Hitachi Metals, Ltd.

Proterial, Ltd.

Motoharu Kajiyama

Tamotsu Kibe

Makoto Iwasaki

Yoshiaki Nakamura

Masafumi Kaga

Kentaro Segawa

Mamoru Ohashi

Hiroshi Okikawa

Akinari Nakayama

Mitsuru Hashimoto

Hajime Nishi

Takayuki Tanaka

Masanobu Nakahashi

An insulated electric wire is composed of a conductor, and a covering layer disposed around an outer circumference of the conductor. The covering layer has a plurality of flame retardant layers composed of a flame retardant resin composition, and an insulating layer interposed between the plurality of flame retardant layers. The insulating layer is made of a resin composition including a resin component, and the resin component includes 40% by mass or more of a resin having a melting point of 125 degrees C. or higher of 100% by mass of the resin component.

Insulated electric wire

An insulated wire includes a conductor, and a flame-retardant insulation layer that includes a resin composition including a flame retardant and is arranged around the conductor, and a water-blocking layer that is arranged around the flame-retardant insulation layer and has a water absorption of not more than 0.5% at saturation. The thickness of the water-blocking layer is not less than 25 &#x3bc;m.

Insulated wire

A LAN cable includes an insulated electrical wire having an insulating layer on an outer periphery of a conductor, a sheath that coats an outer periphery of the insulated electrical wire, and an intermediate layer arranged between the sheath and the insulated electrical wire, the intermediate layer having a mass reduction rate at 800&#xb0; C. of less than or equal to 80% by mass. The sheath includes a cross-linked matter or a non-halogen flame retardant resin composition in which a mass reduction rate at 800&#xb0; C. is less than or equal to 60% by mass.

LAN cable

A LAN cable includes a sheath; an electrical wire accommodated in the sheath and including a conductor and an insulating body covering the conductor; and an intermediate layer having a mass reduction rate at 500.degree. C. of less than or equal to 10% by mass and a mass reduction rate at 600.degree. C. of less than or equal to 50% by mass, and located between the sheath and the electrical wire. The insulating body includes polyethylene having a dielectric constant of smaller than or equal to 2.5. The sheath includes a polyolefin-based polymer and a flame retardant, and a content of the flame retardant in the sheath is greater than or equal to 150 parts by mass with respect to 100 parts by mass of the polyolefin-based polymer.

A cable includes a conductor, an insulation coating layer on the conductor, and an outer coating layer on the insulation coating layer. The insulation coating layer is made of a composition containing 100 parts by mass of a base polymer (A) and 100 to 250 parts by mass of a non-halogen flame retardant. The polymer (A) contains 70% to 99% by mass of an ethylene-vinyl acetate copolymer (a1) containing an ethylene-vinyl acetate copolymer having a melting point of 70&#xb0; C. or higher, and 1% to 30% by mass of an acid-modified polyolefin resin (a2) having a glass transition point of &#x2212;55&#xb0; C. or lower. The polymer (A) contains 25% to 50% by mass of a vinyl acetate component derived from the copolymer (a1). The outer coating layer is made of a composition containing 100 parts by mass of a base polymer (B) and 150 to 220 parts by mass of a non-halogen flame retardant. The polymer (B) contains 60% to 70% by mass of a linear low-density polyethylene (b1), 10% by mass or more of an ethylene-vinyl acetate copolymer (b2) having a melt flow rate of 100 g/10 min or more, and 10% to 20% by mass of a maleic acid-modified polyolefin (b3).

Cable

A phosphorus-free based halogen-free flame-retardant resin composition includes a base polymer including a copolymer of ethylene and &#x3b1;-olefin having carbon number of 3 to 8 polymerized by a metallocene catalyst as a main component, and 5 to 30 weight % of an ethylene-vinyl acetate copolymer that has a melt flow rate of not less than 50 g/min and a vinyl acetate content of not less than 40%, a metal hydroxide blended with the base polymer in a ratio of 100 to 250 parts by weight relative to 100 parts by weight of the base polymer, and a mineral oil blended with the base polymer in a ratio of 1 to 20 parts by weight relative to 100 parts by weight of the base polymer.

Phosphorus-free based halogen-free flame-retardant resin composition, phosphorus-free based halogen-free flame-retardant insulated electric wire and phosphorus-free based halogen-free flame-retardant cable

A non-halogen flame-retardant insulated wire includes a conductor and an insulating coating layer including an inner layer and an outer layer. The inner layer includes a composition in which 50 to 95 parts by weight of a polyethylene with a density of 0.930 g/cmor more and 5 to 50 parts by weight of an ethylene copolymer are mixed. The outer layer has a composition including a base polymer in which 60 to 95 parts by weight of an ethylene-vinyl acetate copolymer containing 60% by weight or more of vinyl acetate and 5 to 40 parts by weight of a maleic acid-modified ethylene-&#x3b1;-olefin copolymer are mixed, and including 80 to 200 parts by weight of a metal hydroxide. The outer layer resin composition is crosslinked.

Non-halogen flame-retardant insulated wire

A halogen-free extra-high-voltage cable for railway rolling stock includes a stranded conductor, an inner semi-conducting layer covering the stranded conductor, an outer semi-conducting layer provided on an outer periphery of the inner semi-conducting layer via an insulation layer, and a sheath layer on an outer periphery of the outer semi-conducting layer, the sheath layer containing 80 to 200 parts by weight of metal hydroxide and 0.5 to 10 parts by weight of cross-linking agent with respect to 100 parts by weight of olefin-based polymer containing ethylene-vinyl acetate copolymer as a main component, the ethylene-vinyl acetate copolymer having a vinyl acetate content of not less than 40 wt % and less than 50 wt % and a melt flow rate of not more than 2.5 g/10 min and a resin composition is cross-linked.

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Takahagi, Japan

Motoharu Kajiyama