JP3439166B2 - Insulating resin composition and insulated wire - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating resin composition which does not generate a heavy metal compound, a large amount of smoke, or a corrosive gas at the time of disposal such as landfill and incineration, and the inside and outside of an electric / electronic device. Insulated wire used for wiring.

[0002]

2. Description of the Related Art Various properties such as flame retardancy, tensile properties and heat resistance are required for coating materials for insulated electric wires used for internal and external wiring of electric / electronic devices. Therefore, as a coating material for these insulated wires, polyvinyl chloride (PV
It is well known to use a resin composition in which a halogen-based flame retardant containing a bromine atom or a chlorine atom in the molecule is added to a base resin containing C) a compound or an ethylene-based copolymer as a main component. In recent years, various problems have been raised when an insulated electric wire using such a coating material is discarded without proper treatment. For example, when discarded by landfill, problems such as elution of the plasticizer and heavy metal stabilizer compounded in the coating material and generation of a large amount of corrosive gas and generation of dioxin occur when incinerated. For this reason, a technique for coating the electric wire with a non-halogen flame-retardant material that does not generate harmful heavy metals or halogen-based gas has been actively studied. Conventional non-halogen flame retardant materials are
The flame retardant is expressed by blending a halogen-free flame retardant with a resin. Examples of the flame retardant for such a coating material include metal hydrates such as magnesium hydroxide and aluminum hydroxide. However, as a resin,
Polyethylene, ethylene-1-butene copolymer, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-
Propylene-diene terpolymers and the like are used.

[0003]

By the way, an electronic wire harness used in an electronic device is required to have high flame retardancy from the viewpoint of safety.
UL1581 (Reference Standard)
for Electrical Wires, Cab
vertical flammability test (Vertical Fl) specified by LES, and Flexible Cords, etc.
(Ame Test) VW-1 standard and horizontal flame retardant standard, J
It must be capable of clearing the 60-degree tilt flame retardant property specified in IS C3005. Furthermore, regarding properties other than flame retardancy, UL and electrical equipment control standards require high mechanical properties such as a breaking elongation of 100% or more and a breaking tensile strength of 10 MPa or more.

In order to realize such a high degree of flame retardancy and mechanical properties in an insulated wire using a halogen-free flame retardant material, the following techniques have been studied. First, an insulating composition that uses red phosphorus and magnesium hydroxide in combination has been studied. However, due to the coloring of red phosphorus, the electric wire cannot be colored in any color such as white, and red phosphorus can be used when it is discarded. However, there is a problem that there is a risk that water will flow into the ground and enrich the lake. In addition, although an insulating composition containing a large amount of magnesium hydroxide has been studied, it may burn depending on the thickness of the insulating layer, and the flame resistance is insufficient, or the mechanical strength is insufficient. There is a problem of a significant decrease. JP-A-2-75642 discloses an example in which an inorganic flame retardant and a melamine cyanurate compound are used in combination with a polyolefin or an ethylene copolymer. However, the insulated wire using this composition is not compliant with the above VW-1 standard, and the mechanical strength is remarkably lowered when magnesium hydroxide surface-treated with higher fatty acid which is usually used is added up to about 200 parts by weight. To do. Further, in the case of a thin and thin electric wire used as a sensor wire or the like in home electric appliances, it is difficult to adapt the vertical flame resistance, which is a problem.

Further, the insulated wire requires a treatment for peeling off the end of the insulated wire coating layer and connecting it to various metal terminals, and it is required that the coating layer be easily peeled off (hereinafter referred to as peeling property of the wire). To be done. Depending on this possibility, mass production compatibility for home electric appliances and the like is greatly influenced. However, in the case of an insulated wire that uses a normal non-halogen resin composition as a coating material, the peeling property is inferior to that of an insulated wire that uses a conventional PVC resin composition as a coating material, and the coating is performed when the wire is peeled. There is a problem that a part of the layer is extended (hereinafter referred to as whiskers). If the beard or the like remains in the processed portion, there is a high possibility that problems such as poor contact will occur. Further, in the case of a halogen-free flame-retardant composition, there is a problem that a large amount of metal hydrate or the like is mixed, and thus a large amount of eye blemishes occur during extrusion.

The present invention solves these problems and has a high degree of flame retardancy and excellent mechanical properties required for insulated wires,
Insulation that can be colored in any color, the peeling of the coating layer is easy, and there are no problems such as elution of heavy metal compounds and phosphorus compounds by landfill at the time of disposal and generation of a large amount of smoke and corrosive gas due to incineration. It is an object to provide a resin composition and an insulated electric wire using the composition as a coating material.

[0007]

Means for Solving the Problems The inventors of the present invention have made extensive studies in view of the above problems. As a result, an ethylene-acrylic acid alkyl ester copolymer is used as a base resin, and an acrylic rubber and a styrene resin are further used as one component. Using an elastomer, containing a metal hydrate and a divalent metal salt of a fatty acid,
Further, by using a resin composition containing a silicone compound as necessary, V can be applied even in a thin and thin electric wire having severe flame retardancy.
Insulated wire that has excellent flame retardant properties that comply with the W-1 standard, as well as excellent mechanical and electrical properties, has good peeling properties of the coating material from the conductor, and does not generate harmful substances such as dioxin during combustion. It was found that The present invention is based on this finding.

That is, the present invention relates to (1) ethylene-alkyl acrylate copolymer 90 to 30% by weight, acrylic rubber 5 to 50% by weight, styrene elastomer and / or polyolefin having a styrene polymer in a side chain. Metal hydration in which 50% by weight or more is surface-treated with a silane coupling agent to 100 parts by weight of a resin component consisting of 0 to 40% by weight and a polyolefin resin modified with an unsaturated carboxylic acid 0 to 35% by weight. Thing 150
To 280 parts by weight, a divalent metal salt of a fatty acid 3 to 20 parts by weight, and a silicone compound 0 to 15 parts by weight, an insulating resin composition comprising (2) a resin component and ethylene. Binary copolymer acrylic rubber with alkyl acrylate 0-45% by weight, ternary copolymer acrylic rubber with ethylene, alkyl acrylate and unsaturated hydrocarbon having a carboxyl group in the side chain 100-55% by weight % Of the insulating resin composition according to item (1) and the crosslinked body of the insulating resin composition according to item (3) (1) or (2). A characteristic insulated wire is provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, an ethylene-alkyl acrylate copolymer and acrylic rubber, a styrene-based elastomer and / or a polyolefin having a styrene-based polymer in a side chain and, if necessary, an unsaturated carboxylic acid are used. By using a modified polyolefin resin as a base resin, a metal hydrate surface-treated with a silane coupling agent and a predetermined amount of a divalent metal salt of a fatty acid, and if necessary, a predetermined amount of a silicone compound, mechanical properties are improved. An insulating resin composition and an insulated wire having excellent flame retardancy (vertical flame retardancy, etc.) and peeling property are provided. In the insulating resin composition of the present invention, by blending the acrylic rubber, the peeling property is improved without stretching the coating layer in a beard shape during peeling,
Further, it becomes possible to improve flame retardancy.

In the present invention, by using ethylene-acrylic acid alkyl ester and acrylic rubber in combination, not only high flame retardancy can be maintained, but also mechanical strength can be maintained at a high level. Further, by adding a divalent metal salt of a fatty acid to this system, a shell is formed on the surface of the electric wire by thermal crosslinking during combustion, and vertical flame retardancy can be ensured even in an electric wire having a small diameter and a thin wall. Further, by blending at least one selected from the group consisting of a styrene-based elastomer and a polyolefin having a styrene-based polymer in the side chain, the insulation resistance can be significantly improved without lowering the peeling property of the electric wire. This makes it possible to maintain the insulation resistance at a high level without significantly lowering it even when it is submerged or kept under high temperature and high humidity.

Further, as the acrylic rubber, a terpolymer copolymer acrylic rubber of ethylene, an alkyl acrylate and an unsaturated hydrocarbon having a carboxyl group in its side chain is used, whereby a carbonized layer is formed on the surface during combustion. However, the flame retardancy is further increased. Furthermore, by using this ternary acrylic rubber and a divalent metal salt of fatty acid in combination, the rate of shell formation on the surface of the electric wire at the time of combustion becomes very fast, the flame retardancy increases dramatically, and the flame retardant properties are severe. It meets the standard of vertical flame retardancy even for thin and thin electric wires. Further, the shell forming effect at the time of combustion is promoted by the combined use of the silicone compound, and the flame retardancy is also greatly improved. Further, in this case, the flame retardancy is further improved by using the terpolymer acrylic rubber and the ethylene-methyl acrylate copolymer rubber or the ethylene-alkyl acrylate copolymer together. In addition, since the metal hydrate is surface-treated with a silane coupling agent, when the composition is cross-linked, it exhibits extremely high flame retardancy of VW-1 standard conformity level, and further, Even if the amount of hydrate is increased, the required high mechanical strength can be maintained.

Each component used in the insulating resin composition of the present invention will be described below. (A) Ethylene-Acrylic Acid Alkyl Ester Copolymer The insulating resin composition of the present invention uses an ethylene-acrylic acid alkyl ester copolymer as one component of the resin component. Specific examples include ethylene methyl acrylate copolymer, ethylene ethyl acrylate copolymer, ethylene propyl acrylate copolymer, ethylene butyl acrylate copolymer and the like. Among them, ethylene methyl acrylate copolymer and ethylene ethyl acrylate copolymer are preferable from the viewpoint of strength and flame retardancy. Moreover, these ethylene-acrylic acid alkyl esters may be one kind or two or more kinds.

In these ethylene-acrylic acid alkyl ester copolymers, the content of the acrylic acid alkyl ester component is 20% by weight or more, preferably 22%.
It is at least wt%, more preferably at least 24 wt%.
The MFR (melt flow rate) of the ethylene-based copolymer is preferably 0.2 to 20 from the viewpoint of strength and kneadability of the resin composition, and more preferably 0.
It is about 5 to 10. In the present invention, the ethylene-acrylic acid alkyl ester copolymer may be used in combination with other ethylene-based copolymers, but the amount thereof should be 100% by weight or less based on the ethylene-acrylic acid alkyl ester copolymer. I have to. When this ethylene-acrylic acid alkyl ester copolymer is used in combination with acrylic rubber and metal hydrate, high flame retardancy can be maintained. Further, by using it together with a divalent metal salt of fatty acid, it becomes possible to maintain higher flame retardancy.
The amount of the ethylene-alkyl acrylate copolymer should be 90% by weight to 30% by weight in the resin component. If the amount is more than 90% by weight, the cutting characteristics when the electric wire is peeled off and the mechanical characteristics are deteriorated. On the other hand, if the amount is less than 30% by weight, problems such as deterioration of flame retardance and deterioration of insulating properties occur.

(B) Acrylic rubber In the resin composition of the present invention, 5 to 5 of the above resin components are used.
Acrylic rubber can be used within the range of 0% by weight. Acrylic rubber is a rubber elastic body obtained by copolymerizing a small amount of a monomer having various functional groups with an alkyl acrylate such as ethyl acrylate or butyl acrylate as a monomer component. As such, 2-chloroethyl vinyl ether, methyl vinyl ketone, acrylic acid, acrylonitrile, butadiene and the like can be appropriately used. Specifically, Nipol AR (trade name,
Zeon Corporation, JSR AR (trade name, manufactured by JSR) and the like can be used. In particular, it is preferable to use methyl acrylate as the monomer component, and in that case, a binary copolymer with ethylene or an unsaturated hydrocarbon having a carboxyl group in its side chain is used as a monomer. Polymerized terpolymers can be used particularly preferably. Specifically, in the case of a binary copolymer, Baymac D and Baymac DLS, and in the case of a terpolymer, Baymac G, Baymac HG, Baymac LS, and Baymac GLS (trade names, all are Mitsui DuPont Polychemical Co., Ltd.) can be used.

By blending these acrylic rubbers, the peeling property is improved without stretching the covering material in a beard shape when peeling. Further, the flame retardancy is remarkably improved by blending acrylic rubber. By using the acrylic rubber in combination with the ethylene-based copolymer, it is possible to have relatively high insulating properties while maintaining flame retardancy. In particular, when the acrylic rubber and the divalent metal salt of fatty acid are used in combination, thermal cross-linking occurs during combustion and a shell-forming layer is formed on the surface of the resin composition, whereby flame retardancy is significantly improved. This reaction is remarkable especially when ternary acrylic rubber is used alone or in combination, and shows extremely high flame retardancy, and it is possible to clear flame retardancy even in extremely easily flammable thin and thin insulated wires. it can. In the present invention, the acrylic rubber is
It can be used in a proportion of 5 to 50% by weight in the resin component. If the amount of acrylic rubber is less than 5% by weight, problems with flame retardancy and peeling of the wire will occur, and if it exceeds 50% by weight, not only the extrudability of the wire will be significantly deteriorated, but also that of uncrosslinked. This is because the adhesion between the wires is significantly increased and the productivity is significantly reduced.

Further, since the terpolymer copolymer acrylic rubber of ethylene, alkyl acrylate and unsaturated hydrocarbon having a carboxyl group in the side chain is used as the acrylic rubber, the flame retardancy is improved as described above. It is preferable to add. The ternary acrylic rubber is preferably contained in the resin component in an amount of 5% by weight or more, more preferably 7% by weight or more, and further preferably 10% by weight or more. Further, this ternary acrylic rubber tends to increase the extrusion load, which is preferably 50% by weight or less, more preferably 40% by weight or less, and further preferably 35% by weight or less in the resin component. Further, of the acrylic rubber in the resin component, the ternary acrylic rubber is preferably 55 to 100% by weight.
In the present invention, by further using a terpolymer copolymer acrylic rubber of ethylene, an alkyl acrylate and an unsaturated hydrocarbon having a carboxyl group in the side chain, the strength is strengthened and the mechanical strength is improved. Further, since the crosslinked structure becomes denser, it is possible to suppress a decrease in insulation resistance when immersed in water or left under high temperature and high humidity.

(C) Styrenic Elastomer In the present invention, a styrenic elastomer can be used. The styrene-based elastomer is a block copolymer consisting of a polymer block S of styrene and at least one polymer block B containing a conjugated diene compound as a main component, a product obtained by hydrogenating the same, or a mixture thereof. And, for example, S-B-S, B-
Examples thereof include vinyl aromatic compound-conjugated diene compound block copolymers having structures such as S-B-S and S-B-S-B-S, and hydrogenated products thereof. Examples of these conjugated diene compounds include butadiene, isoprene, 1,3-pentadiene,
One type or two or more types are selected from 2,3-dimethyl-1,3-butadiene and the like, and among them, butadiene, isoprene and a combination thereof are preferable. Above (hydrogenation)
Specific examples of the block copolymer include SBS (styrene / butadiene block copolymer), SIS (styrene / isoprene block copolymer), SEBS (hydrogenated SBS), SEPS (hydrogenated SIS) and the like.

(D) Polyolefin having a styrene-based polymer in its side chain (polyolefin grafted with a styrene-based polymer) The polyolefin grafted with a styrene-based polymer is a polyolefin resin, an ethylene-based copolymer, or an ethylene-based copolymer. It is a resin in which polystyrene is grafted to a copolymer of a polymer and an unsaturated carboxylic acid. Examples of the polyolefin resin include linear polyethylene, ultra-low density polyethylene, polyethylene synthesized using a single-site catalyst, polypropylene, etc., and examples of the ethylene-based copolymer include ethylene-vinyl acetate copolymer and ethylene-ethyl acrylate. Examples thereof include copolymers and ethylene-methyl acrylate copolymers. Graft amount of polystyrene is 5
It is about 50% by weight. The product name is MODIPER A
Series (Nippon Yushi Co., Ltd.) and the like.

The styrene-based elastomers (C) to (D) and polyolefins grafted with styrene-based polymers have the function of significantly improving the insulation resistance, and improve the insulation resistance without lowering the peeling property of the electric wire. It is possible to maintain the insulation resistance at a high level without significantly lowering the insulation resistance even when it is submerged or kept under high temperature and high humidity. Among these, the styrene-based elastomer is more preferable from the viewpoints of retaining insulation resistance under water immersion, high temperature and high humidity, and retaining mechanical strength.

(E) Polyolefin modified with unsaturated carboxylic acid The polyolefin modified with unsaturated carboxylic acid means linear polyethylene, ultra-low density polyethylene, high density polyethylene, polypropylene or ethylene-vinyl acetate (V
A) copolymer, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate (EA) copolymer, ethylene-
An ethylenic copolymer such as a methacrylate copolymer is a resin modified with an unsaturated carboxylic acid or a derivative thereof, and examples of the unsaturated carboxylic acid used for modification include maleic acid, itaconic acid, and fumaric acid. Etc.,
As the unsaturated carboxylic acid derivative, maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester,
Fumaric anhydride and the like. The modification of the polyolefin can be carried out, for example, by melting and kneading the polyolefin and the unsaturated carboxylic acid in the presence of the organic peroxide. The modification amount of maleic acid is usually about 0.5 to 7% by weight. Polyolefins modified with unsaturated carboxylic acids have the effect of adhering resins and fillers, ethylene copolymers and styrene elastomers, polyolefins grafted with styrene polymers, and compatibilizers of ethylene propylene rubber. It has the effects of improving the characteristics, suppressing the decrease in insulation resistance when water is immersed, and increasing the strength of the compound. In the present invention, the styrene elastomer and / or the styrene polymer-grafted polyolefin is usually 0 to 40% by weight, preferably 5 to 35% by weight, in the resin component.
The amount of the polyolefin resin modified with unsaturated carboxylic acid is usually 0 to 35% by weight, preferably 5 to 25% by weight.

(F) Metal Hydrate The type of metal hydrate that can be used in the present invention is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, Examples thereof include metal compounds having a hydroxyl group or water of crystallization such as basic magnesium carbonate, aluminum orthosilicate, and hydrotalcide, and may be used alone or in combination of two or more. Among these metal hydrates, aluminum hydroxide and magnesium hydroxide are preferable. Preferably, these metal hydrates are preferably surface-treated with a silane coupling agent. Further, the metal hydrate is preferably magnesium hydroxide. Examples of the silane coupling agent used for the surface treatment of the metal hydrate include those having an alkyl group, an alkoxy group, an amino group, a vinyl group or an epoxy group at the terminal. These silane coupling agents may be used alone or in combination of two or more kinds. Among them, those having a vinyl group or an epoxy group at the terminal are preferably used as one component thereof, for example, vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, Examples thereof include glycidoxypropylmethyldimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, and methacryloxypropylmethyldimethoxysilane. These silane coupling agents having a vinyl group or an epoxy group at the terminal may be used alone or in combination of two or more. The amount of these silane coupling agents is at least 20% by weight, preferably 40% by weight or more, and more preferably 60% by weight or more, based on the total silane coupling agents. In addition, the insulating property can be further improved by using a silane coupling agent having an amino group at the terminal. The content thereof is 60% by weight or less, preferably 40% by weight or less, more preferably 30% by weight or less based on the total silane coupling agent.

As the surface-treated aluminum hydroxide having a silane coupling agent which can be used in the present invention, surface-untreated aluminum hydroxide (such as Hydilite H42M (trade name, manufactured by Showa Denko KK) is used as the above vinyl group or Examples thereof include those surface-treated with a silane coupling agent having an epoxy group at the end. The surface-treated magnesium hydroxide having a silane coupling agent which can be used in the present invention is not surface-treated (as a commercial product, Kisuma 5 (trade name, manufactured by Kyowa Chemical Co., Ltd.)), stearic acid, olein. Those surface-treated with fatty acids such as acids (Kisuma 5A (trade name, manufactured by Kyowa Chemical Co., Ltd.)), those treated with phosphoric acid ester with silane coupling agent, already with silane coupling agent There are commercial products of surface-treated magnesium hydroxide (Kisuma 5LH, Kisuma 5PH (both are trade names, manufactured by Kyowa Chemical Co., Ltd.) and the like). In addition to the above, surface treatment using a silane coupling agent having a vinyl group or an epoxy group at the terminal is additionally performed on magnesium hydroxide or aluminum hydroxide partially surface-treated with a fatty acid or a phosphoric acid ester in advance. The hydrated metal hydrate and the like can also be used.

When the metal hydrate is treated, it can be carried out by blending the untreated or partially surface-treated metal hydrate with a silane coupling agent in advance or at the time of kneading. The silane coupling agent at this time is appropriately added in an amount sufficient for surface treatment, and specifically, it is 0.1 to 3.0% by weight, preferably 0.15 to 2. It is 0% by weight, more preferably 0.2 to 1.0% by weight.
In the present invention, the metal hydrate surface-treated with a silane coupling agent having a vinyl group or an epoxy group at the terminal not only maintains a high mechanical strength as an insulator, but also forms a shell during combustion. Promotes flame retardancy. In the present invention, the amount of the metal hydrate blended is usually 150 parts by weight to 280 parts by weight, preferably 170 to 260 parts by weight, based on 100 parts by weight of the resin component composed of an ethylene copolymer and acrylic rubber. Is. If the content of this metal hydrate is too small, the required flame retardancy cannot be ensured, and if it is too large, the mechanical strength is significantly reduced.

In addition to a metal hydrate surface-treated with a silane coupling agent having a vinyl group or an epoxy group at the terminal, a metal hydrate surface-treated with a material other than the silane coupling agent having a vinyl group or an epoxy group at the terminal. Although a metal hydrate or an untreated metal hydrate can be used, 50% by weight or more, and more preferably 70% by weight or more of the total metal hydrate is a metal hydrate surface-treated with a silane coupling agent. Preferably.

(G) Divalent Metal Salt of Fatty Acid In the present invention, a divalent metal salt of fatty acid is preferably used in order to improve flame retardancy. Examples of such divalent metal salts include zinc salts, magnesium salts, barium salts, calcium salts and the like. Of these, zinc salts and magnesium salts are preferable for improving flame retardancy, and zinc salts are particularly preferable. Examples of the fatty acid of the divalent metal salt of fatty acid include oleic acid, lauric acid, myristic acid, palmitic acid and stearic acid, and stearic acid is preferable. Among them, fatty acid magnesium salt and fatty acid zinc salt are preferably used, more preferably zinc stearate, magnesium stearate, zinc laurate, zinc palmitate, and further preferably zinc stearate. When these divalent metal salts of fatty acids are used in combination with acrylic rubber, ethylene-acrylic acid alkyl ester copolymer and metal hydrate, thermal cross-linking occurs during combustion, and shell formation on the surface of the resin composition hardly occurs. Very flammable. The amount of the divalent metal salt of this fatty acid is usually 3 to 20 with respect to 100 parts by weight of the resin component.
Parts by weight, preferably 3 to 15 parts by weight, more preferably 4 to 12 parts by weight. 20 divalent metal salts of this fatty acid
If it is more than 3 parts by weight, the mechanical strength is remarkably reduced, and if it is less than 3 parts by weight, the effect on flame retardancy is substantially lost. Further, other fatty acid salts and fatty acids may be used in combination with the divalent metal salt of these fatty acids. These fatty acid salts not only promote flame retardancy, but are also effective in preventing the eyes and eyes during extrusion and controlling the adhesion with the conductor.

(H) Silicone Compound When a silicone compound is used in combination, flame retardancy can be further enhanced. By using this silicone compound in combination with acrylic rubber (particularly ternary acrylic rubber) and a divalent metal salt of fatty acid, the shell formation on the surface of the electric wire during combustion becomes extremely large and the flame retardancy is greatly improved. is there.
As the silicone compound, a silicone gum (a polyorganosiloxane having a reactive functional group such as a vinyl group in its side chain, usually having a viscosity at 25 ° C. of 10,000 to several million c).
Liquid material of about St), silicone rubber, silicone oil, polyorganosiloxane (silicone resin) having a trifunctional or tetrafunctional siloxane unit in the molecule,
Examples thereof include silicone-modified organic resins, ladder-type silicone compounds, fine powders of silicone rubber and silicone resins, and inorganic fine powder-supported products of silicone oil. Among them, silicone gum, silicone resin, silicone-modified organic resin, and ladder-type silicone compound are particularly effective in improving flame retardancy. The blending amount of these silicone compounds is 15 parts by weight or less, preferably 0.5 to 8 parts by weight, and more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the resin component. This is because if more than 15 parts by weight is added, the flame retardancy will be decreased and the strength will be significantly decreased. Furthermore, if too much silicone gum, silicone rubber, or silicone oil is added among these silicone compounds, problems will occur in extrusion stability.

Melamine cyanurate may be added to further improve the flame retardancy. The melamine cyanurate compound preferably has a fine particle size. The average particle size of such a melamine cyanurate compound is preferably 10 μm or less, more preferably 7 μm or less, still more preferably 5 μm or less. Further, a melamine cyanurate compound surface-treated from the viewpoint of dispersibility is preferably used. Examples of the melamine cyanurate compound that can be used in the present invention include MCA-0 and MCA-
1 (both are trade names, manufactured by Mitsubishi Chemical) or Chemie Linz
Some are marketed more than Gmbh. As the melamine cyanurate compound surface-treated with fatty acid and the melamine cyanurate compound surface-treated with silane, MC61
0, MC640 (both are trade names, manufactured by Nissan Chemical Co., Ltd.) and the like. Examples of the melamine cyanurate compound that can be used in the present invention include melamine cyanurate having the following structure.

[0028]

[Chemical 1]

In the present invention, the blending amount of the melamine cyanurate compound is preferably 70 parts by weight or less, more preferably 60 parts by weight or less with respect to the total 100 parts by weight of the ethylene copolymer and the acrylic rubber. If the amount of the melamine cyanurate compound is too large, the mechanical strength, especially the elongation is lowered, and the appearance of the electric wire is remarkably deteriorated. The melamine cyanurate compound has the effect of significantly improving flame retardancy due to a synergistic effect with acrylic rubber, and thus may be added when high flame retardancy is required.

The base resin of the insulating resin composition of the present invention is (A) ethylene-acrylic acid alkyl ester copolymer, (B) acrylic rubber, (C) styrene elastomer and / or (D) styrene resin. The above-mentioned polymer is a grafted polyolefin and (E) unsaturated carboxylic acid-modified polyolefin, and other resin components may be added within a range not impairing the object of the present invention.

If necessary, the insulating resin composition of the present invention may be used.
From zinc stannate, zinc hydroxystannate and zinc borate
It is possible to mix at least one selected,
Flame resistance can be improved. With these compounds
Increase the rate of shell formation during combustion,
Becomes stronger. Zinc borate and hydro used in the present invention
Zinc stannate and zinc stannate have an average particle size of 5 μm or less
Is preferable and 3 μm or less is more preferable. For use in the present invention
As a specific example of zinc borate that can be used,
For example, Arcanex FRC-500 (2ZnO / 3B₂ 
O₃ ・ 3.5H₂ O), FRC-600 (both products
Name, manufactured by Mizusawa Chemical Co., Ltd., etc. In addition, zinc stannate (Zn
SnO ₃ ), Zinc hydroxystannate (ZnSn (OH))
₆ ), As Arkanex ZS, Arkanex ZH
S (both are trade names, manufactured by Mizusawa Chemical Co., Ltd.) and the like.

The insulating resin composition of the present invention includes an electric wire / case.
Various additives commonly used in Bull,
For example, an antioxidant, a metal deactivator, a flame retardant (auxiliary) agent, a filler, a lubricant and the like can be appropriately added within a range that does not impair the object of the present invention. 4,4 'as an antioxidant
-Aminic antioxidants such as dioctyl diphenylamine, N, N'-diphenyl-p-phenylenediamine, polymers of 2,2,4-trimethyl-1,2-dihydroquinoline, pentaerythrityl-tetrakis (3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate), octadecyl-3- (3,5-di-
t-Butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl)
Phenolic antioxidants such as benzene, bis (2-methyl-4- (3-n-alkylthiopropionyloxy)
Examples thereof include sulfur antioxidants such as -5-t-butylphenyl) sulfide, 2-mercaptobenzimidazole and zinc salts thereof, and pentaerythritol-tetrakis (3-lauryl-thiopropionate).

As the metal deactivator, N, N'-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1, 2,4-triazole, 2,2'-
Oxamido bis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like can be mentioned. As flame retardant (auxiliary) agent and filler, carbon, clay, zinc oxide, tin oxide, titanium oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, talc, calcium carbonate, magnesium carbonate, white carbon And so on.

Examples of the lubricant include hydrocarbon-based, fatty acid-based, fatty acid amide-based, ester-based, alcohol-based, and metallic soap-based lubricants. Among them, wax E and wax O are preferred.
Examples thereof include ester-based compounds such as P (all trade names, manufactured by Hoechst Co.) and external lubricity, alcohol-based compounds, and metallic soap-based compounds. Furthermore, by using a fatty acid amide together as a lubricant, it becomes possible to easily control the adhesion to the conductor.

The insulating resin composition of the present invention contains the above-mentioned components in the form of a twin-screw kneading extruder, a Banbury mixer, a kneader,
It can be obtained by melt-kneading with a kneading device usually used such as a roll.

Next, the insulated wire of the present invention will be described.
The insulated wire of the present invention is a conductor coated with a cross-linked body of the above-mentioned insulating resin composition of the present invention, and the insulated resin composition of the present invention is used as a conductor using an ordinary extrusion molding machine for electric wire production. It can be produced by extrusion coating the surroundings and then crosslinking the coating layer. By making the coating layer a crosslinked product, not only the heat resistance but also the flame retardancy is improved. The crosslinking method is not particularly limited, and electron beam crosslinking method or chemical crosslinking method can be used. When the electron beam cross-linking method is used, the dose of the electron beam is appropriately 1 to 30 Mrad, and in order to perform cross-linking 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 aid. In the case of the chemical crosslinking method, the resin composition is blended with an organic peroxide such as hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxy ester, ketone peroxy ester or ketone peroxide as a cross-linking agent, and is cross-linked by heat treatment after extrusion molding. Perform. The conductor diameter and the material of the conductor of the insulated wire of the present invention are not particularly limited and may be appropriately determined depending on the application. The thickness of the insulating resin composition coating layer formed around the conductor is not particularly limited, but is preferably 0.15 to 1 mm. Further, the insulating layer may have a multi-layer structure, and may have an intermediate layer or the like in addition to the coating layer formed of the insulating resin composition of the present invention.

[0037]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto. In addition, in the examples, the numeral indicating the composition indicates part by weight unless otherwise specified.

Examples 1 to 16 and Comparative Examples 1 to 7 First, the respective components shown in Tables 1 to 3 were dry blended at room temperature and melt-kneaded using a Banbury mixer to produce respective insulating resin compositions. . Next, an extruding method for extruding the insulating resin composition previously melted and kneaded onto a conductor (tin-plated annealed copper stranded wire having a conductor diameter of 0.78 mmφ: 7 wires / 0.26 mmφ) using an extrusion coating device for electric wire production. Covered by
Each insulated wire was manufactured. The outer diameter was 2.44 mm (the thickness of the coating layer was 0.86 mm), and after coating, electron beam irradiation at 10 Mrad was performed to perform crosslinking. For some materials,
A conductor (conductor diameter 0 ..
78mmφ tinned annealed copper stranded wire Composition: 7 / 0.26
(mmφ) was coated with an insulating resin composition which had been melt-kneaded in advance by an extrusion method to produce insulated wires. The outer diameter was 1.66 mm (wall thickness of the coating layer was 0.42 mm), and after coating, electron beam irradiation at 10 Mrad was performed for crosslinking.

The following compounds were used as the compounds shown in Tables 1 to 3. (01) Ethylene-methyl acrylate copolymer OE5625 (trade name, manufactured by Borealis) MA content 25% by weight (02) Ethylene-ethyl acrylate copolymer A-714 (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.) ) VA content 25% by weight (03) Ethylene-butyl acrylate copolymer OE-6427 (trade name, manufactured by Borealis) BA content 24% by weight (04) Ternary copolymer acrylic rubber Baymac GLS (commodity) (Made by Mitsui DuPont Polychemical Co., Ltd.) (05) Binary copolymer Acrylic rubber Baymac DLS (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.) (06) Styrene elastomer SEPS (hydrogenated styrene-butadiene block copolymer) Septon 2007 (trade name, manufactured by Kuraray Co., Ltd.) (07) Styrene elastomer SEPS (hydrogen Styrene / Butadiene Block Copolymer) Septon 4033 (trade name, manufactured by Kuraray Co., Ltd.) (08) Ethylene-vinyl acetate copolymer modiper A-6100 (trade name, manufactured by NOF CORPORATION) having a styrene polymer in the side chain ( 09) Maleic acid-modified LLDPE (linear low-density polyethylene) L-6100M (trade name, manufactured by JPO) (10) Untreated magnesium hydroxide Kisuma 5 (trade name, manufactured by Kyowa Chemical Co., Ltd.) (11) Vinyl at the end Silane coupling agent having a group Surface-treated magnesium hydroxide Kisuma 5LH (trade name, Kyowa Chemical Co., Ltd.) (12) Untreated aluminum hydroxide Hydilite H42M (trade name, Showa Denko KK) (13) Vinyl group at the end Silane coupling agent TSL8370 (trade name, manufactured by Toshiba Silicone Co.) γ-methacryloxy pro Rutrimethoxysilane (14) Silane coupling agent TSL8350 (trade name, manufactured by Toshiba Silicone) having an epoxy group at the end (15) Silane coupling agent TSL8331 (trade name, manufactured by Toshiba Silicone) having an amino group at the terminal γ -Aminopropyltriethoxysilane (16) Zinc hydroxystannate Alkanex ZHS (trade name, manufactured by Mizusawa Chemical Co., Ltd.) (17) Hindered phenol anti-aging agent Irganox 1010 (trade name, manufactured by Ciba Geigy) (18) 2 Mercaptobenzimidazole zinc salt Nocrac MBZ (trade name, manufactured by Ouchi Shinko Chemical Co., Ltd.) (19) TMPTM (trimethylolpropane trimethacrylate) Ogmont T-200 (trade name, manufactured by Shin Nakamura Chemical Co., Ltd.) (20) Zinc stearate Shinaga Red ZS-101 (Product , Manufactured by Shinagawa Chemical Co., Ltd.), Ltd. (21) silicone gum CF9150 (trade name Toray Silicone Co., Ltd.) (22) silicone modified organic resin SH6018 (trade name Toray Silicone Co., Ltd.)

The following tests were carried out on the obtained insulated wires.
I went. The results are shown in Tables 1 to 3. 1) Elongation, tensile strength Elongation (%) of each insulated wire and tensile strength (MPa) of coating layer
Under conditions of 25 mm between marked lines and 500 mm / min pulling speed
It was measured. The required characteristics of elongation and tensile strength are
100% or more and 10 MPa or more, respectively. 2) Flame retardant For each insulated wire, UL1581 vertical combustion test (V
optical frame test)
The number of passes was shown (number of passes / number of N). 3) Insulation resistance Each insulated wire is specified in JIS C 3005
Insulation resistance is measured and the volume specific resistance is calculated by the following conversion formula.
Was calculated. Volume resistivity is 5 × 10¹³Ω · cm or more
preferable. ρ = (L / 3.665) ・ (1 / (log_Ten(D /
d))) / 10⁷ 4) Peelability Use a flat blade processing machine to peel off the insulated wire coating
The presence or absence of whiskers on the (terminal part) was observed. ○: No beard and good. △: Beard, but very few
Yes. ×: Not cut or large beard 5) Mass production of electric wires Mass production of electric wires can be extruded Electric wire speed, adhesion between wires
It was evaluated by sex. ◯: Good appearance at extrusion speed of 100 m / min or more, and no
Insulators do not stick to each other when bridged. △: Outside at an extrusion speed of 10 m / min or more and less than 100 m / min
It looks good and the insulators stick to each other when not cross-linked.
Is no problem. ×: Extrusion speed, appearance, adhesion between insulators when not cross-linked
There is a problem with either sex.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

[Table 3]

[0044]

INDUSTRIAL APPLICABILITY The insulating resin composition of the present invention is a non-halogen flame-retardant material that does not elute heavy metal compounds or generate a large amount of smoke or corrosive gas at the time of disposal such as landfill, incineration, etc. -It can satisfy extremely high flame retardancy and mechanical strength required for insulated wires of electronic devices. Further, since no phosphorus compound is used, there is no risk of contamination of lakes and marshes due to disposal, and coloring and printing can be performed in any color. Therefore, the insulated wire of the present invention using this has extremely high flame retardancy and mechanical strength, and has high flame retardancy even when used as an electric wire having a small diameter and thin wall. In addition, the insulated wire of the present invention can be freely colored and printed, has a good peeling property from the conductor of the coating portion, is excellent in mass productivity, and
It can be suitably used as an insulated wire for electronic equipment, and has an excellent effect that there are no problems such as elution of heavy metal compounds upon disposal, generation of a large amount of smoke due to incineration, and generation of corrosive gas.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ identification code FI H01B 7/295 H01B 9/00 A 9/00 7/34 B (56) Reference JP-A-9-104797 (JP, A) JP 63-125549 (JP, A) JP 9-169876 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01B 3/00 H01B 7/295 H01B 9/00 C08K 5/09 C08K 9/06 C08L 25/08 C08L 33/06

Claims (3)

(57) [Claims] 1. An ethylene-acrylic acid alkyl ester copolymer 90 to 30% by weight, an acrylic rubber 5 to 50% by weight, a styrene elastomer and / or a polyolefin having a styrene polymer in a side chain, 0 to 40% by weight, Also, 150 to 280 parts by weight of a metal hydrate in which 50% by weight or more is surface-treated with a silane coupling agent based on 100 parts by weight of a resin component consisting of 0 to 35% by weight of a polyolefin resin modified with an unsaturated carboxylic acid. , Divalent metal salt of fatty acid 3 to 20 parts by weight and silicone compound 0
An insulating resin composition, characterized in that the insulating resin composition contains 15 to 15 parts by weight. 2. An unsaturated carbonization in which the acrylic rubber in the resin component is a binary copolymer acrylic rubber of ethylene and alkyl acrylate 0 to 45% by weight, ethylene, an alkyl acrylate and a carboxyl group in the side chain. The insulating resin composition according to claim 1, which comprises 100 to 55% by weight of a ternary copolymer acrylic rubber with hydrogen. 3. An insulated wire, wherein a conductor is coated with a crosslinked body of the insulating resin composition according to claim 1.