JP5330660B2 - Insulated wires with excellent weather resistance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an insulated electric cable which has superior mechanical characteristics and thermal resistance or the like and has both an excellent fire resistance conforming to a severe fire resistance regulation and a high weatherability. <P>SOLUTION: In an insulated electric cable composed of a multilayer coating structure, the insulated electric cable has a coating layer consisting of a resin composition (B) which contains magnesium hydroxide 150-360 parts by mass and melamine cyanurate 0-90 parts by mass against a resin component (a) having ethylenic copolymer and polyolefin resin and/or styrenic elastomer as a main component 100 parts by mass and further, in the resin component (a) of the resin composition, the total of a vinyl acetate quantity of ethylenic copolymer and (meth) acrylic ester, (meth) acrylic acid and unsaturated carboxylic acid component is 36-70 mass% in the resin component, coated on the outside of a coating layer consisting of a fire resistant resin composition (A) which contains a metal hydrate 40-200 parts by mass and melamine cyanurate 0-90 parts by mass against the resin component (a) having ethylenic copolymer and polyolefin resin and/or styrenic elastomer as a main component 100 parts by mass. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an insulated wire coated with a flame-retardant insulating resin composition that is free from elution of heavy metal compounds, generation of a large amount of smoke and corrosive gas at the time of disposal such as landfill and incineration. The present invention relates to an insulated wire coated with an insulating resin composition having excellent properties.

Insulated wires used for internal and external wiring of electrical / electronic devices are required to have various properties such as flame retardancy, tensile properties, and heat resistance. For this reason, as a covering material for these insulated wires, a resin composition mainly composed of an ethylene-based copolymer containing a polyvinyl chloride (PVC) compound or a halogen-based flame retardant containing a bromine atom or a chlorine atom in the molecule. It is well known to use things.
However, various problems have been raised when an insulated wire using such a coating material is discarded without appropriate treatment. For example, when discarded by landfill, elution of plasticizers and heavy metal stabilizers blended in the coating material, and when incinerated, problems such as generation of a large amount of corrosive gas and generation of dioxins occur. . For this reason, studies are being actively conducted on techniques for coating electric wires with non-halogen flame retardant materials that do not generate harmful heavy metals or halogen-based gases.

Conventional non-halogen flame retardant materials are those in which flame retardancy is expressed by blending a flame retardant containing no halogen with a resin. Examples of flame retardants for such coating materials include magnesium hydroxide, water Metal compounds having a hydroxyl group or crystal water, such as aluminum oxide, and the resin include polyethylene, ethylene-1-butene copolymer, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid. Ethyl copolymers, ethylene-propylene-diene terpolymers, and the like are used (see, for example, Patent Document 1).
JP 2001-60414 A

  In order to ensure the above flame retardancy, the non-halogen flame retardant material retains the flame retardancy by adding the same amount or more of magnesium hydroxide to the above resin component. However, such a resin composition containing a large amount of magnesium hydroxide and an electric wire using the resin composition are remarkably poor in weather resistance, and cannot be used outdoors or for lighting wiring. So far, when using electric wires and cables coated with non-halogen flame retardant materials outdoors, we have used carbon to increase the weather resistance, but when performing various wiring such as lighting system wiring, It is indispensable to increase the number of colors of the electric wires, and there is a problem that non-halogen electric wires cannot be used in such a region.

In addition, electronic wire harnesses used in electronic equipment are required to have high flame resistance from the viewpoint of safety. For example, the F mark is stipulated in the very strict flame retardant standard Electrical Appliance and Material Safety Law. It must clear the VW-1 standard of the vertical flame test specified (Vertical Flame Test) and the 60 degree inclined flame retardant characteristic specified in JISC3005.
The present invention solves the above-mentioned problems, and provides an insulated wire having excellent mechanical properties, heat resistance, etc. and having both excellent flame resistance and high weather resistance conforming to strict flame resistance standards. With the goal.

As a result of intensive studies, the present inventors have found that a non-halogen electric wire capable of maintaining high weather resistance can be obtained by using an insulated wire having a specific multilayer coating structure. In addition, by controlling the surface treatment agent and resin component of magnesium hydroxide, we succeeded in maintaining even higher weather resistance.
That is, the present invention is (1) in an insulated wire having a multi-layer coating structure, with respect to 100 parts by mass of an ethylene copolymer and a resin component (a) mainly composed of a polyolefin resin and / or a styrene elastomer, a hydroxyl group or crystal water. A flame retardant resin composition containing 40 to 200 parts by mass of a metal compound having a part and all of the metal compound being aluminum hydroxide and 0 to 90 parts by mass of melamine cyanurate (A ) Outside the coating layer,
150 to 360 parts by weight of magnesium hydroxide and 0 to 90 parts by weight of melamine cyanurate are contained with respect to 100 parts by weight of the resin component (a) mainly composed of an ethylene copolymer and a polyolefin resin and / or a styrene elastomer. In addition, in the resin component (a) in the resin composition, the total amount of vinyl acetate, (meth) acrylic acid ester, (meth) acrylic acid and unsaturated carboxylic acid component of the ethylene copolymer component is the resin component. An insulated wire, characterized in that a coating layer made of a resin composition (B) that is 36 to 70% by mass is coated,
(2) The insulated wire according to (1), wherein the metal compound having the hydroxyl group or crystal water contained in the flame retardant resin composition (A) is aluminum hydroxide (3) The insulated wire according to (1) or (2), wherein the resin composition (A) further contains carbon,
(4) The insulated wire according to (1) or (3), wherein the metal compound having the hydroxyl group or crystal water of the resin composition (A) is magnesium hydroxide,
(5) Any one of (1), (3) or (4), wherein the metal compound having the hydroxyl group or crystal water of the resin composition (A) is silane-treated magnesium hydroxide Insulated wire according to item 1,
(6) It is difficult for the resin composition (A) to contain 40 to 160 parts by mass of the metal compound having the hydroxyl group or crystal water and 5 to 65 parts by mass of melamine cyanurate with respect to 100 parts by mass of the resin component (a). The insulated wire according to any one of (1) to (5), which is a flammable resin composition, and
(7) Acrylic rubber is contained in an amount of 5 to 50% by mass in 100% by mass of the resin component (a) of the resin composition (B), and any one of (1) to ( 6 ) Insulated wire according to
Is to provide.

  The insulated wire of the present invention has excellent mechanical properties, heat resistance and the like in addition to the coating resin composition being composed of a non-halogen material. Insulated wires have both excellent flame resistance and high weather resistance that pass strict flame retardant standards, and are also effective as industrial wires and electronic wire harnesses. Is also good.

Hereinafter, the insulated wire excellent in weather resistance having the multilayer coating structure of the present invention will be described in detail.
First, among the flame retardant resin composition (A) and the resin composition (B) that are the inner constituent material and the outer constituent material of the insulated wire having the multilayer coating structure of the present invention, the ethylene-based constituent that constitutes the resin component (a) The components of the copolymer, polyolefin resin, and styrene elastomer and their contents will be described.

(A-1) Ethylene copolymer, acrylic rubber The ethylene copolymer in the present invention includes an ethylene-vinyl acetate copolymer, an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid copolymer, an ethylene- Examples thereof include an ethyl acrylate copolymer, an ethylene-methacrylate copolymer, an ethylene-alkyl acrylate acrylic rubber, and an ethylene-alkyl acrylate-acrylic acrylic rubber. In particular, an ethylene-vinyl acetate copolymer is preferably used in order to improve flame retardancy and weather resistance among ethylene-based copolymers.
In the resin component (a), an ethylene copolymer is essential, and the content thereof is preferably 20 to 100% by mass, more preferably 35 to 90% by mass in 100% by mass of the resin component (a). If the amount is too small, the flame retardancy is lowered, but the weather resistance is markedly lowered.
Furthermore, in the outer resin composition (B), the total amount of vinyl acetate, (meth) acrylic acid ester, (meth) acrylic acid and unsaturated carboxylic acid components in the ethylene copolymer component is the resin component. If it is 36-70 mass%, it was confirmed that a weather resistance and a flame retardance will improve significantly.
In particular, in the outer resin composition (B), by blending 5 to 50% by mass of acrylic rubber in 100% by mass of the resin component (a), while maintaining very high flame retardancy, It becomes possible to have high weather resistance.

(A-2) Polyolefin resin Examples of the polyolefin resin in the present invention include polypropylene resins and ethylene-α-olefin copolymers.
Examples of polypropylene resins that can be used in the present invention include homopolypropylene, ethylene / propylene random copolymers, ethylene / propylene block copolymers, and propylene and other small amounts of α-olefins (for example, 1-butene, 1-butene, Hexene, 4-methyl-1-pentene, etc.), and a copolymer of polypropylene and ethylene-propylene rubber.
The ethylene-α-olefin copolymer is preferably a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms. Specific examples of the α-olefin include propylene, 1-butene, and 1-hexene. 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene and the like. Examples of ethylene-α-olefin copolymers include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), very low density polyethylene (VLDPE), ethylene-propylene copolymer rubber (EPR), and ethylene-butylene copolymer. There are polymerized rubber (EBR), ethylene-α-olefin copolymer synthesized in the presence of a single site catalyst, and the like. Among these, an ethylene-α-olefin copolymer synthesized in the presence of a single site catalyst is preferable.
Examples of the ethylene-α-olefin copolymer synthesized in the presence of the single site catalyst used in the present invention include “AFFINITY” and “ENGAGE” (trade name) from Dow Chemical, and “kernel” (product) from Nippon Polychem. Name) is on the market.
The resin component (a) may or may not contain a polyolefin resin, and its content is 0 to 60% by mass, preferably 0 to 40% by mass, in 100% by mass of the resin component (a).

(A-3) Styrene Elastomer The styrene elastomer in the present invention is a hydrogenated product of a copolymer mainly composed of an aromatic vinyl compound and a conjugated diene compound, and a block structure of the conjugated diene compound and the aromatic vinyl compound. Is a hydrogenated product of a copolymer mainly comprising a random structure or a copolymer mainly comprising a random structure.
The resin component (a) may or may not contain a styrene-based elastomer, and the content thereof is 0 to 30% by mass, preferably 0 to 20% by mass in 100% by mass of the resin component (a).
Examples of the aromatic vinyl compound include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethylstyrene, vinyltoluene, There are p-tert-butylstyrene and the like, and among them, styrene is preferable.
Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and one or more of these are selected. Isoprene and combinations thereof are preferred.

Moreover, what hydrogenated at least 90% of the aliphatic double bond based on a conjugated diene compound is preferable.
The aromatic vinyl compound content is preferably 50% by mass or less, more preferably 45% by mass or less in the elastomer component. If this amount is too large, the flexibility decreases.
The number average molecular weight of the elastomer is preferably about 5,000 to 1,000,000, and the value of polydispersity (Mw / Mn) is preferably 10 or less. Further, the melt flow rate (hereinafter referred to as MFR) (according to ASTM D1238) at 230 ° C. and a load of 21.18 N is preferably 12 g / 10 min or less, more preferably 6 g / 10 min or less.
As such materials, Kuraray sells Septon (trade name) and JSR Corp. sells Dynalon (trade name).

Furthermore, if necessary, a thermoplastic resin can be contained as a resin constituting the resin component (a). For example, mention may be made of a polyolefin resin modified with an unsaturated carboxylic acid.
Examples of the polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof include polyolefin resins such as linear polyethylene, ultra-low density polyethylene, and high density polyethylene.
Examples of the unsaturated carboxylic acid used for modification include maleic acid, itaconic acid, fumaric acid and the like, and examples of the unsaturated carboxylic acid derivative include maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid. Examples include monoesters, itaconic acid diesters, itaconic anhydride, fumaric acid monoesters, fumaric acid diesters, and fumaric anhydride. The modification of the polyolefin can be performed, for example, by heating and kneading the polyolefin and an unsaturated carboxylic acid in the presence of an organic peroxide. The amount of modification with maleic acid is usually about 0.1 to 7% by mass.
By adding a polyolefin resin modified with this unsaturated carboxylic acid or derivative thereof, there is an effect of increasing the elongation of the resulting resin composition and maintaining the strength, and it is possible to keep the volume resistivity high. Those modified with this unsaturated carboxylic acid or derivative thereof also have an effect of alleviating a decrease in mechanical properties due to a metal compound having a hydroxyl group or crystal water and an effect of preventing whitening of an electric wire.

(B) Metal Compound Having Hydroxyl Group or Crystal Water There are no particular limitations on the type of metal compound having a hydroxyl group or crystal water that can be used in the flame retardant resin composition (A) as the inner layer of the present invention. , aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, orthosilicate aluminum, metal compounds having a hydroxyl group or water of crystallization, such as hydrotalcite side elevation Gerare, one alone Two or more kinds may be used in combination.
In the present invention, a part or all of the metal compound is a metal compound that is aluminum hydroxide.
Of these metal compounds having a hydroxyl group or crystal water, aluminum hydroxide is preferred in terms of weather resistance and flame retardancy.
The aluminum hydroxide may include the or untreated those treated with fatty acid. Among them, the untreated one is preferable. In addition, you may use what gave the silane process etc.
Although it does not specifically limit as said magnesium hydroxide, the thing which performed silane treatment is preferable, and what was processed with the silane coupling agent which has an alkyl group, an alkoxy group, an amino group, a vinyl group, a methacryloxy group, an epoxy group, etc. at the terminal Is mentioned. These silane coupling agents may be used alone or in combination of two or more. Among them, it is preferable to use a reactive silane coupling agent such as an amino group, a vinyl group, or an epoxy group at the terminal, and among them, it is preferable to use one having a vinyl group or an epoxy group as one component, for example, Vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxy Examples include propylmethyldimethoxysilane.
By using silane-treated magnesium hydroxide, strength, high flame retardance, and weather resistance can be maintained. Further to with silanized magnesium hydroxide mentioned above may be used in combination with fatty acid treatment or phosphoric acid ester-treated magnesium hydroxide, fatty acid treated with a silane treatment, a phosphate treatment may be I line.
Further , a metal compound having two or more kinds of hydroxyl groups or crystal water such as magnesium hydroxide and aluminum hydroxide may be mixed and used.
By using aluminum hydroxide as a flame retardant for the flame retardant resin composition (A) serving as the inner layer, high flame retardancy and weather resistance can be obtained. High flame retardancy can be obtained by the interaction of the inner layer aluminum hydroxide, melamine cyanurate, the outer layer ethylene copolymer and magnesium hydroxide, and the flame retardant resin composition (A) serving as the inner layer It becomes possible to greatly reduce the amount of the metal compound having a hydroxyl group or crystal water therein . Furthermore, the weather resistance is significantly improved, and an insulated wire that can achieve both weather resistance, heat resistance, flame retardancy, and low temperature can be constructed.

In the resin composition (B) serving as the outer layer of the present invention, magnesium hydroxide is blended in an amount of 150 to 360 parts by mass, preferably 200 to 320 parts by mass with respect to 100 parts by mass of the resin component (a). If the amount is too large, the mechanical properties are insufficient, and if the amount is too small, the viscosity is insufficient.
The magnesium hydroxide used in the resin composition (B) to be the outer layer is preferably at least 1/3 or more, more preferably 1/2 or more treated with a fatty acid and / or a phosphate ester. The treatment amount with respect to magnesium hydroxide is preferably 1.5% by mass or more, more preferably 1.8% by mass or more, and further preferably 2.0% by mass or more.
Examples of the fatty acid include stearic acid, oleic acid, palmitic acid, lauric acid, behenic acid, arachidic acid, and metal salt compounds such as sodium salt and potassium salt.
Examples of the phosphoric acid ester include those represented by the following formula, and examples include stearyl alcohol phosphoric acid ester and its metal salt, lauryl alcohol phosphoric acid ester and its metal salt, and the like.

[In the formula (1), R is an alkyl or alkenyl group having 1 to 24 carbon atoms, A is an alkylene group having 2 to 4 carbon atoms, M is a cation of an alkali metal or an alkylamine having 1 to 4 carbon atoms. Or formula (2)

(In the formula (2), R ′ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, B is an alkylene group having 2 to 4 carbon atoms, and r is an integer of 1 to 3). Represents a cation of an amine, n represents an integer of 0 to 6, and m represents 1 or 2. ]
Further, the treated or treated magnesium hydroxide may be treated with a silane coupling agent or the like. In addition to the above magnesium hydroxide, magnesium hydroxide that has not been treated or treated with a silane coupling agent may be added. However, magnesium hydroxide is preferably treated with at least 1/3 or more, more preferably 1/2 or more with a fatty acid and / or a phosphate ester, and the treatment amount with respect to magnesium hydroxide is 1.5% by mass or more. preferable.
By using magnesium hydroxide treated with a fatty acid and / or a phosphoric acid ester at least 1.5 mass%, the weather resistance is drastically improved. This is particularly noticeable when the amount of magnesium hydroxide is 120 parts by mass or more. Although the cause of this is not clear, defects are generated at the interface between the polymer and the resin due to ultraviolet rays, and radicals are generated, but those that have been sufficiently treated with magnesium hydroxide with a fatty acid or phosphate ester generate these radicals. It is considered that the polymer is less likely to deteriorate.

(C) Melamine cyanurate A melamine cyanurate compound can also be added to the resin composition (A) and the resin composition (B) of the present invention in order to improve flame retardancy.
The melamine cyanurate used in the present invention preferably has a fine particle diameter, and the average particle diameter is preferably 10 μm or less, more preferably 7 μm or less, and further preferably 5 μm or less. Moreover, the melamine cyanurate compound surface-treated from the dispersible surface is used preferably.
Examples of the melamine cyanurate compound that can be used in the present invention include those marketed as MCA-0, MCA-1 (trade name, manufactured by Mitsubishi Chemical Corporation) or MC6000 (trade name, manufactured by Nissan Chemical Industries, Ltd.). is there.
Examples of melamine cyanurate compounds surface-treated with fatty acids and silane surface-treated melamine cyanurate compounds include MC610 and MC640 (both are trade names, manufactured by Nissan Chemical Co., Ltd.).

  Examples of the melamine cyanurate compound that can be used in the present invention include melamine cyanurate having the following structure.

  The melamine cyanurate of the present invention may or may not be contained in the resin composition (A) or the resin composition (B), and its content is 0 to 100 parts by mass of the resin component (a). 90 parts by mass, preferably 5 to 65 parts by mass, more preferably 5 to 40 parts by mass, and still more preferably 8 to 35 parts by mass. When the content is too large, the mechanical strength is lowered and the weather resistance is markedly lowered. By adding this, it becomes possible to make the insulated wire have both higher flame retardancy and weather resistance.

The flame retardant resin composition (A) serving as the inner layer of the present invention preferably further contains carbon.
As carbon used for the flame retardant resin composition (A), furnace carbon and acetylene carbon are preferable. Carbon has a function of absorbing ultraviolet rays and remarkably improves weather resistance. The amount of carbon is preferably 0.6 to 4.0% by mass, preferably 0.8 to 2.8% by mass in the flame retardant resin composition (A).

  In the resin composition constituting the coating layer of the present invention, various commonly used additives such as antioxidants, ultraviolet absorbers, light stabilizers, metal deactivators, lubricants, flame retardants ( Auxiliary) agents, fillers and the like can be appropriately contained within a range not impairing the object of the present invention. Some examples will be described.

The hindered phenol antioxidant used in the present invention is pentaerythrityl-tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), 1,6. -Hexanediol-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate), 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5- Di-t-butylanilino) -1,3,5-triazine, 2,2-thio-diethylenebis (3- (3,5-di-t-butyl-4-hydroxyphenylpropionate), octadecyl-3- ( 3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxy Cibenzyl) benzene and the like.

Usually, the amount of hindered phenol antioxidant used is 0.5 parts by mass or less with respect to 100 parts by mass of the resin component, but in the resin composition of the present invention, at least 1 part by mass in 100 parts by mass of the resin component (a). The amount is preferably 1.3 parts by mass or more, more preferably 1.5 parts by mass or more.
This hindered phenol antioxidant not only retains the heat resistance of the coating resin composition of the present invention, but also functions to trap radicals generated by light degradation. Furthermore, it traps radicals generated by light degradation between the metal compound having a hydroxyl group or crystal water bonded by a silane coupling agent and the polymer and repairs it, thereby suppressing defects between the polymer and the metal hydrate. It is possible to suppress a decrease in elongation and stress cracks of the resin composition after exposure to light such as ultraviolet rays.

Benzophenone and benzotriazole UV absorbers The benzophenone UV absorbers used in the present invention are 2.4 dihydroxybenzophenone, 2hydroxy-4-methoxy-benzophenone, 2hydroxy-4-n-dodecyloxybenzophenone, bis (5 -Benzol-4-hydroxy-2-methoxyphenyl) methane, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone and the like.
Examples of the benzotriazole ultraviolet absorber used in the present invention include 2- (2′-hydroxy-5-methylphenyl) benzophenone, 2- (2′-hydroxy-3 ′, 5′bis (α, α). -Dimethylbenzyl) phenyl) -benzotriazine, 2- (2'hydroxy-3 ', 5'di-t-butyl-5'-methylphenyl) benzotriazine, 2- (2'-hydroxy3', 5'- And di-t monoamyl) benzotriazine, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazine, and the like.

These ultraviolet absorbers are decomposed by the basicity of a metal compound having a hydroxyl group or crystal water and the basicity of a hindered amine light stabilizer. In particular, when a large amount of magnesium hydroxide is used as the metal hydrate, the decomposition becomes severe. By using an ethylene copolymer having an acid content of 20% by mass or more as the resin component as the resin composition, this basicity can be suppressed, and decomposition of the benzophenone or benzotriazole UV absorber can be suppressed. The weather resistance can be greatly improved.

Hindered amine light stabilizer The hindered amine light stabilizer used in the present invention is dimethyl succinate 1- (21-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine heavy. Condensate, poly ((6, (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl) ((2,2,6,6-tetramethyl- 4-piperidyl) imino) hexamethylene ((2,2,6,6-tetramethyl-4-piperidyl) imino)), bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and the like It is done.
This hindered amine light stabilizer has a function of repairing when the bond between a metal compound having a hydroxyl group or crystal water and a polymer via a silane coupling agent is cleaved by light such as ultraviolet rays. In particular, there is a great effect in repairing this bond in the vicinity of the resin surface.
In addition, examples of secondary antioxidants include thioether antioxidants, phosphite antioxidants, and benzimidazole antioxidants.

The coating resin composition of the present invention can be blended with at least one selected from zinc stannate, zinc hydroxystannate and zinc borate as necessary, and can further improve flame retardancy. By using these compounds, the speed of shell formation during combustion is increased and the shell formation becomes stronger. The average particle diameter of zinc borate, zinc hydroxystannate, and zinc stannate used in the present invention is preferably 5 μm or less, and more preferably 3 μm or less.
As zinc borate which can be used in the present invention, specifically, for example, alk Nex _{FRC-500 (2ZnO / 3B 2} 0 3 · 3.5H 2 0), FRC-600 ( trade names, manufactured by Mizusawa Chemical Co. Etc.). Examples of zinc stannate (ZnSnO ₃ ) and zinc hydroxystannate (ZnSn (OH) ₆ ) include Alkanex ZS and Alkanex ZHS (both trade names, manufactured by Mizusawa Chemical Co., Ltd.).

Examples of metal deactivators include N, N′-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1,2,4. -Triazole, 2,2'-oxamidobis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like.
Flame retardant (auxiliary) and filler include carbon, clay, zinc oxide, tin oxide, titanium oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, talc, calcium carbonate, magnesium carbonate, white carbon Etc.
Examples of lubricants include hydrocarbons, fatty acids, fatty acid amides, esters, alcohols, metal soaps, among others, wax E, wax OP (both trade names, manufactured by Hoechst), etc. Ester lubricants that exhibit both lubricity and external lubricity are preferred.

  The resin composition (A) and the resin composition (B) of the present invention are obtained by melt-kneading each of the above components with a commonly used kneading apparatus such as a twin-screw kneading extruder, a Banbury mixer, a kneader, or a roll. be able to.

Next, the insulated wire of the present invention will be described.
The outside of the electric wire (including cable) conductor of the present invention is coated with a crosslinked product of the above-described insulating resin composition of the present invention. The insulating resin composition of the present invention is extrusion-coated around a conductor using an ordinary electric wire manufacturing extruder. In order to bond the silane coupling agent and the polymer, it may be cross-linked thereafter, or a resin compound may be cross-linked at the time of preparing the resin composition with a kneader or a Banbury mixer, and a metal compound having a polymer and a hydroxyl group or crystal water may be used as a silane coupling agent. You may combine through.
The crosslinking method after coating is not particularly limited, and can be performed by an electron beam crosslinking method or a chemical crosslinking method. When the electron beam crosslinking method is used, the electron beam dose is suitably 1 to 30 Mrad, and in order to perform crosslinking efficiently, a methacrylate compound such as trimethylolpropane triacrylate, an allyl compound such as triallyl cyanurate, You may mix | blend polyfunctional compounds, such as a maleimide type compound and a divinyl type compound, as a crosslinking adjuvant.
In the case of the chemical crosslinking method, organic peroxides such as hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxy esters, ketone peroxy esters, and ketone peroxides are blended into the resin composition as a crosslinking agent, and crosslinked by heat treatment after extrusion coating. the intends line.

  The conductor diameter of the insulated wire of the present invention, the material of the conductor, and the like are not particularly limited, and are appropriately determined depending on the application. The thickness of the coating layer of the flame-retardant insulating resin composition formed around the conductor is not particularly limited, but the inner layer is preferably 0.15 to 1 mm and the outer layer is preferably 0.05 to 1 mm. The coating insulating layer is not limited to two layers, and may have a multilayer structure, and may have a lower layer, an intermediate layer, etc. in addition to the coating layer formed of the flame-retardant insulating resin composition of the present invention. . The insulated wire of the present invention can be colored in various colors, and the color is rarely faded.

Next, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.
Examples 1-10 and Comparative Examples 1-5
Content of each component of the resin compositions (A) and resin compositions (B) of Examples 1 to 10 in Table 1 and Comparative Examples 1 to 5 in Table 2 (numbers in the table are in parts by mass unless otherwise noted) Is).
In the table, “content of acid and acid ester component” means the amount of vinyl acetate, (meth) acrylic acid ester, (meth) acrylic acid and unsaturated carboxylic acid in the ethylene copolymer component in resin component (a). This is the total amount of the acid component.
Each component shown in the table was dry blended at room temperature, and melt kneaded using a Banbury mixer to produce each insulating resin composition.

Each component material shown in the table is as follows.
1. Product name: Everflex EV180 Manufacturer: Mitsui DuPont Polychemical Co., Ltd.
Ethylene-vinyl acetate copolymer (a-1)
Vinyl acetate content: 33% by mass
2. Product name: YX-21K Manufacturer: Tosoh Corporation
Ethylene-vinyl acetate copolymer (a-1)
Vinyl acetate content: 41% by mass
3. Product name: Revaprene 800HV Manufacturer: LANXESS
Ethylene-vinyl acetate copolymer (a-1)
Vinyl acetate content: 80% by mass
4). Product Name: Baymac DP Manufacturer: DuPont
Acrylic rubber (a-1)
Ethylene-acrylic methyl copolymer rubber
5. Product name: BC8A Manufacturer: Nippon Polypropylene Co., Ltd.
Block polypropylene (a-2)
MFR: 0.8 g / 10 min6. Product Name: Dynalon 1320P Manufacturer: JSR Corporation
Styrene elastomer (a-3)
6. Hydrogenated styrene-butadiene rubber Product name: Admer XE070 Manufacturer: Mitsui Chemicals, Inc.
Polyethylene modified with maleic anhydride (a-4)
Maleic acid modification amount: 1% by mass
8). Product name: Kisuma 5P Manufacturer: Kyowa Chemical Industry Co., Ltd.
Silane coupling agent treated magnesium hydroxide (b)
Silane coupling agent treatment 0.3%
9. Product name: Kisuma 5J Manufacturer: Kyowa Chemical Industry Co., Ltd.
Phosphate ester-treated magnesium hydroxide (b)
Phosphate treatment 2.3%
10. Product name: Kisuma 5A Manufacturer: Kyowa Chemical Industry Co., Ltd.
Fatty acid-treated magnesium hydroxide (b)
Stearic acid treatment 3%
11. Product name: Kisuma 5AL Manufacturer: Kyowa Chemical Industry Co., Ltd.
Fatty acid-treated magnesium hydroxide (b)
Stearic acid treatment 0.6%
12 Product name: MC6000 Manufacturer: Nissan Chemical Co., Ltd.
Melamine cyanurate (c)

(Other additives)
13. Product Name: Irganox 1010 Manufacturer: Ciba Specialty Chemicals
Hindered phenol anti-aging agent14. Product name: ADK STAB AO-412S Manufacturer: Asahi Denka Kogyo
14. Thioether antiaging agent Product name: TINUBIN111 Manufacturer: Ciba Specialty Chemicals
Hindered amine light stabilizer 16. Product name: ADK STAB A-1413 Manufacturer: Asahi Denka
16. Benzophenone ultraviolet absorber Product name: Asahi Carbon 70 Manufacturer: Asahi Carbon Co., Ltd.
Carbon 18. Calcium stearate Manufacturer: Nippon Oil & Fat Co., Ltd.
Calcium stearate 19. Product name: CR-60 Manufacturer: Dainichi Seika Kogyo
Rutile type titanium oxide20. Heidilite H42M Manufacturer: Showa Denko
Untreated aluminum hydroxide 21. Heidilite H42S Manufacturer: Showa Denko
Aluminum stearate hydroxide

  Next, using an extrusion coating apparatus for producing electric wires, a resin composition (A shown in the table) previously melt-kneaded on a conductor (conducted tin-plated annealed copper stranded wire with a conductor diameter of 1.2 mmφ: 30 / 0.18 mmφ) ) Were coated by an extrusion method to produce each insulated wire. The outer diameter is 2.8 mm (coating thickness 0.8 mm). And the resin composition (B) was further coat | covered on the outer side, and the outer diameter was 3.6 mm (wall thickness of a coating layer 0.4 mm). The crosslinking treatment of the resin compositions (A) and (B) was performed by irradiating the electron beam with 5 Mrad after each coating.

The obtained insulated wire was subjected to the following tests, and the results obtained are shown in Tables 1 and 2.
1) Tensile strength, elongation Create a tubular piece of the coating layer from the elongation (%) of each insulated wire and the insulated wire, and determine the tensile strength (MPa) according to UL1581, distance between marked lines 20 mm, tensile speed It measured on 200 mm / min conditions.
The required properties of tensile strength and elongation are 8 MPa or more and 150% or more, respectively.
2) Weather resistance After the heat treatment at 110 ° C for 20 days using the method of Technical Association No. 130 “Ultraviolet light deterioration promotion test of lighting equipment wires and cables”, the tensile strength of the coating layer of each insulated wire The residual ratio and the elongation (%) (MPa) of the coating layer were measured under the conditions of 20 mm between marked lines and 200 mm / min. A tensile strength residual ratio of 65% or more and an elongation of 50% or more are acceptable.
3) Flame resistance (VW-1)
Each insulated wire was subjected to a vertical flame test of UL1581. Three samples were tested and those that passed all three were “passed” and the others were “failed”.
4) Appearance As for the appearance, the appearance at the time of extrusion coating, the presence / absence of change in the outer diameter of the insulated wire, and the surface condition were visually inspected. Those that could not be extruded were marked with “x”.

In Examples 1 to 10, satisfactory results were obtained for any of the evaluation items. Especially Examples 1-10 have the flame retardance which also passes a severe flame retardance test (VW-1). Therefore, it is also useful as an electronic wire harness.
On the other hand, Comparative Example 1 has poor elongation (heat resistance) after the heat treatment. In Comparative Example 2, even when the surface treatment agent of the metal compound having a hydroxyl group or crystal water of the resin composition (A) was changed, the elongation (weather resistance) was similarly bad. Comparative Example 3 in which the magnesium hydroxide content in the outer layer resin composition (B) does not reach the specified range cannot satisfy the flame retardancy, and the acid or acid ester component in the outer layer resin component In Comparative Example 4 in which the content of C was out of the specified range, the elongation was poor and the flame retardancy could not be satisfied.
Comparative Example 5 in which the magnesium hydroxide content in the resin composition (B) of the outer layer exceeds the specified value is poor in appearance and difficult to extrude, and contains magnesium hydroxide in the resin composition (A) of the inner layer. In Comparative Example 6 in which the amount exceeds the specified value, the elongation is poor.
Thus, it can be seen that in the comparative example, any of the items of elongation, flame retardancy, and appearance cannot be satisfied, and the effect of the present invention cannot be obtained.

Claims (7)

In an insulated wire having a multilayer coating structure, a metal compound having a hydroxyl group or crystal water with respect to 100 parts by mass of an ethylene copolymer and a resin component (a) mainly composed of a polyolefin resin and / or a styrene elastomer, And the outer side of the coating layer which consists of a flame retardant resin composition (A) containing 40-200 mass parts of metal compounds whose aluminum compounds are part or all of aluminum hydroxide and 0-90 mass parts of melamine cyanurate In addition,
150 to 360 parts by weight of magnesium hydroxide and 0 to 90 parts by weight of melamine cyanurate are contained with respect to 100 parts by weight of the resin component (a) mainly composed of an ethylene copolymer and a polyolefin resin and / or a styrene elastomer. In addition, in the resin component (a) in the resin composition, the total amount of vinyl acetate, (meth) acrylic acid ester, (meth) acrylic acid and unsaturated carboxylic acid component of the ethylene copolymer component is the resin component. An insulated wire, wherein a coating layer made of a resin composition (B) of 36 to 70% by mass is coated.   2. The insulated wire according to claim 1, wherein all of the metal compound having the hydroxyl group or crystal water contained in the flame-retardant resin composition (A) is aluminum hydroxide.   The insulated wire according to claim 1 or 2, wherein the resin composition (A) further contains carbon.   The insulated wire according to claim 1 or 3, wherein the metal compound having the hydroxyl group or crystal water of the resin composition (A) is magnesium hydroxide.   5. The insulated wire according to claim 1, wherein the metal compound having the hydroxyl group or crystal water of the resin composition (A) is silane-treated magnesium hydroxide. .   The flame retardant resin in which the resin composition (A) contains 40 to 160 parts by mass of the metal compound having the hydroxyl group or crystal water and 5 to 65 parts by mass of melamine cyanurate with respect to 100 parts by mass of the resin component (a). It is a composition, The insulated wire of any one of Claims 1-5 characterized by the above-mentioned. The insulated wire according to any one of claims 1 to 6 , wherein acrylic resin is contained in an amount of 5 to 50% by mass in 100% by mass of the resin component (a) of the resin composition (B). .