A multilayer electric field grading article comprises first and second layers forming a discrete interface. The first layer comprises a first electric field grading composition comprising first particles dispersed in a first matrix material. The second layer comprises a second electric field grading composition comprising second particles, compositionally different than the first particles, dispersed in a second matrix material. The first and second layers have respective first and second degrees of nonlinearity between respective first and second onset voltages and corresponding first and second breakdown voltages. The first and second layers taken together have a combined onset voltage that is higher than the first and second onset voltages, and the first and second layers taken together have a greater combined degree of nonlinearity than each of the first and second degrees of nonlinearity taken individually. A method of reducing electric field stress at a joint or termination of a substrate includes applying the multilayer electric field grading article to a surface of a substrate.

An insulation or jacket layer for a coated conductor is composed of (A) a crosslinked silane- functional polyolefin, (B) a filler composed of greater than 50 wt % silica, based on the total weight of the filler, (C) a silicone-containing polymer selected from the group consisting of reactive linear silicone-containing polymers, non-reactive linear silicone-containing polymers, and non-reactive branched silicone-containing polymers, and (D) from 0.00 wt % to 20 wt % of a silanol condensation catalyst, based on the total weight of the insulation or jacket layer.

An insulated electrical cable according to one aspect of the present invention is an insulated electrical cable including: a conductor; and an insulating layer that is laminated on an outer peripheral surface of the conductor and includes a polyimide as a main component, wherein the insulating layer includes a plurality of pores, and wherein a porosity of the insulating layer is greater than or equal to 25% by volume and less than or equal to 60% by volume.

Provided is a direct-current (DC) power cable. Specifically, the present invention relates to a DC power cable capable of preventing both a decrease in DC dielectric strength and a decrease in impulse breakdown strength due to space charge accumulation, and reducing manufacturing costs without lowering the extrudability of an insulating layer and the like.

The direct-current cable includes a conductive portion; and an insulating layer covering an outer periphery of the conductive portion, the insulating layer containing cross-linked base resin and inorganic filler, the base resin containing polyethylene, a BET specific surface area of the inorganic filler being greater than or equal to 5 m.sup.2/g and less than or equal to 150 m.sup.2/g, and a mean volume diameter of the inorganic filler being less than or equal to 1.0 m, the mass ratio of the inorganic filler with respect to the base resin being greater than or equal to 0.001 and less than or equal to 0.05, and the cross-linked base resin being cross-linked by a cross-linking agent containing organic peroxide.

The invention relates to an electrical cable (1) for an appliance, especially a vacuum cleaner. The cable (1) comprises a core bundle (21) comprising two core wires (10), each of the two core wires (10) comprising a center conductor (11) made of conductive strands and an insulation layer (13) on the outer periphery of the center conductor (11), the insulation layer (13) comprising a non-foamed softened polyvinyl chloride compound an inner sheath layer (14) arranged around the insulation layers (13), the inner sheath layer (14) comprising a foamed softened polyvinyl chloride compound wherein the foamed softened polyvinyl chloride compound of the inner sheath layer (14) contains a plurality of cells (16) and wherein each cell (16) is characterized by an equivalent diameter, in particular the diameter of a sphere having the same volume as the cell (16), an outer sheath layer (15) arranged around the inner sheath layer (14), the outer sheath layer (15) comprising a non-foamed, softened polyvinyl chloride compound. The invention further relates to an appliance with such a cable (1) as well as to an method of manufacturing the cable (1).

An electric wire includes a conductor, and an insulating film that is configured to cover the conductor and that includes a porous layer having a porous therein, and a non-porous layer in which no porous is formed, wherein the non-porous layer is disposed as an outermost layer of the insulating film.

Provided is a cable device including an optical cable capable of power transmission and a connector coupled with the optical cable, and having improved electromagnetic shielding performance. The cable device includes a cable; and a connector coupled to the cable, wherein the connector includes a printed circuit board (PCB) including a ground electrode, a shield case provided to accommodate the PCB and include a first face facing a mounting surface of the PCB and a second face perpendicular to the first face, and an elastic member arranged between the PCB and the shield case and provided to contact the ground electrode and the second face of the shield case so as to ground the shield case.

A method of enhancing surface electrical conductivity of an article formed of a conductive polymer material, such as a conductive polymer film, includes the step of providing an article formed of a conductive polymer. The conductive polymer is made up of a dielectric polymeric material and conductive fibers. A desired pressure is applied to at least a portion of the article while simultaneously heating at least a portion of the article to a desired temperature. The desired pressure and the desired temperature are maintained on at least a portion of the article for a desired time period. This method reduces a polymer-rich skin layer on the surface of the conductive polymer material and helps to randomize the orientation of the conductive fibers on the surface.

An example method includes: (i) depositing an insulating layer on a substrate; (ii) forming a conductive polymer layer on the insulating layer; and (iii) repeating deposition of a respective insulating layer, and formation of a respective conductive polymer layer to form a multilayer stack of respective conductive polymer layers interposed between respective insulating layers. Each respective conductive polymer layer has a respective electrical resistance, such that when the respective conductive polymer layers are connected in parallel to a power source, a resultant electrical resistance of the respective conductive polymer layers is less than each respective electrical resistance.