The present disclosure relates to a telecommunications cable. The telecommunication cable includes a plurality of twisted pairs of insulated wires extending substantially along a longitudinal axis of the telecommunications cable. Each insulated wire of the plurality of twisted pairs of insulated wires includes a conductor and an insulation surrounding the conductor. The insulation includes a first insulation layer defining a plurality of channels disposed around a peripheral surface of the conductor. In addition, the insulation includes a second insulation layer disposed circumferentially around the first insulation layer. Moreover, the insulation includes a third insulation layer disposed circumferentially around the second insulation layer. Furthermore, the telecommunication cable includes a separator and a first layer defining the outer jacket of the telecommunication cable.

The present invention provides a polypropylene cable protective layer and a preparation method thereof. The polypropylene cable protective layer sequentially includes a dielectric layer, a buffer layer and an insulating layer from the inside to the outside, and the thickness of the dielectric layer accounts for 5%?12% of the thickness of the polypropylene cable protective layer; the thickness of the buffer layer accounts for 17%?25% of the thickness of the polypropylene cable protective layer; the dielectric layer, the buffer layer and the insulating layer are respectively obtained by the wrapping of a polypropylene film A, a polypropylene film B and a polypropylene film C. The polypropylene cable protective layer of the present invention forms a dielectric gradient, and realizes the improvement of the insulation strength and voltage level of the power cable, and the increase of the transmission capability.

A communication cable includes an insulation electric wire including a conductor having tensile strength of 400 MPa or more and a cross-sectional area of 0.22 mm.sup.2 or less and a covering layer covering the conductor and being formed of an insulating material, and a sheath covering an outer periphery of the insulation electric wire and being formed of a resin composition containing crystalline polyolefin. A tensile elastic modulus of the sheath is 500 MPa or less, and a mass increase rate of the sheath is less than 50 mass % in a plasticizer migration test involving exposure in an atmosphere at 105? C. for 3,000 hours. Characteristic impedance of the communication cable is 100?10?.

In an insulated wire including a conductor formed into a long shape and an insulation film formed by stacking at least one insulating layer covering a circumference of the conductor, the insulating layer includes a porous region and a resin region. The porous region is formed of a resin and multiple voids, and the resin region is formed of the resin. In the insulating layer, a boundary surface is not provided between a first boundary surface located on a radially inner side and a second boundary surface located on a radially outer side, and the porous region and the resin region are arranged in this order from the first boundary surface toward the second boundary surface.

A composite wire includes a metal inner core, an easily-passivated metal layer wrapping a surface of the metal inner core, and a self-adhesive resin layer wrapping a surface of the easily-passivated metal layer. An insulation layer of the composite wire is a metal passivation layer that is formed by the easily-passivated metal layer obtained after sintering treatment and oxidation. The preparation method is used for manufacturing the composite wire. The method for preparing a power inductor is used for preparing a new type of power inductor including the composite wire. The composite wire is high-temperature resistant and is easily wound. During winding, the easily-passivated metal layer is unlikely to fall off, thereby ensuring that the insulation layer formed by passivation of the easily-passivated metal layer has desirable weather resistance and voltage resistance.

A communication cable that has a reduced diameter while ensuring a required magnitude of characteristic impedance. The communication cable contains a twisted pair that contains a pair of insulated wires, twisted with each other and a sheath covering the twisted pair. Each of the insulated wires, contains a conductor that has a tensile strength of 400 MPa or higher and an insulation coating that covers the conductor. The sheath is made of an insulating material having a dielectric tangent of 0.0001 or higher. The communication cable 1 has a characteristic impedance of 10010.

A submarine power cable is provided having stranded conductor(s) and an insulation system, each individual stranded conductor, at given intervals, being compressed across an area to form a plurality of watertight partitions along a length of the of the submarine power cable. A method provides a plurality of watertight partitions along a length of the submarine power cable. The method includes, at a given point, arranging a compression tool around an outer circumference of the stranded conductor, using the compression tool to compress the stranded conductor, releasing the compression tool from the stranded conductor, and repeating the compression at a number of different points and using the compression tool to compress the stranded conductor at each of these points, thereby forming a plurality of watertight partitions along the length of the submarine power cable.

An insulated winding wire may include a conductor and insulation formed around the conductor. The insulation may include a base insulation layer formed around the conductor and having a first dielectric constant (1). The insulation may further include an extruded thermoplastic layer formed around the base insulation layer and having a second dielectric constant (2). The extruded thermoplastic layer may include (i) at least one polymer comprising a ketone group and (ii) at least one fluoropolymer. A ratio of the dielectric constant (2) of the extruded thermoplastic layer to the dielectric constant (1) of the base layer at 250 C. may be less than or equal to approximately 1.0.

An insulated wire includes a core body comprising electrically-conductive material. The insulated wire also includes a permanent coating comprising electrically-insulating material and disposed on the core body to electrically insulate the core body. The insulated wire further includes a removable coating disposed on the permanent coating to provide the core body and the permanent coating with structural support during cutting of the core body and the permanent coating to the desired length.

An electric wire is disclosed having a metal conductor, a first synthetic heat stable tape layer in direct contact with the metal conductor, wherein the first synthetic heat stable tape layer has a first edge and a second edge, wherein the first edge and the second edge are substantially parallel to one another, wherein the second edge overlaps the first edge by at least 180 degrees on a cross-sectional view, a second synthetic heat stable tape layer, wherein the second synthetic heat stable tape layer is helically wrapped around the first synthetic heat stable layer, a third synthetic heat stable tape layer, wherein the third synthetic heat stable tape layer is helically wrapped around the second synthetic heat stable layer, wherein electric wire contains no silicone, and an extruded layer, wherein the extruded layer is extruded over the second synthetic heat stable tape layer.