US3666550A - Textile materials having durable antistatic properties - Google Patents

Abstract

A TEXTILE MATERIAL HAVING DURABLE ANTISTATIC PROPERTIES, SAID MATERIAL COMPRISING ORGANIC TEXTILE FIBERS AND A MINOR AMOUNT OF ELECTRICALLY CONDUCTIVE FIBERS, EACH OF SAID ELECTRICALLY CONDUCTIVE FIBERS COMPROSING A SUBSTRATE OF ORGANIC SYNTHETIC FIBER AND A METALLIC COATING CHEMICALLY DEPOSITED THEREON, SAID ELECTRICALLY CONDUCTIVE FIBER POSSESSING THE FUNCTIONAL PROPERTIES OF TEXTILE FIBERS.

Description

United States Patent US. Cl. 117-217 6 Claims ABSTRACT OF THE DISCLOSURE A textile material having durable antistatic properties, said material comprising organic textile fibers and a minor amount of electrically conductive fibers, each of said electrically conductive fibers comprising a substrate of organic synthetic fiber and a metallic coating chemically deposited thereon, said electrically conductive fiber possessing the functional properties of textile fibers.

This invention relates to textile materials having durable antistatic properties.

Organic textile fibers have, in general, the shortcoming that they become charged with static electricity upon being rubbed especially at low humidity. This tendency is particularly great in the case, for example, of the synthetic fibers such as polyamide, polyester, acrylic and polyolefin fibers, as well as semi-synthetic fibers such as acetate and triacetate fibers. This electrification phenomenon becomes also a problem during the manufacture of textile products.

As one means of solving this problem, it has been suggested to incorporate a small amount of metallic fibers in the textile material (US. Pat. 3,288,175). However, since the usual textile fibers differ essentially in nature from the metallic fibers, there were problems in the mixing and processing steps as well as the hand of the resulting product. Furthermore, the manufacture of metallic fibers in fine denier is not simple, and this process frequently results in the cost of the fiber becoming high.

It was found that if the thickness of the metallic coating is adjusted to 0.01-1.5 microns in chemically plating a metallic coating on an organic synthetic fiber made of an acrylic polymer consisting essentially of at least 80 mol percent acrylonitrile to render it electrically conductive, the resulting product retains its functional properties as a textile fibers; and that the incorporation of about 0.01-2%, based on the weight of said organic textile fibers, of such electrically conductive fibers in the usual organic textile fibers made it possible to control the undesirable electrifying tendency of the latter very readily and lastingly.

The term fiber, as used herein and the appended claims, unless otherwise noted, comprehends those of staple fiber form as well as those of continuous filament form.

As the organic synthetic fibers to be used as the substrate of the electrically conductive fibers, particularly to be preferred from the standpoint of the ease of application of the metallic coating and their ability to adhere metals are those of acrylic polymer in which the content of acrylonitrile is at least 80 mol percent and those of polyester whose content of ethylene terephthalate is at least 80 mol percent, but the fibers of the other synthetic polymers such, for example, as polyamide, polyvinyl acetal, polyolefin, polyurea and polyimide can also be used. It is also possible to use a fiber in which an undercoat layer comprising an organic polymeric material is formed on the substrate fiber in order to enhance its adhesion to a metal coating. The substrate fiber can have a textile denier of about 1-50 deniers.

3,666,550 Patented May 30, 1972 The metallic coating can be applied to the substrate by the method which per se is known for chemical plating of organic polymeric materials, optionally followed by electroplating. Chemical plating can be carried out on substrate fibers of multifilament, monofilament or staple form.

As examples of metals suitable for chemical plating on the substrate, there are nickel, copper, cobalt, chromium, zinc and tin, but from the standpoint of ease of plating and economy nickel and copper are of advantage.

In carrying out the chemical plating of shaped articles such as cast articles of organic polymeric materials, the general practice is to perform such pretreatments as mechanical roughening, degreasing, etching, sensitizing and activation of the surface. The step of mechanically roughening the surface is performed with a view of forming a rough surface suitable for performing the metallic plating, but in the case of a substrate of fiber form, it was found that this step was not particularly necessary, since the surface of the fiber is roughened to a suitable extent to be already convenient for carrying out the metallic plating operation.

The degreasing step whose purpose is to clean the surface of the substrate fiber and remove such soiling as oils and fats, can be readily carried out by means of the usual neutral or weakly alkaline detergents. The oiling agents which have been adhered to the fiber during its manufacture can usually be removed fully by a simple degreasing treatment, and it is also possible, depending upon the substrate, to proceed to the next step Without performing the water-washing and degreasing treatment.

The etching step is for exposing a hydrophilic surface by swelling the surface of the substrate and chemically corroding it, which is an especially important step in ensuring the adhesion of the metal to the substrate.

As the etchant that is especially effective with the acrylic fibers, included are the acid etchants such as chromic acidsulfuric acid, potassium bicromate-sulfuric acid, potassium bichromate-phosphoric acid, nitric acid, and chromic acidnitric acid, and the alkaline etchants such as caustic soda. and caustic potash. While the acrylic fibers are essentially superior in their resistance to chemical attack and resistance to heat, it is still necessary to exercise care to ensure against their degradation since a fine fiber is to be used as the substrate. Hence, it is important to choose conditions which are optimum for obtaining satisfactory adhesiveness between the substrate and the coating. Generally speaking, the fiber need not be subjected to a harsh etching; an etching treatment for a short period of time under mild conditions should be sufficient. For example, when the chromic acid-sulfuric acid type of etchant [50-l00 g./l. of chromic anhydride plus 100-300 g./l. of concentrated sulfuric acid is used, the end can be fully achieved by a treatment for 5 seconds to 5 minutes at room temperature.

The substrate fiber which has received the etching treatment is usually submitted to a sensitizing and activation pretreatment before being chemically plated.

The sensitizing step consists in causing the adsorption and orientation of a reducing agent on the surface of the substrate which has been rendered hydrophilic in the etching step, and as the sensitizing bath, an acid or alkaline bath of a stannous compound, such as stannous chloride, titanium trichloride or aluminum chloride can be used, but from the standpoint of sensitizing effect and economy, a stannous chloride-hydrochloric acid type sensitizer, e.g. a bath consisting of 5180 g./l. of stannous chloride and 1-180 cc./l. of concentrated hydrochloric acid (35%), is particularly convenient, the end being fully achieved by a treatment of 3 seconds to 3 minutes at room temperature to 50 C.

The activation step consists in depositing on the surface of the substrate a noble metal such as palladium, platinum, gold and rhodium, which is active as catalysts in carrying out the chemical metal plating. While any of the known activators is effective, especially convenient is the palladium chloride-hydrochloric acid type activator (e.g. a bath consisting of 0.025-5 g./ l. of palladium chloride and 0.25- 25 g./l. of concentrated hydrochloric acid (35%)), the end being fully achieved by a treatment of 3 seconds-6 minutes at room temperature to 60 C.

Next, the chemical metal plating is carried out on the surface of the fiber. As previously stated, particularly preferred is either a chemical nickel plating or chemical copper plating. As the composition of the chemical nickel plating bath, several types can be mentioned, such as soluble nickel salt-hypophosphite, soluble nickel salt-boron nitrogen compound, and soluble nickel salt-urea. While basically any of these compositions can be used with full satisfaction, convenient is the bath whose composition is of the soluble nickel salt-phosphite type, and particularly preferred is that of this type which is acidic. An excellent electrically conductive fiber can be obtained With a very short period of treatment by the use a relatively high plating bath temperature. For example, when an acidic plating bath consisting predominantly of 20 g./l. of nickel sulfate, 24 g./l. of sodium hypophosphite and 27 g./l. of lactic acid and whose pH has been adjusted to 5.6 is used, satisfactory treatment is obtained with a plating bath temperature of 60-98 C. and a treatment time of 10 seconds-9 minutes. Particularly, if the treatment is carried out at a plating bath temperature of 80-90 C., a fiber excelling in electric conductivity can be obtained satisfactorily even with a treatment time of less than one minute. Since, as hereinbefore described, the chemical nickel plating can be carried out under treatment conditions requiring a very short period of time, it is especial: ly convenient to use it in the continuous chemical plating of filaments.

As the bath composition for chemical copper plating, combinations consisting of soluble copper salts and the various reducing agents can be mentioned, but especially suitable is that of the soluble copper salt-formalin type. Chemical copper plating generally has the shortcomings that its bath life is short and the deposition speed is slow, but it is featured in that even though the plate thickness is quite thin a very uniform durable electrically conductive fiber can be obtained whose conductivity is superior, adhesion is good and, in addition, pliability and flexibility are also excellent. When, as the soluble copper salt-formalin type chemical plating bath, for example, one consisting of 30 g./l. of copper sulfate, 100 g./l. of Rochelle salt and 50 ml./l. of formaline (37%) as principal components and adjusted to pH 11-12 with sodium hydroxide is used, a treatment for 3-10 minutes at room temperature is sufiicient to yield an excellent electrically conductive fiber.

It was found surprisingly that a good metallic coating could be formed on the substrate even when the hereinbefore described etching step was omitted when an acrylic fiber was used as the substrate. It was found moreover that the adhesiveness of the metallic coating to the substrate was far superior to that in the case where the other fibers were used. While this has not been fully clarified as yet, it is believed that it is ascribable to the inherent surface configuration of the acrylic fiber (the acrylic fiber has chiefly a dog-bonelike cross-section and the sectional configuration in the axial direction of the fiber varies greatly in an irregular manner) and the affinity between the nitrile group in the substrate and the metal (chelating effect). 1

. The metallic coating which has been chemically plated on the substrate fiber can, if desired, be increased in its thickness by further deposition of metal thereon by electroplating. The metal to be electroplated may be one which is the same as that which was chemical plated or one dilfering therefrom.

The thickness of the metallic coating formed on the substrate fiber must be controlled so as to ensure that the product retains the functional properties of textile fibers. A metallic coating of excessive thickness results in a prodnot having poor pliability and flexibility and is also unnecessary from the standpoint of conductivity. The upper limit of the average thickness of the metallic coating will depend upon the class and denier of the substrate fiber, the class of metal, and the use to which the final product is to be put, but in most cases it should not exceed 1.5 microns. On the other hand, the lower limit of the average thickness of the metallic coating will suflice with one which will render the fiber conductive, i.e. the thickness which will ensure a volume inherent resistivity of l0- l0. fl-cm. It was found that there were frequently discontinuities in the metallic coating whose average thickness was less than 0.01 micron and, as a result, that the coated product frequently did not have a satisfactory conductivity. Hence, it is preferable to control the average thickness of the metallic coating to within the range of 0.01 to 1.5 microns, and particularly 0.1 to 0.5 micron.

A top coating of an organic polymeric material can be applied to the electrically conductive fiber to protect the metallic coating from being oxidized and corroded and peeling off from the substrate. However, this top coating must be one that does not make the electric resistance of the fiber greater than about 2000M0/cm. As the organic polymeric material to be applied, preferred are the synthetic rubber type polymers which excel in their adhesiveness to metal and the water-repellent silicon resin type polymers, but others can also be used.

The textile materials having durable antisatic properties in accordance with this invention comprise the usual organic textile fiber and a minor amount of the hereinbefore described electrically conductive fiber. The aforesaid electrically conductive fiber can be present in the textile material and product according to the invention in a proportion of 0.01% to 10% by weight. Thus, 0.01% to 2% and preferably 0.05% to 2% by weight based on the organic textile fiber may be employed. With a proportion of the electrically conductive fiber of less than 0.01% by weight it frequently happens that a pronounced antistatic effect cannot be achieved, whereas with a proportion of the eelctrically conductive fiber of 2% to 10% by weight, the rate of improvement in the antistatic elfect in proportion to the increase in the electrically conductive fiber hardly increases. The use of the electrically conductive fiber in excess of about 10% by weight is unnecessary. In fact, little is to be gained in employing over 2% conductive fiber.

The electrically conductive fiber can be combined with the ordinary organic textile fibers by an optional means such as mix spinning, mix twisting, mix weaving and mix knitting. And in this case, it is not necessarily required that the former is evenly distributed in the latter. For example, a textile fabric according to this invention can be Woven by distributing one end of woof yarn containing the electrically conductive fiber at an interval of 10 to ends of the woof yarns while using the ordinary warp yarns.

The electrically conductive fibers used in the invention include not only those in which an electric resistance is in the region of an ordinary conductor, but also those in which an electric resistance is very high such as 2,000M0/cm. as in the case of forming a top coat layer comprising an organic polymer. It is surprising that a marked antistatic effect is exhibited even when a small amount of a fiber having such high electric resistance is incorporated. 'It is not easy to explain the mechanism of prevention of electrification with simplicity. Generally, a high voltage above 1000 volts poses a problem in an unfavorable electrification of ordinary organic textile fibers, and a quantity of electrostaticity generated at this time is very small. Hence, it is presumed that even in the case of such high electric resistance, the local intrinsic electric breakdown of the coating occurs under such high voltage, and the electrostatic charge is easily dispersed by such effects as gaseous corona discharge, surface flashover and tracking and leakage, thus preventing the accumulation of electrostatic charge. This seems to contribute greatly to the prevention of electrostatic charge.

The textile materials having durable antistatic properties can be of any form, including staple blend, spun yarn, twisted yarn, string, cord, tape, woven, knitted or non-woven fabrics and carpets.

The following examples are given for further illustratron of this invention. The volume inherent resistivity values of the electrically conductive textile material given in the examples are computed by multiplying resistance values per unit length of the fiber measured with a universal bridge (Model BV-Z-13A) manufactured by Yokogawa Electric Works, Japan by the total cross-sectional area of the electrically conductive fiber (including the substrate and metal coating), while the electrification voltage values were measured by a collecting type potentiometer (Model KS-325) manufactured by Kasuga Electric Company, Japan. The content of the electrically conductive textile material is shown in weight percent of the and its initial Youngs modulus is 100 g./de. (computed in terms of the denier of the substrate filament, the values of the substrate filament were 3.6 g./de., 13% and 90 g./de., respectively), and its retains practically the same pliability and flexibility as that of the substrate itself.

Carpets incorporated with this electrically conductive monofilament were made by first mixing in this filament during the twisting step of Taslon treated nylon yarn (2600 total denier/136 filaments) and by incorporated the electrically conductive monofilament-incorporated nylon yarn at two and five strand intervals (rate of mix 0.17 and 0.08%, respectively) during the tufting operation. The so made carpets were then scoured, dyed and applied a backing. When the so obtained tufted carpets were used and the measurement of the electrification voltages was made by having a person walk thereover wearing leather-soled shoes and under the conditions of C. and 10% RH, the electrification voltages of the human body and carpets were as shown in the following table. It was thus seen that the electrification voltages of the human body and carpet could be decreased greatly by the incorporation of a very small amount of the electrically conductive filament.

Content of Electrification voltage Electrification voltage electrically of human body (volts) of carpet (volts) conductive filament Normal Shufiling N ormal Shufiling Carpet (percent) walk walk walk walk Electrically conductive filament not incorporated 0 -5, 000 -13, 500 +6, 000 +15, 000 Electrically conductive filament incorporated at 2 Strand intervals 0. 17 -l, 000 2, 000 +2, 000 +2, 600 Electrically conductive filament incorporated at 5 strand intervals 0.08 -1, 000 -2, 000 +2, 000 +2, 500

material contained based on the organic textile material, while the composition of the substrate organic synthetic fiber or filament is shown in mol percent.

EXAMPLE 1 A degreased 10 denier acrylic monofilament (a copolymeric fiber containing 94.5% acrylonitrile, 4.5% methyl acrylate and 1% of another third component, wet spun by means of dimethylformamide) was continuously and successively immersed and passed through the following baths to deposit the chemical nickel plating.

(a) sensitizing bath (20 g./l. stannous chloride, 10 g./l. conc. hydrochloric acid) Room temperature 8 seconds. (b) Water-washing 'Room temperature '8 seconds.

(c) Activating bath (0.25 g./l. palladium chloride, 2.5 g./l. conc. hy-

drochloric acid) Room temperature '8 seconds. (d) Chemical nickel plating bath (predominantly 20 g./l. nickel sulfate, 24 g./l. sodium hydrophosphite, 27 g./l. lactic acid; pH adjusted to 5.6) 88C., 80 seconds. (e) Water-Washing Room temperature '8 seconds.

Thus, an electrically conductive filament having a nickel coating of an average thickness of 0.4 micron was obtained continuously. This filament has good conductivity, since its average volume resistivity is -1.0 l0' n-cm. Even after it was submitted to a test of its resistance to friction [the filament is rubbed for 5 minutes under a load of 0.5 -g./de., based on the substrate fiber, against a nylon gear (module 3.61, number or teeth 40) rotating at 120 r.p.m.], there was practically no change in the resistance value, thus demonstrating the excellent adhesiveness of the nickel coating. The breakage strength of this filament is 3.6 g./de., its elongation at break is 14% In the case of a nylon tufted carpet not incorporated with the electrically conductive filament, a high voltage of static charge, as shown in the foregoing table, was accumulated in the human body by walking in normal manner or in a shufliing manner. And in this case, an unpleasant severe shock is received in both cases when a metallic door knob is touched. On the other hand, in the case of the carpets incorporated with a small amount of the electrically conductive filament, in both cases the electrification voltage of the human body is very low and no shock is received.

EXAMPLE 2 A degreased 200 total denier/ filaments acrylic multifilament (a copolymeric fiber containing 94.5% acrylonitrile, 4.5% methyl acrylate and 1% of a third component, wet-spun by means of nitric acid) was used as the substrate, which was applied a chemical copper plating by being treated in sequence by the following baths; (a) an etching bath (75 g./l. chromic anhydride, 250 g./l. concentrated sulfuric acid), treatment for 15 seconds at room temperature; (b) water-washing bath; (c) sensitizing bath (a bath composition identical to that of Example 1), treatment for 15 seconds at room temperature; (cl) waterwashing bath; (e) activation bath (a bath composition identical to that of Example 1), treatment for 15 seconds at 50 C.; (f) water-washing bath; (g) chemical copper plating bath (a copper salt-formalin type chemical plating bath consisting of 30 g./l. of copper sulfate, 100 g./l. of Rochelle salt and 50 ml./l. of formalin as principal components, and adjusted to a pH of 11-12 with sodium hydroxide), treatment for 6 minutes at room temperature; and (h) water-washing bath. Thus was obtained an electrically conductive filament excelling in flexibility and pliability having a copper coating of average thickness of 0.062 micron and an average volume inherent resistivity of. 2.9 10 item. The conductivity of this filament changed hardly at all even when it was submitted to the test of its resistance to friction by means of a nylon gear, as in Example 1. It is to be noted that in the case of a filament applied the chemical copper plating, the conductivity and adhesiveness are excellent even with a very thin plate thickness.

This electrically conductive filament was mixed with a degreased 24,200 total denier/ 8300 filaments nylon'filament, in a prescribed amount, and the filament was then electrified to saturation by rubbing on glass tube under the conditions of 20 C. and 40% RH. The filament was then held above the center of the metallic disk of a foil electroscope at a point 1 cm. thereabove in a straight line and the angle of spread of the leaves was determined, with the results shown in the following table. It is seen that a very excellent antistatic effect is demonstrated by the incorporation of only a small amount of the electrically conductive filament.

. Rate of leaf Content of electrically conductive Leaf spread spread ar gle filament (percent) angle (degree) (percent) EXAMPLE 3 8 EXAMPLE 4 Chemical nickel plating was applied to degreased 3 denier x. 76 mm. acrylic staples by operating as in Example 3, whereby were obtained electrically conductive staples having an average thickness of the nickel coating of 0.27 micron and an average volume inherent resistivity of 7.8x 10- Q-cm. A non-woven carpet was made by binding a web composed of 70% by weight of polyvinyl chloride staples and 30% by weight of polypropylene staples by the needle punch method and further binding the web by spraying a bonding agent against the back. When this carpet was vigorously rubbed by a person Wearing shoes under the conditions of 25 C. and 12% RH, the human body and the carpet showed a charge of +6000 and 8000 volts, respectively, and the severe shocks were felt by the person when he touched a metal. However, in the case of a non-woven carpet in which was dispersingly mixed in the web 0.3% of the electrically conductive staples, obtained as hereinbefore described, the electrification voltages of the human body and carpet were only +2000 and 2000 volts, respectively, and no shock was felt by the human body upon touching a metal as in the foregoing instance. Thus, the antistatic effect demonstrated was pronounced.

EXAMPLE 5 The electrically conductive filament applied with the chemical nickel plating, as obtained in Example 1, was used as the cathode, and an electrolytic copper plating was also applied to the filament in an acid copper sulfate bath with a current density of 0.5 A./dm. Thus, an electrically conductive filament having a further copper coat- Fiber properties (calculated on the basis of the denier of the substrate filament) Average thickness Breakage Initial of nickel Breakage elon- Youngs coatin Average inherent restrenght gation modulus (micron sistivity (S2- cm.) (g./de.) (percent) (g.lde.)

Specimen No.:

1 0. 005 Discontinuity in the 3. 1 19 75 adhesion of metal. No couducitivity 0. 03 5 10- 3. 1 20 77 0. 4 1 1o- 3. 0 18 100 0. 9 4X10. 2. 1 10 115 5 2. 0 2X10. 1. 0 1 210 Substrate filament 3. 1 78 When the fiber properties of the several electrically conductive filaments and the properties of the substrate filament are compared, it is shown that While the electrically conductive filaments of specimen Nos. 2, 3 and 4 still retain their pliability and flexibility as organic textile materials, the electrically conductive filament of specimen No. 5, having already lost its functional properties as an organic textile material, has been converted to one having the properties of a metallic wire.

When an electrification test was conducted as in Example 3, by mixing one strand of each of the electrically conductive multifilaments of specimen Nos. 2, 3 and 4 in a degreased 13,000 total denier/6220 filaments acrylic filament and making the measurements using a, foil electroscope, the results obtained were as follows. In all cases, a pronounced antistatic eifect was demonstrated.

Content of electrically conductive Leaf spread Rate ofleal ing to an average thickness of 0.35 micron and an average volume inherent resistivity of 5.8 10- Sl-cm. was ob tained. A polyester plain fabric was obtained. A polyester plan fabric was woven with this filament incorporated at intervals of 1 cm. in the woof and warp directions (content 0.16% by weight). A 10 cm. x 10 cm. test piece, after scouring was caused to be electrified to saturation by rubbing it with an acrylic fiber cloth at a speed of 6 cm. per second at 20 C. and 40% RH. When its electrification voltage was measured 30 seconds later, it was only 420 volts, as compared with 7300 volts in the case of the cloth not incorporated with the electrically conductive filament. It was thus seen that this electrically conductive filament had a very excellent antistatic effect.

EXAMPLE 6 The filament obtained in Example 1 was dipped in nitrile rubber-phenol type bonding agent, then passed. through a slit to adjust its film thickness, dried and. hardened at C. to obtain a resin-coated electrically conductive filament having an average resin film thickness of 0.3 micron and an average resistance value of ZOOOMQ/cm. [measured by the automatic insulation resistance meter (Model L-68) mfg. by Yokogawa Electric Works, Japan]. A nylon tufted carpet was made as in Example 1 incorporating this filament as every other strand (content 0.26%). When this was then measured Electrifica- Content tion voltage Specimen (percent) (volts) Not incorporated with electrically conductive filament 2, 000 Incorporated with electncaly conductive filament not coated with resin 0.25 800 Incorporated with resin-coated electrically conductive filament 0. 26 750 Further, when the hereinabove described carpet test pieces were measured for their electrification voltages after being rotatingly rubbed by means of a jagged vinyl chloride resin frictional element (load 0.5 kg./cm. 23 rpm), the results were as shown in the following table. The durability and resistance to abrasion were thus shown to be very excellent.

Electrification Friction applied: voltage (volt) Before abrasion 750 After 500 rotations 850 After 1000 rotations 850 We claim:

1. A textile material having durable antistatic properties comprising organic textile fibers and electrically conductive fibers, characterized in that said electrically conductive fibers are incorporated in said organic textile fibers in an amount of about 0.1-2% by weight of said organic textile fibers, and each of said electrically condnctive fibers comprising a substrate of organic synthetic fibers made of an acrylic polymer comprising at least 80 mol percent of acrylonitrile which has been sensitized by adsorption of a reducing agent thereon, and then has been activated by deposition of a noble metal thereon, and an clectrolessly plated metallic coating on said substrate, the average thickness of said metallic coating being about 0.01-1.5 microns.

2. A textile material according to claim 1 wherein said electrically conductive fiber comprises a substrate of organic synthetic fiber, an clectrolessly plated metallic coating thereon, and a top coating layer of organic polymeric material over said metallic coating to protect the metallic coating, said top coating layer being such that it does not cause the electric resistance of said fiber to exceed about 2000MSZ/cm.

3. A textile material according to claim 1 wherein said metallic coating comprises a metal selected from the group consisting of nickel and copper.

4. A textile material according to claim 1 wherein said material is in the form of staple blend, spun yarn, twisted yarn, string, cord, tape, woven fabric, knitted fabric, non-woven fabric or carpet.

5. A textile material according to claim 1 wherein said metallic coating comprises at least one metal selected from the group consisting of nickel, copper, cobalt, chromium, zinc and tin.

6. A textile material according to claim 1 wherein the substrate fiber has a finess of about 1 to denier.

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