane disruption associated with such electrical stimulation, Electroporation (Electroporation method) (mechanism based on high-voltage pulse cell Electroporation, which is the basis of gene transfer method, gengxi dao · oryza glauca, p 1595) is known.

According to the above documents, conditions for generating electroporation for disrupting cell membranes of bacteria and the like are generally cases where a potential difference (or voltage) of "about 1.0V" is applied to cells, and the present inventors considered that: for example, if the size of the cell is about 2 μm to 10 μm, if an electric field or potential with an electric field strength of about 0.1V/μm or more is generated, even if the cell has a size of about 10 μm at the maximum, a potential difference (or voltage) of about 1.0V or more can be applied, and electroporation can be generated to destroy the cell membrane or disturb the electron conduction system for life support, and cell degeneration or death or reduction can be caused.

Based on such a study, the inventors of the present application have first conducted repeated studies on the relationship between the electric field intensity (V/μm) of an electric field and the dielectric constant, for example, the dielectric constant of a dielectric which is considered to have an effect on antibacterial properties, particularly the relationship between the "relative dielectric constant (∈)" of the dielectric.

As a result, for example, as shown in the graph of fig. 5, it was found that: for example, when the value of the relative dielectric constant (e) of the dielectric material that can be provided in the piezoelectric fiber is in the range of about 1.0 to about 5.0, preferably about 3.5 to about 5.0, and more preferably about 4.0 to about 5.0, an electric field having an electric field strength of about 0.1V/μm or more can be formed when an external force, for example, a tensile force of about 0.15%, for example, a tensile strain (in other words, a tensile force in the axial direction of the fiber and a tensile stress applied to the fiber) is applied.

In FIG. 5, the values (V/. mu.m) of the electric field intensity at each filament interval (X: 0.5. mu.m, Y: 2. mu.m, Z: 5. mu.m) with respect to the relative permittivity (. epsilon.) of the dielectric material are specifically shown in the following table. The graph shown in fig. 5 merely illustrates the relationship between the relative permittivity of the dielectric and the electric field intensity.

TABLE 1

Further studies have found that the relative permittivity of the yarn also has an effect on the antibacterial properties. Further, it has been found that if the relative dielectric constant of the yarn is about 4.5 or less, preferably in the range of about 1.0 to about 4.5, an electric field or potential having an electric field strength of about 0.1V/μm or more can be formed when external energy such as external force, for example, external energy such as tensile force or tensile strain of at least 0.15% is applied.

Here, the electric field intensity can be measured by using, for example, a scanning probe microscope, a surface potentiometer, or the like.

Specifically, first, a scanning probe microscope is used to detect displacement of a probe due to an electric attraction force or a repulsive force by bringing a minute probe to which a weak voltage is applied close to an object to be measured. Next, by measuring a voltage for canceling out the electric attraction or repulsion applied to the minute probe using a surface potentiometer, a value of the surface potential or a value of the electric field intensity of the object to be measured can be obtained.

The measurement by the scanning probe microscope and the surface potentiometer can be performed by using a power microscope (for example, Model 1100TN manufactured by Trek corporation) having both functions.

Thus, if the "relative permittivity" as the physical property of the yarn is a value of "about 4.5 or less", an electric field having an electric field strength of "about 0.1V/μm or more" can be formed. Further, in fungi having a cell size of about 2 μm to 10 μm, if such an electric field is formed, even if the cell size is 10 μm which is the largest, a potential difference of 1.0V or more can be applied, and for example, cell membranes can be destroyed by electroporation, whereby the fungi can be degraded, killed, or reduced. In other words, the antibacterial activity can be more reliably exhibited.

Further, if the value of the "relative permittivity" of the yarn is a value of about 1.0 or more (desirably 4.5 or less), an electric field or a potential having an electric field strength of about 0.1V/μm or more can be formed as described above, which is preferable.

The yarn of the present invention typically has a filament spacing (or dielectric thickness) of about 5 μm, and the "relative dielectric constant" of the yarn is about 1.0 to about 2.6, or about 2.0 to about 2.6. In this case, an electric field having an electric field strength of about 0.1V/. mu.m or more can be formed, which is preferable.

As described above, the yarn of the present invention has a "relative permittivity" of "about 4.5 or less" as an inherent physical property and a value (physical property value) thereof which have been found for the first time by the present inventors, and can form an electric field or a potential having an electric field strength of "about 0.1V/μm or more". By the direct action of such an electric field or electric potential, the cell membrane of the bacteria and the electron conduction system for maintaining the life of the bacteria are disturbed, and the generation and proliferation of the bacteria are suppressed. Further, the bacteria may be attenuated or reduced or killed.

Accordingly, in the present invention, the term "antimicrobial properties" means that the yarn of the present invention can form an electric field or potential having an electric field strength of about 0.1V/μm or more, thereby at least inhibiting or preventing the generation or proliferation of bacteria. The term "antibacterial property" used in the present invention may include the deterioration of bacteria, the reduction of bacteria, and death.

In some cases, the antibacterial effect is indirectly exerted by an active oxygen species in which oxygen contained in moisture changes due to an electric potential or an electric field or current generated by the yarn of the present invention, or by a radical species or other antibacterial chemical species (amine derivative or the like) generated by an interaction or a catalytic action of an additive material contained in the fiber. In addition, there are also cases where oxygen radicals are generated in the cells of bacteria by the formation of a stress environment due to the potential generated by the yarn of the present invention or the presence of an electric field or current, and there are cases where such oxygen radicals indirectly exert antibacterial properties. Examples of the radical include superoxide anion radical (active oxygen) and hydroxyl radical.

The deterioration, death or reduction of bacteria caused by the action of such reactive oxygen species, radical species, antibacterial chemical species, oxygen radicals and the like are included as the antibacterial effect in the definition of "antibacterial property" above.

In the present invention, "bacteria" is a concept as follows: the term "antibacterial" refers to any kind of fungi such as bacteria and fungi, and includes microorganisms such as mites and fleas, and/or viruses, as long as the "antibacterial property" is obtained. The bacteria are preferably targeted to "fungi (fungus)". Fungi are a kind of eukaryotic microorganisms having a cell wall, and are organisms that parasitize any organism or exist in nature in the form of a cell because they do not perform photosynthesis. Among the fungi, dermatophytes are preferably targeted, and trichophyton is particularly preferred.

The yarn of the present invention is also sometimes referred to as "antimicrobial yarn" because it has "antimicrobial properties" against bacteria.

(other characteristics)

The yarn (or the antibacterial yarn) of the present invention may further have the following physical properties (impedance, resistivity, etc.) and values thereof (physical properties). The following physical properties and physical property values are preferable because the antibacterial property can be obtained more reliably. The following physical properties and physical property values were first found by intensive studies by the present inventors.

(impedance)

In the yarn of the invention, the impedance is about 4.0X 10 ⁶ Omega m or more, preferably about 4.0X 10 ⁶ Omega m to about 1.8X 10 ⁷ Omega m, typically 7.0X 10 ⁶ And omega m is about.

When the yarn of the present invention has an impedance within the above range, an electric field or potential having an electric field strength of about 0.1V/μm or more can be formed, and the antimicrobial properties can be more reliably achieved.

In the present invention, "impedance" means impedance Z per unit volume. For example, as schematically shown in fig. 6, the impedance Z is measured by sandwiching the yarn between 2 measurement electrodes and connecting the 2 measurement electrodes to an LCR meter (or an impedance measuring device).

The method of measuring the impedance Z is not limited to the method shown in fig. 6.

Here, the yarn of the present invention is considered as an ideal dielectric, and when the capacitance is C and the frequency is 1kHz, the impedance Z per unit volume of the yarn of the present invention can be expressed by the following equation.

Z＝1/C×1.6×10 ^-4 Ω

(wherein C represents a capacitor)

The capacitance C is directly proportional to the "relative permittivity" of the yarn of the invention, and therefore the impedance Z is inversely proportional to the "relative permittivity" of the yarn of the invention.

Therefore, "4.0 × 10" as the lower limit value of the impedance Z ⁶ Ω m "may correspond to an upper limit of the relative dielectric constant of the yarn of the invention" 4.5 ". In addition, "1.8 × 10" as the upper limit value of the impedance Z ⁷ Ω m "may correspond to a lower limit value of" 1.0 "of the relative dielectric constant of the yarn of the invention.

In this way, the value of the impedance of the yarn can be converted into the relative dielectric constant of the yarn.

The yarn of the present invention has a typical impedance value of "7.0 × 10 ⁶ Ω m "may correspond to" 2.6 "which is a typical value of the" relative dielectric constant "of the yarn of the invention.

(resistivity)

In the yarn of the invention, the resistivity is about 1.4X 10 ⁴ Omega m or more, preferably about 1.4X 10 ⁴ Omega m to about 2.3X 10 ¹⁵ Ωm。

If the specific resistance of the yarn of the present invention is within the above range, an electric field or potential having an electric field strength of about 0.1V/μm or more can be formed, and the antibacterial properties can be more reliably achieved.

Here, refer to fig. 7. Fig. 7 shows the relationship between "interval d (μm) between potential generating filaments" (hereinafter, also referred to as "filament interval d") and "electric field intensity (V/μm)" in the yarn of the present invention. "filament spacing d" means the shortest distance (μm) between the surfaces of 2 potential generating filaments that are adjacent to each other. The filament spacing d may correspond to the thickness of the "dielectric" that may be present between the filaments.

Typically, the resistivity of the "dielectric" is less than the resistivity of the "potential generating filament" (e.g., the resistivity of an antistatic agent: about 1X 10) ³ Ω m). As the "filament spacing d" increases, the resistivity of the yarn of the invention tends to decrease.

When the yarn of the present invention is regarded as an ideal resistor, for example, as shown in fig. 7, when the "filament spacing d" is "5 μm" (the filament spacing (or the thickness of the dielectric) of the yarn of the present invention is typically about 5 μm), "the electric field strength" is "about 0.1V/μm", and the "resistivity" of the yarn of the present invention in this case is "about 1.4 × 10 ⁴ Ω m ", may correspond to the above lower limit value (about 1.4 × 10) ⁴ Ω m). In addition, in the case where the "filament interval d" is "0 μm", the "specific resistance" of the yarn of the present invention is the maximum, and its value is "about 2.3X 10 ¹⁵ Ω m ", may correspond to the above upper limit value (about 2.3 × 10) ¹⁵ Ωm)。

In this way, the value of the resistivity of the yarn can be calculated from the electric field strength of the yarn.

Here, more specifically, in fig. 7, the value (V/μm) of the electric field intensity at the filament interval d (μm) with respect to the relative permittivity (∈) of the dielectric is as shown in the following table.

TABLE 2

In the yarn of the present invention, the electrical resistivity can be measured by, for example, an insulation resistance meter.

In the yarn (or antimicrobial yarn) of the present invention, the physical properties and values thereof (physical properties) that can more reliably obtain antimicrobial properties are not limited to the above "relative permittivity", "impedance" and "specific resistance".

[ use of yarn ]

The yarn of the present invention is a yarn having a potential generating filament (or a potential generating fiber, a charge generating fiber, or an electric field forming fiber) and a fiber capable of generating a potential by generating a charge by an energy from the outside (for example, an external energy such as a tensile force or a tensile strain given by at least 0.15%), and forming an electric field, and therefore, an electric field or a potential can be formed in the vicinity of the yarn, or an electric field can be generated in the case of an object having a predetermined potential (including a ground potential) such as between yarns or in the vicinity of a human body. As described above, the antibacterial activity can be directly exerted by such a potential or electric field.

In addition, the yarn of the present invention can flow an electric current when it is brought close to an object having a predetermined potential, such as another adjacent fiber or a human body, through moisture such as sweat. The antibacterial activity may be exerted by the current.

Therefore, when the yarn of the present invention is applied to an article that can be used near an object having a predetermined potential such as a human body, for example, the yarn can exhibit the antibacterial property as described above by the action of the generated potential or electric field or current, particularly, the direct action of the potential or electric field.

The article or product to which the yarn of the present invention can be applied is not particularly limited, and examples thereof include medical articles (all types) such as clothing (all types), shoes (all types), and masks. More specifically, the following applications and the like are considered.

Examples thereof include: clothing items, in particular underwear (particularly socks), towels, footwear items, insoles such as shoes and boots, sports clothing items, hats, bedding items (including quilts, mattresses, sheets, pillows, pillow cases, and the like), toothbrushes, dental floss, various filters (water purifiers, filters for air conditioners, air purifiers, and the like), plush toys, pet-related goods (mats for pets, pet clothes, linings for pet clothes), various pad products (feet, hands, toilets, and the like), window cloths, kitchen supplies (sponges, and the like), seats (seats for automobiles, trains, or airplanes and the like), cushioning materials for helmets for motorcycles and their outer coverings, sofas, medical supply items, bandages, masks, sutures, clothing for doctors and patients, protectors, sanitary products, sporting goods (linings for clothing and gloves, linings for clothing, linings for doctors, and gloves, linings for doctors, and patients), cushioning materials for motorcycles and their outer coverings, Or guard arms used in a wrestling), or packaging materials, etc.

In clothing, particularly socks (or protectors), stretch and contract along joints inevitably due to walking or other movements, and therefore, the yarn of the present invention generates electric charges or electric potentials at a high frequency. In addition, although socks absorb moisture such as sweat and become a hotbed for bacteria growth, the yarn of the present invention can suppress bacteria growth, and therefore, the yarn can produce a remarkable effect as an antibacterial application for deodorization.

The yarn of the present invention is suitable for all applications requiring antibacterial properties, and the use thereof is not limited to the above applications.

(cloth)

For use in the above applications, the yarn of the present invention may be processed into, for example, a cloth. Therefore, such a fabric is made of the yarn of the present invention, and can be used for the above-mentioned applications as the above-mentioned "antibacterial fabric" having antibacterial properties. The fabric of the present invention includes woven fabric, knitted fabric, nonwoven fabric and the like. They can be produced by appropriately processing the yarn of the present invention by a method known in the art, or the like.

The yarn and the fabric of the present invention will be described in further detail below with reference to examples.

Examples

< preliminary test for confirming antibacterial action by Electrical stimulation >

Preliminary tests for confirming the antibacterial action by the electric stimulation were performed based on the following steps (1) to (4).

(1) As the bacteria, trichophyton (fungi) was used, and a trichophyton suspension was prepared by suspending the trichophyton in a sprouting tube state in pure water.

(2) A voltage was applied to the suspension of Trichophyton mentagrophytes under the following conditions.

(3) The state of trichophyton after voltage application is shown in the photograph of [ fig. 8 ].

(4) As representative examples of the changes in the state of trichophyton before and after the application of voltage, photographs of the changes in the state of trichophyton for 20V × 5Hz and 50V × 5Hz are shown in [ fig. 9] (a) and [ fig. 9] (b), respectively.

Inter-electrode distance

50μm

Voltage of

Condition a: 10V

Condition B: 20V

Condition C: 30V

Condition D: 40V

Condition E: 50V

Frequency of

1Hz

5Hz

10Hz

Number of measurements

n＝3

(results)

The voltage was changed from 10V to 50V every 10V to increase the voltage value (conditions a to E). As a result, it was found that the following cases exist: as the voltage is increased, trichophyton deforms and the flow of matrix stops. FIG. 9(a) and FIG. 9(b) are representative photographs of the deformation of Trichophyton before and after voltage application, and the deformation of spores and hyphae was confirmed, respectively. In particular, under the voltage conditions D and E, the flow of trichophyton prototypes was confirmed to be stopped.

On the other hand, it is known that the following may occur: even if the frequency is changed to 1Hz, 5Hz, or 10Hz, the current value is increased, and the flow of trichophyton prototypes is not stopped.

From the above, it can be seen that: the value of the voltage is more relevant than the value of the current for the antibacterial action.

In addition, it can be seen that: the size of trichophyton spores used in the preliminary test is about 5 μm as shown in the photograph of fig. 10, and when a voltage with an electric field strength of about 0.2V/μm or more is applied, a voltage of about 1.0V or more is applied from one end to the other end of the cells, and trichophyton dies or decreases.

From the above, it can be seen that: since the size of the cell of bacteria, particularly fungi, is about 2 to 10 μm ("window for food hygiene", homepage of tokyo welfare health administration), if a voltage of about 0.1V/μm or more is applied based on the above results, a voltage of about 1.0V or more can be applied to the cell corresponding to the size of 10 μm at maximum, and such bacteria can be killed or reduced.

The preliminary tests are merely examples, and are not intended to limit the present invention.

(example 1)

Preparation of yarn A

As a piezoelectric material, a yarn A (untwisted yarn) comprising potential generating filaments (number of filaments: 24) containing poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, and crystallinity measured by ultraX 18 manufactured by Rigaku Corporation: 42 to 44%). The potential generating filament contained in yarn a contains an oil agent as a dielectric around it. Note that: the finish is washed after the production of the yarn, and a part of the finish is peeled off from the potential by the filament.

Determination of the relative permittivity of yarn A

The relative dielectric constant of yarn a can be determined as follows: the yarn a is passed between the parallel plate capacitors to measure the capacitance, the capacitance of the yarn a is calculated from the difference from the capacitance when the yarn a is not passed, the dielectric constant of the yarn a is determined using the value and the yarn capacitance, and further the dielectric constant of the vacuum is used, based on the formula: the relative dielectric constant of yarn a ═ dielectric constant of yarn a ]/[ dielectric constant of vacuum ], was determined by calculation; as a result, it was found that the relative dielectric constant of the yarn A was about 1.4 (measurement temperature: room temperature (25 ℃ C.)).

Measurement of electric field intensity of electric field formed by yarn A

Since the yarn a contains PLLA (optical purity (L type): 99% or more and has a crystallinity of 42 to 44%), it is known that an electric field or an electric potential is generated by applying energy from the outside such as tensile strain of at least 0.15%. Since the relative dielectric constant of the yarn a was 1.4, it was found that the electric field formed by the yarn a had an electric field strength of more than about 0.1V/μm as a result of measurement using an electric microscope (for example, Model 1100TN manufactured by Trek corporation) including a scanning probe, a surface potentiometer, and the like.

The electric field intensity is measured as follows: first, a scanning probe is used to detect the displacement of the probe due to the electric attraction or repulsion by bringing a minute probe to which a weak voltage is applied close to the yarn a, and then a surface potentiometer is used to measure a voltage for canceling out the electric attraction or repulsion applied to the minute probe, thereby measuring the value of the electric field intensity of the yarn a.

Antibacterial property

From the above, it can be seen that: the yarn a has an electric field strength of more than about 0.1V/μm, and thus exhibits a sufficient antibacterial activity against trichophyton, for example, about 10 μm.

(example 2)

Preparation of yarn B

As a piezoelectric material, a yarn B (untwisted yarn) comprising potential generating filaments (number of filaments: 24) containing poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, crystallinity measured by ultraX 18 manufactured by Rigaku Corporation: 42 to 44%). The potential generating filaments comprised by yarn B comprise an antistatic agent as a dielectric around them. In addition, it can be seen that: the antistatic agent is washed after the production of the yarn, so that a part of the antistatic agent is peeled off from the potential-generating filaments.

Determination of the relative permittivity of yarn B

The relative permittivity of the yarn B was measured in the same manner as that of the yarn A, and was found to be about 1.4 (measurement temperature: room temperature (25 ℃ C.)).

Measurement of electric field intensity of electric field formed by yarn B

Since the yarn B contains PLLA (optical purity (L type): 99% or more and has a crystallinity of 42 to 44%), it is known that an electric field or an electric potential is generated by applying energy from the outside such as tensile strain of at least 0.15%. Since the relative permittivity of the yarn B was about 1.4, the electric field formed by the yarn B was measured in the same manner as the yarn a, and it was found that the electric field intensity was greater than about 0.1V/μm.

Antibacterial property

From the above, it can be seen that: the yarn B has an electric field strength of more than about 0.1V/μm, and thus exhibits a sufficient antibacterial activity against trichophyton of about 10 μm, for example.

(example 3)

Preparation of yarn C

As a piezoelectric material, a yarn C (untwisted yarn) comprising potential generating filaments (number of filaments: 24) containing poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, and crystallinity measured by ultraX 18 manufactured by Rigaku Corporation: 42 to 44%). Yarn C contains a potential generating filament completely free of surface treatment agent, and around it, only an air layer is present as a dielectric.

Determination of the relative permittivity of yarn C

The relative permittivity of the yarn C was measured in the same manner as that of the yarn A, and was found to be about 1.1 (measurement temperature: room temperature (25 ℃ C.)).

Measurement of the electric field intensity of the electric field formed by the yarn C

Since the yarn C contains PLLA (optical purity (L-type): 99% or more and crystallinity: 42 to 44%), it is known that an electric field or potential is generated by applying energy from the outside such as tensile strain of at least 0.15%. Since the yarn C had a relative permittivity of about 1.1, the electric field generated by the yarn C was measured in the same manner as the yarn a, and it was found that the electric field intensity was greater than about 0.1V/μm.

Antibacterial property

From the above, it can be seen that: the yarn C has an electric field strength of more than about 0.1V/μm, and thus exhibits a sufficient antibacterial property against trichophyton, for example, about 10 μm.

(example 4)

Preparation of yarn D

As a piezoelectric material, a yarn D (untwisted yarn, degreased) composed of potential generating filaments (number of filaments: 24) composed of poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, and crystallinity measured by ultraX 18 manufactured by Rigaku Corporation was 42 to 44%).

Determination of the relative permittivity of the yarn bundle of yarn D

The yarn D was arranged in the lateral direction on a bobbin having a diameter of 45mm by using a yarn winder manufactured by village, and the yarn D was wound on the bobbin (rotation speed: 60rpm, 1 minute) by a thread guide so that the yarn D did not overlap in the thickness direction (see fig. 11 a).

The yarn D was cut out from the bobbin by cutting the yarn D in the axial direction of the bobbin, and a yarn bundle sample (yarn D) having a width of about 1cm was obtained (see fig. 11B). Both ends of the yarn bundle sample in the upper and lower directions in the longitudinal direction were fixed at the time of cutting.

A yarn sample (yarn D) was set on a jig (vise) and fixed with Kapton (registered trademark) tape (fig. 12(a) is referred to (the photograph is merely an example showing a measuring method, and the yarn included in the yarn bundle sample is different from the yarn D)).

A yarn bundle sample (yarn D) was placed in a superposed manner (thickness: about 50 μm) between 2 circular measurement electrodes of an LCR Meter (Precision LCR Meter (model E4980A) manufactured by Agilent) connected to a fixing device (model 16451B manufactured by Agilent corporation), and the yarn bundle sample was sandwiched and fixed between the 2 measurement electrodes (see FIG. 12B) (the photograph is merely an example of a measurement method, and the yarn included in the yarn bundle sample is different from the yarn D)).

Here, the relationship between the measurement electrode of the LCR meter and the yarn bundle sample is shown in FIG. 13. In the case of the yarn bundle sample shown in the schematic diagram, since the yarns D are sandwiched between the measurement electrodes and are adjacent to each other, it is assumed that there is no gap between the yarns D.

The sum of the areas S1 and S2 shown in fig. 13 was set to 4 times, and this was calculated as the area of the yarn bundle sample (hereinafter referred to as "sample area").

The relative dielectric constant of the yarn D was measured in such a sample area by an LCR meter, and as a result, the value was about 2.1 (temperature: room temperature (25 ℃ C.), frequency: 1 kHz). Details of the measurement are shown in table 3 below.

(example 5)

Preparation of yarn E

As a piezoelectric material, a yarn E (untwisted yarn, degreased yarn) comprising a potential generating filament (number of filaments: 24) made of poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, and crystallinity (42-44%) measured by ultraX 18 manufactured by Rigaku Corporation).

Determination of the relative permittivity of the yarn bundle of yarn E

The relative permittivity of the yarn E was measured by an LCR meter in the same manner as the yarn D of example 4, and the value of the relative permittivity was about 1.9. Details of the measurement are shown in table 3 below.

(example 6)

Preparation of yarn F

As a piezoelectric material, a yarn (untwisted yarn) comprising a potential generating filament (number of filaments: 24) of poly-L-lactic acid (PLLA) was prepared (optical purity (L type) measured by High Performance Liquid Chromatography (HPLC) was 99% or more, crystallinity measured by ultraX 18 manufactured by Rigaku Corporation: 42 to 44%).

About 0.1mL of a surface treatment agent (Nicepole PR-99 (Nicepole series manufactured by Rihua chemical Co., Ltd.) and an antistatic agent comprising a PEG-modified polyester polymer) was applied to the yarn and dried to prepare a yarn F (untwisted yarn) (weight before application: 0.207g, dried weight after application: 0.219g, adhesion: 0.012g, adhesion: 5.4 wt%).

Determination of the relative permittivity of the yarn bundle of yarn F

A yarn bundle sample of the yarn F was prepared in the same manner as in example 4 (see fig. 11).

A yarn bundle (yarn F) was set on a jig (vise) and fixed with Kapton (registered trademark) tape (fig. 12(a) is referred to (the photograph is merely an example showing a measurement method, and the yarn included in the yarn bundle sample is different from the yarn F)).

In the same manner as in example 4, a yarn bundle sample (yarn F) was placed in a superposed manner (thickness: about 50 μm) between 2 circular measurement electrodes of an LCR Meter (Precision LCR Meter (model: E4980A) manufactured by Agilent corporation) connected to a fixing device (model: 16451B manufactured by Agilent corporation), and the yarn bundle sample was sandwiched between the 2 measurement electrodes to fix the sample (see fig. 12(B) (the photograph is merely an example showing a measurement method, and the yarn included in the yarn bundle sample is different from the yarn F)).

In the case of this yarn bundle sample, the yarn F was coated with the surface treatment agent, and therefore, filaments included in the yarn were gathered, and a space was generated between the yarn F and the yarn F.

In this case, for example, the area of the space is subtracted from a value obtained by multiplying the sum of the areas S1 and S2 shown in fig. 13 by 4 (in other words, the value of the area in an ideal state), and the result is calculated as the sample area. The area of the space is calculated as follows: the distance between the yarns F and F is actually measured, preferably calculated as an average of the total of the gaps, and calculated by integrating the distances in the width direction (the electrode diameter direction) of a yarn bundle sample (see fig. 13) having a width of 1cm and arranged on the measuring electrode.

The relative dielectric constant of the yarn F was measured by an LCR meter in such a sample area, and as a result, the value was about 4.5 (temperature: room temperature (25 ℃ C.), frequency: 1 kHz). Details of the measurement are shown in table 4 below.

(example 7)

Preparation of yarn G

About 0.1mL of a surface treatment agent (SR-1800 (SR processing agent/water absorbing processing agent series manufactured by kokusu oil & fat corporation), water absorbing property/SR property (stain removing property or stain proofing property) containing a polyester polymer, and a surface treatment agent capable of imparting an antistatic effect) was applied to the yarn, and the yarn was dried to prepare a yarn G (untwisted yarn) (weight before application: 0.203G, dried weight after application: 0.213G, adhesion: 0.010G, adhesion: 4.7 wt%).

Determination of relative dielectric constant of yarn bundle of yarn G

The relative permittivity of the yarn G was measured by an LCR meter in the same manner as the yarn F of example 6, and as a result, the value of the relative permittivity was about 4.5. Details of the measurement are shown in table 4 below.

(example 8)

Preparation of the yarn H

The yarn was coated with about 0.1mL of a surface treatment agent (QUEENSTAT) NW-E conc (Kotani Chemical Industry co., ltd. QUEENSTAT series), water-absorbing property SR property (stain-removing property or stain-proofing property) containing a crosslinkable hydrophilic polyurethane polymer, or a surface treatment agent capable of imparting an antistatic effect, and dried to prepare a yarn H (untwisted yarn) (weight before coating: 0.205g, dry weight after coating: 0.234g, attachment weight: 0.029g, attachment amount: 12 wt%).

Determination of relative permittivity of yarn bundle of yarn H

The relative permittivity of the yarn H was measured by an LCR meter in the same manner as the yarn F of example 6, and the value of the relative permittivity was about 4.4. Details of the measurement are shown in table 4 below.

(example 9)

Preparation of yarn I

The yarn was coated with a liquid containing about 0.1mL of metal oxide (titanium oxide (TiO) ₂ ) Spray liquid (TRUSCO (トラスコ) photocatalyst TiO manufactured by Zhongshan corporation ₂ Antibacterial/deodorant spray)), and dried to prepare a yarn I (untwisted yarn) (weight before coating: 0.206g, dry weight after coating: 0.207g, adhesion weight: 0.001g, adhesion amount: 0.48 wt%).

Determination of the relative permittivity of the yarn bundles of yarn I

The relative dielectric constant of the yarn I was measured by an LCR meter in the same manner as the yarn F of example 6, and the value of the relative dielectric constant was about 3.3. Details of the measurement are shown in table 5 below.

(example 10)

Preparation of yarn J

The yarn was coated with a liquid containing about 0.1mL of metal oxide (titanium oxide (TiO) ₂ ) Spray liquid (TRUSCO (トラスコ) photocatalyst TiO manufactured by Zhongshan corporation ₂ Antibacterial/deodorant spray)), and dried, thereby preparing a yarn J (untwisted yarn) (weight before coating: 0.213g, dried after coatingWeight: 0.213g, adhesion weight: less than 0.001g, adhesion amount: less than 0.47 wt%).

Determination of relative dielectric constant of yarn bundle of yarn J

The relative dielectric constant of the yarn J was measured by an LCR meter in the same manner as the yarn F of example 6, and the value of the relative dielectric constant was about 3.5. Details of the measurement are shown in table 5 below.

TABLE 3

Yarn bundle sample	Example 4	Example 5
			Yarn	D (untwisted yarn)	E (untwisted yarn)
Thickness [ m ]]	5.00E-05	5.00E-05
			Cp[F]	1.69E-10	1.50E-10
Electrode area m ² ]	0.001134115	0.001134115
			Area of sample [ m ² ]	0.000438149	0.000438149
Dielectric constant of vacuum	8.85E-12	8.85E-12
			Relative dielectric constant	About 2.1	About 1.9

TABLE 4

Yarn bundle sample	Example 6	Example 7	Example 8
				Yarn	F (untwisted yarn)	G (untwisted yarn)	H (untwisted yarn)
Thickness [ m ]]	2.6E-04	2.8E-04	2.9E-04
				Cp[F]	4.39E-11	4.14E-11	3.96E-11
Electrode area m ² ]	0.001134115	0.001134115	0.001134115
				Area of sample [ m ² ]	0.000281082	0.000287416	0.000291216
Dielectric constant of vacuum	8.85E-12	8.85E-12	8.85E-12
				Relative dielectric constant	About 4.5	About 4.5	About 4.4

TABLE 5

Yarn bundle sample	Example 9	Example 10
			Yarn	1 (untwisted yarn)	J (untwisted yarn)
Thickness [ m ]]	9.0E-05	1.0E-04
			Cp[F]	1.44E-10	1.39E-10
Electrode area m ² ]	0.001134115	0.001134115
			Area of sample [ m ] ² ]	0.000438149	0.000438149
Dielectric constant of vacuum	8.85E-12	8.85E-12
			Relative dielectric constant	About 3.3	About 3.5

Measurement of electric field intensity of electric field formed by yarns D to J

Since the yarns D to J contain PLLA (optical purity (L type): 99% or more and crystallinity: 42 to 44%), they generate an electric field by applying external energy such as a stretching force or a stretching strain of at least 0.15%. Since the yarns D to J have a relative permittivity of about 4.5 or less, it is understood that the electric field generated by the yarns D to J has an electric field strength of more than about 0.1V/μm, similarly to the yarns a to C.

Antibacterial property

From the above, it can be seen that: the yarns D to J have an electric field strength of more than about 0.1V/μm and exhibit a sufficient antibacterial activity against Trichophyton mentagrophytes of about 10 μm.

It is noted that the relative dielectric constant of the yarn a of example 1 and the yarn B of example 2 was measured as a bundle of yarns in the same manner as the yarn F of example 6, and it was found that the relative dielectric constants were about 1.4, respectively, and the results were the same as those of the measurements in examples 1 and 2.

As a result of measuring the relative permittivity as a yarn bundle for the yarn C of example 3 in the same manner as for the yarn D of example 4, it was found that the relative permittivity of the yarn C was about 1.1, and the relative permittivity was consistent with the measurement result in example 3.

Comparative example 1

Since a non-piezoelectric polylactic acid (PLA) polymer (TERRAMAC (registered trademark) manufactured by yunigkok, ltd., crystallinity: 34%) has no piezoelectricity, it was found that it does not generate electric charges and does not exhibit antibacterial properties.

The above examples 1 to 10 are merely examples of the yarn of the present invention, and particularly, merely examples of the yarn of the present invention in which the relative dielectric constant, the generated potential, and the like can be adjusted, and the yarn of the present invention is not limited to the embodiments shown in the above examples. In addition, in examples 1 to 10, although there was no twist yarn, the electric field strength could be further increased by twisting (for example, 45 °), and the antibacterial property could be further improved.

Finally, the mode of the present invention is explained in the attached drawings. The present invention described above includes, but is not limited to, the following modes.

(mode 1)

A yarn having a potential generating filament or an electric field forming filament, characterized in that the yarn has a relative dielectric constant of 4.5 or less.

(mode 2)

The yarn according to mode 1, wherein the relative permittivity is 1.0 or more.

(mode 3)

The yarn according to

mode

1 or 2, wherein the yarn has an impedance of 4.0 × 10 ⁶ Omega m or more.

(mode 4)

The yarn according to mode 3, wherein the impedance is 1.8 x 10 ⁷ Omega m or less.

(mode 5)

The yarn according to any one of aspects 1 to 4, wherein the yarn has a specific resistance of 1.4 × 10 ⁴ Omega m or more.

(mode 6)

The yarn of claim 5, wherein the electrical resistivity is 2.3 x 10 ¹⁵ Omega m or less.

(mode 7)

The yarn according to any one of aspects 1 to 6, wherein the potential generating filament comprises a piezoelectric material.

(mode 8)

The yarn according to claim 7, wherein the piezoelectric material comprises poly-L-lactic acid (PLLA).

(mode 9)

The yarn according to mode 8, wherein the poly-L-lactic acid (PLLA) has a crystallinity of 35% or more.

(mode 10)

The yarn according to any one of aspects 1 to 9, wherein a dielectric is provided around at least a part of the potential generating filament.

(mode 11)

The yarn according to claim 10, wherein the dielectric substance contains an oil agent.

(mode 12)

The yarn according to claim 10 or 11, wherein the dielectric has conductivity.

(mode 13)

The yarn according to any one of aspects 10 to 12, wherein the dielectric includes an antistatic agent.

(mode 14)

The yarn according to claim 10, wherein the dielectric material contains air.

(mode 15)

The yarn according to claim 10, wherein the dielectric material comprises a polymer.

(mode 16)

The yarn according to claim 15, wherein the polymer comprises at least one selected from the group consisting of an ester polymer and a polyurethane polymer.

(mode 17)

The yarn according to claim 10, wherein the dielectric comprises a metal oxide.

(mode 18)

The yarn according to claim 17, wherein the metal oxide is titanium oxide.

(mode 19)

The yarn according to any one of aspects 1 to 9, wherein the yarn does not contain a surface treatment agent.

(mode 20)

The yarn according to any one of aspects 1 to 19, wherein the yarn is an antibacterial yarn.

(mode 21)

A fabric comprising the yarn according to any one of 1 to 20.

Industrial applicability

The invention can be used for a wide variety of products. For example, the yarn can be preferably used as a yarn or a cloth in all kinds of daily products, industrial products, and particularly clothing products using the yarn.

Description of the symbols

1,2: yarn

10: potential generating filaments (or electric field forming filaments)

100: dielectric medium

900: direction of stretching

910A: diagonal line 1

910B: 2 nd diagonal line

Claims

1. A yarn comprising a potential generating filament, characterized in that the yarn has a relative dielectric constant of 4.5 or less.

2. The yarn of claim 1, wherein the relative dielectric constant is 1.0 or more.

3. A yarn as claimed in claim 1 or 2, wherein the yarn has an impedance of 4.0 x 10 ⁶ Omega m or more.

4. A yarn as claimed in claim 3 wherein said impedance is 1.8 x 10 ⁷ Omega m or less.

5. A yarn as in any one of claims 1 to 4, wherein the yarn has an electrical resistivity of 1.4 x 10 ⁴ Omega m or more.

6. The yarn of claim 5, wherein the electrical resistivity is 2.3 x 10 ¹⁵ Omega m or less.

7. A yarn according to any one of claims 1 to 6 wherein the potential generating filaments comprise a piezoelectric material.

8. The yarn of claim 7, wherein the piezoelectric material comprises poly-L-lactic acid (PLLA).

9. The yarn of claim 8, wherein the poly-L-lactic acid (PLLA) has a crystallinity of 35% or more.

10. A yarn according to any one of claims 1 to 9, wherein a dielectric is provided around at least a portion of the potential generating filaments.

11. The yarn of claim 10, wherein the dielectric comprises an oil.

12. A yarn according to claim 10 or 11, wherein the dielectric is electrically conductive.

13. The yarn of any one of claims 10 to 12, wherein the dielectric comprises an antistatic agent.

14. The yarn of claim 10, wherein the dielectric comprises air.

15. The yarn of claim 10, wherein the dielectric comprises a polymer.

16. The yarn of claim 15, wherein the polymer comprises at least one selected from the group consisting of ester polymers and polyurethane polymers.

17. The yarn of claim 10, wherein the dielectric comprises a metal oxide.

18. The yarn of claim 17, wherein the metal oxide is titanium oxide.

19. The yarn of any one of claims 1 to 9, wherein the yarn is free of a surface treatment.

20. The yarn of any one of claims 1 to 19, wherein the yarn is an antimicrobial yarn.

21. A fabric comprising the yarn according to any one of claim 1 to claim 20.