Classifications

• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05F—STATIC ELECTRICITY; NATURALLY-OCCURRING ELECTRICITY
  • H05F1/00—Preventing the formation of electrostatic charges
  • H05F1/02—Preventing the formation of electrostatic charges by surface treatment
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M15/00—Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
  • D06M15/693—Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment with natural or synthetic rubber, or derivatives thereof
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06Q—DECORATING TEXTILES
  • D06Q1/00—Decorating textiles
  • D06Q1/04—Decorating textiles by metallising
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
  • H01B1/20—Conductive material dispersed in non-conductive organic material
  • H01B1/22—Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
  • H01B1/20—Conductive material dispersed in non-conductive organic material
  • H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/922—Static electricity metal bleed-off metallic stock
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2904—Staple length fiber
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2918—Rod, strand, filament or fiber including free carbon or carbide or therewith [not as steel]
  • Y10T428/292—In coating or impregnation
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2927—Rod, strand, filament or fiber including structurally defined particulate matter
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/2964—Artificial fiber or filament
  • Y10T428/2967—Synthetic resin or polymer
  • Y10T428/2969—Polyamide, polyimide or polyester

Definitions

• Electrically conductive fibers composed of (1) a substrate which is a fiber of synthetic organic polymer and (2) a coating adhered to said substrate, said coating being of average thickness of 0.5 to 15 microns and comprising a matrix of a hardened resin mixture of an acrylonitrile-butadiene copolymer and a phenolic resin compatible with the copolymer, and finely divided silver and/or carbon dispersed in said matrix.
• the electrically conductive fibers have a very durable electric conductivity as well as excellent functional properties of normal textile fibers.
• This invention relates to electrically conductive fibers having durable antistatic properties, to a process for making them and to textiles containing them.
• Natural and man-made organic textile fibers generally have the drawback of becoming charged with static electricity when subjected to friction, especially at low humidity. This tendency is especially marked in the case of the hydrophobic fibres, for example of fully synthetic polymers such as polyamides, polyesters, polyacrylates, polyacrylonitrile and polyolefins and fibres of modified natural polymers such as cellulose acetate and triacetate fibres. This phenomenon causes problems not only in the use of textile materials containing these fibres but also in the production of such materials.
• various electrically conductive paints or adhesives are also known; those comprising a conductive 5 Claims "ice material and, for example, an epoxy resin or acrylic resin, are commercially available, and are principally used in the manufacture of materials intended for electrical use, such as electrical terminals, printed circuits, resistors, heating elements and shielding materials.
• these latter paints are of no practical use in preparing textiles having a durably antistatic effect, because when they are applied to organic synthetic fibres having a denier (about 5 to 5 0) in the range used in textiles, the fibres so obtained, although initially of improved conductivity, do not retain this conductivity when subjected to the various conditions (for example friction, repeated flexing, repeated elongation and relaxation, scouring, dyeing and washing) to which textile fibres are subjected during their processing and use.
• the invention provides an electrically conductive fibre composed of (1) a substrate which is a fibre of a synthetic organic polymer and (2) a coating adherent to the substrate, which coating is of average thickness 0.5 to 15 microns and comprises a matrix of a hardened mixture of an acrylonitrile-butadiene copolymer and a phenolic resin compatible with the copolymer, the weight ratio of the copolymer to the resin being 0.4:1 to 4:1, which matrix has dispersed therein finely divided electrically conducting material which comprises one or both of silver and carbon in an amount suflicient to lower the resistivity of the fibre to less than 10 ohm/cm.
• the invention also provides textile materials having durable antistatic properties, which comprise organic textile fibres and a small quantity of electrically conductive fibres as defined above.
• fibre refers, unless otherwise specified, to both staple and continuous fibres.
• the organic synthetic fibres to be used as said substrate are made from linear synthetic polyamides, especialy polycaproamide and polyhexamethylene adipamide, because of the mechanical strength of the fibres made therefrom and the adhesivenes's between these fibres and the conductive coating.
• linear synthetic polyamides especialy polycaproamide and polyhexamethylene adipamide
• other synthetic polymers for example polyesters, polyolefins, acrylic polymers, polyvinyl acetals, polyureas and polyimide and the blends thereof can be used.
• the fibres mentioned above are of about 5 to 50, preferably about 10 to 30, denier.
• the fibre used as starting material is preferably a monofilament, it may also be a multifilament if desired.
• Silver and conductive carbon are selected as the conductive material in view of their weathering resistance, resistance to attack by chemicals, and conductivity. However, a small quantity of finely divided particles of other metals such as aluminium and copper can be added, if desired.
• the finely divided silver can be of any form provided that its average particle size does not exceed 10, preferably 5, microns, but a flat flaky finely divided silver is suitable.
• the fiat flaky silver having an average particle size not exceeding 5 microns is particularly suitable and results in a product having excellent and lasting conductivity, even when the thickness of the conductive coating is extremely thin.
• the carbon can be finely divided graphite and electrically conductive carbon blacks such as acetylene carbon black, conductive furnace black and conductive channel black.
• Acetylene black is preferred because its graphite structure is relatively well developed and its conductivity is superior.
• the particle sizes of carbon blacks are normally determined depending upon the process for their production, and almost all carbon blacks have an average particle diameter of approximately 0.1 In the present invention, all of electrically conductive carbon blacks having such a normal average particle diameter are usable.
• the finely divided graphite that can be employed has an average particle diameter of 0.5/L or below, preferably 0.1 or below. In general, silver gives a product of greater'durability and better appearance than carbon, but the latter is economically more attractive.
• the upper-limit of the amount of the conductive material that can be present in the coating is restricted by the practical requirements of the strength of the coating and the adhesiveness between the coating and the substrate. In general, the presence of silver in the coating in an amount exceeding 90% by weight or carbon in an amount exceeding 60% by weight is not desirable.
• the optimum proportion by weight of the conductive material in the coating will depend upon the kind of the conductive material, its size and shape, and the thickness of the coating. However, from the practical standpoint, an amount ranging from about 70% to 90%, particularly about 75% to 85%, by weight, is preferred when silver alone is used..
• the acrylonitrile-butadiene copolymer contains about 28% to 42% by weight of units derived from acrylonitrile. If the content of acrylonitrile is too small, it frequently happens that the product obtained does not have satisfactory durability to scouring, dyeing and washing. On the other hand the copolymers in which the acrylonitrile content is too great are not desirable since they are not easily managed (specifically, because of their poor solubility since, as hereinafter described, they are dissolved in a solvent and then applied to the fibre). These copolymers may also contain a small amount, such as less than by weight, of units derived from other comonomers having carboxyl groups in its molecule such as acrylic acid and methacrylic acid.
• any phenolic resin which is compatible with said copolymer can be used in this invention.
• the phenolic resin is usually derived from a phenol and an aldehyde.
• a copolymer of relatively high acrylonitrile content is used, a normal phenol-formaldehyde condensation product can be employed, but generally the oilsoluble phenolic resins are preferred.
• examples are phenolic resins modified with natural resins such as rosin or withnatural oils such as cashew nut shell oil, and the condensation products of formaldehyde and a phenol substituted with, for example, a tertiary butyl, tertiary amyl, phenyl or cyclohexyl group.
• Durez 12687 and Durez 11098 are suitable oil-soluble phenolic resins.
• the weight ratio of the acrylonitrile-butadiene copolymer to the phenolic resin is critical for satisfactory strength, softness and flexibility in the coating, adhesiveness to the substrate, resistance to attack by chemicals and resistance to weathering, and hence the durability of the product, and must be 0.4:1 to 4:1, preferably 0.6 :1 to 3: 1.
• the amount of the phenolic resin component in the coating is too small, the strength of the coating, its resistance to chemicals and adhesiveness to the substrate is inadequate, whereas when it is too great, the weight ratio of the acrylonitrile-butadiene copolymer to the phenolic resin is critical for satisfactory strength, softness and flexibility in the coating, adhesiveness to the substrate, resistance to attack by chemicals and resistance to weathering, and hence the durability of the product, and must be 0.4:1 to 4:1, preferably 0.6 :1 to 3: 1.
• the acryonitrile-butadene copolymer and phenolic resin mixture can also contain a phenolic resin hardener, such as hexamethylene-tetramine, thickening agent, antiaging agent or other additives.
• a phenolic resin hardener such as hexamethylene-tetramine, thickening agent, antiaging agent or other additives.
• the thickness of the electrically conductive coating is governed by requirements related to its conductivity as a conductive fibre and to the functional properties (as a textile) of the fibre. While this thickness will be influenced by the particular conductive material present in the coating and its size, shape and quantity, it has been found that the desired conductivity could not be achieved when the average thickness was less than 0.5 micron. On the other hand, the upper average thickness, though influenced by the denier of the substrate fibre, must not exceed 15 microns, but is preferably 1 to 12 microns. An excessively thick coating impairs the functional properties of the product as a textile fibre. When silver alone is used as the conductive material, the average thickness is preferably not. more than 10 microns, and is particularly about 0.7 to 5 microns, whereas in the case of carbon alone, the thickness is suitably at least one micron, particularly about 2 to 12 microns.
• the electrically conductive fibres can be made from the substrate fiber and a paste of the acrylonitrile-butadiene copolymer, the phenolic resin, the finely divided conductive material and a volatile solvent, which is preferably a ketone, such as methyl ethyl ketone or methyl isobutyl ketone, chlorinated hydrocarbon such as dichloroethane, ester such asethyl acetate, nitrated hydrocarbon such as nitromethane, or a mixture thereof or a mixture thereof with a diluent, such as toluene. Thickening agents, antioxidants and other additives as well as curing agents for the phenolic resins can be suitably added to this paste.
• a ketone such as methyl ethyl ketone or methyl isobutyl ketone
• chlorinated hydrocarbon such as dichloroethane
• ester such asethyl acetate
• nitrated hydrocarbon
• the paste is applied to the substrate fibre by dipping, coating, spraying or any other suitable means. If necessary, the amount of paste on the substrate is controlled, for example by passing the fibre through a slit.
• the fibre is dried at, say, about to C., and then heated at, say, about 130 to 210 C., to harden the resin composition.
• the electrically conductive fibres so produced usually have resistivity of about 10 to 10 ohm/cm. when silver alone is present and about 10 to 10 ohm/m. when silver alone is present and about 10 to 10 ohm/cm. in the case of carbon alone.
• resistivity of the fibre can approach that of the case where silver alone has been used.
• This fibre retains its functional properties as a textile fibre and is able to stand up against the usual processing conditions that textile fibres undergo. Hence, its incorporation in the usual organic textile materials is simplified.
• the textile materials having a durable antistaticity are composed of normal organic textile fibres and a small quantity of the aforesaid electrically conductive fibres, and they can have the desired antistaticity and the mechanical properties and appearance that are satisfactory for practical purposes even if only a small quantity, say less than 2%, preferably 0.001 to 1.5%, by weight, of the conductive fibre is present.
• the mixing of the conductive fibre and the organic textile fibres can be carried out by mixed spinning, mixed twisting, mixed weaving, mixed knitting or any other optional technique. Further, the former need not necessarily be distributed evenly in the latter. Carpet yarns, weaving or knitting yarns, or sewing threads can be first mixed with the conductive fibre and then the tufting, weaving, knitting or sewing may be carried out with the mixture, ensuring that the conductive fibre is present at suitable intervals in the end product.
• a shirt may be sewn with a polyester cloth using a sewing thread containing about 8% by weight of the conductive fibre. In this case, the end product shirt contains only a mere 0.02% by weight of the conductive fibre, but it still demonstrates very satisfactory antistaticity.
• the undesirable phenomenon of the skirt and underwear acting together and clinging to the human body is controlled to a marked degree by merely sewing a single line of a conductive fibre in the hemmed portion of the skirt.
• the content of the conductive fibre based on the total skirt can be as little as 0.005% by weight.
• the electrostatic induction may either facilitate the accumulated static charges to dissipate by discharge or cause apparent neutralization of the charges. Further, it is also expected that the charges on the human body may leak to the ground through the conductive fibre, thus preventing the human body from being electrified.
• the textile materials can be for example a staple blend, spun yarn, twisted yarn, tape woven fabric, knit fabric, non-woven fabric, sewed articles or carpet.
• Examples 3A l-7 and 33 1-7 A denier polycaprolactam crimped monofilament.
• Examples 5A and B A 20 denier polyester monofilament.
• Example 6 A 10 denier polyhexamethylene adipamide monofilament.
• Example 7 A 30-denier, S-filament polycaprolactam multifilament.
• the silver used was finely-divided flaky silver of average particle size 1.5 microns.
• the carbon used was acetylene black.
• MATRIX (a) Hardened mixture of acrylonitrile-butadiene copolymer and a phenolic resin
• the acrylonitrile-butadiene copolymer contained 32% acrylonitrile.
• the copolymer contained 37% acrylonitrile.
• the copolymer was a carboxylic acrylonitrile-butadieneggpp mer containing 32% acrylonitrile and about 1 mol p cent carboxyl group.
• the phenolic resin used in Examples 1, 2, 3, 4 and 7 was a mixture of a phenol-formaldehyde resin of the novolac type modified with cashew nut shell oil and a small quantity of hexamethylene tetramine.
• the phenolic resin used in Example 5 was a mixture of a p-tert.butyl phenol-formaldehyde resin of the novolac type and a small amount of hexamethylene tetramine.
• the phenolic resin used in Example 6 was a mixture of a resorcinol-formaldehyde resin and a small amount of hexamethylene tetramine.
• the column headed percent NBR in Table I shows the percentage by weight of copolymer, based on the total of copolymer and phenolic resin, for those examples in which such a mixture provided the matrix.
• Epan epoxy resin type adhesive (P 107-EC produced by Tokuriki Kagaku Kenkyujo, Japan); this suffered from the particular disadvantage that the pot life of the paste containing it was extremely short, thus making it difiicult to obtain a uniform coating, while the cure time required was long.
• Example 1 (4) PRODUCTION OF COATED FIBRE A paste was prepared of the conducting material, the polymeric component(s) which, when hardened, forms the matrix, and a suitable volatile organic solvent.
• Example 2 parts silver, 12 parts acrylonitrile-butadiene copolymer, 8 parts phenolic resin and 80 parts methyl ethyl ketone were mixed; and in Example 2, 25 parts carbon, 45 parts acrylonitrile-butadiene copolymer, 30 parts phenolic resin and 350 parts methyl ethyl ketone were mixed.
• the substrate filament (monofilament in Examples 1, 3, 4 and 6; a plurality of monofilaments separated from each other by a small distance, so that filaments do not stick to each other, in Examples 2 and 5, 30 filaments being processed together in Example 5; a multifilament in Example 7) was passed through the paste at a suitable speed (e.g. 25 metres/minute in Example 1) and then through a slit to adjust the thickness of the coating, and then subjected to a treatment to dry and harden the coating.
• a suitable speed e.g. 25 metres/minute in Example 1
• the drying and hardening treatment used was as follows:
• Fibres with another matrix heat at 190 C.
• Example 3 As for fibres with acrylonitrile-butadiene copolymer/ phenolic resin matrix in Examples 1 and 2, followed by heating of the filament wound up on a bobbin for 30 minutes in a hot air C.) air dryer.
• Abrasion test The filament was rubbed for 15 minutes with a nylon gear (120 r.p.m., diameter 5 cm., number of teeth 20) under a load of 0.36 g./den., calculated on the basis of the substrate fibre.
• the filament was subjected to several scouring treatments, each for 60 minutes at 95 C. in a scouring bath containing 1 g./litre of a non-ionic detergent and 0.3 g./litre of sodium carbonate.
• the filament was dyed with an acid dye by a 60 minute treatment at 95 C. in a dye bath containing the dye and 0.15 g./litre of a surfactant and 0.16 g./litre of ammonium sulphate and adjusted to a pH of 4.6-4.8 with acetic acid.
• Washing test The filament was subjected to washing treatments, each for 30 minutes at 60 C. in a wash liquid containing 1 g./litre of a detergent and 2 g./litre of sodium carbonate.
• the filament was (a) immersed for 20 hours at room temperature in trichloroethylene, tetrachloroethylene, toluene, 10% sulphuric acid, 20% sodium hydroxide and 20% acetic acid; and (b) allowed to stand for 20 hours at room temperature in nitrogen oxide gas, hydrogen sul phide and sulphur dioxide.
• the fibre of Example 1 had a tenacity at break of 5.6 g./den., an elongation at break of 43% and an initial Youngs modulus of 30 g./den. (based on the denier of the substrate). Thus the fibre had a tenacity, softness and flexibility substantially the same as substrate.
• Electrically conductive filaments in Examples 2, 3, 4, 5, and 6 where the substrate fibre is a monofilament and that in Example 7 which has been derived from the multifilament substrate are alike in their tenacity, softness, and flexibility.
• the thickness of an electrically conductive coating of the conductive filament in Example 7 is expressed in an average thickness of a conductive resin adhering to the surface of each component filament in the substrate multifilament.
• Example 8 The monofilament prepared in Example 1 was twisted together with a crimped non-conductive nylon yarn (2600 total denier/ 136 filaments) and to give a conductive nylon yarn which was incorporated into four tufted carpets by disposing a line of the conductive yarns among the nonconductive yarns at every third, sixth, ninth and. twelfth interval respectively.
• a tufted carpet employing only the nonconductive nylon yarn was made as a control.
• the carpets were then scoured, dyed and supplied with backings.
• a person wearing leather-soled shoes then walked over them at 25 C. and 16% relative humidity; the saturated electrification voltage of the persons body and the carpets are shown in Table II.
• the high electrification voltage of the persons body after walking on the control carpet is to be noted; a severe electric shock was received when a grounded conductor such as metal was contacted with the carpet. However, in all other cases the electrification voltage of the body was very low, and no electric shock was felt.
• Example 9 The multifilament yarn prepared in Example 2 was incorporated in a tow with polyvinyl chloride filaments, which tow was crimped and cut to 76 mm. length staple fibre. The crimped conductive fibre retained its conductivity to an adequate degree.
• This staple fibre (70 parts) was blended with polypropylene staple fibre (30 parts), made into a web and then into several nonwoven carpets by the needle punch method.
• the content of the conductive fibre in the carpets was varied by adjusting the number of filaments in the conductive multifilament yarn incorporated into the tow.
• a person wearing leather-soled shoes walked over these carpets and a control carpet at 25 C. and 27% relative humidity; the voltages of the persons body in each case are shown in Table III.
• a very high electrification voltage was built up in the body with the control carpet and a severe shock was received when a grounded conductor such as metal touched the latter. In all the other cases, however, the voltage built up in the body was extremely low and no such shock was felt.
• Example Nylon tufted carpets were made as in Example 1 from the filaments prepared in Examples 3 A4 and 3 B-4, incorporating the filaments at every third interval. The carpets were abraded with a reciprocating rotary polyvinyl chloride friction element (1 cm. wide; r.p.m.;
• a fabric having a very excellent antistatic elfect could be obtained by incorporating there n a small amount of the conductive filament having a resistivity falling within the range normally possessed by a high electric resistance [5x10 ohm/cm. (Example 4 A4)].
• Example 12 A 60 count sewing thread was made by twisting in a single line of the conductive monofilament prepared in Example I with a polyester multifilament, and was used to sew a shirt of tricot composed of polyester fibre (conductive monofilament content about 0.04%).
• This shirt and a control shirt sewn with conventional sewing thread were washed for 5 minutes with a nonionic detergent in a home electric washer.
• a dressing-undressing electrification test was carried out at 25 C. and 25% relative humidity on these shirts by a person wearing a polyvinyl chloride fibre undershirt.
• the control shirt produced a harsh discharge noise when the shirt was removed; the shirt also clung to the persons body.
• the control shirt produced high electrification voltages on both the body and the shirt after the latters removal, the measurement being made on the back portion of the shirt. With the shirt containing the conductive filament, the electrification voltages of the persons body and the shirt were very low even though the amount incorporated was extremely small.
• the test was repeated after the shirts had been washed a number of times, as shown in Table V, which shows that the improved effect was not lost, thus demonstrating its excellent durablity.
• the multifilament yarn prepared in Example 5 was cut into staple fibres, which were mixed in various proportions with polyacrylonitrile staple fibres (3 denier; 76 mm.) and the staple fibre masses were rubbed with an acrylic resin plate at 25 C. and 40% relative humidity until the electrification voltage was constant.
• the electrification voltages (measured 30 see. after rubbing) of the samples are shown in Table VI.
• Example 15 Twill fabric of polyethylene terephthalate/ cotton blend was prepared, incorporating the electrically conductive filaments obtained in Example 7 in the warp direction at intervals of 5 cm. Wor-k wears were sewn from the twill fabric and scoured.
• An electrically conductive fiber for imparting durable antistatic properties to an electrically non-conductive textile material comprising (1) a substrate of an organic synthetic fiber of 550 denier, and
• said coating comprising a hardened polymer matrix of an acrylonitrile-butadiene copolymer and a phenolic resin compatible with said copolymer in the weight ratio of from 0.421 to 4:1, said matrix having dispersed therein finely divided particles of one or both of silver and carbon, the average thickness of said coating being 0.5 to 15 microns, and the amount of said particles being suflicient to reduce the resistivity of said electrically conductive fiber to less than 10 ohms per centimeter.

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• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Dispersion Chemistry (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Woven Fabrics (AREA)
• Multicomponent Fibers (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=12505727

Family Applications (1)

Country Status (5)

Cited By (7)

Families Citing this family (1)

• 1969
  • 1969-05-26 US US827931A patent/US3669736A/en not_active Expired - Lifetime
  • 1969-05-29 GB GB1259315D patent/GB1259315A/en not_active Expired
  • 1969-06-02 BE BE733953D patent/BE733953A/xx unknown
  • 1969-06-04 FR FR6918358A patent/FR2010124A1/fr active Pending
  • 1969-06-04 NL NL6908473A patent/NL6908473A/xx unknown

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