Abstract: An insulated conductor having improved arc propagation resistant properties. The insulation consists of a first layer of a composite tape of polyimide between two layers of polytetrafluoroethylene. The second overlaying tape layer is unsintered polytetrafluoroethylene. Further disclosed is a process for manufacturing a sintered wire product having a tin plated electrical conductor.

Abstract: Existing electrical cables (such as low speed data, low or high speed computer or telephone cables) employ connectors having holes or other openings for receiving the insulation or requiring conductors having a precise pitch. For example, a mechanical part of the connector may close over the received cables, piercing the insulation and making an electrical contact with the conductor inside the insulation. Or, the insulation may also be used to provide the spacing required for mass termination of insulation such as connectors which require a specified pitch. This dimension or pitch is supplied by the inner insulation while the outer insulation supplies the dimension required to meet the impedance/capacitance requirements of the electrical circuits involved. The modern high speed data cables must have substantially more insulation so that the capacitive loading or impedance match of the wire is at an acceptable level.

Abstract: An elongate body insulated by means of an insulating covering, said covering being constituted by a tape (2) made of synthetic material taped around said body (1) and covered in a layer of varnish (11) made of synthetic material, the body being characterized in that the taping is such that there exists a groove (4) between the free edge (5) of any portion of a turn (3) that is not covered by the following turns and the uncovered surface (6) of the preceding turn, the width of said groove (4) lying substantially in the range 0% to 5% of the width of said tape (2) and being strictly greater than zero.

Abstract: An electrical cable having a wire bundle core surrounded by a thermal protection sleeve, the thermal protection sleeve consisting of a sandwich structure of a laminate of silicone foam provided on both sides with an acrylic adhered layer of fiber glass, the sandwich structure having an additional outer layer of acrylic adhesive adhered silicone release liner material or fiber glass lacing tape.

Abstract: A process for producing an insulated electric wire, comprising the steps of coating around a conductor an energy radiation curable resin composition having heat expansible microspheres incorporated therein, and curing the energy radiation curable resin composition thus coating on the conductor by exposure to an energy radiation. The process also comprises the step of heating the energy radiation curable resin composition to expand the heat expansible microspheres in the energy radiation curable resin composition, thereby forming a high-porosity insulation layer on the conductor. An insulated electric wire comprises a conductor; an energy radiation curable resin composition layer having microspheres incorporated therein and surrounding the conductor, the outside diameter of the microspheres in the energy radiation curable resin composition layer being maximum in the vicinity of the conductor and decreasing gradually toward the periphery of the energy radiation curable resin composition layer.

Abstract: A composition useful in the manufacture or cable comprising:(i) a copolymer comprising ethylene and one or more alpha-olefins having a density equal to or less than 0.915 gram per cubic centimeter;(ii) a metal hydrate flame retardant compound;(iii) a styrene-ethylene-butylene-styrene triblock copolymer; and(iv) optionally, an impact polypropylene copolymer or polypropylene.

Abstract: A fire-resistant cable (20) which is suitable for the transmission of high frequency signals in a local area network includes a core which comprises a plurality of twisted pairs (22,22) of insulated conductors (24,24) and a jacket (35). Each insulated conductor of each pair includes an elongated metallic member (26) and an insulation system (28). The insulation system which is characterized by a suitable low dissipation factor includes dual layers, an outer one of which includes a flame-retardant plastic material. Also, the insulation system is characterized by a suitably low dielectric constant and by compatibility with a relatively short pair twist scheme. In one embodiment, the insulation system includes an inner layer (30) of a polyolefin plastic material and an outer layer (32) of a flame-retardant polyolefin plastic material.

Abstract: A process for extruding a thermoplastic polymer comprising:(a) introducing into an extruder a copolymer of ethylene wherein one of the copolymerized monomers has the following formula:CH.sub.2 .dbd.C[(CH.sub.2).sub.n --CH.sub.3 ]-Si(OR).sub.3wherein eachR is independently a saturated aliphatic group having 1 to 4 carbon atoms; andn is 0, 1 or 2;(b) extruding the copolymer of step (a); and, thereafter,(c) contacting the extrudate with sufficient moisture to effect crosslinking.

Abstract: A polyol-water mixture is applied over the polymeric insulation of the or each conductor core of an electrical cable prior to extruding the polymeric sheath of the cable thereover such that the polymeric sheath is prevented from adhering to the polymeric insulation.

Abstract: An abrasion- and termite-resistant cable comprises at least one elongate functional element coated with at least two concentric layers of polymeric material, the exterior layer being a polyamide and the layer adjacent thereto being an essentially olefin polymer which comprises from 0.001 to 30% by weight of polar monomer selected from unsaturated acids and acid anhydrides. Other monomers and properly-modifying polymers may also be present in the olefin polymer. These layers are applied in a single operation wherein at least one of the polymeric materials is in a fluid state when the materials are contacted.The invention permits the construction of a cable with an unusally thin polyamide layer. It also permits the extrusion of the layers on an aluminium-sheathed functional element without the need for an adhesion-promoting layer on the aluminium.

Abstract: Magnet wire substrates (1) are described having a layer of polyester tape (2) wrapped thereon, including a layer of spirally wrapped and bonded polyester insulation tape (3) as the outermost layer. The two tape layers are made up of amorphous (4) and crystalline (5) segments unbonded to the wire and bonded to each other to provide the requisite electrical properties and improved physical properties including increased flexibility and ease of strippability. A single multilayer polyester insulation tape can also be used with similar properties and reduced thickness.

Abstract: Magnet wire is insulated with a paper insulation sheet which is longitudinally wrapped onto the wire. The paper sheet is precoated on one side with a layer of resinous adhesive dielectric material such as a thermoplastic polyester. The outside surface of the paper sheet has the resinous coating applied thereto and solidified prior to the time that the paper is wrapped onto the wire. Just prior to applying the paper to the wire, an edge of the resin coating is heated sufficiently to locally remelt the resin. The remelted edge is then overlapped by the opposite edge as the coated paper is wrapped onto the wire, whereby the edges of the insulation sheet are adhered together. The wrapped wire is then passed through one or more heated dies in order to remelt the entire resin coating, which remelted coating is then drawn back over the exterior of the paper layer. The wrapped wire is then passed through a water quench bath.

Abstract: In an insulating system for high-voltage machines, a three-layer insulating tape is proposed as turn-to-turn insulation which comprises a center mica layer (1) which is covered on both sides by plastic foils (2,3) having different thickness. Thermoplastic adhesive layers (4,5) on the outer surfaces of the foils (2,3) produce an intimate bonding of the turn-to-turn insulation to the conductor elements and to the main insulation. An insulation of such construction is distinguished by a high electrical life at increased temperature and a high surge withstand capability.

Abstract: This invention relates to an expandable tape for use in making cables. The expandable tape comprises a carrier material carrying thermally expanding microcapsules therein or thereon. The invention also relates to the use of the tape in the manufacture of cables, and to the cables incorporating such tape.

Abstract: A cable which may be used in buildings in concealed areas such as in plenums or in riser shafts includes a core (22) which includes at least one transmission medium each of which is enclosed with a non-halogenated plastic composition of matter. The core is enclosed with a jacket (28) which also is made of a non-halogenated plastic composition. The non-halogenated plastic material of the insulation includes a polyetherimide constituent and an additive system. The additive system includes an antioxidant/thermal stabilizer and a synergistic metal deactivator and may include a lubricant. For the jacket, the plastic material is a composition which may include a siloxane/polyimide copolymer constituent blended with a polyetherimide constituent and an additive system to improve processing and long term aging, or a siloxane/polyimide copolymer constituent with a flame retardant system.

Abstract: A tape-formed or sheet-formed insulating material for use in windings and coils of electrical machines includes an insulating layer in the form of a homogeneous film of an organic polymer or in the form of a felt of a paper of fibres of an organic polymer and a protective layer coated on at least one side of the insulating layer which protects the insulating layer against degradation caused by corona. The protective layer comprises an organic polymer containing at least 10 percent by volume of a powdered filler in the form of chromium oxide, iron oxide or a mixture of chromium oxide and iron oxide. The filler preferably has an intrinsic resistivity of 10.sup.4 -10.sup.8 ohm m. The thickness of the protective layer and the total thickness of the protective layer, respectively, are preferably smaller than the thickness of the insulating layer and the resistivity of the protective layer is preferably in excess of 10.sup.10 ohm m.

Abstract: Shaped articles of cross-linked polymers comprising a first component having little or no cross-linking and high elongation, and a second component having a relatively high level of cross-linking and low elongation. Such articles are particularly useful in the form of electrical insulation, the first component being adjacent to a wire or other conductor. Preferably each of the components comprises a crystalline fluorocarbon polymer, especially an ethylene/tetrafluoroethylene copolymer. Such articles can be prepared by (1) melt-extruding a first polymeric composition which contains little or no cross-linking agent, and a second polymeric composition which contains a greater amount of cross-linking agent, (2) maintaining the two extrudates under conditions such that cross-linking agent migrates from the second to the first composition, and (3) cross-linking both compositions, preferably by radiation.

Abstract: Coaxial electric cable and simplified process for making it, wherein large gauge center conductor is wrapped with extruded strands of porous expanded polytetrafluoroethylene, drawn through a die to reduce diameter and voids, tape-wrapped with porous expanded polytetrafluoroethylene, sintered, and shielding and extruded jacketing applied.

Abstract: A method of forming a colored coating film on a cross-linked polyethylene comprises coating a coloring paint prepared by blending a prepolymer having acryloyl and/or methacryloyl groups in the molecule, a monomer and/or oligmer having the above-mentioned groups in the molecule and a pigment on the surface of cross-linked polyethylene and then curing the paint under the irradiation of UV-rays.

Abstract: An extra-high-voltage power cable is provided with extruded insulation 3 over a conductor 1 thereof. The insulation comprises an inner layer 5 of an unfilled high density polyethylene or polypropylene material having a higher electric strength than the material of the insulation adjacent thereto in an outer layer 6 thereof.

Abstract: An electrical cable of conductive wire having an insulating layer of expanded, microporous sintered polytetrafluoroethylene around it, followed by a coating of a vinylidene fluoride-hexafluoropropylene copolymer surrounding the insulating layer, and an outer coating of polyvinylidene fluoride.

Abstract: A plenum cable (20) includes a core (22) comprising at least one transmission medium such as a metallic conductor. The metallic conductor is insulated with a layer (27) of a plastic composition of material which includes a non-halogenated constituent such as, for example, a polyetherimide. Covering the insulated metallic conductor is a jacket (39) comprising a halogenated material such as a fluoropolymer. The cable exhibits excellent flame retardant properties as well as acceptable levels of corrosion and toxicity.

Abstract: A stranded insulated wire and a method of producing the same. The stranded insulated wire is produced by applying a coating material containing polyvinyl butyral and a stabilized polyisocyanate to an enameled strands assembly and then by baking the assembly. The coating material contains about 1 to about 1000 parts by weight of the stabilized polyisocyanate per 100 parts by weight of the polyvinyl butyral.

Abstract: An electrical wire in which a core of stranded, insulated conductors is first coated with a thermoplastic resin layer having of melt index of at least 0.2 and then extrusion coated with a urethane resin layer. The urethane resin layer may be radiation cured.

Abstract: A curled electrical conductor cord is disclosed that comprises at least one core wire and a sheath layer covering the core wire, the core wire having at least one conductor covered with an insulating layer. The cord has a diameter of 1 mm or more, or has a cross-sectional area of 1 mm.sup.2 or more. The vertical stretch L.sub.0 of the curled portion of the cord by its own weight is 30% or less. The vertical stretch L.sub.50 of the curled portion of the cord under a load of 50 g is 200% or more.

Abstract: A high temperature and radiation resistant all polyimide insulated coaxial cable and process of manufacture. Perforated polyimide tape wrapping yields low dielectric constant cable.

Abstract: An electrical conductor is provided with an electrical insulation (11) surrounding the conductor (10) and a surrounding protective layer (12) which protects the insulation against degradation caused by corona. The protective layer consists of an organic polymer containing at least 10 percent by volume of a powdered filler in the form of chromium oxide, iron oxide, or a mixture of chromium oxide and iron oxide. The filler preferably has an intrinsic resistivity of 10.sup.4 -10.sup.8 ohm m. The thickness of the protective layer is preferably smaller than the thickness of the underlying insulation (11) and its resistivity preferably exceeds 10.sup.10 ohm m. The conductor is used, among other things, in windings and coils for electrical machines.

Abstract: Wire for repairing or changing circuit elements such as printed circuits, has heat-resistant insulation surrounded by a hot-melt adhesive. The wire is attached to the surface of printed circuit boards easily by applying a hot iron to the adhesive layer on the wire and melting the adhesive which then adheres to the board surface. The coating is applied by passing insulated wire vertically through a length of molten adhesive and then through a die. Printed circuit board modifications can be made quickly and easily and at a relatively low cost.

Abstract: A magnet wire enamel based on polyamide resins is disclosed in which the molecular weight of the polyamide resin is reduced through an equilibration reaction with a solvolytic agent and a titanate catalyst. Also disclosed is a method of applying said enamel to a magnet wire substrate and the resulting enameled magnet wire.

Abstract: Cordage (17) which may be used for any of the commonly marketed lengths of etractile cords comprises an array of a plurality of conductors (11--11) each insulated with a suitable plastic material. The array of conductors is enclosed in inner and outer jackets (52, 54). The inner jacket comprises a polyvinyl chloride (PVC) plastic material, for example, and has a thickness of about 0.015 inch. Covering the inner jacket is an outer jacket comprising a polyvinyl chloride plastic material having a thickness of about 0.005 inch and having a colorant constituent. The PVC composition of the inner jacket is such that it is a less expensive composition than that of the outer jacket. Enclosing the outer jacket is a layer (56) which comprises a top coating material. The top coating material provides the cordage with enhanced retractibility and prevents discoloration as well as plasticizer migration from the outer jacket.

Abstract: Flame retardant low smoke PVC-based thermoplastic compositions for use in wire insulation and cable jacketing. The compositions include poly(vinyl chloride), an additional chlorinated resin, tribasic lead sulfate, a molybdenum-containing smoke suppressing material, alumina trihydrate, a brominated aromatic ester plasticizer, at least one additional plasticizer, and at least one lubricant.

Abstract: The present invention is for a 180.degree. C. class heat activated magnet wire bondcoat comprising the invention product of(a) ##STR1## (b) R--CHO wherein R is an aliphatic moiety (c) R'--OH wherein R' is an aromatic moietyand the resulting composition has repeating units of the formula ##STR2## Additionally disclosed are methods for making said bondcoat and magnet wire coated with said bondcoat.

Abstract: Electrically insulated wire with an inner layer of non-crosslinked and non-crosslinkable polymeric material and a skin layer of irradiation crosslinked material compatible with the inner layer. The inner layer provides desirable flexibility and electrical insulating properties suitable for telecommunications cable and appliance wiring. The skin layer gives abrasion resistance suitable for the above purpose and heat resistance and fire retardance properties suitable for building wiring. The polymeric material of both layers is preferably of a polyvinylchloride composition.

Abstract: Improved electrical insulating tapes are disclosed having a poly(ethylene terephthalate) film component. The film has one amorphous surface and an opposite crystalline surface. In a preferred embodiment, a composite insulating material is provided having the film component with a fiber glass yarn strand layer adhered thereto. The fiber glass yarn strands are substantially continuous and uninterrupted, and are substantially parallel to the axis of elongation of the tape, and to each other.

Abstract: The termite repellent and/or the rodent repellent is entrapped in cyclodextrin as a cyclodextrin inclusion compound.The termite repellent may be: for example, a copper compound, such as copper naphthenate, or cuprous oxide; an organic phosphorus insecticide, such as chlorpyrifos, phoxim (i.e., phenylglyoxylonitriloxime O,O-diethyl phosphorothioate), fenitrothion, or prothiophos (CAS No. 34643-46-4); carbamate insecticide, such as carbaryl; pyrethroids insecticide, such as permethrin, or furamethrin.The rodent repellent may be: for example, cycloheximide, i.e., naramycin; or organic tin compound, such as dibutyltin oxide, or dibutyltin laurate.The cyclodextrin inclusion compound of termite repellent and/or rodent repellent and glycitols are mixed with a covering material of the electric wire or cable.The chief ingredient of the covering material is a synthetic resin or synthetic rubber. The synthetic resin may be polyvinyl chloride, or polyethylene.

Abstract: The invention relates to a hydroexpansible composite material, the method of preparing same and a composition for implementing this method, as well as to the uses thereof. The composite material includes a solid flat support having, on at least one of its faces, a coating with a high proportion of a hydroexpansible polymer powder fixed to the support by means of a hydrosoluble binder, the coating being essentially formed of:95 to 55% by weight of hydroexpansible polymer powder;5 to 23% by weight of hydrosoluble binder; and0 to 22% by weight of surfactant.This hydroexpansible material may advantageously be used in medicine, surgery agriculture and especially as sealing agent in cables, particularly electric cables.FIG. 2 shows how, in a cable, this material (11, 13) forms a sealing ring (13) about the point of infiltration of the water, thus preventing its longitudinal propagation.

Abstract: A heat-resistnat wire is disclosed which comprises a line of copper or aluminum coated with a shielding material obtained by heating a mixture of: (A) an ethylenic copolymer comprised of ethylene and 0.1 to 20.0 mol % of a monomer of at most 30 carbon atoms having an oxirane group or a hydroxyl group and having at least one double bond; and (B) an ethylenic copolymer comprised of ethylene and 0.1 to 20.0 mol % of a monomer possessing a functional group capable of reacting with oxirane group or hydroxy group in the ethylenic copolymer (A). The wire is excellent not only in heat resistance but also in insulating ability and flexibility.

Abstract: The present invention relates to a polymer composition exhibiting high temperature oil resistance, while having improved modulus and tensile strength, as well as a novel insulated electrical conductor employing such material, said material comprising a polymeric constituent selected from the group consisting of copolymers of ethylene and propylene, polymers of same with other polymerizable materials, and mixtures of the foregoing, said constituent being in intimate mixture with a fully calcined aluminum silicate clay filler containing less than about 0.5 percent by weight water (based on the weight of the clay) having an average particle size less than 1 micron with at least about 80 weight percent of the particles having size finer than 2 microns and with at least about 10 weight percent of the particles being more finely divided than 0.5 microns.

Abstract: A coil for arrangement in slots in a stator or rotor of an electrical machine, in particular a high voltage coil, comprising a bundle (17) of a plurality of conductors (18) located adjacent to each other and provided with a conductor insulation (19) for insulation of the conductors from each other as well as a main insulation (14) surrounding the bundle for insulation of the bundle against the machine slot. The main insulation consists of a wrapping of a tape- or sheet-formed insulating material wound in several layers around the bundle and comprising a layer with small mica flakes which, as well as the spaces between layers of mica flakes in the wrapping, contains a cured impregnating resin. At least that part of the impregnating resin located in the spaces between mica layers contains particles of a filler with an intrinsic thermal conductivity of at least 5 W/mK, such as aluminium oxide or boron nitride, and with a grain size of the particles of 0.1-15 .mu.m in at least 90 percent of the filler.

Abstract: The present invention relates to a polymer composition exhibiting high temperature oil resistance, while having improved modulus and tensile strength, as well as a novel insulated electrical conductor employing such material, said material comprising a polymeric constituent selected from the group consisting of copolymers of ethylene and propylene, polymers of same with other polymerizable materials, and mixtures of the foregoing, said constituent being in intimate mixture with from about 1 to about 150 parts by weight (per 100 parts by weight of polymer) of processing oil, and a calcined aluminum silicate clay filler containing less than about 0.5 percent by weight water (based on the weight of the clay) having an average particle size less than 1 micron with at least about 80 weight percent of the particles having size finer than 2 microns and with as much as 10 weight percent of the particles being more finely divided than 0.5 microns.

Abstract: An insulated conductor for high temperature use and methods of manufacture thereof. The conductor is insulated by at least three layers of insulation, the inner layer being made of a perfluoroalkoxy, a polytetrafluoroethylene, an ethylene-tetrafluoroethylene, or a fluorinated ethylene-propylene resin compound, the second layer being made of a polyimide resin compound and the third layer being made of perfluoroalkoxy, an ethylene-tetrafluoroethylene copolymer, a non-hydrolizing, thermoset polyamide or a polyvinylidene fluoride resin compound. The layers are coated or extruded over the conductor and each other and preferably, the first layer is etched before the second layer is applied.

Abstract: A method and apparatus for forming an electrically conductive externally insulated casing for an oil well of the type in which the casing carries electrical current to a primary heating electrode positioned downhole, using multiple prefabricated casing segments; each casing segment is a long steel pipe having a female thread coupling on one end and a male thread on the other end. Each segment has an insulator covering, over substantially all of its length, that has a figure of merit (erl)/.DELTA. of no more than 4.times.10.sup.8 so that the shunt impedance of the casing to ground can be kept substantially greater than the spreading resistance of the primary heating electrode. The preferred casing segment insulation is in two layers, including a hard, durarable inner layer subject to water degradation and an outer water-impervious layer usually applied as tape.

Abstract: A flat multi-conductor power cable is disclosed which includes a plurality of generally parallel, spaced apart, flat conductors which are surrounded by two layers of insulation material. An internal layer is extruded around each of the flat conductors and is intimately bonded to each conductor. A single external layer is extruded around all of the internal layers and is intimately joined to all of the internal layers. Preferably, the external layer comprises a thermoplastic elastomer and the internal layer comprises a polyolefinic ionomer. A method and apparatus for making such a flat multi-conductor power cable is also disclosed.

Abstract: An insulated electrical cable is disclosed, comprising an electrical conductor coated with an insulating layer comprising an ethylene/.alpha.-olefin copolymer having a density of from 0.89 to 0.91 and an ethylene/vinyl acetate copolymer.

Abstract: A fluorine-containing elastomeric electric insulating material is disclosed. The material is a vulcanized product of a composition comprising 100 parts by weight of a fluorine-containing elastomeric copolymer having a number average molecular weight of from 20,000 to 60,000, containing as major components a unit based on tetrafluoroethylene and a unit based on an .alpha.-olefin having 2 to 4 carbon atoms and exhibiting rubber elasticity at room temperature, 0.1 to 5 parts by weight of an organic peroxide and 0.1 to 20 parts by weight of a polyallyl compound.

Abstract: A laminated construction comprising at least three extruded layers of polymer-based material in which an intermediate layer (4) between a first layer (3) and a second layer (5) is strippably bonded to the first layer (3) and fully bonded to the second layer (5) such that the second layer together with substantially all of the intermediate layer (4) is readily strippable from the first layer (3). In particular, the invention relates to an insulated electrical cable in which such a laminated construction is arranged substantially coaxially about a core conductor (1); the first layer (3) being an inner layer of insulating material, intermediate layer (4) being either of insulating material or of a semi-coductive shielding material and the second layer (5) being an outer layer of a semi-conductive shielding material. Preferably, an additional layer of semi-condutive shielding material is positioned between the core conductor (1) and the first layer (3).

Abstract: A submersible motor having a primary winding made of a water-tight wire has an improved life characteristic. The water-tight wire is made of a conductor and three layers formed on the conductor. The three layers are a heat-resistant enamel layer, a main insulating layer and an outer protective layer. The main insulating layer is composed of crosslinked polyethylene or a polypropylene. The outer protective layer is composed of a polyvinyl chloride composition having as a base material a polyvinyl chloride having a number average polymerization degree of 2000 or higher.

Abstract: An insulated conductor for a wire harness comprising a conductor and an insulation with which the conductor is covered, the insulation being formed of thermoplastic polyurethane having shore D hardness of more than 50, thickness of less than 0.2 mm, and an adherence of the insulation to the conductor less than 2 Kg/10 mm, being measured as the required force to pull 10 mm of the insulation off the conductor.

Abstract: In an excellent windability magnet wire wherein an insulating layer of a synthetic resin film is formed on a conductor directly or with another insulation in between and a lubricant layer is formed on the insulating layer, the lubricant layer is made of an intimate mixture of natural wax as a major constituent and thermosetting and fluorocarbon resins compounded therewith.

Abstract: This invention relates to the use of ethylene/tetrafluoroethylene (ETFE) or ethylene/chlorotrifluoroethylene (ECTFE) polymers to produce a foamed coating of insulation over wire and used as wire pairs for transmitting electronic signals, in which the foamed coating is surrounded by a protective jacket or skin made of one of the two polymers.