The present application discloses a composition comprising: (1) a polyvinyl chloride polymer; (2) a plasticizer according to formula I:

##STR00001##

wherein R.sup.1, and R.sup.2 are described herein. The composition when formed into insulation layers for wire and cable insulation provides excellent heat stability (e.g., tensile strength and elongation at break retention). The present application further provides insulation layers formed from the composition of the present invention. The present application further provides cables that include a conductor and an insulation layer surrounding at least some of the conductor, the insulation layer being formed from the compositions of the present invention.

A highly bendable insulated electric wire including: a conducting wire formed by stranding a plurality of metal strands; and an insulator covering the conducting wire, in which a twist pitch ratio of the conducting wire (a twist pitch/an outer diameter of the conducting wire) is 10.8 or less, the insulator is made of a resin composition containing a vinyl chloride resin and having an elongation rate of 130% or higher at 40 C., and an adhesion strength between the conducting wire and the insulator is 20 N or less.

Aspects of the present invention relate to reinforced electric wires, particularly reinforced electric wires as used in holiday lighting such as Christmas light strings. In some embodiments, the reinforced electric wire can comprise a conductor, a reinforcing string or one or more reinforcing threads, and an insulator jacket. In some embodiments, the conductor comprises a single conductor strand. In some embodiments, the conductor comprises a plurality of conductor strands. In some embodiments, the wire comprises an insulator jacket having a plurality of channels therein, where a conductor is passed through the center channel, and reinforcing threads are passed through the other channels. Methods of making wires in accordance with various embodiments are also provided herein.

An aluminum electrical wire includes a conductor including aluminum-based core wires, and an insulating resin covering covering the conductor and having a thickness deviation of not less than 70%. The aluminum-based core wires contain 99 mass % of aluminum, and the conductor is constructed by concentrically twisting 19 or 37 of the aluminum-based core wires at the same pitch in a non-compressed state such that the aluminum electrical wire has a current capacity that is substantially the same as a current capacity of a copper electrical wire having a diameter that is substantially the same as a diameter of the aluminum electrical wire.

A cable includes at least one core that has a conductor and an insulating coating layer that covers the conductor; and a sheath layer that covers the at least one core. The sheath layer includes an inner sheath layer and an outer sheath layer that covers the inner sheath layer. The inner sheath layer contains a silane-crosslinked very low density polyethylene. A main component of the outer sheath layer is polyurethane; a content of the very low density polyethylene per 100 parts by mass of a resin component in the inner sheath layer is 20 parts by mass or more and 100 parts by mass or less. A content of silicon atoms constituting silane crosslinks in the very low density polyethylene is 0.05 mass % or more and 1 mass % or less.

A flame retardant compound is provided. The flame retardant compound includes a polymer base resin, a carbonific host compound, and a guest compound including at least one atom of a transition metal. The carbonific host compound and the guest compound form a host-guest complex, and the host-guest complex acts to inhibit at least one of smoke release and smoke formation when exposed to heat. The host-guest complex is distributed within the polymer base resin. An intumescent flame retardant compound is also provided. The intumescent flame retardant compound includes a base resin, an acid donor, a spumific agent, a cyclodextrin host compound, and a guest compound including at least one atom of molybdenum. The cyclodextrin host compound and the guest compound form a host-guest complex. The acid donor, carbonific host compound, and spumific agent react when exposed to a temperature above 280 C. to form a foam.

A signal cable structure includes a set of strands, an outer insulation tube and a water swellable powder. The set of strands includes a plurality of twisted pairs. The twisted pairs are enclosed to form a center portion, and each of the twisted pairs includes two wires intertwined with each other. The outer insulation tube sheaths the set of strands; an outer ring portion is surrounded outside the set of strands and formed between the outer insulation tube and the set of strands. The water swellable powder is distributed in the outer ring portion, and the center portion of the set of strands is not distributed with the water swellable powder. Thereby, a signal cable with waterproof performance is provided.

Reinforced electric wires, particularly reinforced electric wires as used in holiday lighting such as Christmas light strings are disclosed. In some embodiments, the reinforced electric wire has a conductor, a reinforcing string or one or more reinforcing threads, and an insulator jacket. In some embodiments, the conductor has a single conductor strand. In some embodiments, the conductor has a plurality of conductor strands. In some embodiments, the wire has an insulator jacket having a plurality of channels therein, where a conductor is passed through the center channel, and reinforcing threads are passed through the other channels.

A flame retardant compound is provided. The flame retardant compound includes a polymer base resin, a carbonific host compound, and a guest compound including at least one atom of a transition metal. The carbonific host compound and the guest compound form a host-guest complex, and the host-guest complex acts to inhibit at least one of smoke release and smoke formation when exposed to heat. The host-guest complex is distributed within the polymer base resin. An intumescent flame retardant compound is also provided. The intumescent flame retardant compound includes a base resin, an acid donor, a spumific agent, a cyclodextrin host compound, and a guest compound including at least one atom of molybdenum. The cyclodextrin host compound and the guest compound form a host-guest complex. The acid donor, carbonific host compound, and spumific agent react when exposed to a temperature above 280 C. to form a foam.

Disclosed are cable types, including a type THHN cable, the cable types having a reduced surface coefficient of friction, and the method of manufacture thereof, in which the central conductor core and insulating layer are surrounded by a material containing nylon or thermosetting resin. A silicone based pulling lubricant for said cable, or alternatively, erucamide or stearyl erucamide for small cable gauge wire, is incorporated, by alternate methods, with the resin material from which the outer sheath is extruded, and is effective to reduce the required pulling force between the formed cable and a conduit during installation.