JP2014159516A - Flame-retardant resin composition, flame-retardant resin molding, insulated wire, and flat cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant resin molding which can be thinned by satisfactorily dispersing a solid phosphorus-based flame retardant in a flame-retardant resin composition, and is excellent in flame retardancy, adhesiveness, flexibility (bendability) and electrical characteristics, and to provide an insulated wire and a flat cable.SOLUTION: A flame-retardant resin composition contains a resin component containing polyethylene and ionomer, and a phosphorus-based flame retardant. The phosphorus-based flame retardant is a solid at the melting point of the polyethylene and the ionomer. The content of the ionomer with respect to the resin component is 3 mass% or more and 30 mass% or less. The content of the phosphorus-based flame retardant with respect to 100 pts.mass of the resin component is 5 pts.mass or more and 35 pts.mass or less.

Description

  The present invention relates to a flame retardant resin composition, a flame retardant resin molded article, an insulated wire, and a flat cable.

  In recent years, electronic devices such as tablet terminals, digital cameras, and personal computers have been downsized. Along with the downsizing of electronic devices, there is a demand for thinning and thinning of insulated wires, flat cables, and the like used inside the housing. In order to meet such requirements, it is necessary to reduce the thickness of the coating layer covering the conductor in an insulated wire or the like.

  Insulated wires have applications that require a diameter of about 200 μm or less. In this case, the thickness of the covering layer of the insulated wire is required to be 100 μm or less. Similarly, the flat cable may be required to have a coating layer thickness of 100 μm or less in order to reduce the thickness. Thus, when reducing the thickness of the coating layer, the resin material for forming the coating layer is required to have high thin-wall processability (extrusion moldability).

  On the other hand, in insulated wires and the like, there are applications that require high flame resistance. As a standard regarding flame retardancy, there is a flame retardancy test (VW-1 test, horizontal combustion test) based on the US UL standard. Become.

  As a technique for improving the flame retardancy of the flat cable, it has been proposed to add a flame retardant to the adhesive layer (see Japanese Patent No. 4662511 and Japanese Patent Application Laid-Open No. 2011-222371). Japanese Patent No. 4662511 discloses a heat-sealable tape for a flat cable having a heat seal layer (adhesive layer) in which a flame retardant and a filler are mixed with a polyester resin. Japanese Patent Application Laid-Open No. 2011-222371 discloses an insulating film for a flat cable having a flame retardant resin layer (adhesive layer) obtained by mixing a copolyester with polyphenylene ether and a phosphorus flame retardant.

  In general, flame retardants can be broadly classified into halogen-based flame retardants such as brominated flame retardants and chlorine-based flame retardants, and non-halogen flame retardants such as phosphorus-based flame retardants, nitrogen-based flame retardants, and hydrated metal compounds. . Halogen-based flame retardants have a tendency to use non-halogen-based flame retardants in recent years because of concern about the generation of harmful gases such as hydrogen halide gas during incineration.

Japanese Patent No. 4662511 JP 2011-222371 A

  However, when a non-halogen flame retardant is used, the amount added is larger than that of the halogen flame retardant in order to satisfy the standards of the US UL standard regarding flame retardancy. Many non-halogen flame retardants cause problems such as a decrease in adhesion between the coating layer and the conductor, a decrease in the flexibility of insulated wires, etc., and a deterioration in electrical characteristics associated with an increase in dielectric constant due to an increase in the amount added. obtain. Therefore, as the non-halogen flame retardant, a phosphorus flame retardant which can be expected to have a high flame retardant improvement effect even if the addition amount is small among non-halogen flame retardants is preferably used.

  However, even if it is a phosphorus-based flame retardant, a solid phosphorus-based flame retardant generally has a high melting point, and it is difficult to disperse well using a general melt-kneading apparatus at a temperature at the time of melt-kneading with a resin material. . As a result, it is difficult for a resin material using a solid phosphorus flame retardant to be thin-walled by resin molding such as extrusion molding. In addition, when a solid phosphorus flame retardant is contained in a coating layer such as an insulated wire, the effect of improving flame retardancy can be expected, but if the phosphorus flame retardant is insufficiently dispersed, the adhesiveness is lowered. Problems such as a decrease in flexibility and deterioration of electrical characteristics cannot be sufficiently improved.

  The present invention has been made based on the circumstances as described above, and enables thin wall processing by satisfactorily dispersing a solid phosphorus-based flame retardant in a flame retardant resin composition. It aims at providing the flame-retardant resin molding which is excellent in adhesiveness, a softness | flexibility (flexibility), and an electrical property, an insulated wire, and a flat cable.

The present invention made to solve the above problems
Contains a resin component containing polyethylene and ionomer and a phosphorus flame retardant,
The phosphorus flame retardant is solid at the melting point of the polyethylene and the ionomer,
The content of the ionomer with respect to the resin component is 3% by mass or more and 30% by mass or less,
It is a flame retardant resin composition whose content with respect to 100 mass parts of said resin components of the said phosphorus flame retardant is 5 mass parts or more and 35 mass parts or less.

Since the flame retardant resin composition contains 3% by mass or more and 30% by mass or less ionomer with respect to the resin component, even if the phosphorus flame retardant is solid at the melting point of the resin component, Dispersibility in the flame retardant resin composition is good. Therefore, if the flame retardant resin composition is used, thin wall processing by resin molding such as extrusion molding becomes possible. Thereby, since the thickness of the flame-retardant resin molded body can be reduced, the thickness of the flame-retardant insulating layer such as an insulated wire or a flat cable can be reduced. As a result, it is possible to contribute to reducing the diameter or thickness of the insulated wire or flat cable.
In addition, since the dispersibility of the phosphorus-based flame retardant is improved by containing an appropriate amount of ionomer, the content of the phosphorus-based flame retardant can be prevented from becoming excessive. Thereby, when using a solid phosphorus flame retardant, the adhesiveness, a softness | flexibility (flexibility), and the fall of an electrical property resulting from the uneven distribution of this phosphorus flame retardant, etc. can be suppressed.
On the other hand, since the flame-retardant resin composition contains an appropriate amount of a phosphorus-based flame retardant in a well-dispersed state, the flame-retardant resin molded body formed using the flame-retardant resin composition It is possible to ensure sufficient flame retardancy.

  As content with respect to the said resin component of the said ionomer, 5 to 20 mass% is preferable. By making the content of the ionomer within the above range with respect to the resin component, the dispersibility of the phosphorus-based flame retardant can be further improved. As a result, the thin-wall processability in the resin molding is further improved, and it is possible to more appropriately meet the demands such as reducing the diameter of the insulated wire, thinning the flat cable, and thinning the flame-retardant resin molding. In addition, in the insulated wire and the flat cable, it is possible to further suppress deterioration in adhesiveness, flexibility (flexibility), and electrical characteristics while ensuring sufficient flame retardancy.

  The content mass ratio between the phosphorus flame retardant and the ionomer is preferably 100/100 or more and 100/40 or less. The dispersibility of the phosphorus flame retardant can be further improved by adjusting the content ratio of the phosphorus flame retardant and the ionomer to the above range. As a result, the thin-wall processability in the resin molding is further improved, and it is possible to more appropriately meet the demands such as reducing the diameter of the insulated wire, thinning the flat cable, and thinning the flame-retardant resin molding. In addition, in the insulated wire and the flat cable, it is possible to further suppress deterioration in adhesiveness, flexibility, and electrical characteristics while ensuring sufficient flame retardancy.

  A zinc ion is preferable as the metal ion of the ionomer. It can be expected that the dispersibility of the phosphorus-based flame retardant is further improved by using zinc as the metal ion of the ionomer. As a result, further improvement in flame retardancy, adhesion, flexibility and electrical properties can be expected.

  As said phosphorus flame retardant, a phosphinic acid metal salt is preferable. By using a phosphinic acid metal salt as a phosphorus-based flame retardant, it is possible to ensure even higher flame retardancy for flame retardant resin molded products, and at the same time, better adhesion, flexibility and electrical properties in insulated wires and flat cables Can be made.

  High density polyethylene is preferable as the polyethylene. By using high-density polyethylene as polyethylene, higher strength is ensured for flame-retardant resin molded products, insulated wires and flat cables formed using the flame-retardant resin composition than when low-density polyethylene is used. can do.

Another aspect of the present invention made to solve the above problems is as follows.
It is a flame retardant resin molded body formed using the flame retardant resin composition.

  Since the flame-retardant resin molded body is formed from the flame-retardant resin composition, it can be formed into a thin wall and has excellent flame retardancy, adhesiveness, flexibility, and electrical characteristics. .

  The flame-retardant resin molded body is preferably formed by extrusion to a thickness of 100 μm or less. The flame retardant resin composition used for the flame retardant resin molded article should be formed by appropriate extrusion molding even if it has an extremely thin wall thickness of 100 μm or less because the phosphorus-based flame retardant is appropriately dispersed. Is possible.

  As the flame retardant resin molded article, a heat recovery article is preferable. This heat recovery article is excellent in flame retardancy and flexibility, and can be formed as a small wall thickness. Moreover, the said heat recovery article can be used for the coating | cover for the connection part of an insulated wire, the coating | cover for the terminal processing of an insulated wire, the coating | cover for bundling a plurality of insulated wires, etc., for example. That is, the heat recovery article can be used for a wire splice, a wire harness, and the like. Therefore, a wire splice, a wire harness, and the like using the heat recovery article can be excellent in flame retardancy, adhesiveness, flexibility, and electrical characteristics. In particular, since the thickness of the heat recovery article can be reduced, it can be suitably used for wire splices, wire harnesses, and the like using extremely fine wires.

  As the flame retardant resin molding, an insulating film is preferable. This insulating film is excellent in flame retardancy, adhesiveness, flexibility, and electrical characteristics, and can be formed as a thin film. Here, the insulating film can be used as, for example, a thermocompression bonding film or a heat shrink film for forming a flat cable. Therefore, the flat cable using the insulating film as the flame-retardant resin molded body is excellent in flame retardancy, adhesiveness, flexibility, and electrical characteristics while meeting demands for downsizing and thinning.

Yet another aspect of the present invention made to solve the above problems is as follows.
An insulated wire comprising a conductor and a flame-retardant insulating layer covering the outside of the conductor,
The flame-retardant insulating layer is the flame-retardant resin molded body.

  Since the insulated wire is formed of the flame retardant resin molded article, it is excellent in flame retardancy, adhesiveness, flexibility, and electrical characteristics. Moreover, since the said insulated wire can make a flame-retardant insulating layer thin, it becomes possible to respond to the request | requirement of diameter reduction.

Yet another aspect of the present invention made to solve the above problems is as follows.
This is a flat cable in which the plurality of insulated wires are aligned.

  Since the said flat cable is provided with the said insulated wire, it becomes the thing excellent in a flame retardance, adhesiveness, a softness | flexibility, and an electrical property. Moreover, since the said insulated wire can reduce the diameter of the said flat cable, it becomes possible to respond to the request | requirement of thickness reduction.

Yet another aspect of the present invention made to solve the above problems is as follows.
A flat cable comprising a plurality of conductors arranged at intervals and a flame-retardant insulating layer covering the outside of these conductors,
A flat cable characterized in that the flame-retardant insulating layer is the flame-retardant resin molding.

  Since the flat cable is formed of the flame-retardant resin molded article, it is excellent in flame retardancy, adhesiveness, flexibility, and electrical characteristics. In addition, since the flat cable can reduce the thickness of the flame-retardant insulating layer, it is possible to meet the demand for reduction in thickness.

  In the flame-retardant resin composition of the present invention, since the solid phosphorus flame retardant is well dispersed, the use of the flame-retardant resin composition enables thin-wall processing by resin molding such as extrusion molding. It is possible to provide a flame-retardant resin molded article excellent in flame retardancy, adhesiveness, flexibility and electrical characteristics, and an insulated wire and a flat cable.

It is a whole perspective view which shows the heat recovery article | item which is an example of the flame-retardant resin molding of this invention. It is sectional drawing which follows the X1-X1 line | wire of FIG. It is a whole perspective view which shows the heat recovery article | item which is an example of the flame-retardant resin molding of this invention. It is sectional drawing which follows the X2-X2 line | wire of FIG. It is a perspective view which shows the edge part of the flat cable which uses the insulating film which is an example of the flame-retardant resin molding of this invention. It is sectional drawing which follows the X3-X3 line | wire of FIG. It is a perspective view equivalent to FIG. 5 which shows the other example of the flat cable using the insulating film which is an example of the flame-retardant resin molding of this invention. It is sectional drawing equivalent to FIG. 6 which shows the further another example of the flat cable using the insulating film of FIG. 5 or FIG. It is a perspective view which shows an example of the insulated wire of this invention. It is sectional drawing which follows the X4-X4 line | wire of FIG. It is a perspective view which shows the coaxial cable which is another example of the insulated wire of this invention. It is sectional drawing which follows the X5-X5 line | wire of FIG. It is a perspective view which shows an example of the flat cable of this invention. It is sectional drawing which follows the X6-X6 line | wire of FIG. It is a perspective view which shows the other example of the flat cable of this invention. It is sectional drawing which follows the X7-X7 line | wire of FIG. It is a typical perspective view for demonstrating the tensile strength test in conductor adhesiveness evaluation.

[Flame-retardant resin composition]
The flame retardant resin composition of the present invention (hereinafter referred to as “flame retardant resin composition (X)”) includes a resin component containing [A] polyethylene and [B] ionomer, [C] phosphorus flame retardant, Contains. The flame retardant resin composition (X) may contain other components as long as the effects of the present invention are not impaired.

<Resin component>
The resin component contains [A] polyethylene and [B] ionomer as described above, but these two components may be main components and may contain other subcomponents.

([A] polyethylene)
[A] Polyethylene is a homopolymer of ethylene, a copolymer of ethylene and 5 mol% or less α-olefin monomer, and 5 mol% or less% having only carbon, oxygen, and hydrogen atoms in the functional group of ethylene and ethylene. It refers to a copolymer with the following non-olefin monomer. [A] The melting point of polyethylene is, for example, 90 ° C. or higher and 200 ° C. or lower.

  [A] The polyethylene includes a low density polyethylene having a density of 0.910 or more and less than 0.930, a medium density polyethylene having a density of 0.930 or more and less than 0.942, and a density of 0.942 or more and 0.960 or less. One high density polyethylene is mentioned. Of these, high density polyethylene is preferred. [A] By using high-density polyethylene as polyethylene, compared to the case of using low-density polyethylene and medium-density polyethylene, a flame-retardant resin molded article formed with the flame-retardant resin composition (X), an insulated wire, and High strength can be secured for flat cables and the like.

  [A] The melt flow rate (MFR) of polyethylene may be set in accordance with the use of the flame retardant resin composition (X), the molding method, and the like, for example, 0.01 g / 10 min or more and 30.0 g / 10 minutes or less. Here, MFR is an index representing the fluidity of the resin. In this embodiment, an extrusion plastometer defined in JIS K6760 is used, and the temperature is 190 ° C. and the load is 2.16 kg in accordance with JIS K7210. It is a measured value.

  [A] When the MFR of polyethylene exceeds 100 g / 10 min, the fluidity is too high, so that it becomes difficult to form a flame-retardant resin molded article, a flame-retardant insulating layer of an insulated wire, or the like into a target shape. There is a fear. In addition, when the [C] phosphorus-based flame retardant is dispersed in the flame-retardant resin composition (X) by melt kneading or the like, the dispersion of the [C] phosphorus-based flame retardant may be insufficient. On the other hand, if the MFR of [A] polyethylene is less than 3.0 g / 10 min, the fluidity is too small, so that molding of a flame-retardant resin molded product, a flame-retardant insulating layer of an insulated wire, etc. may be difficult. is there.

  [A] The content of polyethylene is preferably 70% by mass or more and 97% by mass or less, and more preferably 80% by mass or more and 95% by mass or less with respect to the resin component containing [A] polyethylene and [B] ionomer. When the content of [A] polyethylene is less than 70% by mass, the content of other resin components such as [B] ionomer becomes relatively large, so the MFR of the flame retardant resin composition (X) changes. In addition, the dispersibility of the flame retardant and the resin moldability such as extrusion molding may be deteriorated. On the other hand, when the content of [A] polyethylene exceeds 97% by mass, the content of other resin components such as [B] ionomer becomes relatively small, so that the flame-retardant resin composition (X) is melt-mixed. [C] Phosphorus flame retardant cannot be sufficiently dispersed when prepared by smelting and the like, and as a result, flame retardancy and adhesion of a resin molded body formed using the flame retardant resin composition (X) , Flexibility and electrical properties may be deteriorated.

([B] ionomer)
The [B] ionomer improves the dispersibility of the [C] phosphorus flame retardant in the flame retardant resin composition (X). [B] The ionomer further includes adhesion between the resin molded body formed of the flame retardant resin composition (X) and the adherend to which the resin molded body is adhered, for example, a flame retardant insulating layer. It improves the adhesion between the flame-retardant insulating layer and the conductor in an insulated wire, flat cable or the like formed of the flame-retardant resin composition (X).

  [B] The ionomer is not particularly limited, but [A] an ethylene ionomer is preferable from the viewpoint of compatibility with polyethylene. This ethylene ionomer is obtained by pseudo-crosslinking between molecules of an ethylene copolymer with a metal ion. For example, the melting point is 80 ° C. or higher and 150 ° C. or lower.

  Examples of the ethylene copolymer include an ethylene-methacrylic acid copolymer and an ethylene-acrylic acid copolymer.

  Examples of the metal ion include zinc ion, potassium ion, sodium ion, calcium ion, magnesium ion, lithium ion and the like. Of these metal ions, zinc ions are preferred. By using zinc ions as metal ions, it can be expected that the dispersibility of the [C] phosphorus-based flame retardant in the flame retardant resin composition (X) will be further improved. As a result, flame retardancy, adhesion, bending And further improvement in electrical properties can be expected.

  [B] The MFR of the ionomer may be selected from a range in which the dispersibility of the [C] phosphorus-based flame retardant in the flame retardant resin composition (X) can be appropriately improved. [A] MFR of polyethylene used It is preferable to select based on the amount of comonomer component and the like. [B] The MFR of the ionomer is preferably 0.01 g / 10 min or more and 5.0 g / 10 min or less. [B] The MFR of the ionomer is a value measured by the same method as [A] polyethylene.

  [B] The content of the ionomer is preferably 3% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less with respect to the resin component. When the content of [B] ionomer is less than 3% by mass, the effect of adding [B] ionomer, for example, the effect of improving the dispersibility of [C] phosphorus flame retardant cannot be obtained sufficiently. As a result, it is not possible to sufficiently ensure the flame retardancy, adhesiveness, flexibility, and electrical characteristics of a resin molded body formed using the flame retardant resin composition (X). On the other hand, when the content of [B] ionomer exceeds 30% by mass, the MFR of the flame retardant resin composition (X) becomes small and the resin moldability deteriorates.

  The mass ratio of [C] phosphorus flame retardant and [B] ionomer is preferably 100/100 or more and 100/40 or less. By making the content mass ratio within the above range, the effect of improving the dispersibility of [C] phosphorus flame retardant by containing [B] ionomer can be sufficiently obtained, and [C] phosphorus flame retardant is contained. The effect of improving flame retardance can be sufficiently obtained.

(Subcomponent)
As the resin component, in order to improve the chemical resistance, workability, impact resistance, cost reduction, etc. within the range in which the flame retardant resin composition (X) can achieve the target characteristics in the present invention, [ A resin other than A] polyethylene and [B] ionomer may be included as an auxiliary component. As content of a subcomponent, 30 mass parts or less are preferable, and 15 mass parts or less are more preferable.

  Examples of the auxiliary component include polypropylene, acrylic acid grafted polyethylene, maleic anhydride grafted polyethylene, acrylic acid grafted polypropylene, polyethylene copolymer (ethylene-vinyl acetate copolymer, ethylene-ethylene acrylate copolymer, ethylene-methyl acrylate copolymer). Polymer, ethylene-butyl acrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene- (meth) acrylic polymer acid copolymer , Ethylene-acrylic acid copolymer, ethylene-vinyl alcohol copolymer, etc.), styrene elastomer (styrene-ethylenebutene-styrene copolymer, styrene-ethylene-ethylenepropylene-styrene) Polymer), polyamide (6 nylon, 11 nylon, etc.), polyester (polybutylene terephthalate, polyethylene terephthalate, etc.), engineering plastic (polycarbonate, modified polyphenylene ether, etc.), thermoplastic elastomer, biodegradable polymer, plant-derived polymer, etc. Is mentioned.

<[C] Phosphorus flame retardant>
[C] A phosphorus-based flame retardant is a flame retardant resin molded body formed using the flame retardant resin composition (X), an insulated wire or a flat cable having the flame retardant resin molded body as a flame retardant insulating layer. Etc. to improve flame retardancy. This [C] phosphorus flame retardant is solid at the melting point of [A] polyethylene and [B] ionomer, for example, 80 ° C. or more and 200 ° C. or less. [C] The melting point of the phosphorus-based flame retardant is preferably 250 ° C. or higher and 500 ° C. or lower.

  [C] The phosphorus-based flame retardant is not particularly limited. For example, polyphosphoric acid obtained by ring-opening polymerization of a phosphinic acid metal salt, a melamine phosphate compound, an ammonium phosphate compound, a cyclic organophosphorus flame retardant, and cyclophosphazene. Examples thereof include phosphazene compounds. Among these organophosphorus flame retardants, phosphinic acid metal salts are preferable because of their excellent flame retardancy.

  Examples of the phosphinic acid metal salt include compounds represented by the following formula (1).

In the following formula (1), R ¹ and R ² are each independently an alkyl group having 1 to 8 carbon atoms or an aryl group having 12 or less carbon atoms. M is an alkali metal such as calcium, aluminum, zinc, magnesium, potassium, sodium, lithium, ammonium, barium, strontium, an alkaline earth metal, a trivalent metal, a monovalent to trivalent transition metal, or ammonium. . Among these, R ¹ and R ² are preferably an organic phosphinic acid metal salt which is an alkyl group having 1 to 8 carbon atoms or an aryl group having 12 or less carbon atoms, and the metal is preferably calcium, aluminum or zinc. More preferably, it is aluminum.

  Examples of the hypophosphorous acid metal salt include organic phosphinic acid aluminum salts. As the organic phosphinic acid aluminum salt, for example, “Exolit OP1230”, “Exolit OP1240”, “Exolit OP930”, “Exolit OP935” (all manufactured by Clariant) and the like can be used.

  Examples of the melamine phosphate compound include melamine polyphosphate, melamine polyphosphate, melamine phosphate, melamine orthophosphate, and melamine pyrophosphate. As the melamine polyphosphate, “MELAPUR200” (manufactured by BASF Japan Ltd.) or the like can be used.

  Examples of the ammonium phosphate compound include ammonium polyphosphate, polyphosphate amide, ammonium polyphosphate amide, and polyphosphate carbamic acid.

  Examples of the cyclic organophosphorus flame retardant include compounds represented by the following formula (2), (3) or (4).

  Polyphosphazene compounds obtained by ring-opening polymerization of cyclophosphazene include “SPR-100”, “SA-100”, “SR-100”, “SRS-100”, “SPB-100L” (all Otsuka Chemical). Etc.) can be used.

  [C] As the phosphorus-based flame retardant, one having a surface treated with a surface treatment agent such as melamine, melamine cyanurate, fatty acid, silane coupling agent, or the like may be used. In this case, the [C] phosphorus-based flame retardant may be subjected to surface treatment in advance before preparing the flame retardant resin composition (X), and also prepare the flame retardant resin composition (X). Sometimes, a surface treatment agent may be added to treat the surface during preparation of the flame retardant resin composition (X).

  The exemplified [C] phosphorus-based flame retardants may be used alone or in combination. When the exemplified [C] phosphorus-based flame retardant is used alone, aluminum hypophosphite, melamine-polyaluminum phosphate, aluminum tripolyphosphate and the like are preferable. Examples of the combination of the exemplified [C] phosphorus-based flame retardant include a combination of an organic phosphinic acid aluminum salt as a phosphinic acid metal salt and a polyphosphoric acid melamine as a melamine phosphate compound. As the [C] phosphorus-based flame retardant in such a combination, for example, “EXOLITOP1321” (manufactured by Clariant) can be used.

  [C] The content of the phosphorus-based flame retardant is preferably 5 parts by mass or more and 35 parts by mass or less with respect to 100 parts by mass of the resin component. When the content of the [C] phosphorus flame retardant is less than 5 parts by mass, the effect of improving the flame retardancy due to the inclusion of the [C] phosphorus flame retardant cannot be sufficiently obtained. On the other hand, when the content of the [C] phosphorus-based flame retardant exceeds 35 parts by mass, it is difficult to sufficiently disperse the [C] phosphorus-based flame retardant, and formed using the flame retardant resin composition (X). It becomes difficult to ensure sufficient flame retardancy, adhesiveness, flexibility and electrical properties of the resin molded product.

  [C] In addition to the phosphorus-based flame retardant, a phosphate ester may be used in combination in order to further improve the flame retardancy. Examples of phosphoric acid esters include trimethyl phosphate, triethyl phosphate, triphenyl phosphate, tricresidyl phosphate, trixylenyl phosphate, cresyl phenyl phosphate, cresyl 2,6-xylenyl phosphate, 2- Ethylhexyl diphenyl phosphate, 1,3 phenylene bis (diphenyl phosphate), 1,3 phenylene bis (di 2,6 xylenyl phosphate), bisphenol A bis (diphenyl phosphate), resorcinol bisdiphenyl phosphate, octyl diphenyl Phosphate, diethylene ethyl ester phosphate, dihydroxypropylene butyl ester phosphate, ethylene disodium ester phosphate, t-butyl phosphate Nildiphenyl phosphate, bis- (t-butylphenyl) phenyl phosphate, tris- (t-butylphenyl) phosphate, isopropylphenyldiphenyl phosphate, bis- (isopropylphenyl) diphenyl phosphate, tris- (isopropylphenyl) phosphate, tris (2 -Ethylhexyl) phosphate, tris (butoxyethyl) phosphate, trisisobutyl phosphate, methylphosphonic acid, dimethyl methylphosphonate, diethyl methylphosphonate, ethylphosphonic acid, propylphosphonic acid, butylphosphonic acid, 2-methyl-propylphosphonic acid, t-butyl Phosphonic acid, 2,3-dimethylbutylphosphonic acid, octylphosphonic acid, phenylphosphonic acid, diethylphosphinic acid, methylethyl Sufin acid, methyl propyl phosphinic acid, diethyl phosphinic acid, dioctyl phosphinic acid, phenyl phosphinic acid, diethyl phenyl phosphinic acid, diphenyl phosphinic acid, alkyl phosphoric acid ester and the like.

  As content of phosphate ester, 1 to 20 mass parts is preferable with respect to 100 mass parts of [C] phosphorus flame retardant. When the content of the phosphate ester is less than 1 part by mass, the effect of improving flame retardancy cannot be sufficiently exhibited. On the other hand, when the content of the phosphate ester is larger than 20 parts by mass, the effect of improving the adhesiveness, flexibility (flexibility), electrical properties, and the like by the [C] phosphorus-based flame retardant may be hindered.

  Flame retardant adhesive composition (X) is [A] polyethylene, [B] ionomer and [C] phosphorus flame retardant, if necessary, other resin components or additives, open roll, pressure It can produce by mixing with mixers, such as a kneader, a single screw mixer, and a twin screw mixer.

  When preparing the flame retardant resin composition (X), the [B] ionomer does not necessarily need to be added in a state in which the molecules of the polymer such as the ethylene copolymer are pre-crosslinked with metal ions in advance. A metal compound may be added, and the polymer molecules may be pseudo-crosslinked with metal ions when preparing the flame retardant resin composition (X).

  For example, at the time of preparing the flame retardant resin composition (X), by adding a polymer such as an ethylene copolymer having a carboxyl group and a metal compound such as a metal oxide, a metal hydroxide, and a metal salt, A composition containing a pseudo-crosslinked ethylene-based ionomer can be obtained. Specifically, when an ethylene copolymer having a carboxyl group and a metal compound are added, the carboxyl group of the polymer is neutralized by a metal ion to become a carboxylate ion to form a salt of the metal ion. By neutralizing a plurality of carboxylate ions with metal ions, the ethylene copolymers are pseudo-crosslinked, and [B] ionomer is generated in the flame retardant resin composition (X).

  Examples of the ethylene copolymer having a carboxyl group in the molecule include a copolymer of an acrylic monomer having a carboxyl group such as acrylic acid and methacrylic acid and ethylene, and a copolymer of an acid anhydride monomer such as maleic anhydride and ethylene. A polymer etc. are mentioned. These copolymers can be produced by known methods such as a copolymerization method and a graft polymerization method, and other monomers can be appropriately copolymerized for the purpose of improving various properties. .

  As content of the carboxyl group of the ethylene copolymer which has a carboxyl group in a molecule | numerator, 0.5 mol% or more and 50 mol% or less are preferable, and 1 mol% or more and 30 mol% or less are more preferable. When the carboxyl group content is less than 0.5 mol%, the flame retardancy resin composition (X) extrusion processability and the rigidity of the flame retardant resin molded product are lowered. On the other hand, when the content of the carboxyl group exceeds 50 mol%, the electrolytic solution resistance decreases. Examples of such an ethylene copolymer include an ethylene-acrylic acid copolymer and an ethylene-methacrylic acid copolymer having an acrylic acid copolymerization ratio of 5% or more and 30% or less. Trade names such as “Registered Trademark” ”(Mitsui DuPont Polychemical Co., Ltd.) and“ Primacol® ”(Dow Chemical Co., Ltd.) can be used.

  Examples of the metal compound such as metal oxide, metal hydroxide or metal salt include zinc oxide, magnesium oxide, magnesium hydroxide, sodium hydroxide, sodium hydrogen carbonate, calcium oxide, calcium hydroxide, calcium carbonate, potassium hydroxide. And potassium hydrogen carbonate. The mixing amount of the metal compound is preferably 1% by mass or more and 10% by mass or less with respect to 100 parts by mass of the ethylene copolymer having a carboxyl group.

  Examples of additives for the flame-retardant resin composition (X) include antioxidants (hindered phenol-based antioxidants, hindered amine-based stabilizers, etc.), [C] surface treatment agents for phosphorus-based flame retardant flame retardants (melamine) , Melamine cyanurate, fatty acids, silane coupling agents, etc.), flame retardant aids (various metal compounds, metal nitrates, organometallic complexes, etc.), anti-aging agents, colorants, lubricants, processing stabilizers, heat stabilizers And ultraviolet absorbers.

  Next, the flame-retardant resin molded product of the present invention will be described with reference to the drawings.

[Flame-retardant resin molding]
Examples of the flame retardant resin molded body include the heat recovery article shown in FIGS. 1 to 4 and the insulating film shown in FIGS. 5 to 8 as examples applied to a flat cable.

<Heat recovery article>
The heat recovery article Y1 of FIGS. 1 and 2 is used, for example, for covering a connection portion between insulated wires, covering for binding the insulated wires, or the like. That is, the heat recovery article Y1 can be applied to a wire splice, a wire harness, or the like. This heat recovery article Y1 is formed in a tube shape having both ends opened, and is reduced in diameter when heated.

  The heat recovery article Y1 can be formed, for example, through processes such as an extrusion molding process, a shape fixing process, and a crosslinking process as necessary.

  The extrusion molding process is carried out using a flame-retardant resin composition (X) as a material and a melt extrusion molding machine. In this extrusion molding treatment, since the flame-retardant resin composition (X) in which the [C] phosphorus-based flame retardant is appropriately dispersed is used, extrusion molding can be appropriately performed. As a result, when the heat recovery article Y1 is formed to be thin, for example, even when it is formed to be 0.1 mm (100 μm) or less, extrusion molding can be appropriately performed.

  The shape fixing treatment is performed by expanding the diameter of the extruded molded product in a state where the extruded molded product is heated to a temperature equal to or higher than the melting point, and then cooling and fixing the shape. The diameter of the extruded product is increased, for example, by introducing compressed air into the extruded product.

  The crosslinking treatment is performed for the purpose of improving the heat resistance of the heat recovery article Y1. This crosslinking treatment is performed before the shape fixing treatment is performed on the extruded product. Examples of the crosslinking method include methods such as crosslinking by irradiation with ionizing radiation, chemical crosslinking, and thermal crosslinking.

  The dimensions of the heat recovery article Y1 can be set according to the application, etc. For example, in the state of the extruded product before fixing the shape, the inner diameter D1 is 1.0 mm or more and 30 mm or less, and the wall thickness T1 is 0.05 mm or more. 10 mm or less, and length dimension L1 shall be 1.0 cm or more and 50 cm or less. The dimensions of the heat recovery article Y1 (extruded product) shown here are merely examples, and do not define the heat recovery article of the present invention.

  The heat recovery article Y2 shown in FIGS. 3 and 4 is used for terminal processing of wiring using an insulated wire, a cable, or the like. The heat recovery article Y2 is formed in a cap shape having one end opened and the other end closed. The heat recovery article Y2 is formed by, for example, heat-shrinking the other end of the heat recovery article Y1 in FIGS. 1 and 2 and closing the other end. That is, the dimensions D2, T2, and L2 of each part of the heat recovery article Y2 are set to be approximately the same as the dimensions D1, T1, and L1 of each part of the heat recovery article Y1.

  Here, as described above, the flame retardant adhesive composition (X) used for forming the heat recovery articles Y1 and Y2 is a material in which the [C] phosphorus flame retardant is well dispersed. Therefore, the heat recovery articles Y1 and Y2 are excellent in flame retardancy, flexibility and electrical characteristics. In addition, since the flame retardant adhesive composition (X) contains an appropriate amount of [B] ionomer, sufficient adhesiveness is ensured with the insulated wires to which the heat recovery articles Y1 and Y2 are attached. can do. Such an effect can be appropriately obtained even when the thicknesses T1 and T2 of the heat recovery articles Y1 and Y2 are reduced to 0.10 mm (100 μm) or less.

<Insulating film>
The insulating film Y3 of FIGS. 5 and 6 is used to fix a plurality of (six in this embodiment) insulated wires 31 in the flat cable 30 in a state where they are aligned. It is formed in a sheet shape.

  The insulated wire 31 is obtained by coating a conductor 32 with an insulating layer 33. As the conductor 32, either a single wire (elementary wire) or a stranded wire obtained by twisting a plurality of strands may be used. In the flat cable 30, instead of the insulated wire 31, a coaxial cable or the like in which the insulated wire 31 is covered with a protective layer can be used. The coaxial cable in this case may be either a single-core cable in which one insulated wire is covered with a protective layer or a multi-core cable in which a plurality of insulated wires are covered with a protective layer.

  The flat cable 30 can be formed by attaching a connector 34 to the end after fixing a plurality of insulated wires 31.

  The plurality of insulated wires 31 are fixed by sandwiching the insulated wires 31 with a pair of insulating films Y3 in a state where the plurality of insulated wires 31 are aligned in the radial direction. At this time, the ends of the pair of insulating films Y3 are joined to each other with the adjacent insulated wires 31 in contact with each other. The joining of the end portions of the pair of insulating films Y3 can be performed by, for example, thermocompression bonding. The thermocompression may be selectively performed only on the end portion of the insulating film Y3, or the entire insulating film Y3 may be thermocompression bonded.

  The insulating film Y4 in FIG. 7 is used to fix a plurality of (six in this embodiment) insulated wires 41 in the flat cable 40 in a state where they are aligned, and is formed in a strip shape. Has been. The plurality of insulated wires 41 in the flat cable 40 are fixed at a plurality of locations (two locations in the present embodiment) using a plurality of pairs (two pairs in the present embodiment) of the insulating films Y4. The insulating films Y4 can be joined to each other by thermocompression bonding similarly to the insulating film Y3 (see FIGS. 5 and 6) of the flat cable 30.

  The flat cable 50 in FIG. 8 is a cable in which a plurality of insulated wires 51 are fixed with an insulating film Y5 in a state where they are arranged through a gap so that adjacent ones do not contact each other. In this flat cable 50, since there is a gap between the insulated wires 51, the insulating film Y <b> 5 has a form that follows the surface shape of the insulated wires 51.

  The insulating films Y3 to Y5 are formed using the flame retardant adhesive composition (X) so that the thicknesses T3, T4, and T5 are 0.05 mm or more and 5 mm or less by, for example, extrusion molding.

  Here, as described above, the flame retardant adhesive composition (X) used for forming the insulating films Y3 to Y5 is one in which the [C] phosphorus flame retardant is well dispersed. Therefore, extrusion molding can be appropriately performed when forming the insulating films Y3 to Y5. As a result, when the insulating films Y3 to Y5 are formed thin, for example, even when the insulating films Y3 to Y5 are formed to have a thickness of 0.1 mm (100 μm) or less, extrusion can be appropriately performed. Thereby, in flat cable 30,40,50, it becomes possible to suppress the thickness increase resulting from insulating film Y3-Y5.

  Insulating films Y3 to Y5 contain [C] phosphorus-based flame retardant in which flame-retardant adhesive composition (X) is well dispersed and an appropriate amount of [B] ionomer. Excellent flexibility and electrical properties. In addition, since the flame retardant adhesive composition (X) contains an appropriate amount of [B] ionomer, sufficient adhesion between the insulating films Y3 to Y5 and the insulated wires 31, 41, 51 can be obtained. Can be secured. Such an effect can be appropriately obtained even when the thicknesses T3, T4, and T5 of the insulating films Y3 to Y5 are reduced to 0.10 mm (100 μm) or less.

  Next, the insulated wire and flat cable of this invention are demonstrated, referring FIG. 9 thru | or FIG. 9 and 10 show examples of insulated wires, Figs. 11 and 12 show other examples of insulated wires, Figs. 13 and 14 show examples of flat cables, and Figs. 15 and 16 show flat cables. Other examples are shown.

<Insulated wire>
The insulated wire Z1 of FIGS. 9 and 10 is obtained by coating the outer peripheral side of the conductor 60 with a flame-retardant insulating layer 61.

  The conductor 60 is a stranded wire in which a plurality (seven in this embodiment) of strands 62 are twisted together. The diameter D6a of the conductor 60 is, for example, AWG 26 or more and 44 or less (0.063 mm or more and 0.48 mm or less) in the standard of AWG (American Wire Gauge).

  As the strand 62, for example, a tin-plated annealed copper wire having a diameter D6b of 0.02 mm to 0.16 mm can be used.

  The flame-retardant insulating layer 61 is formed using the flame-retardant resin composition (X). For example, the outer diameter D6c is 0.1 mm or more and 2.0 mm or less, and the wall thickness T6 is 0.05 mm or more and 0. .95 mm or less.

  Such an insulated wire Z1 can be formed using, for example, an extrusion molding apparatus in which a point having a center hole and a die arranged so as to surround the point are set. Specifically, the conductor 60 is moved in a state in which the conductor 60 is inserted into the center hole of the point, while being provided so as to surround the center hole via a resin flow path formed between the point and the die. It can be formed by extruding the flame retardant resin composition (X) from the outlet (discharge port) of the resin flow path. Thus, the insulated wire X1 is formed as the conductor 60 covered with the flame retardant insulating layer 61.

  Here, the flame-retardant adhesive composition (X) used for the formation of the insulated wire Z1 is one in which the [C] phosphorus-based flame retardant is well dispersed as described above. Therefore, extrusion molding when forming the insulated wire Z1 can be appropriately performed. As a result, when the flame-retardant insulating layer 61 is formed thin, for example, even when the thickness T6 is formed to be 0.1 mm (100 μm) or less, extrusion can be appropriately performed. Thereby, by using the flame-retardant adhesive composition (X), it is possible to reduce the thickness of the flame-retardant insulating layer 61 and promote the reduction of the diameter of the insulated wire Z1.

  In addition, since the flame retardant adhesive composition (X) contains a well-dispersed [C] phosphorus flame retardant and an appropriate amount of [B] ionomer, the insulated wire Z1 has flame retardancy, flexibility and It has excellent electrical characteristics, and sufficient adhesion can be ensured between the conductor 60 and the flame-retardant insulating layer 61. Such an effect can be appropriately obtained even when the thickness T6 of the flame-retardant insulating layer 61 of the insulated wire Z1 is reduced to 0.10 mm (100 μm) or less.

<Insulated wire (coaxial cable)>
The insulated wire Z2 of FIGS. 11 and 12 is configured as a coaxial cable. In the coaxial cable Z2, the outside of the conductor 70 is covered with an insulating layer 71 and a protective layer 72.

  As the conductor 70, similarly to the conductor 60 of the insulated wire Z1, a stranded wire obtained by twisting a plurality of strands 73 is used.

  At least one of the insulating layer 71 and the protective layer 72 is formed to have a thickness T7a, T7b of 0.05 mm or more and 0.95 mm or less by, for example, extrusion molding using the flame retardant resin composition (X). . The insulating layer 71 and the protective layer 72 can be formed by extrusion similarly to the flame-retardant insulating layer 61 of the insulated wire Z1. The insulating layer 71 and the protective layer 72 may be formed separately or simultaneously. In the case where the insulating layer 71 and the protective layer 72 are formed separately, the conductor 70 is first covered with the insulating layer 71 in the same manner as the insulated wire Z1 (see FIGS. 9 and 10), and then insulated by performing the same process again. Layer 71 can be covered with a protective layer 72. In this case, before covering the insulating layer 71 with the protective layer 72, an external conductor such as a meshed copper wire may be provided on the surface of the insulating layer 71, and a copper-deposited PET tape may be wound around the surface.

  Here, in the flame-retardant adhesive composition (X) used for forming the insulating layer 71 and / or the protective layer 72 of the coaxial cable Z2, the [C] phosphorus-based flame retardant is well dispersed as described above. It is a thing. Therefore, it is possible to appropriately perform extrusion molding when forming the insulating layer 71 and / or the protective layer 72. As a result, when the insulating layer 71 and / or the protective layer 72 is formed to be thin, for example, even when the thickness is formed to be 0.1 mm (100 μm) or less, extrusion can be appropriately performed. As a result, by using the flame retardant adhesive composition (X), it is possible to promote the reduction in the diameter of the coaxial cable Z2.

  Further, since the flame retardant adhesive composition (X) contains a well-dispersed [C] phosphorus-based flame retardant and an appropriate amount of [B] ionomer, the coaxial cable Z2 has flame retardancy, flexibility and It has excellent electrical characteristics, and sufficient adhesion is ensured between the conductor 70 and the insulating layer 71 and / or between the insulating layer 71 (or external conductor or the like) and the protective layer 72. Such an effect is even when the thickness T7a, T7b of the insulating layer 71 and / or the insulating layer 71 is formed as small as 0.10 mm (100 μm) or less by the flame retardant adhesive composition (X). You can get it properly. As a result, by using the flame retardant adhesive composition (X), the insulating layer 71 and / or the protective layer 72 can be thinned, and the coaxial cable Z2 can be reduced in diameter.

<Flat cable>
The flat cable Z3 of FIGS. 13 and 14 is a cable in which a plurality of aligned (six in this embodiment) insulated wires 80 are collectively covered with a flame-retardant insulating layer 81.

  Such a flat cable Z3 is formed by a method similar to that of the insulated wire Z1, for example, by using the insulated wire 80 instead of the conductor 60 and changing the shape of the dies and points set in the extrusion molding device. be able to. Specifically, as an extrusion molding apparatus, for example, a plurality of points are arranged in a line, and a die is arranged so as to surround these points, so that the outlet of the resin flow path surrounds the center hole of each point. The formed one is used.

  Here, the flame retardant adhesive composition (X) used for the formation of the flame retardant insulating layer 81 of the flat cable Z3 is one in which the [C] phosphorus flame retardant is well dispersed as described above. is there. Therefore, extrusion molding when forming the flame-retardant insulating layer 81 can be performed appropriately. As a result, when the flame-retardant insulating layer 81 is formed to be thin, for example, even when the thickness is formed to be 0.1 mm (100 μm) or less, extrusion can be appropriately performed. Thereby, by using the flame-retardant adhesive composition (X), it is possible to reduce the thickness of the flame-retardant insulating layer 81 and promote the reduction in the thickness of the flat cable Z3.

  Further, since the flame retardant adhesive composition (X) contains a well-dispersed [C] phosphorus-based flame retardant and an appropriate amount of [B] ionomer, the flat cable Z3 has flame retardancy, flexibility and It has excellent electrical characteristics, and sufficient adhesion can be ensured between the conductor 80 and the flame-retardant insulating layer 81. Such an effect can be appropriately obtained even when the thickness T8 of the flame-retardant insulating layer 81 of the flat cable Z3 is reduced to 0.10 mm (100 μm) or less.

<Flat cable>
The flat cable Z4 shown in FIGS. 15 and 16 is obtained by coating a plurality of (six in this embodiment) conductors 90 arranged at intervals with a flame-retardant insulating layer 91.

  Such a flat cable Z4 can be formed by the same method as the flat cable Z3, for example, by changing the shape of a die and a point set in an extrusion molding apparatus.

  Here, the flame retardant adhesive composition (X) used for the formation of the flame retardant insulating layer 91 of the flat cable Z4 is one in which the [C] phosphorus flame retardant is well dispersed as described above. is there. Therefore, extrusion molding when forming the flame-retardant insulating layer 91 can be performed appropriately. As a result, when the flame-retardant insulating layer 91 is formed to be thin, for example, even when the thickness is formed to be 0.1 mm (100 μm) or less, extrusion can be appropriately performed. Thereby, by using the flame-retardant adhesive composition (X), it is possible to reduce the thickness of the flame-retardant insulating layer 91 and promote the reduction of the flat cable Z4.

  Further, since the flame retardant adhesive composition (X) contains a well-dispersed [C] phosphorus-based flame retardant and an appropriate amount of [B] ionomer, the flat cable Z4 has flame retardancy, flexibility and It has excellent electrical characteristics, and sufficient adhesion can be ensured between the conductor 90 and the flame-retardant insulating layer 91. Such an effect can be appropriately obtained even when the thickness T9 of the flame-retardant insulating layer 91 of the flat cable Z4 is reduced to 0.10 mm (100 μm) or less.

  The flame-retardant resin molded product, the insulated wire, and the flat cable of the present invention are not limited to the above embodiment.

  For example, the flame retardant resin molded product of the present invention may be provided with an adhesive layer. For example, an adhesive layer may be provided on the inner surfaces of the heat recovery articles Y1 and Y2, and an adhesive layer may be selectively provided on one side of the insulating film or on an end portion.

  The insulating film as the flame-retardant resin molded body of the present invention is not limited to a rectangular sheet shape and a belt shape, but may be other forms such as a circle. The insulating film is not limited to thermocompression bonding, and may be one that fixes an insulated wire or the like by thermal contraction. As the insulating film in this case, a film whose shape is fixed in a state of being expanded by heating or the like is used like the heat recovery article. The insulating film is not limited to a flat cable and can be widely used for applications that require flame retardancy.

  In the insulated wire of the present invention, a stranded wire is used as a conductor, but a single wire may be used instead of the stranded wire.

  The coaxial cable as the insulated wire of the present invention is not limited to a single-core cable, but can be configured as a multi-core cable.

  The flat cable of the present invention is an insulated wire or a stranded wire as a conductor covered with a flame-retardant insulating layer, but a coaxial cable, a single wire, or the like may be used instead of the insulated wire or the stranded wire. .

  Next, the present invention will be described in more detail based on examples. However, this example does not limit the scope of the present invention.

[Examples 1-8 and Comparative Examples 1-7]
<Preparation of resin composition>
The materials shown in Table 1 and Table 2 were melt-kneaded with a mixer (“TEM26SS”; manufactured by Toshiba Machine Co., Ltd.) to prepare a resin composition. The temperature during kneading was 180 ° C. In addition, the compounding quantity of [C] phosphorus flame retardant and [D] antioxidant is a value when the total mass of [A] polyethylene and [B] ionomer is 100 weight part.

<Production of insulated wires>
The insulated wire was produced using an extruder having a cylinder diameter of 20 mmφ to 30 mmφ.
As the conductor, seven copper wires having a diameter of 0.021 mm were twisted and a stranded wire having a diameter of 0.063 mm was used.
The insulating layer was formed so that the target thickness was 70 μm.
The extrusion speed of the conductor was 100 m / min.

<Evaluation>
[Dispersibility evaluation]
Dispersibility was evaluated by confirming the presence or absence of aggregates by palpating and visually inspecting the surface of the insulated wire produced by the method described above.

[Insulation evaluation]
Insulation is generated per 1000 m of insulated wire when a 5 kV DC voltage is applied using “Spark Tester HF-20-E” (manufactured by Clinton Instrument Company) during the production of the insulated wire (at the time of extrusion molding). Evaluated as the number of sparks made.

[Flame retardance evaluation]
The flame retardancy was evaluated by two types, a vertical test (flame retardance test A) and a horizontal test (flame retardance test B).

(Flame retardance test A)
The flame retardancy test A was performed according to the vertical combustion test defined in “UL Standard 1581 VW-1” using an insulated wire having a length of 500 mm produced by the method described above.
In this vertical combustion test, the portion of 50 mm from the lower end of the insulated wire held vertically is set as the ignition point, and the ignition degree is repeated for 15 seconds by the gas burner and the digestion (pause) for 15 seconds is repeated five times. Examined.
The vertical combustion test is performed on 10 insulated wires, and when all 10 insulated wires satisfy all the following conditions (1) to (3), “pass”, 1 or more insulated wires. Was not satisfied even if any one of the conditions (1) to (3) was satisfied.
(1) Combustion due to after-flame does not exceed 60 seconds (2) Absorbent cotton placed 230 mm below the ignition point in the insulated wire does not burn by burning fallen objects (3) 250 mm above the ignition point in the insulated wire Kraft paper flag does not burn more than 25%

(Flame retardance test B)
The flame retardant test B was performed according to the horizontal combustion test defined in UL standard 1581 using an insulated wire having a length of 700 mm produced by the method described above.
In this horizontal combustion test, the flame of the insulated wire is gently removed after applying the flame of the gas burner to the lower side of the central portion of the insulated wire held horizontally until the insulated wire burns for 30 seconds, and within 60 seconds. To see if it disappears naturally.
When the flame of the insulated wire naturally disappears within 60 seconds after combustion, and when the insulated wire does not burn within 30 seconds, “Pass”, when the flame of the insulated wire does not naturally disappear within 60 seconds after combustion Was "failed".

[Evaluation of conductor adhesion]
Conductor adhesion is about an insulated wire having a length of 50 mm manufactured by the method described above, with the insulating layer peeled off 20 mm from one end to expose the conductor, and the insulated wire covered with the insulating layer only 30 mm from the other end And the tensile strength was measured by the method shown in FIG.
Specifically, first, a die having an inner diameter slightly larger than the outer diameter of the conductor and smaller than the outer diameter of the flame-retardant insulating layer is prepared, and the conductor of the insulated wire is inserted into the hole of the die.
Next, the exposed end portion of the conductor is gripped by the clamp member and the die is gripped by the clamp member, and the die is fixed so as not to move. Then, the conductor was pulled at a speed of 100 mm / min, and the force (kg) required to pull out the conductor was measured.
In this evaluation, the case where the tensile strength was 2 kg or less was determined as “pass”, and the case where the tensile strength exceeded 2 kg was determined as “fail”.

  As shown in Table 1, the insulated wires of Examples 1 to 8 were good in all results of dispersibility evaluation, insulation evaluation, flame retardancy evaluation, and conductor adhesion evaluation.

  On the other hand, as shown in Table 2, the insulated wires of Comparative Examples 1 and 2 did not give good results in the flame retardancy test B (horizontal test) in the flame retardancy evaluation. This is because the conductor diameter of the insulated wire is small, it “passed” the flame retardant test A (vertical test), but because it does not contain [C] phosphorus flame retardant, the flame retardant test B (horizontal test) It is thought that it was “failed”.

  In the insulated wires of Comparative Examples 3 and 4, in the dispersibility evaluation, agglomerates could be confirmed although the appearance was slight. This is considered to be because [B] ionomer was not included, and thus [C] phosphorus-based flame retardant was insufficiently dispersed. In addition, in the insulation evaluation, the occurrence of multiple sparks was confirmed. This is also considered to be caused by insufficient dispersibility of the [C] phosphorus-based flame retardant.

  In the insulated wires of Comparative Examples 5 and 6, the results of the dispersibility evaluation were good. However, in the conductor adhesion evaluation, the adhesion with the conductor was too strong, and it was difficult to peel the insulating layer from the conductor. This is considered to be because although the [B] ionomer was added, the amount added was too large.

  In the insulated wire of Comparative Example 7, agglomerates could be confirmed with a slight appearance in dispersibility evaluation. This is thought to be because although the [B] ionomer is added, the amount of the [C] phosphorus-based flame retardant added is too large. Further, in the conductor adhesion evaluation, it was confirmed that a strong adhesion portion and a weak adhesion portion were generated. This is considered to be caused by the aggregation of the excessively added [C] phosphorus-based flame retardant.

  According to the present invention, since the solid phosphorus flame retardant is satisfactorily dispersed in the flame retardant resin composition, thin wall processing by resin molding such as extrusion molding becomes possible, and flame retardancy and adhesiveness are improved. It becomes possible to provide a flame-retardant resin molded article excellent in flexibility and electrical characteristics, and an insulated wire and a flat cable.

Y1, Y2 Heat recovery article Y3-Y5 Insulating film Z1 Insulated wire 60 Stranded wire (conductor)
61 Flame-retardant insulation layer Z2 Coaxial cable 70 Stranded wire (conductor)
71 Insulating layer 72 Protective layer Z3, Z4 Flat cable 80, 90 Stranded wire (wire)
81, 91 Flame retardant insulation layer

Claims (13)

Contains a resin component containing polyethylene and ionomer and a phosphorus flame retardant,
The phosphorus flame retardant is solid at the melting point of the polyethylene and the ionomer,
The content of the ionomer with respect to the resin component is 3% by mass or more and 30% by mass or less,
The flame-retardant resin composition whose content with respect to 100 mass parts of said resin components of the said phosphorus flame retardant is 5 mass parts or more and 35 mass parts or less.   2. The flame retardant resin composition according to claim 1, wherein the content of the ionomer with respect to the resin component is 5% by mass or more and 20% by mass or less.   The flame-retardant resin composition according to claim 1 or 2, wherein a content mass ratio of the phosphorus-based flame retardant and the ionomer is 100/100 or more and 100/40 or less.   The flame retardant resin composition according to claim 1, 2 or 3, wherein the metal ion of the ionomer is a zinc ion.   The flame retardant resin composition according to any one of claims 1 to 4, wherein the phosphorus flame retardant is a phosphinic acid metal salt.   The flame-retardant resin composition according to any one of claims 1 to 5, wherein the polyethylene is high-density polyethylene.   The flame-retardant resin molding formed from the flame-retardant resin composition of any one of Claims 1-6.   The flame-retardant resin molded product according to claim 7, which is formed to have a thickness of 100 μm or less by extrusion molding.   The flame-retardant resin molded article according to claim 7, which is a heat recovery article.   The flame-retardant resin molded product according to claim 7, which is an insulating film. An insulated wire comprising a conductor and a flame retardant insulating layer covering the outside of the conductor,
The said flame-retardant insulation layer is the flame-retardant resin molding of Claim 7 or Claim 8, The insulated wire characterized by the above-mentioned.   A flat cable in which the plurality of insulated wires according to claim 11 are aligned. A flat cable comprising a plurality of conductors arranged at intervals and a flame-retardant insulating layer covering the outside of these conductors,
A flat cable, wherein the flame-retardant insulating layer is the flame-retardant resin molded body according to claim 7 or 8.

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