JP2021022480A - Wire/cable and method for manufacturing the same - Google Patents

Abstract

To provide a wire/cable excellent in flexibility while maintaining a sufficient tensile strength and a thermal deformation rate.SOLUTION: A wire/cable (1 and 10) is obtained by covering the outer periphery of a conductor (2) with a coating layer (4) consisting of two or more layers including the outermost layer (42) including a flame retardant and an inner layer (41) having one or more layers in the inside of the outermost layer (42). The thickness of the outermost layer (42) is 0.05-0.30 mm; the JIS A hardness of the outermost layer (42) is higher by 7 than that of the inner layer (41); the JIS A hardness of the inner layer (41) is 70-90; and the thickness of the entire coating layer (4) is 1.30-2.50 mm.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electric wire / cable and a method for manufacturing the same.

In recent years, interest in environmental issues has been increasing worldwide, and electric wires and cables using non-halogen compositions that do not generate harmful halogen gas during incineration are becoming widespread. In addition, various proposals have been made for electric wires and cables using non-halogen compositions.

Non-halogen compositions used for electric wires and cables include polyolefin resins.
Therefore, in recent years, non-halogen flame-retardant resin compositions in which a metal hydroxide is blended with a polyolefin resin as a flame retardant have come to be widely used.

For example, Patent Document 1 describes a non-halogen flame-retardant multilayer insulated wire composed of at least two resin layers in which an inner layer is directly or indirectly provided on a metal conductor and an outermost layer is directly provided so as to cover the inner layer. One of the inner layer and the outermost layer has the following composition: (a11) An ethylene-based common weight selected from the group consisting of an ethylene-vinyl acetate copolymer and an ethylene- (meth) acrylic acid ester copolymer. (B1) Metal hydration with respect to a total of 100 parts by mass of the resin component (A1) containing 50 to 80% by mass of the coalescence, 5 to 35 parts by mass of the (a12) polyethylene resin, and 5 to 20% by mass of the (a13) polypropylene resin. It is extruded and coated with a flame-retardant resin composition (X1) having 120 to 300 parts by mass of the product, and the other of the inner layer and the outermost layer has the following composition: (a21) 40 to 95% by mass of polyethylene resin, (a22). ) Contains 0 to 40% by mass of an ethylene-based copolymer selected from the group consisting of an ethylene-vinyl acetate copolymer and an ethylene- (meth) acrylic acid ester copolymer, and (a23) 5 to 30% by mass of a polypropylene resin. A total of 100 parts by mass of the resin component (A2) is extruded and coated with a flame-retardant resin composition (X2) having 120 to 300 parts by mass of (B2) metal hydrate, and the inner layer and the outermost layer are extruded. A non-halogen flame-retardant multilayer insulated wire is disclosed, wherein at least one of the flame-retardant resin compositions constituting the above contains (C) silicone gum in an amount of 1 to 6 parts by mass.

However, conventional electric wires and cables containing a large amount of flame retardant tend to be hard and have a problem that workability is lowered. Therefore, in order to design a composition that imparts flexibility, it is attempted to compound an ethylene-vinyl acetate copolymer having a high vinyl acetate content, a rubber material, etc., but the trade-offs are tensile strength and thermal deformation rate. The problem of worsening arises.

Japanese Unexamined Patent Publication No. 2012-109229

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric wire / cable having excellent flexibility while maintaining a sufficient tensile strength and a thermal deformation rate, and a method for manufacturing the same. There is.

In order to achieve the above-mentioned object, the "electric wire / cable" according to the present invention is characterized by the following (1) to (6).
(1)
In electric wires and cables in which the outer circumference of a conductor is covered with a coating layer
The coating layer is composed of two or more layers having an outermost layer containing a flame retardant and one or more inner layers inside the outermost layer.
The outermost layer has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer is 7 or more higher than the JIS A hardness of the inner layer.
The JIS A hardness of the inner layer shall be 70 to 90, and the overall thickness of the coating layer shall be 1.30 mm to 2.50 mm.
(2)
In the electric wire / cable described in (1) above,
An insulating layer shall be provided between the conductor and the coating layer.
(3)
In the electric wire / cable described in (1) or (2) above,
The outermost layer is composed of a resin composition, and the base resin contained in the resin composition is a polyolefin resin.
(4)
In the electric wire / cable described in (3) above,
The polyolefin-based resin is at least one selected from polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and ethylene-ethyl acrylate copolymer (EEA).
(5)
In the electric wire / cable according to any one of (1) to (4) above.
The inner layer is a foam.
(6)
In the electric wire / cable according to any one of (1) to (5) above,
The outermost layer shall contain a lubricant and / or an antioxidant.

According to the electric wire / cable having the configuration of (1) above, the thickness of the outermost layer, the relationship between the hardness of the outermost layer and the inner layer, the hardness of the inner layer, and the thickness of the coating layer are appropriately set. That is, the thickness of the outermost layer is 0.05 mm to 0.30 mm, the JIS A hardness of the outermost layer is 7 or more higher than the JIS A hardness of the inner layer, and the JIS A hardness of the inner layer is 70 to 90. Moreover, the total thickness of the coating layer is 1.30 mm to 2.50 mm.
By satisfying all of these requirements, it is possible to provide an electric wire / cable having excellent flexibility while maintaining sufficient tensile strength and thermal deformation rate.

According to the electric wire / cable having the configuration of (2) above, since the insulating layer is provided between the conductor and the coating layer, it is possible to provide the electric wire / cable having further excellent mechanical properties.

According to the electric wire / cable having the configuration of (3) above, the outermost layer is composed of a resin composition, and the base resin contained in the resin composition is a polyolefin-based resin. Can be provided.

According to the electric wire / cable having the configuration of (4) above, the polyolefin resin was selected from polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and ethylene-ethyl acrylate copolymer (EEA). Since it is at least one type, it is possible to provide an electric wire / cable having further excellent flexibility and workability.

According to the electric wire / cable having the configuration of (5) above, since the inner layer is a foam, it is possible to provide an electric wire / cable having further excellent flexibility and workability.

According to the electric wire / cable having the configuration of (6) above, since the outermost layer contains a lubricant and / or an antioxidant, it is possible to provide an electric wire / cable having further excellent workability and oxidation resistance.

Further, in order to achieve the above-mentioned object, the "method for manufacturing an electric wire / cable" according to the present invention is characterized by the following (7).
(7)
In a method for manufacturing an electric wire / cable, the outer periphery of a conductor is coated with two or more covering layers having an outermost layer containing a flame retardant and one or more inner layers inside the outermost layer.
A step of extruding a resin composition for forming the inner layer on the outer periphery of the conductor to form the inner layer, and a step of forming the inner layer.
It has a step of extruding a resin composition for forming the outermost layer on the inner layer and forming the outermost layer.
The outermost layer has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer is 7 or more higher than the JIS A hardness of the inner layer.
The JIS A hardness of the inner layer is 70 to 90, and the total thickness of the coating layer is 1.30 mm to 2.50 mm.

According to the method for manufacturing an electric wire / cable having the configuration of (7) above, a step of extruding a resin composition for forming the inner layer on the outer periphery of the conductor to form the inner layer and an outermost layer on the inner layer. It has a step of extruding a resin composition for forming and forming the outermost layer, and includes the thickness of the outermost layer, the relationship between the hardness of the outermost layer and the inner layer, the hardness of the inner layer, and the coating layer. Since the thickness is appropriately set, it is possible to provide an electric wire / cable having excellent flexibility while maintaining sufficient tensile strength and thermal deformation rate.

According to the present invention, it is possible to provide an electric wire / cable having excellent flexibility while maintaining a sufficient tensile strength and a heat deformation rate, and a method for manufacturing the electric wire / cable.

The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through the embodiments for carrying out the invention described below (hereinafter, referred to as "embodiments") with reference to the accompanying drawings. ..

FIG. 1 is a cross-sectional view of an embodiment of an electric wire of the present invention. FIG. 2 is a cross-sectional view of another embodiment of the electric wire of the present invention. FIG. 3 is a cross-sectional view of an embodiment of the cable of the present invention.

Hereinafter, an embodiment of an electric wire / cable according to the present invention will be described with reference to the drawings.

1 to 3 show a cross-sectional view of an electric wire / cable according to this embodiment, FIG. 1 is a cross-sectional view of an electric wire, FIG. 2 is a cross-sectional view of an electric wire of another embodiment, and FIG. 3 is a cross-sectional view of a cable. ..
As shown in FIG. 1, the electric wire 1 in the present embodiment includes a conductor 2 such as a copper wire and a coating layer 4 that covers the outer periphery of the conductor 2. The coating layer 4 is provided on the outermost side of the electric wire 1 and includes an outermost layer 42 containing a flame retardant. In the form shown in FIG. 1, an inner layer 41 is provided inside the outermost layer 42.
Further, as shown in FIG. 2, the electric wire 1 in another embodiment includes a conductor 2 such as a copper wire and a coating layer 4 that covers the outer periphery of the conductor 2. The coating layer 4 is provided on the outermost side of the electric wire 1 and includes an outermost layer 42 containing a flame retardant. In the form shown in FIG. 2, an inner layer 41 is provided inside the outermost layer 42, and the conductor 2 and the inner layer 41 are provided. An insulating layer 3 is provided between the two.
Further, as shown in FIG. 3, the cable 10 according to the present embodiment has a coating layer 4 as a coating layer that covers the bundled plurality of electric wires 1 (1a, 1b) and the peripheral edges of the bundled plurality of electric wires 1. And. The coating layer 4 includes an outermost layer 42 provided on the outermost side of the cable 10. In the form shown in FIG. 3, an inner layer 41 is provided inside the outermost layer 42, and an inner layer 41 is provided between the conductor 2 and the inner layer 41. An insulating layer 3 is provided.

The conductor 2 may be formed by bundling only one wire or by bundling a plurality of wires. As the material of the conductor 2, for example, a conductive metal such as copper, plated copper, copper alloy, aluminum, and aluminum alloy can be used.

The coating layer 4 has an outermost layer 42 provided on the outermost side of the electric wires / cables 1 and 10. Further, in the embodiment shown in FIGS. 1 to 3, the inner layer 41 is provided inside the outermost layer 42. The present invention is not limited to the embodiments shown in FIGS. 1 to 3, and for example, the inner layer 41 may be provided with a plurality of layers.

The outermost layer 42 can be formed of a resin composition containing at least a base resin and a flame retardant.

The base resin can be, for example, a polyolefin resin or a rubber component, and a polyolefin resin is preferable.

The polyolefin-based resin is not particularly limited, but for example, high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), linear low-density polyethylene (L-LDPE), ultra-low-density polyethylene ( Polyethylene (PE) such as V-LDPE), polypropylene (PP), ethylene-propylene copolymer (EPR), ethylene-vinyl acetate copolymer (EVA), ethylene-methylacrylate copolymer (EMA), ethylene- Ethyl acrylate copolymer (EEA) and the like can be mentioned. These polyolefin-based resins may be used alone or in combination of two or more.
Among them, at least one selected from polyethylene (PE), ethylene-vinyl acetate copolymer (EVA) and ethylene-ethyl acrylate copolymer (EEA) from the viewpoint of improving the effect of the present invention. preferable.

Polyolefin resin is preferably a density of ^{0.900~0.970g / cm 3, 0.930~0.960g / cm} 3 is more preferable. By using a polyolefin resin having a density in the above range, the effect of the present invention can be improved and the mechanical properties can be further improved. The melt viscosity (MFR) of the polyolefin resin is preferably 0.3 to 5.0 g / 10 minutes, more preferably 1.0 to 3.0 g / 10 minutes. When the melting temperature of the polyolefin resin is within the above range, the effect of the present invention is improved and the extrusion processability is improved.
The density referred to in the present invention is a value measured in accordance with JIS K7112 (1999), and MFR is measured in accordance with JIS K7210 (2014) at 190 ° C. and a 2.16 kgf load. Value.

Examples of the rubber component include ethylene / propylene / non-conjugated diene copolymer rubber (EPDM) and styrene / ethylene / butylene / styrene copolymer (SEBS). If necessary, the polyolefin resin and the rubber component can be used in combination.

As the flame retardant, a flame retardant that can be used for electric wires / cables can be appropriately selected and used. For example, a brominated ethylene bisphthalimide derivative, a bisbrominated phenylterephthalamide derivative, a brominated bisphenol derivative, and 1, Organic bromine-containing flame retardants such as 2-bis (bromophenyl) ethane; inorganic flame retardants such as metal hydroxides such as magnesium hydroxide and aluminum hydroxide; aromatic condensed phosphates, ammonium polyphosphates, And phosphoric acid-based flame retardants such as melamine phosphate; and intomesent-based flame retardants such as ammonium polyphosphate, melamine polyphosphate, piperazine polyphosphate, ammonium pyrophosphate, melamine pyrophosphate, and piperazine pyrophosphate.
Above all, since metal hydroxide has an adverse effect on the flexibility of electric wires and cables, the effect of the present invention is likely to be exhibited when these flame retardants are used.

The outermost layer 42 may be crosslinked, if necessary.
Examples of the cross-linking agent include, but are not limited to, organic peroxides. Specifically, as the cross-linking agent, dicumyl peroxide (DCP), di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5 -Dimethyl-2,5-di- (tert-butylperoxy) hexin-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3, 3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) ballerate, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxy Examples thereof include isopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butyl cumyl peroxide and the like. These can be used alone or in combination of two or more.

The cross-linking aid is not particularly limited, and examples thereof include compounds having two or more double bonds in the molecule. Specific examples thereof include 1,4-butanediol diacrylate and 1,6-hexanediol diacrylate. , Neopentyl glycol diacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, trimethylolpropylene diacrylate, and diacrylate such as polypropylene glycol diacrylate; 1,3-butanediol dimethacrylate, 1,6 -Dimethacrylates such as hexanediol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and polyethylene glycol dimethacrylate; such as trimethylolpropane triacrylate, tetramethylolmethane triacrylate, and pentaerythritol triacrylate. Triacrylates; trimethacrylates such as trimethylolpropane trimethacrylate and trimethylolethane trimethacrylate; tetraacrylates such as pentaerythritol tetraacrylate and tetramethylolmethane tetraacrylate; divinyl aromatic compounds such as divinylbenzene; triallyl cyanurate, And cyanurates such as triallyl isocyanurate; diallyl compounds such as diallyl phthalate; triallyl compounds and the like. These can be used alone or in combination of two or more.

The amount of the cross-linking agent and the cross-linking aid used can be, for example, 0.03 to 0.10% by mass of the cross-linking agent and 0.03 to 0.10% by mass of the cross-linking aid with respect to the base resin.

In the electric wires / cables 1 and 10 of the present invention, the outermost layer 42 needs to satisfy the following conditions (A) and (B).
(A) The thickness of the outermost layer 42 is 0.05 mm to 0.30 mm.
(B) The JIS A hardness of the outermost layer 42 is 7 or more higher than the JIS A hardness of the inner layer 41.

Under the condition (A), the thickness of the outermost layer 42 is preferably 0.05 to 0.25 mm, more preferably 0.05 to 0.15 mm, from the viewpoint of further improving the effect of the present invention.
Further, under the condition (B), the JIS A hardness of the outermost layer 42 is preferably 7 to 16 higher than the JIS A hardness of the inner layer 41 from the viewpoint of further improving the effect of the present invention, and is 7 to 12 higher. The form is more preferable, and the form which is 7 to 10 higher is further preferable. When a plurality of inner layers are provided, it is preferable that the JIS A hardness is higher than any of the inner layers by the amount in the above range.
The JIS A hardness referred to in the present invention means the shore A hardness measured by a durometer type A based on JIS K6253 (2012).

The inner layer 41 can be formed from the same material as the outermost layer 42. The inner layer 41 can be uncrosslinked and may or may not contain a flame retardant.

In the electric wires / cables 1 and 10 of the present invention, the inner layer 41 needs to satisfy the following condition (C).
(C) The JIS A hardness of the inner layer 41 is 70 to 90. If the above condition (C) is not satisfied, the effect of the present invention cannot be achieved.

Under the condition (C), the JIS A hardness of the inner layer 41 is preferably 70 to 85, more preferably 70 to 80, from the viewpoint of further improving the effect of the present invention. When a plurality of inner layers are provided, it is preferable that the JIS A hardness of any of the inner layers is in the above range.

The JIS A hardness of the outermost layer 42 and the inner layer 41 can be adjusted by selecting a base resin, changing the number of parts of a compounding agent such as a flame retardant, or foaming.

Further, the inner layer 41 can be foamed by a known means to form a foam, and in this form, an electric wire / cable having further excellent flexibility and workability can be provided.

As the foaming agent, a known chemically decomposed foaming agent or the like that generates carbon dioxide gas, nitrogen gas or the like by chemical decomposition can be used. For example, an azo compound such as azodicarbonamide (ADCA), N, N'- Examples thereof include nitroso compounds such as dinitrosopentamethylenetetramine, hydrazine derivatives such as 4,4'-oxybis (benzenesulfonylhydrazide) (OBSH) and hydrazodicarbonamide (HDCA), and sodium hydrogencarbonate.

In the electric wires / cables 1 and 10 of the present invention, the overall thickness of the coating layer 4 needs to satisfy the following condition (D).
(D) The total thickness of the coating layer 4 is 1.30 mm to 2.50 mm.
If the above condition (D) is not satisfied, the effect of the present invention cannot be achieved.

Under the condition (D), the total thickness of the coating layer 4 is preferably 1.30 mm to 2.25 mm, more preferably 1.30 mm to 2.00 mm, from the viewpoint of further improving the effect of the present invention. ..
In the flat cable as shown in FIG. 3, the thickness of the inner layer is not uniform. As described above, when the overall thickness of the coating layer is not uniform, the thickness of the portion where the coating layer is the thinnest is defined as the overall thickness of the coating layer 4.

If necessary, various known additives such as fillers, lubricants, antioxidants, processing aids, ultraviolet absorbers, pigments, antistatic agents, and dispersants can be added to the coating layer 4.

Examples of the filler include light calcium carbonate, heavy calcium carbonate, mica, pentonite, zeolite, slaked lime, kaolin, diatomaceous earth and the like.

Examples of the lubricant include hydrocarbon-based lubricants, fatty acid-based lubricants, ester-based lubricants and the like. In the present invention, a form in which the outermost layer 42 contains a lubricant is preferable.

Examples of the antioxidant include a phenol-based antioxidant, an amine-based antioxidant, and a phosphorus-based antioxidant. In the present invention, it is preferable that the outermost layer 42 contains an antioxidant.

Examples of the processing aid include petroleum oils such as paraffin oils, aromatic oils, and naphthenic oils.

Examples of the ultraviolet absorber include benzophenone compounds, benzotriazole compounds, salicylate compounds, substituted trill compounds, metal chelate compounds and the like.

As the pigment, general inorganic pigments and organic pigments described in "Pigment Handbook (edited by Japan Pigment Technology Association)" can be used. For example, examples of the inorganic pigment include (composite) metal oxides containing titanium such as titanium yellow, zinc oxide, iron oxide, zinc sulfide, antimony trioxide and the like. Examples of organic pigments include phthalocyanine-based, anthraquinone-based, quinacridone-based, azo-based, isoindolinone-based, quinophthalone-based, perinone-based, and perylene-based pigments.

Examples of the antistatic agent include an alkyl phosphate ester and a silicic acid compound.

Examples of the dispersant include acrylic dispersants, fatty acid ester dispersants, polyethylene glycol dispersants, nonionic surfactants, amphipathic triphenylene derivatives, pyrene derivatives and the like.

The insulating layer 3 can be provided as desired, and the material thereof is not particularly limited and can be appropriately selected from known insulators. For example, one made of polyethylene, cross-linked polyethylene, a vinyl mixture or the like is preferably used. Be done. Further, the flame retardant and various additives can be blended as needed.

The electric wires / cables 1 and 10 of the present invention can be manufactured by known means, and have, for example, the following steps.

(1) If necessary, a step of extruding a resin composition for forming the insulating layer 3 on the outer periphery of the conductor 2 to form the insulating layer 3 (2) The outer periphery of the conductor 2 or the insulating layer 3. Step of extruding the resin composition for forming the inner layer and forming the inner layer 41 (3) Step of extruding the resin composition for forming the outermost layer on the inner layer 41 to form the outermost layer 42. At the time of the extrusion, a known extruder such as a single-screw extruder or a twin-screw extruder can be used.

Hereinafter, the present invention will be further described with reference to Examples, but the present invention is not limited to the following examples.

Based on the materials and blending amounts shown in Tables 1 to 3 below, each component was kneaded with a kneader at a temperature of 200 ° C. to prepare a resin composition for the outermost layer 42 and a resin composition for the inner layer 41.

Using an extrusion molding machine, the resin composition for the inner layer 41 and the resin composition for the outermost layer 42 are sequentially extruded onto a copper wire having a diameter of 2.0 mm so as to have the thickness shown in Tables 2 to 3, and various test electric wires are formed. Made.

The following items were measured for the obtained test wire.
JIS A hardness: Shore A hardness was measured with a durometer type A based on JIS K6253 (2012).
Tensile strength: Measured based on JIS C3005 (2014). Pass (◯) is 10 MPa or more.
Tensile elongation: Measured based on JIS C3005 (2014). Pass (○) is 350 mm or more.
Coating layer heating deformation: Measured at a heating temperature of 120 ° C. based on JIS C3005 (2014). Pass (○) is 10% or less.
Coating layer tearing load: Make a 50 mm notch in the coating layer of the test wire cut to a length of 150 cm from the end toward the center (conductor direction), and insert a cutter knife blade into the notch at 150 mm / min. The maximum load when tearing was measured at the speed of. If 10.0 N / mm or less is passed (◯).
Cable flame retardancy: Measured according to JIS C3005 (2014) 4.26. Those that were extinguished within 60 seconds were considered acceptable (good).
Foaming rate: Calculated based on the specific gravity ratio before and after foaming. Specifically, it was calculated by dividing the measured specific gravity after foaming by the measured specific gravity before foaming.

The results are shown in Tables 2-3.

From the results of each of the examples in Tables 1 to 3, the thickness of the outermost layer 42 is 0.05 mm to 0.30 mm, the JIS A hardness of the outermost layer 42 is 7 or more higher than the JIS A hardness of the inner layer 41, and the inner layer. The test wire having a JIS A hardness of 41) of 70 to 90 and an overall thickness of the coating layer 4 of 1.30 mm to 2.50 mm maintains sufficient tensile strength and thermal deformation rate. , Found to have excellent flexibility.

In Comparative Example 1, since the JIS A hardness of the inner layer 41 was less than the lower limit specified in the present invention, the tensile strength and the heat deformation rate deteriorated.
In Comparative Example 2, since the difference in JIS A hardness between the outermost layer 42 and the inner layer 41 was less than 7, the coating layer tearing load was deteriorated.
In Comparative Example 3, since the difference in JIS A hardness between the outermost layer 42 and the inner layer 41 was less than 7, the tensile strength deteriorated.
In Comparative Example 4, since the thickness of the outermost layer 42 was less than the lower limit specified in the present invention, the heating deformation rate deteriorated.
In Comparative Example 5, since the thickness of the outermost layer 42 exceeded the upper limit specified in the present invention, the coating layer tearing load was deteriorated.
In Comparative Examples 6 to 7, since the total thickness of the coating layer 4 was less than the lower limit specified in the present invention, the heating deformation rate or the coating layer tearing load deteriorated.
In Comparative Examples 8 to 9, since the total thickness of the coating layer 4 exceeded the upper limit specified in the present invention, the heating deformation rate or the coating layer tearing load deteriorated.

The present invention is not limited to each of the above embodiments, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, and the like. In addition, the material, shape, size, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

Here, the features of the electric wires / cables according to the present invention and the embodiments of the manufacturing method thereof described above are briefly summarized and listed below (1) to (7), respectively.
(1)
In the electric wire / cable (1, 10) in which the outer circumference of the conductor (2) is covered with the coating layer (4).
The coating layer (4) is composed of two or more layers having an outermost layer (42) containing a flame retardant and one or more inner layers (41) inside the outermost layer (42).
The outermost layer (42) has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer (42) is 7 or more higher than the JIS A hardness of the inner layer (41).
The JIS A hardness of the inner layer (41) is 70 to 90, and the total thickness of the coating layer (4) is 1.30 mm to 2.50 mm. 10).
(2)
In the electric wire / cable of (1) above
An electric wire / cable (1, 10) in which an insulating layer (3) is provided between the conductor (2) and the coating layer (4).
(3)
In the electric wire / cable of (1) or (2) above
The outermost layer (42) is composed of a resin composition, and the base resin contained in the resin composition is a polyolefin resin, which is an electric wire / cable (1, 10).
(4)
In the electric wire / cable of (3) above
Electric wires / cables (1, 10), wherein the polyolefin-based resin is at least one selected from polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and ethylene-ethyl acrylate copolymer (EEA). ..
(5)
In any of the electric wires / cables (1) to (4) above,
The inner layer (41) is an electric wire / cable (1, 10) which is a foam.
(6)
In any of the electric wires / cables (1) to (5) above,
The outermost layer (42) is an electric wire / cable (1, 10) containing a lubricant and / or an antioxidant.
(7)
Two or more coating layers (4) having an outermost layer (42) containing a flame retardant and one or more inner layers (41) inside the outermost layer (42) on the outer circumference of the conductor (2). In the manufacturing method of electric wires / cables (1, 10) covered with
A step of extruding a resin composition for forming the inner layer on the outer periphery of the conductor (2) to form the inner layer (41).
It has a step of extruding a resin composition for forming the outermost layer on the inner layer (41) and forming the outermost layer (42).
The outermost layer (42) has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer (42) is 7 or more higher than the JIS A hardness of the inner layer (41).
The JIS A hardness of the inner layer (41) is 70 to 90, and the overall thickness of the coating layer (4) is 1.30 mm to 2.50 mm. 10) Manufacturing method.

1 Electric wire 2 Conductor 3 Insulation layer 4 Coating layer 41 Inner layer 42 Outer layer 10 Cable

Claims (7)

In electric wires and cables in which the outer circumference of a conductor is covered with a coating layer
The coating layer is composed of two or more layers having an outermost layer containing a flame retardant and one or more inner layers inside the outermost layer.
The outermost layer has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer is 7 or more higher than the JIS A hardness of the inner layer.
An electric wire / cable characterized in that the JIS A hardness of the inner layer is 70 to 90, and the total thickness of the coating layer is 1.30 mm to 2.50 mm. The electric wire / cable according to claim 1, wherein an insulating layer is provided between the conductor and the coating layer. The electric wire / cable according to claim 1 or 2, wherein the outermost layer is composed of a resin composition, and the base resin contained in the resin composition is a polyolefin-based resin. 3. The third aspect of the present invention is that the polyolefin-based resin is at least one selected from polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and ethylene-ethyl acrylate copolymer (EEA). Described electric wires / cables. The electric wire / cable according to any one of claims 1 to 4, wherein the inner layer is a foam. The electric wire / cable according to any one of claims 1 to 5, wherein the outermost layer contains a lubricant and / or an antioxidant. In a method for manufacturing an electric wire / cable, the outer periphery of a conductor is coated with two or more covering layers having an outermost layer containing a flame retardant and one or more inner layers inside the outermost layer.
A step of extruding a resin composition for forming the inner layer on the outer periphery of the conductor to form the inner layer, and a step of forming the inner layer.
It has a step of extruding a resin composition for forming the outermost layer on the inner layer and forming the outermost layer.
The outermost layer has a thickness of 0.05 mm to 0.30 mm.
The JIS A hardness of the outermost layer is 7 or more higher than the JIS A hardness of the inner layer.
A method for manufacturing an electric wire / cable, characterized in that the JIS A hardness of the inner layer is 70 to 90, and the total thickness of the coating layer is 1.30 mm to 2.50 mm.

Images