JP2002302573A - Flame retardant resin composition and wiring material using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame retardant resin composition and an insulated wire, an optical fiber cable and a molded article having an excellent mechanical property, capable of coloring to an arbitrary color and free from troubles such as elusion of a heavy metal compound and a phosphorus compound caused by a reclamation in scraping and emission of a large quantity of smoke and a corrosive gas in incineration, capable of recycling the material and excellent in mass-productiveness. SOLUTION: This composition is obtained by compounding (a) 100 pts.wt. of a thermoplastic resin including a peroxide curing type thermoplastic polyolefin resin, (c) 0.01-0.6 pts.wt. of an organic peroxide, (d) 0.03-1.8 pts.wt. of (meth)acrylates and/or allylic crosslinking auxiliary and (B) 50-300 pts.wt. of a mixture of metal hydrate and the metal hydrate pretreated with a crosslinking type silane coupling agent, and heating/kneading at a temperature higher than the melting temperature of the thermoplastic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention provides excellent mechanical properties,
Further, the present invention relates to a flame-retardant resin composition having excellent heat resistance, and a wiring material, an optical fiber cord and other molded parts using the composition as a coating material. More specifically, the present invention
An insulated wire used for internal or external wiring of electronic equipment, an insulated wire having excellent pressure contact properties, an electric cable, an electric cord, an optical fiber core, a flame-retardant resin composition suitable as a coating material for an optical fiber cord, and the like. Regarding wiring materials and other molded parts using it, especially a flame-retardant resin composition that does not generate corrosive gas during combustion, is oil-resistant, wear-resistant, is suitable for recycling after use, and is environmentally friendly. The present invention relates to a wiring member and other molded parts using the same.

[0002]

2. Description of the Related Art Insulated wires, cables, optical fiber cores, and optical fiber cords used for internal and external wiring of electric and electronic equipment have flame retardancy, heat resistance, mechanical properties (for example, tensile properties). , Abrasion resistance). For this reason, as a coating material used for these wiring materials, polyvinyl chloride (PVC) compounds and polyolefin compounds containing a halogen-based flame retardant containing bromine atoms and chlorine atoms in the molecule are mainly used. Was. However, when these are burned, a corrosive gas may be generated from a halogen compound contained in the coating material. In recent years, this problem has been discussed, and non-halogen compounds having no fear of generating a halogen-based gas or the like have been discussed. Investigation of wiring materials covered with a fuel material is being conducted. Non-halogen flame-retardant materials express flame retardancy by blending a flame retardant containing no halogen into the resin.
For example, ethylene copolymers such as ethylene / 1-butene copolymer, ethylene / propylene copolymer, ethylene / vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, and ethylene / propylene / diene terpolymer In union,
Materials containing a large amount of metal hydrates such as aluminum hydroxide and magnesium hydroxide as flame retardants have been used for wiring materials.

[0003] However, when aluminum hydroxide or magnesium hydroxide is used as a flame retardant, a large amount of aluminum hydroxide or magnesium hydroxide must be added in order to realize flame retardancy. As a result, there is a problem that the surface of the molded body is easily scratched, and the scratch resistance is greatly reduced. In order to improve the strength, a method of cross-linking the molded article by an electron beam or a chemical cross-linking method is being studied, but if cross-linking is performed, re-molding becomes impossible, and there is a problem that material recycling becomes impossible. .

[0004]

DISCLOSURE OF THE INVENTION The present invention has excellent mechanical properties typified by high scratch resistance, can be colored in any color, and can be used to remove heavy metal compounds and phosphorus compounds by landfilling at the time of disposal. An object of the present invention is to provide a flame-retardant resin composition which is free from problems such as elution, generation of a large amount of smoke and corrosive gas due to incineration, is material recyclable, and is excellent in mass productivity, and a method for producing the same. Another object of the present invention is to provide an insulated wire, an optical fiber cable, and a molded component using the flame-retardant resin composition.

[0005]

SUMMARY OF THE INVENTION The above object is achieved by (1) (a) 100 parts by weight of a thermoplastic resin containing a peroxide-crosslinked thermoplastic polyolefin resin, and (c) an organic peroxide. 0.01 to 0.6 parts by weight, (d) 0.03 to 1.8 parts by weight of the (meth) acrylate and / or allylic crosslinking aid, and 50 to 300 parts by weight of the metal hydrate (B). The metal hydrate (B) contains (i) 50% of the metal hydrate (B).
If the amount is not less than 100 parts by weight and (a) 100 parts by weight of a thermoplastic resin containing a peroxide-crosslinkable thermoplastic polyolefin resin, metal water pretreated with a crosslinkable silane coupling agent is used. (Ii) the metal hydrate (B) is at least 100 parts by weight;
When the amount is not more than 00 parts by weight, at least half of the metal hydrate (B) is a mixture having a composition in which the metal hydrate is pretreated with a crosslinkable silane coupling agent, and the (a) peroxide (2) a flame-retardant resin composition characterized by being heated and kneaded at a temperature not lower than the melting temperature of a thermoplastic resin containing a crosslinked thermoplastic polyolefin resin;
In the flame-retardant resin composition according to the item (1), a polyethylene resin obtained by synthesizing a peroxide-crosslinked thermoplastic polyolefin resin using a single-site catalyst;
(1) The flame retardancy according to (1), wherein at least one selected from the group consisting of a vinyl acetate copolymer, an ethylene-acrylate copolymer and an ethylene methacrylate copolymer is an essential component. (3) The flame-retardant resin composition according to (1) or (2), wherein the thermoplastic resin contains 60% by weight or less of rubber. 3) The flame-retardant resin composition according to any one of the above items, wherein (a) a thermoplastic resin containing a peroxide-crosslinked thermoplastic polyolefin resin, (c) an organic peroxide, and (d) Heating all of the (meth) acrylate-based and / or allylic cross-linking assistants and the metal hydrate (B) above the melting temperature of (a);
Kneading, a method for producing a flame-retardant resin composition, characterized by performing a crosslinking treatment,

(5) The flame-retardant resin composition according to any one of (1) to (3), wherein
(A) After heating and kneading a thermoplastic resin composition containing a peroxide crosslinked thermoplastic polyolefin resin, as a second step, the kneaded product of the first step and (c) an organic peroxide, (d) ) Flame retardancy characterized by heating and kneading (meth) acrylate and / or allylic crosslinking assistants and all of metal hydrate (B) at a melting temperature or higher than (a) and crosslinking. A method for producing a resin composition,
(6) The flame-retardant resin composition according to any one of (1) to (3), wherein (a) a thermoplastic resin composition containing a peroxide-crosslinked thermoplastic polyolefin resin; (C) A part of the organic peroxide and (d) a part of the (meth) acrylate-based and / or allyl-based cross-linking aid are heated and kneaded at a temperature not lower than the melting temperature of (a), and after a crosslinking treatment is performed, A plastic resin composition (A)),
(C) The residue of the organic peroxide, (d) the residue of the (meth) acrylate and / or allylic crosslinking aid and all of the metal hydrate (B) are reheated above the melting temperature of (a). -A method for producing a flame-retardant resin composition characterized by kneading and crosslinking, and (7) the melting temperature of the flame-retardant thermoplastic resin according to any one of (1) to (3) above (a). It is characterized in that the obtained flame-retardant resin composition is obtained as a coating layer on the outside of a conductor or an optical fiber or / and a core of an optical fiber after heating and kneading, and / or after a crosslinking treatment. And (8) (1)-
The flame-retardant resin composition obtained by heating and kneading any of the flame-retardant thermoplastic resins of the item (3) above the melting temperature of (a), and after and / or performing a crosslinking treatment. It is intended to provide a molded part characterized in that:

In the present invention, the amount of the organic peroxide and the amount and type of the crosslinking aid simultaneously contained with the resin component can be appropriately set in the above ranges to provide a loose crosslinked structure having a low crosslinking density. By selecting a specific metal hydrate, it is possible to mix a large amount of metal hydrate, and furthermore, interaction between the metal hydrate surface treatment agent and the resin during the reaction of peroxide during kneading. , The mechanical strength and trauma resistance are improved. Further, by selecting a loose cross-linked structure and a specific metal hydrate, a flame-retardant resin composition and a molded article that can be re-extruded even after cross-linking and are capable of material recycling can be obtained.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, each component of the flame-retardant resin composition of the present invention will be described. (A) Thermoplastic resin

Component (a) Peroxide crosslinked polyolefin resin and / or copolymer rubber containing the same As component (a) used in the present invention, a crosslinking reaction is mainly caused by a heat treatment in the presence of a peroxide. And those whose fluidity is reduced can be used. As the peroxide-crosslinked polyolefin resin and / or a copolymer rubber component containing the same, ethylene / α-olefin copolymer resin, ethylene / α-olefin copolymer rubber, ethylene copolymer, unsaturated carboxylic acid And polyethylene-modified ethylene-α-olefin copolymers and ethylene-based copolymers. The ethylene / α-olefin copolymer is preferably a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms. Specific examples of the α-olefin include propylene,
-Butene, 1-hexene, 4-methyl-1-pentene,
1-octene, 1-decene, 1-dodecene and the like can be mentioned. In the component (a), when the α-olefin is propylene, the content of the propylene component is less than 60%. As the ethylene / α-olefin copolymer resin,
For example, LLDPE (linear low density polyethylene), LD
There are PE (low density polyethylene), VLDPE (ultra low density polyethylene), and ethylene / α-olefin copolymer synthesized in the presence of a single-site catalyst. Among these, an ethylene / α-olefin copolymer synthesized in the presence of a single-site catalyst is preferable in consideration of the receptivity of the filler to be filled and the flexibility of the resin composition aimed at by the present invention. The density is preferably 0.895 or more in consideration of oil resistance and wear resistance. In consideration of flexibility, it is preferably 0.93 g / cm ³ or less, more preferably 0.925 g / cm ³ or less, and particularly preferably 0.99 g / cm ³ or less.
It is 2 g / cm ³ or less. Although there is no particular lower limit on the density, the lower limit is usually 0.850 g / cm ³ . The ethylene / α-olefin copolymer preferably has a melt flow index (ASTM D-1238) of 0.5 to 30 g / 10 minutes.

The ethylene / α-olefin copolymer synthesized in the presence of a single-site catalyst according to the present invention comprises:
As the production method, a known method described in JP-A-6-306121 or JP-T-7-500622 can be used. Single-site catalysts
It has a single polymerization active point and has high polymerization activity, and is also called a metallocene catalyst or a Kaminsky catalyst.An ethylene / α-olefin copolymer synthesized using this catalyst has a molecular weight distribution and It is characterized by a narrow composition distribution. Since the ethylene / α-olefin copolymer synthesized in the presence of such a single-site catalyst has high tensile strength, tear strength, impact strength, and the like, it is necessary to fill the metal hydrate at a high level. When used as a fuel material (coating material for wiring material), there is an advantage that deterioration of mechanical properties due to highly filled metal hydrate can be reduced. On the other hand, when an ethylene / α-olefin copolymer synthesized using a single-site catalyst is used, the melt viscosity increases and the melt tension decreases as compared with the case where a normal ethylene / α-olefin copolymer is used. This causes a problem in molding workability. In this regard,
Introduction of long-chain branching using an asymmetric catalyst as a single-site catalyst (Constrained Geometo)
ry Catalytic Technology),
Alternatively, two peaks are created in the molecular weight distribution by connecting two polymerization tanks during the synthesis (Advanced Pe).
rformance Terpolymer)
Some of them have improved formability.

As the ethylene / α-olefin copolymer synthesized in the presence of a single-site catalyst used in the present invention, those having improved moldability are preferable, and such an ethylene / α-olefin copolymer is preferably Dow Chemical.
"AFFINITY" and "ENGAGE"
(Product name) from Exxon Chemical Company,
"EXACT" (trade name), "Kernel" (trade name) from Polychem, "Yumerit" from Ube Industries, Ltd.
Has been launched. As the rubber used in the present invention, an ethylene-α-olefin copolymer rubber is preferable. Examples of the ethylene-α-olefin copolymer rubber include an ethylene-propylene copolymer rubber. Ethylene-propylene copolymer rubber (EPM) is a rubbery copolymer of ethylene and propylene. Here, the ethylene / propylene copolymer rubber has an ethylene component content of usually 40 to
About 75% by weight. Ethylene-propylene terpolymer (EP) in which a polymer is provided with a repeating unit having an unsaturated group as a third component other than ethylene and propylene
DM), but in the present invention, E having no double bond
It is necessary to use PM. This is because when EPDM is used, the elongation is reduced, and the extrudability is significantly impaired. EPM may be used alone,
You may mix and use 2 or more types. The content of the ethylene component in the ethylene-propylene copolymer rubber is suitably from 85 to 40% by weight. Preferably it is 80 to 45% by weight, more preferably 75 to 50% by weight. If the ethylene component content is too small, the flexibility of the obtained resin composition will be insufficient, and if it is too large, the mechanical strength will decrease.
Mooney viscosity of ethylene-propylene copolymer rubber, M
L _{1 + 4} (100 ° C.) is preferably 10 to 120, more preferably 40 to 100. If the Mooney viscosity is less than 10, the resulting elastomer composition may have poor rubber elasticity. Further, when the amount exceeds 120, molding processability may be deteriorated, and in particular, appearance of a molded product is deteriorated. The amount of the ethylene-propylene copolymer rubber in the thermoplastic resin component (A) is preferably 0 to 30% by weight, more preferably 0 to 25% by weight.

By adding the ethylene-propylene copolymer rubber component, flexibility is remarkably improved, a large amount of metal hydrate can be added, and flame retardancy can be further improved. If this ethylene-propylene rubber is added in an amount of more than 30 parts by weight, the extrudability will be significantly reduced, and the oil resistance will be significantly reduced. Examples of the ethylene copolymer include an ethylene-vinyl acetate copolymer, an ethylene- (meth) acrylic acid copolymer, and an ethylene- (meth) acrylate copolymer (for example, an ethylene-butyl acrylate copolymer, Ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer) and the like. By using an ethylene copolymer, flame retardancy can be improved. In order to further improve the flame retardancy, the content of the copolymer component other than ethylene is preferably at least 23% by weight, more preferably at least 25% by weight, further preferably at least 28% by weight. Among the ethylene copolymers, an ethylene-vinyl acetate copolymer is preferred from the viewpoint of improving flame retardancy. To ensure vertical flame retardancy, vinyl acetate (V
A) The component content is 30% by weight or more, further 40% by weight
Those described above are preferred. Also, the compounding amount is preferably 50% by weight or more. MFR is 0.3
g / 10 minutes or more, and preferably 30 g / 10 minutes or less from the viewpoint of maintaining strength. Among peroxide-crosslinked thermoplastic polyolefin resins and / or rubbers, polyethylene resins, ethylene-vinyl acetate copolymers, ethylene-acrylate copolymers, ethylene methacrylate copolymers synthesized using a single-site catalyst are used. Polymers are preferred.

Component (c) Organic peroxide Examples of the organic peroxide used in the present invention include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (te
rt-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butyl) Butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-
Chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butylcumyl peroxide and the like can be mentioned. Among them, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane and 2,5-dimethyl-2,5-di- ( (tert-Butylperoxy) hexyne-3 is most preferred. The compounding amount of the organic peroxide (c) depends on the thermoplastic resin component (A).
It is in the range of 0.01 to 0.6 part by weight, preferably 0.02 to 0.5 part by weight, per 100 parts by weight. By selecting organic peroxide within this range,
Since cross-linking does not proceed too much, a partially cross-linked composition having excellent extrudability without blemishes can be obtained. On the other hand, if it is less than the lower limit, the scratch resistance is poor.

Component (d) (Meth) acrylate and / or allylic crosslinking aid In the production of the flame-retardant resin composition of the present invention or the thermoplastic resin component used therefor, the crosslinking aid is preferably used in the presence of an organic peroxide. A partially crosslinked structure is formed between the agents. In this case, as a crosslinking aid, a general formula

[0015]

Embedded image

(Where R is H or CH ₃ and n is an integer of 1 to 9). Here, the (meth) acrylate-based crosslinking aid refers to an acrylate-based and methacrylate-based crosslinking assistant. Specific examples include ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and allyl methacrylate. In addition, those having an allyl group at the terminal such as diallyl fumarate, diallyl phthalate, tetraallyloxyethane, and triallyl cyanurate can be used. Among them, (meth) acrylate-based crosslinking assistants in which n is 1 to 6 are particularly preferable, and examples thereof include ethylene glycol diacrylate, triethylene glycol dimethacrylate, and tetraethylene glycol dimethacrylate.

In particular, in the present invention, triethylene glycol dimethacrylate is easy to handle, has good compatibility with other components, has a peroxide solubilizing action, and acts as a peroxide dispersing aid. For,
This is most preferable because the crosslinking effect at the time of heating and kneading is uniform and effective, and a partially crosslinked thermoplastic resin having a balance between hardness and rubber elasticity can be obtained. By using such a compound, neither insufficient crosslinking nor excessive crosslinking occurs, and a uniform and efficient partial crosslinking reaction can be expected at the time of heating and kneading. The addition amount of the crosslinking aid used in the present invention is preferably in the range of 0.03 to 1.8 parts by weight, more preferably 0.09 to 1.5 parts by weight, based on 100 parts by weight of the thermoplastic resin component. It is. By selecting the crosslinking aid within this range,
The composition becomes a gentle crosslink without excessively progressing the crosslink, and a composition having excellent extrudability without producing lumps can be obtained. The compounding amount of the crosslinking assistant is preferably about 1.5 to 4.0 times the amount of the organic peroxide to be added in weight ratio.

(B) Metal Hydrate The metal hydrate used in the present invention is not particularly limited. Examples thereof include aluminum hydroxide, magnesium hydroxide, aluminum silicate hydrate, magnesium silicate hydrate, and basic hydrate. Compounds having hydroxyl groups or water of crystallization such as magnesium carbonate and hydrotalcite can be used alone or in combination of two or more. Of these metal hydrates, aluminum hydroxide and magnesium hydroxide are preferred. The metal hydrate needs to be at least partially treated with a crosslinkable silane coupling agent, but is treated with another surface treatment agent such as an untreated metal hydrate or fatty acid that has not been surface-treated. A metal hydrate can be appropriately used in combination.

Examples of the crosslinkable silane coupling agent used for the surface treatment of the metal hydrate include vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, Vinyl groups (including those containing double bonds such as methacryl groups and acrylic groups) such as glycidoxypropylmethyldimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, and methacryloxypropylmethyldimethoxysilane; or Epoxy-terminated silane coupling agents, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane and other mercapto-terminated silane coupling agents, aminopropyltriethoxysila Having an amino group such as aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltripropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltripropylmethyldimethoxysilane Crosslinkable silane coupling agents such as silane coupling agents are preferred. Further, two or more of these silane coupling agents may be used in combination. Among such crosslinkable silane coupling agents, a silane coupling agent having an epoxy group at the terminal and / or a vinyl group having a double bond at the terminal as described above is more preferable. Two or more kinds may be used in combination.

Examples of the surface-treated magnesium hydroxide which can be used in the present invention include those having no surface treatment (commercially available products such as Kisuma 5 (trade name, manufactured by Kyowa Chemical Co., Ltd.)), stearic acid, and the like. A silane coupling agent having a vinyl group or an epoxy group at the end of a product surface-treated with a fatty acid such as oleic acid (Kisuma 5A (trade name, manufactured by Kyowa Chemical Co., Ltd.), etc.) or a product treated with a phosphate ester Commercially available magnesium hydroxide (Kisuma 5LH, Kisuma 5PH (both trade names, manufactured by Kyowa Chemical Co., Ltd.), etc.) ). In addition, in addition to the above, a silane coupling having a functional group such as a vinyl group or an epoxy group at the end of magnesium hydroxide or aluminum hydroxide, the surface of which is partially pretreated with a fatty acid or a phosphate ester in advance. Metal hydrates and the like that have been surface-treated with an agent can also be used. At the same time, metal hydrates and the like that have been subjected to surface treatment using a fatty acid or a phosphoric acid ester and a silane coupling agent having a functional group such as a vinyl group or an epoxy group at the terminal can also be used.

When treating a metal hydrate with a crosslinkable silane coupling agent, it is necessary to previously blend the crosslinkable silane coupling agent with the metal hydrate. At this time, the crosslinking silane coupling agent is appropriately added in an amount sufficient for surface treatment, and specifically, is preferably 0.2 to 2% by weight based on the metal hydrate. The crosslinkable silane coupling agent may be a stock solution or a solution diluted with a solvent.

The amount of the metal hydrate is from 50 to 100 parts by weight of the thermoplastic resin component in the resin composition of the present invention.
It is 300 parts by weight, particularly preferably 100 to 280 parts by weight. In the present invention, when (i) the metal hydrate is 50 parts by weight or more and less than 100 parts by weight, 50 parts by weight or more based on 100 parts by weight of the thermoplastic resin component, and (i)
i) When the metal hydrate is 100 parts by weight or more, at least half of the metal hydrate is pretreated with a crosslinkable silane coupling agent to reduce the strength even when a large amount of the metal hydrate is added. Does not occur, and a large amount of filler can be blended with the resin. At least one metal hydrate
It is particularly preferred that 00 parts by weight is magnesium hydroxide treated with a crosslinkable silane coupling agent. If the amount of the silane-treated metal hydrate is smaller than the predetermined amount, not only the mechanical strength is reduced, but also the scratch resistance is significantly reduced. Also, the heat aging characteristics are reduced. Further, when more than 300 parts by weight of the metal hydrate is added, the mechanical strength, elongation, scratch resistance, and extrudability are significantly reduced.

When a general polyolefin resin such as a polyethylene resin or a polypropylene resin is used as a base resin, and a large amount of a metal hydrate is added to satisfy the required flame retardancy, the mechanical strength is reduced. Very large.
Particularly, in the case of (a) a resin composition composed of a peroxide-crosslinked thermoplastic polyolefin resin and / or rubber, when a large amount of metal hydrate is added, the mechanical strength and elongation are extremely reduced. large. On the other hand, the (a) peroxide-crosslinked thermoplastic polyolefin resin and / or rubber in the present invention has a low crosslink density and some of the molecular chains are partially crosslinked via the component (d). Further, since a crosslinkable silane coupling agent surface-treated on a metal hydrate and (a) a peroxide crosslinked thermoplastic polyolefin resin and / or rubber form a network structure, Even if a large amount of the compound is blended, a decrease in elongation and a decrease in strength hardly occur. Further, when the composition molded body is bent, whitening hardly occurs,
Further, since the filler is not peeled off, the trauma resistance is greatly improved. Furthermore, in the present invention, the resin composition is formed without containing a polymer having an aromatic residue, and further partially crosslinked, and furthermore,
Since the metal hydrate component and the polymer component have a network structure, it is possible to obtain an insulating resin composition and an insulated wire that can maintain extremely excellent oil resistance. Also, in the case of an elastomer molded article using a polymer having an aromatic substance, for example, a styrene-based elastomer, process oil is used as a processing agent and a softening agent. Causes a decline in sex. A decrease in the adhesiveness of an epoxy resin or the like may cause a problem when processing a terminal of an electric wire or an optical cord. Further, in the resin composition of the present invention, the peroxide-crosslinked polyolefin resin of the component (a) is in a partially crosslinked state via the component (d), and a crosslinkable silane cup surface-treated on a metal hydrate. Since the ring agent and the peroxide-crosslinked polyolefin resin of the component (a) form a network structure, they are also excellent in abrasion resistance and the like.

The details of the reaction mechanism at the time of heating and kneading the resin composition of the present invention are not yet clear, but are considered as follows. That is, the component (a) in the present invention comprises:
When heated and kneaded, it is crosslinked via component (d) in the presence of component (c), and component (a) interacts with magnesium hydroxide via a crosslinkable silane coupling agent. Become. Although the crosslinking reaction by the peroxide is not clearly understood, the reaction between the component (a) and the crosslinkable silane coupling agent is faster because the reaction between the component (a) and the crosslinkable silane coupling agent is faster. However, it is considered that the reaction is more dominant than the crosslinking reaction between the components (a) via the component (d). Further, since the crosslinked structure is very loose, the crosslinking between the components (a) via the component (d) is very gentle, and the composition as a whole is a crosslinked product having excellent extrudability. The crosslinking of the composition of the present invention may be performed in the presence of a small amount of the component (c),
Since the number of crosslinking points is smaller than that of ordinary crosslinking, it can be referred to as partial crosslinking.

The degree of crosslinking of the flame-retardant resin composition can be represented by a gel fraction and a dynamic elastic modulus of the thermoplastic resin component as a guide. The gel fraction can be expressed by a ratio of the weight of the residual solid content to 1 g of the sample after wrapping 1 g of the sample in a 100-mesh wire mesh and extracting it in boiling xylene using a Soxhlet extractor for 10 hours. The dynamic elastic modulus can be represented by a storage elastic modulus of melt viscoelasticity using a parallel plate. In the present invention, the degree of crosslinking is preferably 5 to 40% by weight, more preferably 10 to 40% by weight in terms of gel fraction.
-35% by weight, preferably 105-107 in storage modulus.
Pa. When the thermoplastic resin component (A) is filled with a metal hydrate, at the same time as the components (c) and (d),
Only when a specific amount of the metal hydrate treated with the silane coupling agent is added, it is possible to mix a large amount of the metal hydrate without impairing the extrusion processability during molding, resulting in excellent flame retardancy It is possible to obtain a flame-retardant resin composition which has both heat resistance and mechanical properties while securing the property, and which can be re-extruded after use and can be recycled.

The mechanism by which the metal hydrate treated with the silane coupling agent acts is not yet clear, but is considered as follows. That is, the silane coupling agent bonded to the surface of the metal hydrate by treating with the silane coupling agent has one of the alkoxy groups bonded to the metal hydrate and the vinyl or epoxy group existing at the other end. Various reactive sites such as the first bond with the peroxide-crosslinked uncrosslinked portion of the component (a). This makes it possible to mix a large amount of metal hydrate without impairing the extrusion moldability, the adhesion between the resin and the metal hydrate becomes strong, and the mechanical strength and wear resistance are good, A flame-retardant resin composition that is resistant to damage is obtained.
Normally, even when the components (a), (c) and (d) are added in predetermined amounts, the reaction at the time of heating and kneading called partial cross-linking as in the present invention is not carried out, or the cross-linkable silane coupling material is used. If the metal hydrate is not used,
Not only does the mechanical strength decrease, but it is not possible to obtain an electric wire having excellent oil resistance, abrasion resistance and excellent pressure contact properties as in the present invention. Although it is not clear how these properties are obtained in the present invention, since the metal hydrate forms a network with the peroxide-crosslinked polyolefin resin of the component (a), the entire composition becomes rigid. It is considered that oil resistance and abrasion resistance were dramatically improved.

The flame-retardant resin composition of the present invention contains various additives generally used in electric wires, electric cables and electric cords, for example, antioxidants, metal deactivators, flame retardants ( Auxiliary agents, fillers, lubricants, acid anhydrides and modified products thereof can be appropriately compounded within a range not to impair the object of the present invention. As antioxidants, amine antioxidants such as polymers of 4,4'-dioctyl diphenylamine, N, N'-diphenyl-p-phenylenediamine, and 2,2,4-trimethyl-1,2-dihydroquinoline Agent, pentaerythrityl-tetrakis (3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionate, 1,3,5-
Phenolic antioxidants such as trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, bis (2-methyl-4- (3-n-alkylthiopropionyloxy) ) -5-t-butylphenyl) sulfide, 2-mercaptobenzimidazole and its zinc salt, and sulfur-based antioxidants such as pentaerythritol-tetrakis (3-lauryl-thiopropionate). As metal deactivators,
N, N'-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3-
(N-salicyloyl) amino-1,2,4-triazole, 2,2′-oxamidobis- (ethyl 3- (3,5-
Di-t-butyl-4-hydroxyphenyl) propionate).

Further, as a flame retardant (auxiliary) agent and a filler, carbon, clay, zinc stannate, zinc oxide, tin oxide, titanium oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, talc, Examples thereof include calcium carbonate, magnesium carbonate, zinc borate, and white carbon. Examples of the lubricant include hydrocarbons, fatty acids, fatty acid amides, esters, alcohols, and metallic soaps. Silicone resin can be used as the surface smoothing material. The use of a silicone resin further improves the press workability. Examples of the silicone compound include ordinary silicone oil having a linear siloxane structure, silicone rubber using polydiorganosiloxane as a main material, silicone gum as a main material of the silicone rubber, and powdery silicone resin. Among these, silicone gum is desirable because it is the main raw material of silicone rubber. Among silicone gums, silicone gums having a cross-linking group such as a vinyl group in a side chain are desirable. The basic molecular structure of silicone gum includes those having a methyl group, vinyl group, and phenyl group in the side chain of siloxane, but other alkyl groups, alkenyl groups, and other aromatic groups can also be selected. is there. The use of silicone gum having a cross-linking group such as a vinyl group in the side chain allows the silicone gum to bond with other polymers or silane-treated metal hydrate in a gradual cross-linking reaction during compounding. , No bleed,
Moreover, an electric wire having excellent surface smoothness can be obtained.

As other compounding agents, a reinforcing filler, a plasticizer, a bulking filler, an additive, a crosslinking agent, and the like may be added to the silicone gum. Degree of polymerization 5 as silicone gum
Although those having a degree of polymerization of lower than about 000 to 10,000 are preferred, those having a lower polymerization degree may be used. Also, instead of this silicone gum and the like, for example, polyethylene grafted with silicone, polyolefin such as polypropylene,
An ethylene-based copolymer such as an ethylene-vinyl acetate copolymer or an ethylene-methyl acrylate copolymer, or a polyolefin or an ethylene copolymer in which silicone is previously mixed may be added.

The additives and other resins can be introduced into the flame-retardant resin composition of the present invention as long as the object of the present invention is not impaired. At least the component (a) is used as a main resin component. I do. Here, the term “main resin component” refers to the resin component of the flame-retardant resin composition of the present invention, which is usually 70% by weight or more.
Preferably, the component (a) accounts for 85% by weight or more, and more preferably the total amount of the resin component.

Hereinafter, the method for producing the flame-retardant resin composition and the wiring member of the present invention will be described. In the first step, first, the total amount of the component (a), at least a part of the component (B) (preferably 50 to 100% by weight, more preferably 70 to 100% by weight, based on the amount of (B) used), and in some cases, Further, various additives such as a filler, an antioxidant, a light stabilizer, and a colorant are melt-kneaded in advance. The kneading temperature is preferably 160 to 24.
0 ° C. As a kneading method, a method usually used for rubber, plastics and the like can be used satisfactorily. For example, a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, various kneaders and the like are used. By this step, a composition in which each component is uniformly dispersed can be obtained. In the second step, the composition obtained in the first step is
The components (c) and (d) are added, and the mixture is further kneaded under heating to cause partial crosslinking. The temperature at this time is preferably 180 to 240 ° C. As described above, the components (a) and (B) are melt-kneaded in advance to cause micro-dispersion, and then the components (c) and (d) are added and kneading is performed under heat treatment to obtain a partially crosslinked product. The formation results in particularly preferred physical properties. This step can be generally performed by a method of kneading using a twin-screw extruder, a Banbury mixer, or the like. The first and second steps may be a single step, and the respective components may be mixed and melt-kneaded. In the third step, the remaining amount of each component is added to the partially crosslinked composition obtained in the second step and kneaded. The kneading temperature is preferably from 180 to 240 ° C. Kneading is
Generally, it can be carried out using a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer or various kneaders. In this step, the reaction is completed at the same time as the dispersion of each component further proceeds. It is also possible to combine the first, second and third steps into a single step, and to melt-knead the components at once. Further, the total amount of the component (B) may be added in the first step, and then the flame retardant resin composition of the present invention may be obtained through the second step.

The flame-retardant resin composition of the present invention is suitable for coating and manufacturing molded parts such as wiring materials used for internal and external wiring of electric / electronic devices, optical fiber cores and optical fiber cords. When the resin composition of the present invention is used as a coating material for a wiring material, preferably, at least one coating layer formed of the flame-retardant resin composition of the present invention formed on the outer periphery of a conductor by extrusion coating. There is no particular limitation other than having, for example, as the conductor, a known arbitrary one such as a soft copper single wire or a stranded wire can be used. Further, as the conductor, in addition to the bare wire, a tin-plated conductor or a conductor having an enamel-coated insulating layer may be used. The wiring member of the present invention can be produced by extrusion-coating the flame-retardant resin composition of the present invention around a conductor or an insulated wire using a general-purpose extrusion coating device. At this time, the temperature of the extrusion coating apparatus was about 180 ° C. in the cylinder section and about 2 ° C. in the crosshead section.
Preferably, the temperature is set to about 00 ° C. In the wiring member of the present invention, the thickness of the insulating layer (coating layer made of the flame-retardant resin composition of the present invention) formed around the conductor is not particularly limited, but is usually about 0.15 mm to 5 mm.

In the wiring material of the present invention, it is preferable that the resin composition of the present invention is extrusion-coated to form a coating layer as it is. However, in order to further improve heat resistance, the coating after extrusion is preferably used. It is also possible to crosslink the layers. However, when this cross-linking treatment is performed, it is difficult to reuse the coating layer as an extruded material. As a method for performing crosslinking, an electron beam irradiation crosslinking method or a chemical crosslinking method according to a conventional method can be employed. In the case of the electron beam crosslinking method, crosslinking is performed by irradiating an electron beam by a conventional method after extruding a resin composition to form a coating layer. The dose of electron beam is 1 to 30 Mrad
In order to efficiently perform crosslinking, the resin composition constituting the coating layer is preferably a methacrylate compound such as trimethylolpropane triacrylate, an allyl compound such as triallyl cyanurate, a maleimide compound, or a divinyl compound. A polyfunctional compound such as a compound may be blended as a crosslinking aid. In the case of the chemical cross-linking method, an organic peroxide is compounded as a cross-linking agent in the resin composition, and after extrusion molding to form a coating layer, cross-linking is performed by a heat treatment in a conventional manner.

The optical fiber core wire or the optical cord of the present invention is formed by using a flame-retardant resin composition of the present invention as a coating layer around an optical fiber or a tensile strength fiber using a general-purpose extrusion coating apparatus. Is extruded around a stranded or twisted optical fiber core.
At this time, the temperature of the extrusion coating apparatus was 18
It is preferable that the temperature is 0 ° C. and about 200 ° C. in the crosshead portion. The optical fiber core wire of the present invention is used as it is without providing a coating layer further around depending on the application. In addition, the optical fiber core wire or cord of the present invention includes all of the flame retardant resin composition of the present invention as a coating layer coated on the outer periphery of the optical fiber wire or the core wire, and the structure thereof is particularly limited. It does not do. The thickness of the coating layer, the type of tensile strength fiber to be vertically laid or twisted on the optical fiber core,
The amount and the like differ depending on the type and use of the optical fiber cord, and can be appropriately set.

2 to 4 show examples of the structure of the optical fiber cable and cord according to the present invention. FIG. 2 is a cross-sectional view of one embodiment of the optical fiber core of the present invention in which a coating layer 2 made of a flame-retardant resin composition is provided directly on the outer periphery of an optical fiber 1.
FIG. 3 is a cross-sectional view of one embodiment of the optical fiber cord of the present invention in which a coating layer 5 is formed on the outer periphery of one optical fiber core wire 3 to which a plurality of tensile fibers 4 are longitudinally attached. FIG. 4 shows an optical fiber cord (optical fiber two-core cord) of the present invention in which a plurality of tensile strength fibers 4 are vertically attached to the outer periphery of two optical fiber cores 3 and 3 and a coating layer 6 is further formed on the outer periphery thereof. FIG.

The shape of the molded part of the present invention is not limited, and examples thereof include a power plug, a connector, a sleeve, a box, a tape base, a tube, a sheet and the like. The molded part of the present invention is molded from the flame-retardant resin composition of the present invention by a usual molding method such as injection molding.

[0037]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. In addition, numerals show a weight part unless there is particular description.

As the component (a), the ethylene-α olefin copolymer, maleic acid-modified polyethylene, ethylene vinyl acetate copolymer described in the table, and as the component (c), 2,5-dimethyl-2,5-di (t- Using butylperoxy) -hexane, triethylene glycol dimethacrylate as the component (d), and magnesium hydroxide as the component (B), the components were prepared in the amounts shown in Tables 1 and 2 to prepare compositions.

In Examples and Comparative Examples, all components were dry-blended at room temperature, heated and kneaded at 200 ° C. using a Banbury mixer, and discharged to obtain a flame-retardant resin composition. The discharge temperature was 200 ° C.

From the obtained resin composition,
1 mm sheets corresponding to the respective examples, reference examples, and comparative examples were prepared. Next, a conductor (conductor diameter: 1.14 mmφ tinned soft copper stranded wire) was formed using an extrusion coating apparatus for manufacturing an electric wire.
30 pieces / 0.18 mmφ), extrusion-coated with a resin composition for insulating coating melted in advance, and an outer diameter of 2.74 m
m of insulated wires were manufactured. For each obtained sheet,
The tensile properties (elongation (%) and tensile strength (MPa)) were measured, and the results are shown in Tables 1 and 2. Regarding each property of the sheet, elongation was 100% or more and tensile strength 10 MPa or more was accepted.

The coating layer of the insulated wire having an outer diameter of 2.74 mm was subjected to tensile properties, a horizontal burning test, a heat aging test, a trauma resistance, and an extrudability test to evaluate each characteristic. The results are also shown in Table 2. The tensile properties were measured by measuring the tensile strength (MPa) and elongation at break (%) of the insulator (coating layer) of each insulated wire under the conditions of a mark interval of 25 mm and a tensile speed of 500 mm / min. Elongation is 100% or more, strength is 10M
Pa or more is required. The heat aging test was performed at 90 ° C. for 96 hours. Residual elongation is 65% or more, residual tensile strength is 8
0% or more is required.

In the horizontal combustion test, J
A horizontal combustion test defined in ISC 3005 was performed, and those that self-extinguished within 30 seconds were counted as pass, and the number of passes out of 10 was indicated. The scratch resistance was determined by rubbing the 90-degree edge three times with a force of 3N to determine the presence or absence of scratches. No or small trauma, X: trauma is clearly observed.
The extrudability test was performed by extruding with a 30 mmφ extruder, and the motor load could be extruded within the normal range, and those with good appearance were evaluated as ○. Those having extremely large extrusion loads and difficult or impossible extrusion were evaluated as x. △ or above is a level that has no practical problem and is acceptable.

Each of the compounds shown in the table is as follows:
used. (A) Thermoplastic resin component Component (a): peroxide-crosslinked polyolefin (a-1) Single-site catalytic ethylene / α-olefin
In (butene) copolymer Manufacturer: Nippon Polychem Co., Ltd. Product name: KF-360 Density: 0.898 g / cm^Three  (A-2) Ethylene vinyl acetate copolymer Manufacturer: Mitsui DuPont Polychemicals Product name: V-421 VA content: 28% by weight (a-3) Ethylene vinyl acetate copolymer Manufacturer: Mitsui Dupont Polychemical Product name: V-527-4 VA content: 17% by weight (a-5) Ethylene propylene rubber Manufacturer: JSR Product name: EP07P (a-6) Maleic acid-modified polyethylene Manufacturer: Mitsui Chemicals, Inc. Name: Admer XE070

Component (c): Organic peroxide Manufacturer: Nippon Yushi Co., Ltd. Product name: Perhexa 25B Type: 2,5-dimethyl-2,5-di (t-butylperoxy) -hexane Component (d): Crosslinking Auxiliary agent Manufacturer: Shin-Nakamura Chemical Co., Ltd. Product name: NK ester 3G Type: Triethylene glycol dimethacrylate (B) metal hydrate Manufacturer: Kyowa Chemical Co., Ltd. Product name: Kisuma 5LH Type: Having a vinyl group at the terminal Magnesium hydroxide surface-treated with silane coupling agent Manufacturer: Kyowa Chemical Co., Ltd. Product name: Kisuma 5B Type: Fatty acid-treated magnesium hydroxide Other components Phenolic antioxidant Manufacturer: Ciba Geigy Corporation Product name: Irganox 1010 : Pentaerythrityl-tetrakis (3- (3,5
-Di-t-butyl-4-hydroxyphenyl) propionate)

[0045]

[Table 1]

[0046]

[Table 2]

As is evident from the results in the table, the flame-retardant resin composition obtained in the examples, and the sheets and electric wires using the same, have the required elongation and tensile strength, are subjected to a combustion test, and are extruded. It was also excellent. In addition, due to the elongation, tensile strength, wear resistance, and extrudability of the electric wires shown in Tables 1 and 2, the flame-retardant resin composition of the present invention is also suitable for coating electric wires, optical fiber cords and optical fiber cores. It can be seen that it can be used for

The covering material formed in Example 2 was removed, and this was passed through a round pelletizer, pelletized, and again covered with an outer diameter of 2.74 mm around a 30 / 0.18 conductor to prepare an electric wire. . The physical properties of the obtained electric wire are as shown in Table 3 below, and hardly changed from the physical properties of the electric wire of Example 2. Thus, the material of the present invention can be recycled.

[0049]

[Table 3]

[0050]

According to the present invention, flame retardancy, heat resistance, and mechanical properties are excellent, and no corrosive gas is generated at the time of disposal such as combustion. A resin composition and a wiring material can be provided. Furthermore, according to the present invention, while satisfying these characteristics, the coating material can be re-melted because it can be re-melted, and the flame-retardant resin composition and the wiring material using the same, which are hardly damaged, an optical fiber core, Optical fiber cords and other molded parts may be provided. Also,
The wiring member of the present invention has excellent mechanical properties, flame retardancy and heat resistance, as well as excellent oil resistance and wear resistance. Furthermore, it is excellent in pressure welding workability. As described above, the wiring material of the present invention has excellent properties as a non-halogen flame-retardant wiring material containing no phosphorus, which can achieve both flexibility and mechanical strength. Furthermore, since the coating layer of the wiring material of the present invention can be formed by using a remeltable material as the coating material while having high heat resistance, the wiring coated with the crosslinked product which is the current coating material is used. As a result, it is possible to provide a wiring material that is more recyclable than a material. From the above, the wiring material of the present invention is an electric and
It is very useful as a wiring material for electronic devices, for example, a power cable. The flame-retardant resin composition of the present invention is also suitable as a coating material for such wiring materials, optical fiber cores, optical fiber cords, and the like, as a material for molded parts, and also as a tube or tape material. It is something.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of an optical fiber core of the present invention in which a coating layer is provided directly on the outer periphery of an optical fiber.

FIG. 2 is a cross-sectional view of one embodiment of the optical fiber cord of the present invention in which a coating layer is formed on the outer periphery of one optical fiber core wire to which a plurality of tensile fibers are longitudinally attached.

FIG. 3 is a cross-sectional view of another embodiment of the optical fiber cord of the present invention in which a plurality of tensile fibers are vertically attached to the outer periphery of two optical fiber cores and a coating layer is further formed on the outer periphery thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber wire 2 Coating layer 3 Optical fiber core wire 4 Tensile fiber 5 Coating layer 6 Coating layer 7 Insulated electric wire 7a Insulating coating layer 7b Conductor 8 units 9 Clamp 10 Load 11 Blade 11a, 11b Blade surface of blade 12 Electric wire sample

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 9/04 C08K 9/04 G02B 6/44 301 G02B 6/44 301A // (C08L 23/00 C08L 21 : 00 21:00) B29K 23:00 B29K 23:00 31:00 31:00 33:04 33:04 (72) Inventor Ken Okubo 3-8-5-505 505 Nagasawa, Tama-ku, Kawasaki City, Kanagawa Prefecture 505 (72) Inventor Shinichi Kishimoto 1-9-9 Higashi-Kojiya, Ota-ku, Tokyo F-term (reference) 2H050 BB07W BB10W BB17W BB19W BB35W BC17 BD03 4F201 AA03 AA04 AA10 AA10E AA21E AB03 AB05 AB16 AH35 BA01 BC01 BC12 BB37 BB03 BB01 BB01 BB01 BB01 BB01 DE078 DE148 DE238 DE288 DJ008 ED027 EH077 EH127 EK006 EK036 EU197 FB098 FD147

Claims (8)

[Claims] 1. A thermoplastic resin 100 comprising (a) a peroxide-crosslinked thermoplastic polyolefin resin.
(C) Organic peroxide 0.01 to 100 parts by weight
0.6 parts by weight, (d) (meth) acrylate type and / or
Or 0.03 to 1.8 parts by weight of an allylic crosslinking aid and 50 to 300 parts by weight of a metal hydrate (B), wherein the metal hydrate (B) comprises (i) the metal When the hydrate (B) is 50 parts by weight or more and less than 100 parts by weight,
(A) 50 parts by weight or more of a metal hydrate pretreated with a crosslinkable silane coupling agent with respect to 100 parts by weight of a thermoplastic resin containing a peroxide crosslinkable thermoplastic polyolefin resin; (ii) When the metal hydrate (B) is 10
In the case of 0 parts by weight or more and 300 parts by weight or less, at least half of the metal hydrate (B) is a mixture having a composition in which the metal hydrate is pretreated with a crosslinkable silane coupling agent. a) A flame-retardant resin composition characterized by being heated and kneaded at a temperature not lower than the melting temperature of a thermoplastic resin containing a peroxide-crosslinked thermoplastic polyolefin resin. 2. The flame-retardant resin composition according to claim 1,
From the group consisting of polyethylene resin, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer and ethylene methacrylate copolymer, a peroxide-crosslinked thermoplastic polyolefin resin synthesized using a single-site catalyst The flame-retardant resin composition according to claim 1, wherein at least one selected from the group is an essential component. 3. The flame-retardant resin composition according to claim 1, wherein the thermoplastic resin contains 60% by weight or less of rubber. 4. The flame-retardant resin composition according to claim 1, wherein the thermoplastic resin comprises (a) a peroxide-crosslinked thermoplastic polyolefin resin, and (c) Heating all of the organic peroxide, (d) the (meth) acrylate-based and / or allylic crosslinking aid, and the metal hydrate (B) above the melting temperature of (a).
A method for producing a flame-retardant resin composition, comprising kneading and crosslinking. 5. The flame-retardant resin composition according to claim 1, wherein the thermoplastic resin comprises (a) a peroxide-crosslinked thermoplastic polyolefin resin as a first step. After heating and kneading the resin composition, as a second step, the kneaded product of the first step, (c) an organic peroxide, (d) a (meth) acrylate and / or allylic crosslinking aid, and metal hydration A method for producing a flame-retardant resin composition, which comprises heating and kneading all of the product (B) at a temperature equal to or higher than the melting temperature of (a) and subjecting it to a crosslinking treatment. 6. The flame-retardant resin composition according to claim 1, wherein (a) a thermoplastic resin composition containing a peroxide-crosslinked thermoplastic polyolefin resin, c) part of the organic peroxide, (d)
After heating and kneading a part of the (meth) acrylate-based and / or allylic cross-linking assistant at the melting temperature of (a) or more and performing a cross-linking treatment (referred to as a thermoplastic resin composition (A)),
(C) The residue of the organic peroxide, (d) the residue of the (meth) acrylate and / or allylic crosslinking aid and all of the metal hydrate (B) are reheated above the melting temperature of (a). A method for producing a flame-retardant resin composition, comprising kneading and crosslinking. 7. The flame-retardant resin obtained by heating and kneading the flame-retardant thermoplastic resin according to claim 1 at a temperature not lower than the melting temperature of (a), and / or after performing a crosslinking treatment. A molded article having the composition as a coating layer on the outside of a conductor or an optical fiber or / and a core of an optical fiber. 8. A flame-retardant resin obtained by heating and kneading the flame-retardant thermoplastic resin according to any one of claims 1 to 3 at a temperature equal to or higher than the melting temperature of (a), and / or after performing a crosslinking treatment. A molded part obtained by molding a composition.