Hitachi Metals, Ltd.

Mitsuru Hashimoto

Makoto Iwasaki

Ryutaro Kikuchi

Hiroshi Okikawa

Tamotsu Kibe

Takuya Oriuchi

Yoshiaki Nakamura

Hiroshi Nakashima

Akinari Nakayama

Kenichiro Fujimoto

Motoharu Kajiyama

Mamoru Ohashi

Kohei Arita

A non-halogen flame-retardant insulated electric wire includes a conductor and a crosslinked single-layer or a multilayer insulating layer on an outer periphery of the conductor. The insulating layer has a tensile elastic modulus of 500 MPa or more and an elongation at break of 120% or less in a tensile test performed at a displacement rate of 200 mm/min, and has a storage elastic modulus at 125&#xb0; C. of 3&#xd7;10Pa or more in a dynamic viscoelasticity test.

Non-halogen flame-retardant insulated electric wire and non-halogen flame-retardant cable

A multilayer insulated wire includes a conductor, an inner insulation layer, and an outer insulation layer. A gel fraction of the inner insulation layer defined below is not less than 80%. A gel fraction of the outer insulation layer defined below is less than the gel fraction of the inner insulation layer and not less than 75%. An insulation covering layer including the inner and outer insulation layers is cross-linked and has a tensile modulus of not less than 500 MPa in a tensile test conducted at a tensile rate of 200 mm/min. Gel fraction (%)=(mass of inner or outer insulation layer after being immersed in xylene at 110&#xb0; C. for 24 hours, then left at 20&#xb0; C. and atmospheric pressure for 3 hours and vacuum-dried at 80&#xb0; C. for 4 hours/mass of inner or outer insulation layer before immersion in xylene)&#xd7;100

Multilayer insulated wire and multilayer insulated cable

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 non-halogen flame-retardant insulated electric wire and a non-halogen flame-retardant cable that have excellent abrasion resistance, terminal processability, and handling ease in a high-temperature environment are provided. A non-halogen flame-retardant insulated electric wire includes a conductor and a crosslinked single-layer or multilayer insulating layer on an outer periphery of the conductor. The insulating layer has a tensile elastic modulus of 500 MPa or more and an elongation at break of 120% or less in a tensile test performed at a displacement rate of 200 mm/min, and has a storage elastic modulus at 125&#xb0; C. of 3&#xd7;10Pa or more in a dynamic viscoelasticity test.

A non-halogen insulating wire with excellent flame resistance as well as high mechanical characteristics (wear resistance) and electrical insulation characteristics is provided. A non-halogen two-layer insulating wire includes: a conductor; and an insulating layer having an insulating inner layer which covers an outer circumference of the conductor and an insulating outer layer which covers an outer circumference of the insulating inner layer. The insulating inner layer is made of a first non-halogen resin composition which contains metal hydroxide and a base polymer (A) including polyolefin, and has a thickness of 20% to 58% of an entire thickness of the insulating layer. The insulating outer layer is made of a second non-halogen resin composition which contains metal hydroxide and a base polymer (B) including polyester resin and/or polyester elastomer resin.

Non-halogen multilayer insulating wire

An insulated wire includes a conductor, and an insulation layer provided around the conductor. The insulation layer includes an inner layer located on a conductor side and an outer layer provided around the inner layer. The inner layer includes a halogen-free resin composition including a base polymer (A). The outer layer includes a cross-linked body obtained by cross-linking a halogen-free flame-retardant resin composition including a base polymer (B) and a halogen-free flame retardant. The base polymer (A) includes a thermoplastic resin (a1) having an aromatic ring in a backbone chain. The base polymer (B) includes a polyolefin component. A thickness of the inner layer is not less than 0.03 mm and not more than 70% of a thickness of the insulation layer.

Insulated wire and cable

A crosslinkable halogen-free resin composition includes a polymer blend, and a metal hydroxide mixed in an amount of 120 to 200 parts by mass per 100 parts by mass of the polymer blend. The polymer blend includes a high-density polyethylene, 30 to 50 parts by mass of an ethylene-acrylic ester-maleic anhydride terpolymer, 5 to 20 parts by mass of a maleic anhydride modified ethylene-&#x3b1;-olefin copolymer and 10 to 30 parts by mass of an ethylene-vinyl acetate copolymer.

Crosslinkable halogen-free resin composition, cross-linked insulated wire and cable

A crosslinkable halogen-free resin composition includes a polymer blend, and a metal hydroxide mixed in an amount of 120 to 200 parts by mass per 100 parts by mass of the polymer blend. The polymer blend includes a maleic anhydride-modified high-density polyethylene, 30 to 50 parts by mass of an ethylene-acrylic ester-maleic anhydride terpolymer, 5 to 20 parts by mass of a maleic anhydride modified ethylene-&#x3b1;-olefin copolymer and 10 to 30 parts by mass of an ethylene-acrylic ester copolymer.

A halogen-free crosslinkable resin composition includes a base polymer including a high density polyethylene, 30 to 50 parts by mass of an ethylene-acrylic ester-maleic anhydride terpolymer, 5 to 20 parts by mass of an ethylene-&#x3b1;-olefin copolymer modified with maleic anhydride, and 10 to 30 parts by mass of an ethylene-acrylic ester copolymer, and a metal hydroxide of which content is 120 to 200 parts by mass based on 100 parts by mass of the base polymer.

Halogen-free crosslinkable resin composition, cross-linked insulation wire and cable

A non-halogen multilayer insulated wire includes a conductor, an inner layer covering the conductor, and an outer layer formed on the external surface of the inner layer. The inner layer includes a polyolefin resin composition including 60 to 95 parts by mass of a high density polyethylene, 5 to 40 parts by mass of an ethylene copolymer, and 0.1 to 1 part by mass of a metal damage inhibitor. The outer layer includes a polyester resin composition that includes a base polymer mainly including a polyester resin, and further includes, relative to 100 parts by mass of the base polymer, 50 to 150 parts by mass of a polyester block copolymer, 0.5 to 5 parts by mass of a hydrolysis inhibitor, 0.5 to 5 parts by mass of an inorganic porous filler, and 10 to 30 parts by mass of magnesium hydroxide.

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Hitachi, Japan

Mitsuru Hashimoto