JP4694825B2 - Flame retardant resin composition and molded parts using the same - Google Patents

Description

The present invention provides a flame retardant resin composition having excellent mechanical properties and flexibility, heat resistance, external resistance, pressure contact processability and excellent flame retardancy without requiring crosslinking equipment during processing, and the composition. The present invention relates to a wiring material having an object as a covering material, an optical fiber cord and other molded parts.
More specifically, the present invention relates to an insulated wire, an electric cable, an electric cord, an optical fiber core, an optical fiber cord or the like used for an internal or external wiring of an electric / electronic device, or a mold such as a power cord. With regard to flame retardant resin compositions suitable as materials, tubes and sheets, and wiring materials and other molded parts using them, heat resistance, flexibility, and trauma resistance without the need for special equipment such as crosslinking equipment after processing The present invention relates to a flame retardant resin composition excellent in press-workability and a wiring material and other molded parts using the same.

Insulated wires / cables / cords, optical fiber cores, optical fiber cords, etc. used for internal and external wiring of electrical / electronic equipment are flame retardant, heat resistant, mechanical properties (eg tensile properties, wear resistance) ) And other characteristics are required.
For this reason, as the coating material used for these wiring materials, polyvinyl chloride (PVC) compound and polyolefin compound containing halogen flame retardant containing bromine atom or chlorine atom in the molecule are mainly used. It was.
However, if these are disposed of without appropriate treatment and landfilled, plasticizers and heavy metal stabilizers blended in the coating material are eluted, and appropriate combustion and exhaust treatment conditions are set. In the case of burning without toxic gas, harmful gas may be generated from the halogen compound contained in the coating material or discharged to the outside, and this problem has been discussed in recent years.
For this reason, wiring materials coated with non-halogen flame retardant materials that are free from the risk of elution of harmful plasticizers and heavy metals, which are concerned about having an impact on the environment, and the generation of halogen-based gases are being studied. .

In recent years, insulated wires that use thermoplastic elastomers based on styrenic block copolymers have been used as non-halogen materials with moderate flexibility and a balance between flame retardancy and heat resistance. (For example, patent document 1).
For electric wires used for office automation equipment, audio equipment, personal computers, etc., press contact workability that can process a plurality of electric wires at once is required. When pressure welding is performed, the electric wire is fixed with a plastic strain relief. In this case, when the metal terminal is pressed with the metal terminal, the coating layer of the electric wire in the portion where the metal terminal is in contact It is necessary to break only cleanly and not to expose the conductor due to excessive tearing when the coating layer contacts the press contact blade. Moreover, when fixing to a strain relief part, if the coating layer of an electric wire collapses, fixing will become inadequate. Furthermore, the coating layer is required to have high hardness and tension of the electric wire from the viewpoint of horizontal retention when the electric wire is passed.

However, in an insulated wire using a thermoplastic elastomer based on a conventional styrenic block copolymer, the coating of the portion in contact with the press contact blade at the time of press contact is torn and the conductor is exposed, so the press workability is remarkably inferior. There was a case.
In addition, if the electric wire using the thermoplastic elastomer and the fixing member are in contact with each other for a long time, the softening agent for rubber contained in the covering of the electric wire may move to the fixing member, which may promote deterioration. It was. However, when an electric wire using a thermoplastic elastomer was manufactured without using a softening agent in order to prevent migration of the softening agent, the extrusion load increased and it was difficult to manufacture the electric wire.

JP 2001-316537 A

  The present invention solves the above-mentioned problems, has excellent pressure workability, has high flame retardancy, heat distortion, mechanical properties, and elution of heavy metal compounds at the time of disposal such as landfill and combustion, An object of the present invention is to provide a flame-retardant resin composition and a molded article that are free from the generation of a large amount of smoke and harmful gas and that are compatible with recent environmental problems. Furthermore, the present invention can be reused because the coating material can be remelted while satisfying these characteristics, does not whiten even when bent, is not easily damaged, generates volatile substances at high temperatures for a long period of time, and There is no need for blending of softeners, especially flame retardant resin compositions that have both high flame retardancy and flexibility, and wiring materials, optical fiber cores, optical fiber cords, and other molded parts that use them. It is intended to provide.

  The inventors of the present invention, together with an aromatic vinyl-based thermoplastic elastomer composition containing a hydrogenated product of a random copolymer mainly composed of an aromatic vinyl compound and a conjugated diene compound, the amount of organic peroxide to be used, and a crosslinking aid By appropriately selecting the amount and type of the silane-treated metal hydrate, the resin composition can have a loose cross-linked structure with a low cross-linking density, and a resin composition excellent in pressure workability can be obtained. Furthermore, it has been found that this resin composition has high flame retardancy, heat resistance and mechanical properties and can be re-extruded after molding. The present invention has been completed based on this finding.

That is, the present invention
(1) (b) 5 to 95% by mass of a hydrogenated random copolymer mainly comprising an aromatic vinyl compound and a conjugated diene compound, and (c) 5 to 95% by mass of a polypropylene resin, and if necessary ( a1) ethylene-α-olefin copolymer, (a2) ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer, (a3) ethylene -From 90 mass% or less of at least 1 or more types of resin chosen from (a1)-(a3) of propylene copolymer rubber, and (d) unsaturated carboxylic acid or its derivative (s) and (meth) acrylic acid or its derivative (s) With respect to 100 parts by mass of the thermoplastic resin component (A) containing 70% by mass or less of a resin modified with at least one selected from the group consisting of (e) an organic peroxide 0.001 to 1 part by mass of id, (f) (meth) acrylate-based and / or allylic crosslinking aid 0.003 to 2.5 parts by mass, and metal hydrate (B) 50 to 300 parts by mass And the metal hydrate (B) is
(I) When the metal hydrate (B) is 50 parts by mass or more and less than 100 parts by mass, the metal hydrate pretreated with a silane coupling agent with respect to 100 parts by mass of the thermoplastic resin component (A) 25 parts by mass or more of the product;
(Ii) When the metal hydrate (B) is 100 parts by mass or more and 300 parts by mass or less, at least 1/4 of the metal hydrate (B) is pre-treated with a silane coupling agent. A flame retardant resin composition, which is a mixture of a composition, which is heated and kneaded at a temperature equal to or higher than the melting temperature of the thermoplastic resin component (A) and partially crosslinked in the presence of an organic peroxide. object,
(2) The hydrogenated product of (a) random copolymer described in (1), wherein the number of moles of the linear α-olefin unit structure generated by hydrogenation is ½ or more of the number of moles of the ethylene unit structure. A thermoplastic resin composition,
(3) The crosslinking aid (f) has the general formula

(Here, R is H or CH ₃ , and n is an integer of 1 to 9.)
The flame retardant resin composition according to any one of (1) and (2), wherein the flame retardant resin composition is a (meth) acrylate-based crosslinking aid represented by:
(4) The flame retardant resin composition according to any one of (1) to (3), wherein the metal hydrate (B) is magnesium hydroxide,
(5) The silane coupling agent is a silane compound having any one of the group consisting of a vinyl group, a (meth) acryloyl group, an amino group, and an epoxy group at the terminal. ) Any one of the flame retardant resin compositions,

(6) The flame-retardant resin composition according to any one of (1) to (5) is provided as a coating layer on the outside of a conductor or an optical fiber and / or an optical fiber. Molded articles,
(7) A molded part formed by molding the flame-retardant resin composition according to any one of (1) to (5),
(8) A flame-retardant resin composition for wiring materials for pressure welding, comprising the flame-retardant resin composition according to any one of (1) to (5),
( 9 ) In the flame-retardant resin composition according to any one of (1) to (5), (a1) an ethylene-α-olefin copolymer, (a2) an ethylene-vinyl acetate copolymer, ethylene -(Meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer, (a3) at least one selected from (a1) to (a3) in ethylene-propylene copolymer rubber Resin, (b) hydrogenated random copolymer mainly composed of aromatic vinyl compound and conjugated diene compound, (c) polypropylene resin, (d) unsaturated carboxylic acid or derivative thereof, and (meth) acrylic acid or its A resin modified with at least one selected from the group consisting of derivatives, (e) organic peroxides, (f) (meth) acrylate-based and / or allylic crosslinking aids, A method for producing a flame retardant resin composition, wherein the metal hydrate (B) is simultaneously heated and kneaded at a temperature equal to or higher than the melting temperature of the resin components (a) to (d), and partially crosslinked. And ( 10 ) In the flame-retardant resin composition according to any one of (1) to (5), as a first step, (b) a random copolymer mainly comprising an aromatic vinyl compound and a conjugated diene compound Hydrogenated product, (c) polypropylene resin, (a1) ethylene-α-olefin copolymer, (a2) ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) An acrylic ester copolymer, (a3) at least one resin selected from (a1) to (a3) in an ethylene-propylene copolymer rubber, and (d) an unsaturated carboxylic acid or a derivative thereof and (meta ) After heating and kneading a resin modified with at least one selected from the group consisting of acrylic acid or derivatives thereof to obtain a thermoplastic resin component (A), in the second step, the resin components (A) and (e) The organic peroxide, (f) (meth) acrylate-based and / or allylic crosslinking aid, and metal hydrate (B) are heated and kneaded at a temperature equal to or higher than the melting temperature of the thermoplastic resin component (A), The present invention provides a method for producing a flame-retardant resin composition, which is subjected to a crosslinking treatment.

The flame-retardant resin composition of the present invention is composed of a non-halogen flame-retardant material and does not contain phosphorus, and does not require a crosslinking facility during processing, and has mechanical characteristics, flexibility, and scratch resistance. In addition to being excellent in heat resistance and pressure workability, it has excellent flame retardancy, and when it is disposed of in landfills and combustion, it elutes harmful heavy metal compounds, a large amount of smoke, and harmful gases (corrosive gases) There is no occurrence.
Moreover, the wiring material which is the molded article of the present invention can be produced without using a softening agent, and is excellent in mechanical properties, flame retardancy and heat resistance, and in flexibility.
Further, since the coating layer of the wiring material of the present invention is a partially cross-linked product without tearing the portion that is in contact with the press contact blade at the time of press contact, it is a remeltable material as a coating material. Compared with a wiring material covered with a cross-linked product, it is possible to provide a wiring material rich in recyclability.
From the above, the wiring material of the present invention is very useful as a wiring material for electric / electronic devices in consideration of environmental problems, such as a power cable.
In addition, the flame retardant resin composition of the present invention is used as a coating material for such wiring materials, optical fiber cores, optical fiber cords, etc., and as a material for molded parts, such as power plugs, connectors, tubes and tapes. It is also suitable as a substrate.

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 The thermoplastic resin component (A) contains (b) a hydrogenated random copolymer mainly composed of an aromatic vinyl compound and a conjugated diene compound, and (c) a polypropylene resin. Further, as required, (a1) ethylene-α-olefin copolymer, (a2) ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer And (a3) one or more resins selected from (a1) to (a3) of ethylene-propylene copolymer rubber, and (d) an unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof It may contain a resin modified with at least one selected from the group consisting of

(A1) Component Ethylene-α-Olefin Copolymer As the component (a1) of the present invention, an ethylene-α-olefin copolymer is used.
The ethylene-α-olefin copolymer (a1) is preferably a copolymer of ethylene and an α-olefin having 4 to 12 carbon atoms. Specific examples of the α-olefin include 1-butene, 1- Examples include hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and 1-dodecene.
Examples of the ethylene-α-olefin copolymer in the present invention include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), very low density polyethylene (VLDPE), ethylene-butadiene rubber (EBR), and metallocene catalyst. And an ethylene-α-olefin copolymer polymerized in the presence of. Among these, an ethylene-α-olefin copolymer polymerized in the presence of a metallocene catalyst is preferable. As the production method, known methods described in JP-A-6-306121, JP-A-7-500622 and the like can be used.

A metallocene catalyst has a single polymerization active site and has a high polymerization activity, and is also referred to as a Kaminsky catalyst. An ethylene-α-olefin copolymer synthesized using this catalyst has a molecular weight. The distribution and composition distribution are narrow.
Since the ethylene-α-olefin copolymer polymerized in the presence of such a metallocene-based catalyst has high tensile strength, tear strength, impact strength, etc., it is a non-halogen difficult to high-fill metal hydrate. When used as a fuel material (wiring material coating material), there is an advantage that the deterioration of mechanical properties due to highly filled metal hydrate can be reduced.
On the other hand, when an ethylene-α-olefin copolymer polymerized using a metallocene-based catalyst is used, an increase in melt viscosity or a decrease in melt tension occurs compared to the case of using a normal ethylene-α-olefin copolymer. This causes a problem in moldability. In this regard, two chains are introduced into the molecular weight distribution by introducing long chain branching using asymmetric ligands as metallocene catalysts (Constrained Geometry Catalytic Technology), or by connecting two polymerization vessels during polymerization. Some have improved molding processability by making (Advanced PerformanceTerpolymer).

The density of the ethylene -α- olefin copolymer (a1) of the present invention is preferably 925 kg / ^{m 3} or less, more preferably 915 kg / ^{m 3} or less, particularly preferably 905 kg / ^{m 3} or less. This is because when the density is high, it becomes difficult to fill the metal hydrate with a high degree, resulting in a problem that the flexibility of the resin composition and the wiring material covering the resin composition is lowered. There is no particular limitation on the lower limit of the density.
The ethylene-α-olefin copolymer (a1) preferably has a melt flow rate (hereinafter referred to as MFR) (based on ASTM D-1238) of 0.5 to 30 g / 10 min.

  Examples of the ethylene-α-olefin copolymer (a1) polymerized in the presence of the metallocene catalyst used in the present invention include “AFFINITY” and “ENGAGE” (trade names) from Dow Chemical Co., Ltd. from Nippon Polychem Co., Ltd. "Kernel" (trade name) is marketed by Sumitomo Mitsui Polyolefin Co., Ltd.

(A2) Component Ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer As component (a2) of the present invention, ethylene-vinyl acetate copolymer Polymer, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer (for example, ethylene-butyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate) Copolymer, ethylene-methyl methacrylate copolymer, etc.). Among these, in order to further improve the flame retardancy, it is preferable to use an ethylene-vinyl acetate copolymer.
Furthermore, in order to improve flame retardancy, the content of copolymerization components other than ethylene is preferably 23% by mass or more, more preferably 25% by mass or more, and further preferably 28% by mass or more. For example, in the case of an ethylene-vinyl acetate copolymer, a vinyl acetate (VA) component content of 23% by mass or more is preferable. Further, the MFR is preferably 0.1 g / 10 min or more from the viewpoint of fluidity and 30 g / 10 min or less from the viewpoint of strength retention.

Component (a3) Ethylene-propylene copolymer rubber The ethylene-propylene copolymer rubber (EPM) used for the base resin in the flame-retardant thermoplastic resin composition of the present invention is a rubber-like copolymer of ethylene and propylene. It is. Here, the ethylene-propylene copolymer rubber is one having an ethylene component content of usually about 85 to 40% by mass. There is an ethylene-propylene terpolymer (EPDM) in which a repeating unit having an unsaturated group is added to a polymer as a third component other than ethylene and propylene, but in the present invention, it is necessary to use an EPM having no double bond. . This is because when EPDM is used, the excellent flexibility and elongation, which are the objects of the present invention, are impaired. EPM may be used alone or in combination of two or more.

The ethylene component content in the ethylene-propylene copolymer rubber is suitably 85 to 40% by mass. Preferably it is 80-45 mass%, More preferably, it is 75-50 mass%. If the ethylene component content is too small, the resulting resin composition is insufficiently flexible, and if it is too much, the mechanical strength is lowered.
The Mooney viscosity, ML _{1 + 4} (100 ° C.) of the ethylene-propylene copolymer rubber is preferably 10 to 120, more preferably 40 to 100. When the Mooney viscosity is less than 10, the rubber elasticity of the resulting elastomer composition may be inferior. Moreover, when a product exceeding 120 is used, the moldability may be deteriorated, and the appearance of the molded product is deteriorated.
The weight average molecular weight of the ethylene-propylene copolymer rubber used is preferably 50,000 to 1,000,000, and more preferably 70,000 to 500,000. When the mass average molecular weight is less than 50,000, the resulting composition may be inferior in rubber elasticity. Further, if a material having a mass average molecular weight exceeding 1,000,000 is used, the molding processability is deteriorated and the appearance of the molded product may be deteriorated.

0-50 mass% is preferable in a thermoplastic resin component (A), and, as for the compounding quantity of ethylene-propylene copolymer rubber, More preferably, it is 5-35 mass%. Moreover, when this is too much, the mechanical strength will be reduced.
In the thermoplastic resin component (A) of the present invention, the components (a1) to (a3) are not necessarily essential but are preferably contained. The total of the components (a1) to (a3) is 0 to 90% by mass in 100% by mass of the resin component, preferably 10 to 86% by mass, and more preferably 20 to 83% by mass. When the components (a1) to (a3) are contained, at least one of the components (a1) to (a3) is used, and each may be used alone or a mixture thereof may be used.

(B) Component Hydrogenated Random Copolymer Containing Mainly Aromatic Vinyl Compound and Conjugated Diene Compound The component (b) of the present invention is a copolymer mainly composed of a random structure of a conjugated diene compound and an aromatic vinyl compound. The hydrogenated polymer is an aromatic vinyl compound such as styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl. There are -p-aminoethylstyrene, vinyltoluene, p-tert-butylstyrene and the like, and one or more are selected, and among them, styrene is preferable.
Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethyl-1,3-butadiene, and one or more are selected. Of these, butadiene is preferable.
Moreover, what hydrogenated at least 90% of the aliphatic double bond based on a conjugated diene compound is preferable.

In the component (b), two types of unit structures, that is, an ethylene unit structure and a linear α-olefin unit structure are mainly formed by hydrogenation from a site based on the conjugated diene compound. In the present invention, the straight chain of the linear α-olefin unit structure is preferably long. For example, a 1-butene unit, 1-hexene unit, and 1-octene unit are preferable to a propylene unit. Further, the number of moles of the linear α-olefin unit structure is preferably ½ or more of the number of moles of ethylene unit structure, more preferably 1 or more times, and most preferably 2 or more times.
This is because the miscibility with the resin mixed with the component (b) increases as the straight chain of the linear α-olefin unit structure becomes longer, and the press workability is improved. In addition, the larger the number of moles of the linear α-olefin unit structure relative to the number of moles of ethylene unit structure, the better the miscibility with crystalline polypropylene, and the excellent effects of pressure workability, mechanical properties, and heat deformability. have.

The content of the aromatic vinyl compound is preferably 25% by mass or less, more preferably 20% by mass or less in the component (b). If this amount is too large, the flexibility decreases.
The number average molecular weight of the component (b) is preferably about 5,000 to 1,000,000, more preferably 10,000 to 800,000, and the polydispersity (Mw / Mn) value is 10 or less. Is preferred. Further, the melt flow rate at 230 ° C. and a load of 21.18 N according to ASTM D1238 is preferably 12 g / 10 min or less, more preferably 6 g / 10 min or less.
As the component (b), for example, Dynalon 1320P (trade name) is sold by JSR Corporation.

When the component (b) is used for pressure welding, deformation of the strain relief portion can be significantly suppressed, and cracking of the coating on the pressure welding blade can be greatly reduced. Moreover, when used for a cord, a good appearance can be obtained while maintaining flexibility and terminal processability. Furthermore, since it can be produced without using a rubber softener, there is no concern about the transfer of the softener from the product to another member.
In this invention, the compounding quantity of (b) component is 5-95 mass% in a thermoplastic resin component (A), Preferably it is 6-85 mass%, More preferably, it is 7-75 mass%.

Component (c) Polypropylene resin The polypropylene resin that can be used in the present invention includes homopolypropylene, propylene-ethylene random copolymer, propylene-ethylene block copolymer, propylene and other small amounts of α-olefin (for example, 1 -Butene, 1-hexene, 4-methyl-1-pentene, etc.).
Here, the propylene-ethylene random copolymer refers to a propylene-based crystalline random copolymer, and the propylene-ethylene block copolymer refers to a crystalline polypropylene component (homopolypropylene, propylene-ethylene random copolymer, A copolymer of propylene and a small amount of other α-olefin) and a copolymer rubber component of ethylene and propylene and / or α-olefin.

In this invention, the compounding quantity of the polypropylene resin of (c) component is 5-95 mass% in a thermoplastic resin component (A), Preferably it is 8-90 mass%, More preferably, it is 10-80 mass%. is there.
When the thermoplastic resin component (A) is heat-kneaded and produced as a partially crosslinked product in the present invention, a part of the polypropylene resin as the component (c) can be blended after heat-kneading.
The polypropylene resin blended as the resin component (A) before heating and kneading is thermally decomposed by the presence of the organic peroxide as the component (e) and moderately reduced in molecular weight by subsequent heating and kneading.
As a polypropylene resin mix | blended before heat-kneading, MFR (ASTM-D-1238, L conditions, 230 degreeC) becomes like this. Preferably it is 0.1-50 g / 10min, More preferably, it is 0.2-30 g / 10min. Preferably, 0.3 to 20 g / 10 min is used. If the MFR of the polypropylene resin is less than 0.1 g / 10 minutes, the molecular weight of the polypropylene resin does not decrease even after the heat treatment, and the moldability of the resulting resin composition may be deteriorated, while the MFR is 50 g / 10 minutes. If it exceeds, the molecular weight becomes too low and the rubber elasticity of the resulting resin composition may deteriorate.
The polypropylene resin to be blended after heating and kneading may be any one that matches the extrusion conditions for forming the coating layer, and the MFR is preferably 1 to 200 g / 10 minutes, more preferably 5 to 150 g / 10 minutes. More preferably, 8 to 100 g / 10 min is used. When blended after heating and kneading, if the MFR of the polypropylene resin is less than 1 g / 10 min, the moldability of the resulting resin composition may be deteriorated. If the MFR exceeds 200 g / 10 min, the resin composition obtained Rubber elasticity may deteriorate.

Component (d) Resin modified with at least one selected from the group consisting of unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof. Unsaturated carboxylic acid or derivative thereof which is component (d) of the present invention and ( Examples of the resin modified with at least one selected from the group consisting of (meth) acrylic acid or derivatives thereof include polyethylene (linear polyethylene, ultra-low density polyethylene, high density polyethylene), polypropylene (homopolypropylene, propylene-ethylene random copolymer). Polyolefin resins such as polymers, propylene-ethylene block copolymers, and copolymers of propylene and other small amounts of α-olefins (for example, copolymers of 1-butene, 1-hexene, 4-methyl-1-pentene, etc.) Or a styrene copolymer (for example, styrene-ethylene) -Butene-butylene copolymer (SEBS), styrene-ethylene-propylene-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene-butadiene-butene-styrene copolymer Examples thereof include hydrogenated copolymers such as polymers (SBBS) and non-hydrogenated copolymers such as styrene-butadiene-styrene copolymers (SBS) and styrene-isoprene-styrene copolymers (SIS). Among them, a hydrogenated copolymer is preferable. In the present invention, the component (d) contains these resins as unsaturated carboxylic acids and derivatives thereof (hereinafter collectively referred to as unsaturated carboxylic acids) and (meth) acrylic acid or derivatives thereof (hereinafter referred to as these together). (Meth) acrylic acid or the like). Examples of the unsaturated carboxylic acid used for modification include maleic acid, itaconic acid, fumaric acid and the like, and examples of the unsaturated carboxylic acid derivative include maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid. Examples include monoesters, itaconic acid diesters, itaconic anhydride, fumaric acid monoesters, fumaric acid diesters, and fumaric anhydride. Examples of (meth) acrylic acid used for modification include acrylic acid and methacrylic acid, and examples of (meth) acrylic acid derivatives include acrylic acid esters and methacrylic acid esters.
The modification of the resin can be performed, for example, by heating and kneading at least one of the resin and unsaturated carboxylic acid or the like (meth) acrylic acid in the presence of the organic peroxide. The amount of modification with maleic acid or (meth) acrylic acid is usually about 0.1 to 7% by mass.

By adding a resin modified with at least one selected from the group consisting of this unsaturated carboxylic acid or its derivative and (meth) acrylic acid or its derivative, the effect of increasing the elongation of the resulting resin composition and maintaining the strength In addition, the volume resistivity can be kept high. This resin modified with at least one selected from the group consisting of unsaturated carboxylic acid or its derivative and (meth) acrylic acid or its derivative is effective in alleviating the deterioration of mechanical properties due to metal hydrate and whitening of electric wires There is also an effect to prevent.
Although the resin modified with at least one selected from the group consisting of the unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof as the component (d) of the present invention is not necessarily an essential component, In order to add, it is preferable to add. (D) The compounding quantity of a component is 0-70 mass% in a thermoplastic resin component (A). If the blending amount of component (d) is too large, the extrusion characteristics of the wire may be significantly reduced. In the case of propylene-based modified resins, the extrusion characteristics are unlikely to deteriorate, but in the case of ethylene-based modified resins, the extrusion characteristics are likely to decrease. Therefore, in the case of ethylene-based modified resins, 0 to 30% by mass is more preferable. When using the ethylene-propylene copolymer rubber as the component (a3), the extrusion characteristics are very likely to be deteriorated. Therefore, the blending amount of the component (d) is more preferably 0 to 15% by mass in (A). .

(E) Component 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- (tert-butyl peroxide). Oxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylper) Oxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy Isopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and the like tert- butyl cumyl peroxide.
Of these, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di- in terms of odor, colorability, and scorch stability. (Tert-Butylperoxy) hexyne-3 is most preferred.
The compounding quantity of organic peroxide (e) is the range of 0.001-1.0 mass part with respect to 100 mass parts of thermoplastic resin components (A), Preferably 0.01-0.5 mass part It is. By selecting the organic peroxide within this range, the crosslinking does not proceed excessively, so that a partially crosslinked composition excellent in extrudability can be obtained without generating scum.

(F) Component (Meth) acrylate-based and / or allyl-based crosslinking aid In the production of the flame-retardant resin composition of the present invention or the thermoplastic resin component (A) used therein, crosslinking aid is present in the presence of an organic peroxide. A partially crosslinked structure is formed between the aromatic vinyl-based thermoplastic elastomer and the ethylene-α-olefin copolymer via the agent. As the crosslinking aid used at that time, the general formula

(Here, R is H or CH ₃ , and n is an integer of 1 to 9.)
The (meth) acrylate type crosslinking adjuvant represented by these is mentioned.
Here, the (meth) acrylate-based crosslinking aid refers to an acrylate-based and methacrylate-based crosslinking aid. 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 these, a (meth) acrylate-based crosslinking assistant having n of 1 to 6 is 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 dispersion aid for peroxide. The cross-linking effect at the time of kneading is most preferable because it provides a uniform and effective cross-linking thermoplastic resin having a balance between hardness and rubber elasticity. By using such a compound, it is possible to expect a uniform and efficient partial crosslinking reaction at the time of heating and kneading without being insufficiently crosslinked or excessively crosslinked.

  The addition amount of the crosslinking aid used in the present invention is preferably in the range of 0.003 to 2.5 parts by mass, more preferably 0.05 to 1.100 parts by mass with respect to 100 parts by mass of the thermoplastic resin component (A). 6 parts by mass. By selecting the crosslinking aid within this range, a partially crosslinked structure having a low crosslinking density is obtained without excessive crosslinking, and a composition excellent in extrudability is obtained without generation of blisters. The blending amount of the crosslinking aid is preferably about 1.5 to 4.0 times the addition amount of the organic peroxide by mass ratio.

By adding the peroxide of the component (e) and the crosslinking aid of the component (f), partial crosslinking occurs at the time of kneading, and the heat resistance equivalent to PVC can be maintained. Furthermore, by producing a direct bond between the component (a) and the component (b) and a bond via the crosslinkable silane coupling agent of the component (B), high strength and trauma resistance are obtained. The terminal processability can be maintained. In particular, the addition of the component (b) to the cross-linking component provides an appearance similar to that of PVC. For example, in the case of a cord, it is excellent in ending processability, and in the case of a pressure welding wire, deformation of the strain relief portion is minimized. It becomes possible to suppress to. Furthermore, by introducing the component (b), it is possible to have the same slipperiness as that of the PVC electric wire, and even an automatic processing machine can be processed by a processing prescription equivalent to PVC.

(B) Metal Hydrate The metal hydrate used in the present invention is not particularly limited. For example, aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, A compound having a hydroxyl group or crystal water such as hydrotalcite can be used alone or in combination of two or more. Of these metal hydrates, aluminum hydroxide and magnesium hydroxide are preferred. Metal hydrate must be at least partially treated with a silane coupling agent, but is not surface-treated untreated metal hydrate or metal water treated with other surface treatment agents such as fatty acids A Japanese thing can be used together suitably.

Examples of the silane coupling agent used for the surface treatment of the metal hydrate include vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, and glycidoxypropylmethyl. Silane coupling agents having vinyl groups such as dimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane and methacryloxypropylmethyldimethoxysilane, (meth) acryloyl groups or epoxy groups, mercaptopropyltrimethoxysilane , A silane coupling agent having a terminal mercapto group such as mercaptopropyltriethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, N- (β-a Noethyl) -γ-aminopropyltripropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltripropylmethyldimethoxysilane and other silane coupling agents having an amino group, etc. Is preferred. Two or more of these silane coupling agents may be used in combination.
Among such silane coupling agents, silane coupling agents having an epoxy group and / or vinyl group, (meth) acryloyl group, and amino group at the terminal are preferable, and an epoxy group and / or vinyl group at the terminal (meta) ) Those having an acroyl group are preferred. These may be used alone or in combination of two or more.

As the silane coupling agent surface-treated magnesium hydroxide that can be used in the present invention, non-surface-treated magnesium hydroxide (commercially available products such as “Kisuma 5” (trade name, manufactured by Kyowa Chemical Industry Co., Ltd.)), stearin Surface treated with fatty acids such as acid and oleic acid ("Kisuma 5A" (trade name, manufactured by Kyowa Chemical Industry Co., Ltd.), etc., and those treated with phosphate ester using the above silane coupling agent There is what I did. In addition, commercial products of magnesium hydroxide already surface-treated with a silane coupling agent ("Kisuma 5L", "Kisuma 5P" (both trade names, manufactured by Kyowa Chemical Industry Co., Ltd.), "Fine Mag MO-E" (Trade name, manufactured by TMG Co., Ltd.).
In addition to the above, a silane coupling having a functional group such as a vinyl group or an epoxy group at its terminal in addition to magnesium hydroxide or aluminum hydroxide whose surface is partially pretreated with a fatty acid or a phosphate ester. It is also possible to use a metal hydrate that has been surface-treated with an agent.

  When treating a metal hydrate with a silane coupling agent, it is necessary to blend the silane coupling agent with the metal hydrate in advance. At this time, the silane coupling agent is appropriately added in an amount sufficient for the surface treatment, and specifically, 0.2 to 2% by mass with respect to the metal hydrate is preferable. The silane coupling agent may be a stock solution or may be diluted with a solvent.

The compounding quantity of a metal hydrate is 50-300 mass parts with respect to 100 mass parts of thermoplastic resin components (A) in the resin composition of this invention.
In the present invention, when (i) the metal hydrate is 50 parts by mass or more and less than 100 parts by mass, 25 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin component (A), and (ii) metal water When the sum is 100 parts by mass or more, it is possible to obtain a material excellent in flexibility while maintaining high strength by making a metal hydrate pretreated with at least 1/4 of the silane coupling agent. It becomes possible.
Furthermore, the metal hydrate is 50 to 300 parts by mass with respect to 100 parts by mass of the thermoplastic resin component (A), but (i) when the metal hydrate is 50 parts by mass or more and less than 100 parts by mass, 25 parts by mass or more with respect to 100 parts by mass of the plastic resin component (A), and (ii) when the metal hydrate is 100 parts by mass or more and 300 parts by mass or less, at least 1/2 of the silane coupling agent In addition, by using the metal hydrate pretreated with, a material and an electric wire excellent in external damage resistance, high strength and excellent in terminal workability can be obtained.

  When polyolefin resin such as normal polyethylene resin or polypropylene resin is used as the base resin and a large amount of metal hydrate is added to satisfy the required flame retardancy, the mechanical strength is greatly reduced. . On the other hand, the thermoplastic resin component (A) in the present invention has a low crosslink density and the resin components are in a partially cross-linked state via the component (b), so that it has excellent filler acceptability, and such thermoplasticity. When the resin component (A) is used as a base resin, a large amount of metal hydrate can be blended. Among them, only when a specific amount of a metal hydrate treated with a silane coupling agent is blended, the base resin of component (A) and the metal hydrate of component (B) interact through the silane coupling agent. Therefore, a decrease in mechanical strength is suppressed to a minimum, and whitening hardly occurs when bent, and satisfactory characteristics can be obtained as a coating material for a wiring material or a molded part.

  The details of the reaction mechanism during heating and kneading of the resin composition of the present invention are not yet clear, but are considered as follows. That is, when the thermoplastic resin component (A) in the present invention is heated and kneaded, in the presence of the organic peroxide as the component (e), (a1) to (a3) through the crosslinking aid as the component (f). ) Component, (b) component, and (d) component are crosslinked. On the other hand, the melt viscosity of the resin composition can be appropriately adjusted by appropriately reducing the molecular weight of the polypropylene resin as the component (c) by the action of the component (e). As a result, the composition as a whole becomes a crosslinked product having excellent extrudability. The crosslinking of the composition of the present invention may be carried out in the presence of a small amount of the component (e), and can be referred to as partial crosslinking because it has fewer crosslinking points than ordinary crosslinking.

When filling the thermoplastic resin component (A) with the metal hydrate (B), a specific amount of the metal hydrate treated with the silane coupling agent is blended simultaneously with the components (e) and (f). Only when it is possible to add a large amount of metal hydrate without impairing the extrusion processability at the time of molding, and while maintaining high flame retardancy and flexibility, it has heat resistance and mechanical properties. In addition, it is possible to obtain a recyclable flame retardant resin composition that can be re-extruded after use.
The details of the mechanism of the action of the metal hydrate treated with the silane coupling agent are not yet clear, but are considered as follows. In other words, the silane coupling agent bonded to the surface of the metal hydrate by treating with the silane coupling agent has one alkoxy group bonded to the metal hydrate and the vinyl or epoxy group present at the other end is removed. Various reactive sites including the first bond to the uncrosslinked portions of the components (a1) to (a3), the component (b), and the component (d). This makes it possible to mix a large amount of metal hydrate without impairing the extrusion moldability, strengthen the adhesion between the resin and the metal hydrate, and have good mechanical strength and wear resistance. A flame-retardant resin composition that is not easily damaged is obtained.

In this invention, a flame retardance can be improved by adding a melamine cyanurate further.
The melamine cyanurate compound used in the present invention preferably has a fine particle size. The average particle size of the melamine cyanurate compound used in the present invention is preferably 10 μm or less, more preferably 7 μm or less, and even more preferably 5 μm or less. Moreover, the melamine cyanurate compound surface-treated from the dispersible surface is used preferably.
Examples of the melamine cyanurate compound that can be used in the present invention include “MCA-0” and “MCA-1” (both trade names, manufactured by Mitsubishi Chemical Corporation) and those marketed by Chemie Linz GmbH. There is. Examples of the melamine cyanurate compound surface-treated with fatty acid and the silane surface-treated melamine cyanurate compound include “MC610” and “MC640” (both trade names, manufactured by Nissan Chemical Industries, Ltd.).
As a melamine cyanurate compound which can be used by this invention, the melamine cyanurate of the following structures can be mentioned, for example.

  In this invention, the compounding quantity of a melamine cyanurate compound is 3-70 mass parts with respect to 100 mass parts of thermoplastic resin components (A), Preferably it is 5-40 mass parts. If the amount of the melamine cyanurate compound is too small, the effect of improving the flame retardancy will not be exhibited. If the amount is too large, the mechanical strength, in particular, the elongation will decrease, and the appearance of the electric wire will deteriorate.

The flame retardant resin composition of the present invention can be blended with at least one selected from the group consisting of zinc borate, zinc stannate and zinc hydroxystannate as necessary, and further improve the flame retardancy. be able to. By using these compounds, the speed of shell formation during combustion is increased and the shell formation becomes stronger. Therefore, together with the melamine cyanurate compound that generates gas from the inside during combustion, the flame retardancy can be dramatically improved, and a high degree of flame retardancy can be imparted.
Zinc borate, zinc stannate, and zinc hydroxystannate used in the present invention preferably have an average particle size of 5 μm or less, more preferably 3 μm or less.
Specific examples of zinc borate that can be used in the present invention include, for example, “Alkanex FRC-500 (2ZnO / 3B ₂ O ₃ .3.5H ₂ O)”, “Alkanex FRC-600” (both Product name, Mizusawa Chemical Co., Ltd.). In addition, as zinc stannate (ZnSnO ₃ ) and hydroxy hydroxystannate (ZnSn (OH) ₆ ), “Alkanex ZS” and “Alkanex ZHS” (both trade names, manufactured by Mizusawa Chemical Co., Ltd.) is there.
In the present invention, the compounding amount of zinc borate, zinc stannate or zinc hydroxystannate is 0.5 to 20 parts by mass, preferably 2 to 15 parts by mass with respect to 100 parts by mass of the thermoplastic resin component (A). . If the amount is too small, the effect of improving the flame retardancy will not be exhibited. If the amount is too large, the mechanical strength, particularly the elongation will be reduced, and the appearance of the electric wire will be deteriorated.

In the flame-retardant resin composition of the present invention, various additives commonly used in electric wires, cables, cords, tubes, electric wire components, sheets, etc., for example, antioxidants, metal deactivators, Flame retardant (auxiliary) agents, fillers, lubricants, and the like can be appropriately blended within a range not impairing the object of the present invention.
Antioxidants include amine-based antioxidants such as 4,4′-dioctyl diphenylamine, N, N′-diphenyl-p-phenylenediamine, and 2,2,4-trimethyl-1,2-dihydroquinoline polymer. 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-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and the like, bis (2-methyl-4- ( 3-n-alkylthiopropionyloxy) -5-tert-butylphenyl) sulfide, 2-mercaptobenzimidazole and its zinc salt, pentaerythris Tall - tetrakis (3-lauryl - thiopropionate) and the like sulfur-based antioxidant such.

Examples of metal deactivators include N, N′-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1,2,4. -Triazole, 2,2'-oxamidobis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like.
In addition, flame retardants (auxiliaries) and fillers include carbon, clay, zinc oxide, tin oxide, titanium oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silicone compounds, quartz, talc, calcium carbonate, magnesium carbonate, white For example, carbon.

In particular, silicone compounds such as silicone rubber and silicone oil not only impart and improve flame retardancy, but also in insulators (coating layers comprising the flame retardant resin composition) and conductors in electric wires and cords. The cable has an effect of reducing the trauma by controlling the adhesion force with the cable and providing the cable with lubricity. Specific examples of the silicone compound used in the present invention include “SFR-100” (trade name, manufactured by GE), “CF-9150” (trade name, manufactured by Toray Dow Silicone Co., Ltd.), and the like. A commercial item is mentioned.
When added, the silicone compound is preferably blended in an amount of 0.5 to 15 parts by mass with respect to 100 parts by mass of the thermoplastic resin component (A). If the amount is less than 0.5 parts by mass, there is practically no effect on flame retardancy and lubricity. If the amount exceeds 15 parts by mass, the appearance of the wire / cord / cable is reduced, and the extrusion speed is reduced, resulting in mass productivity. May get worse.
Examples of the lubricant include hydrocarbons, fatty acids, fatty acid amides, esters, alcohols, and metal soaps.

  In the flame-retardant resin composition of the present invention, the additive and other resins can be introduced as long as the object of the present invention is not impaired, but at least the thermoplastic resin component (A) is a main resin component. To do. Here, the main resin component is usually 70% by mass or more, preferably 85% by mass or more, more preferably the total amount of the resin component in the resin component of the flame-retardant resin composition of the present invention. (A) means to occupy. Here, in the thermoplastic resin component (A), the components (a1) to (a3), (b), (c), and (d) each have a use amount within the specified range, and the thermoplastic resin component ( A) is 100% by mass in the total amount of components (a) to (d).

Next, the manufacturing method of the flame-retardant resin composition of this invention is demonstrated.
Add components (a) to (d), metal hydrate (B), components (e) and (f), and heat knead. The kneading temperature is preferably 160 to 240 ° C. The kneading conditions such as kneading temperature and kneading time are such that the resin components (a) to (d) are melted and the organic peroxide acts to achieve the necessary partial crosslinking. It can be set as appropriate to an extent sufficient. The kneading method can be satisfactorily used as long as it is a method usually used for rubber, plastic and the like. As the apparatus, for example, a single screw extruder, a twin screw extruder, a roll, a Banbury mixer or various kneaders are used. By this step, a flame retardant resin composition in which each component is uniformly dispersed can be obtained.
Of the metal hydrates to be blended, it is important that the metal hydrate treated with the silane coupling agent is previously treated with the silane coupling agent. By using a metal hydrate that has been surface-treated in advance, it becomes possible to formulate a sufficient amount of metal hydrate to ensure flame retardancy, and particularly good mechanical strength and wear resistance. Thus, a flame-retardant resin composition that is hardly damaged is obtained.

As another method, the components (a) to (d) are first heated and kneaded in the first step to obtain the thermoplastic resin component (A). In the second step, the components (e), (f) and the metal hydrate (B) are added to the thermoplastic resin component (A) obtained in the first step, and the mixture is heated and kneaded. The temperature at this time is preferably 160 to 240 ° C. Also in this case, the kneading conditions such as kneading temperature and kneading time are such that the thermoplastic resin component (A) is melted and the contained organic peroxide is partially crosslinked. It can set suitably so that it may fully be used.
In this way, the components (a) to (d) are preliminarily heated and kneaded to be microdispersed, and then the components (e) and (f) and the metal hydrate (B) are added and heated and kneaded. Good. Also in this case, when the surface-treated metal hydrate is used, it is necessary to finish the surface treatment before blending.

The flame retardant resin composition of the present invention is suitable for coating and manufacturing of wiring parts, optical fiber cores, optical fiber cords and the like used for internal and external wiring of electric / electronic devices.
When the flame-retardant resin composition of the present invention is used as a coating material for a wiring material, it preferably comprises at least one layer of the flame-retardant resin composition of the present invention formed on the outer periphery of a conductor by extrusion coating. There is no restriction | limiting in particular except having a coating layer. For example, as the conductor, any one of known ones such as an annealed copper single wire or stranded wire can be used. In addition to the bare wire, the conductor may be tin-plated or an enamel-covered insulating layer.
The wiring material which is the molded article of the present invention is formed by extruding the flame retardant resin composition of the present invention around a conductor or an insulated wire using a general-purpose extrusion coating apparatus although no softener is blended. Can be manufactured. The temperature of the extrusion coating apparatus at this time is preferably about 180 ° C. at the cylinder portion and about 200 ° C. at the crosshead portion. In the present invention, the flame retardant resin composition does not contain a softening agent, but can be easily extrusion-coated.
In the wiring material of the present invention, the thickness of the insulating layer (the 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.

Moreover, in the wiring material of the present invention, it is preferable to form the coating layer as it is by extrusion coating the flame retardant resin composition of the present invention which is a partially crosslinked product, but for the purpose of further improving the heat resistance. It is also possible to crosslink the coating layer after extrusion. However, when this crosslinking treatment is performed, it becomes difficult to reuse the coating layer as an extruded material.
As a method for crosslinking, an electron beam irradiation crosslinking method or a chemical crosslinking method can be employed.
In the case of the electron beam crosslinking method, the flame retardant resin composition of the present invention is extruded to form a coating layer, and then crosslinked by irradiating an electron beam by a conventional method. An electron beam dose of 1 to 30 Mrad is appropriate, and in order to efficiently perform crosslinking, a flame retardant resin composition constituting a coating layer, a methacrylate compound such as trimethylolpropane triacrylate, triallyl cyanurate, etc. Polyfunctional compounds such as allyl compounds, maleimide compounds, and divinyl compounds may be added as a crosslinking aid.
In the case of the chemical crosslinking method, an organic peroxide is blended in the flame retardant resin composition as a crosslinking agent, extruded to form a coating layer, and then crosslinked by heat treatment according to a conventional method.

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 material, a tube, and a sheet. The molded part of the present invention is molded from the flame retardant resin composition of the present invention by a molding method such as ordinary injection molding.
Sheets, tubes, and the like can be extruded in the same manner as the wire coating. Moreover, you may bridge | crosslink by a chemical crosslinking method or an electron beam crosslinking method similarly to an electric wire.
Further, when an injection molded product such as an electric wire part is obtained as the molded part of the present invention, it can be injection molded at a cylinder temperature of about 220 ° C. and a head temperature of about 230 ° C. The injection molding apparatus can be molded by using an injection molding machine used for molding a normal PVC resin or the like.

In the present invention, the optical fiber core or the optical cord is formed by using a general-purpose extrusion coating apparatus, using the flame retardant resin composition of the present invention as a coating layer, around the optical fiber, or having a tensile fiber. Manufactured by extrusion coating around an optical fiber core that is spliced or twisted. The temperature of the extrusion coating apparatus at this time is preferably about 180 ° C. at the cylinder portion and about 200 ° C. at the crosshead portion.
The optical fiber core wire which is the molded article of the present invention may be used as it is without providing a coating layer around it depending on the application.
In addition, the optical fiber core wire or cord of the present invention includes all of the optical fiber strand or the core wire coated on the outer periphery with the flame retardant resin composition of the present invention as a coating layer, and its structure is particularly limited. Not what you want. The thickness of the coating layer and the type and amount of the tensile strength fiber that is vertically attached or twisted to the optical fiber core wire vary depending on the type and use of the optical fiber cord, and can be set as appropriate.

1-3 show an example of the structure of the optical fiber core and cord of the present invention.
FIG. 1 is a cross-sectional view of an embodiment of an optical fiber core according to 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. 2 is a cross-sectional view of an embodiment of an optical fiber cord according to the present invention in which a coating layer 5 is formed on the outer periphery of a single optical fiber core 3 in which a plurality of tensile strength fibers 4 are vertically attached.
FIG. 3 shows an optical fiber cord of the present invention (optical fiber two-core cord) in which a plurality of tensile fibers 4 are vertically attached to the outer circumferences of two optical fiber cores 3 and 3, and a coating layer 6 is formed on the outer circumference. ) Is a cross-sectional view of another embodiment.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.
Examples 1-26, Comparative Examples 1-8 (However, Example 8 is a missing number.)
As the component (a1), ethylene-1-hexene copolymer, as the component (a2), ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, as the component (a3), ethylene-propylene copolymer rubber, Thermoplastic resin component (A) using hydrogenated styrene-butadiene random copolymer as component (b), block polypropylene as component (c), maleic acid-modified polyethylene and acrylic acid-modified polypropylene as component (d) It was.
(E) 2,5-dimethyl-2,5-di (t-butylperoxy) -hexane as the organic peroxide of component, (f) triethylene glycol dimethacrylate as the crosslinking assistant, and component (B) As used, magnesium hydroxide surface-treated with a silane coupling agent or magnesium hydroxide surface-treated with a fatty acid was used.
However, in Comparative Examples 2, 3, and 5, a styrenic block copolymer was blended (in some cases) instead of the hydrogenated random copolymer of component (b). Moreover, paraffin oil was blended.
Each of the above components was blended as shown in Tables 1 to 5 (in parts by mass) to prepare a composition.

In Examples 1 to 10 and 12 to 26 and Comparative Examples 1 to 8, each component (a) to (f) shown in the table and other additives such as antioxidants were dry blended at room temperature, and 200 ° C. Was heated using a Banbury mixer, melted and kneaded, and discharged to obtain a flame retardant resin composition. The discharge temperature was 200 ° C.
In Example 11, the thermoplastic resin component was dry blended at room temperature, melt kneaded at 170 ° C. using a Banbury mixer, and then pelletized. Then, it knead | mixed at 220 degreeC with the biaxial extruder with the organic peroxide, the crosslinking adjuvant, and the metal hydrate, and discharged | emitted, and the flame-retardant resin composition was obtained.
From the obtained resin composition, 1 mm and 3 mm thick sheets corresponding to each Example and Comparative Example were created by pressing, based on specific gravity (3 mm sheet), hardness (3 mm sheet), and JIS K 6723, Tensile properties (maximum stress (MPa), maximum elongation (%), 100% stress (MPa) (1 mm sheet) were measured. Regarding hardness, Examples 1-11 and 24-26 and Comparative Examples 1- For 4 and 8, Shore hardness A, 15 seconds was employed, and for Examples 12-23 and Comparative Examples 5-7, Shore hardness D, 5 seconds were employed.
The measurement results are shown in Tables 1-5.

Next, for Examples 1 to 11 and 24-26 and Comparative Examples 1 to 4 and 8, a conductor (conductor diameter: 0.95 mmφ tin-plated annealed copper stranded wire Configuration: 30 pieces / 0.18 mmφ), and the resin compositions having the compositions shown in Tables 1 and 2 for the insulation coating previously melted are extrusion coated to have an outer diameter of 2.74 mm corresponding to each of the examples and comparative examples. An insulated wire was manufactured.
Moreover, about Examples 12-23 and Comparative Examples 5-7, on the conductor (conductor diameter: 0.95 mmφ tin plated annealed copper stranded wire configuration: 7 / 0.16 mmφ) using an extrusion coating apparatus for electric wire production Next, the resin composition having the composition shown in Table 3 for insulating coating melted in advance was extrusion coated to produce an insulated wire having an outer diameter of 0.98 mm corresponding to each of the examples and comparative examples.

About each obtained insulated wire, about Examples 1-11, 24-26, and Comparative Examples 1-4 and 8, the tensile characteristic (tensile strength, elongation), a flame retardance (horizontal combustion test), the adhesion | attachment with respect to a tape The properties and appearance were evaluated, and the results are shown in Table 1, 2 or 5.
For Examples 12 to 14 and Comparative Examples 5 to 7, the tensile properties (tensile strength, elongation), flame retardancy (vertical combustion test, horizontal combustion test), and the characteristics of the press contact wire (strain relief, press contact blade) are evaluated. The results are also shown in Table 3.
For Examples 15 to 23, the tensile properties (tensile strength, elongation), flame retardancy (vertical combustion test, horizontal combustion test), the characteristics of press-contacted wires (strain relief, press-contact blade), adhesiveness to tape, and appearance The results are shown in Table 4.

Tensile properties were determined by measuring the tensile strength (MPa) and elongation at break (%) of the insulator (coating layer) of each insulated wire under conditions of a gap between marked lines of 25 mm and a tensile speed of 500 mm / min. The elongation is required to be 100% or more, and the strength is required to be 10 MPa or more.
For horizontal combustion, a horizontal combustion test specified in JIS C 3005 was performed for each insulated wire, and the self-extinguishment within 30 seconds was regarded as acceptable, and the non-self-extinguishing within 30 seconds was regarded as unacceptable.
In the vertical combustion, a vertical combustion test defined in UL1581 was performed for each insulated wire, and five were burned and all were passed as “pass”, and even one failed was indicated as “fail”. However, even if it fails in this test, it can be used as a horizontal combustion grade.
Appearance: Visual inspection of the presence or absence of fluctuations in the outer diameter of the insulated wire and the condition of the surface. If these were good, the outer diameter was unstable, the outer diameter was unstable, and the surface was rough. Is indicated by x.
Regarding adhesion to the tape after being left, Scotch Brand Tape made by Sumitomo 3M was attached to the electric wire, and it was confirmed that the tape was easily peeled off after being left at 40 ° C. for 2 weeks. ○ was marked for those that were difficult to peel off at the initial stage and after standing, and x was marked for those that could be easily removed after the initial state or standing.
The pressure contact property was evaluated by using a MOLEX 15-pin MIII connector, processing the wire with a hand press, and observing the pressure contact portion.
Although the strain relief is less than the arrowhead of the relief part but the number of pins is 12 or more (those exceeding the arrowhead is less than 3 pins), the rise of the cover is below the arrowhead of the relief part An electric wire having a number of pins smaller than 12 pins (those exceeding the arrowhead and larger than 3 pins) was marked with x.
As for the pressure contact blade, no crack was generated in the coating at the pressure contact portion, and ○ even one wire was broken.

As each compounding component shown in Tables 1-5, the following were used.
(A) Thermoplastic resin component (a1) Component: ethylene-α-olefin copolymer Type: ethylene-1-hexene copolymer Product name: KF-370
Manufacturing company: Nippon Polychem Corporation Density: 903 kg / m ³ MFR: 3.5 g / 10 min (190 ° C., load 21.18 N)
Type: Ethylene-1-hexene copolymer Product name: KS-240
Manufacturing company: Nippon Polychem Corporation Density: 880 kg / m ³ MFR: 2.2 g / 10 min (190 ° C., load 21.18 N)
Type: Ethylene-hexene copolymer Product name: KF-360
Manufacturing company: Nippon Polyethylene Corporation
Density: 898 kg / m ³ MFR: 3.5 g / 10 min (190 ° C., load 21.18 N)
Component (a2): Ethylene-vinyl acetate copolymer Type: Ethylene-vinyl acetate copolymer Product name: EV-180 Manufacturer: Mitsui DuPont Polychemical Co., Ltd.
VA component content: 33% by mass
MFR: 0.5 g / 10 min (190 ° C., load 21.18 N)
Type: Ethylene-vinyl acetate copolymer Product name: V-527-4 Manufacturer: Mitsui DuPont Polychemical Co., Ltd.
VA component content: 17% by mass
MFR: 0.8 g / 10 min (190 ° C., load 21.18 N)
Type: Ethylene-ethyl acrylate copolymer Product name: A-714 Manufacturer: Mitsui DuPont Polychemical Co., Ltd.
EA component content: 25% by mass
MFR: 0.5 g / 10 min (190 ° C., load 21.18 N)
Type: Ethylene-vinyl acetate copolymer Product name: Ultrasen YX21K Manufacturer: Tosoh Corporation
VA component content: 42% by mass
MFR: 0.4 g / 10 min (190 ° C., load 21.18 N)
(A3) Ethylene-propylene copolymer rubber Type: Ethylene-propylene copolymer rubber Product name: EP07P Manufacturer: JSR Corporation
Ethylene component content: 73% by mass
Mooney viscosity M _{1 + 4} (100 ° C.): 70

(B) Hydrogenated product of random copolymer of aromatic vinyl-conjugated diene Type: Hydrogenated product of styrene-butadiene random copolymer Product name: Dynalon 1320P Manufacturer: JSR Corporation
Styrene component content: 10% by mass,
1-butene unit structure 56.9 mol%, ethylene unit structure 39.0 mol%
Weight average molecular weight: 300,000 Hydrogenation rate: 90% or more, Mw / Mn: 1.1
Molar ratio of ethylene unit structure to α-olefin unit structure: 0.7
MFR: 3.5 g / 10 min (230 ° C., load 21.18 N)
(Comparative example) Hydrogenated block copolymer of aromatic vinyl-conjugated diene Type: Styrene / ethylene / propylene / styrene copolymer (SEPS)
Product name: Septon 4077 Manufacturer: Kuraray Co., Ltd. Styrene component content: 30% by mass, isoprene component content: 70% by mass
Weight average molecular weight: 320,000, Hydrogenation rate: 90% or more (c) Polypropylene resin Type: Block polypropylene Product name: BC8
Manufacturing company: JPO
MFR: 1.8 g / 10 min (230 ° C., 21.18 N), DSC melting point: 162 ° C.
15% by mass of rubber component (soluble component when dissolved in boiling p-xylene and then allowed to cool to room temperature)
Type: Random polypropylene Product name: FW3E
Manufacturing company: Nippon Polypro Co., Ltd.
MFR: 7 g / 10 min (230 ° C., 21.18 N), DSC melting point: 140 ° C.

(D) Resin modified with at least one selected from the group consisting of unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof Type: Maleic acid-modified polyethylene Product name: Admer XE070 Manufacturing company: Mitsui Chemicals, Inc.
Type: Acrylic acid-modified polypropylene Product name: Polypond P1002 Manufacturer: Uniroyal Corporation MFR: 20 g / 10 min (230 ° C., 21.18 N), modification rate: 6% by mass
Type: Maleic acid modified EBR
Product name: Toughmer MH7010 Manufacturer: Mitsui Chemicals, Inc.
Type: Maleic acid-modified styrene / ethylene / butylene / styrene copolymer (SEBS)
Product Name: Clayton M1913
Manufacturer: Kraton Polymer Japan Co., Ltd.
(E) Organic peroxide Type: 2,5-Dimethyl-2,5-di (t-butylperoxy) -hexane Product name: Perhexa 25B Manufacturing company: NOF Corporation
(F) Crosslinking aid Type: Triethylene glycol dimethacrylate Product name: NK ester 3G Manufacturer: Shin-Nakamura Chemical Co. Type: 1,9-nonanediol dimethacrylate and 2-methyl-1,8-octanediol dimethacrylate 15:85 (mass ratio) mixture with the product name: NK ester IND Manufacturing company: Shin-Nakamura Chemical Co., Ltd.

(B) Metal hydrate Type: Magnesium hydroxide surface treated with silane coupling agent Product name: Kisuma 5L Manufacturer: Kyowa Chemical Industry Co., Ltd.
Type: Untreated magnesium hydroxide Product name: Kisuma 5 Manufacturer: Kyowa Chemical Industry Co., Ltd.
Type: Fatty acid-treated magnesium hydroxide Product name: Kisuma 5B Manufacturer: Kyowa Chemical Industry Co., Ltd.

Other thermoplastic resin components Type: Paraffin oil Product name: Diana Process Oil PW-90 Manufacturer: Idemitsu Kosan Co., Ltd.
Type: Silicon concentrate (LDPE / silicone gum = 50/50 (M / M))
Product Name: BY27-022
Manufacturer: Toray Dow Corning Silicone Co., Ltd.
Phenolic antioxidant type: pentaerythrityl-tetrakis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate)
Product Name: Irganox 1010
Manufacturing company: Ciba Specialty Chemicals Co., Ltd.
Light stabilizer Type: Hindered amine Product name: Tinuvin-111FDL
Manufacturing company: Ciba Specialty Chemicals Co., Ltd.
Lubricant Type: Polyethylene wax Product name: AC polyethylene No. 6 Manufacturing company: Hoechst silane coupling agent Type: Silane coupling agent having an amino group at the end Product name: TSL8331 Manufacturing company: GE Toshiba Silicone Type: Silane coupling agent having a methacryloyl group at the end Product name: TSL8370 Company: GE Toshiba Silicone

As can be seen from the table, Comparative Examples 1 and 7 have a metal hydrate content outside the scope of the present invention, and Comparative Examples 2 to 5 contain a hydrogenated random copolymer as component (b). In Comparative Example 6, the compounding amount of the metal hydrate is 250 parts, but the pre-treatment with the silane coupling agent is only 1/5.
Comparative Example 1 has a problem in horizontal combustibility, Comparative Examples 2 to 4 have a problem in adhesion to the tape, and Comparative Examples 6 and 7 do not satisfy the characteristics of the press-contact wire. In Comparative Examples 4, 5, and 7, the breaking elongation of the wire coating layer is small, and Comparative Examples 5 and 7 have a problem in sheet elongation. Further, in Comparative Example 5, a crack occurred at the press contact portion of the electric wire. Moreover, the comparative example 8 does not contain (c) component, and the tensile property after heat processing is inferior.
In contrast, the insulated wires using the flame retardant resin compositions of Examples 1 to 26 were excellent in mechanical properties, flexibility, external resistance, heat resistance, press workability, and flame resistance. .

It is sectional drawing of one Example of the optical fiber core wire of this invention which provided the coating layer directly in the outer periphery of an optical fiber strand. It is sectional drawing of one Example of the optical fiber cord of this invention which formed the coating layer in the outer periphery of the one optical fiber core wire which vertically attached the some tensile strength fiber. FIG. 6 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 circumferences of two optical fiber cores and a coating layer is formed on the outer circumference thereof.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical fiber strand 2 Coating layer 3 Optical fiber core wire 4 Tensile fiber 5 Coating layer 6 Coating layer

Claims (10)

(B) 5 to 95% by mass of a hydrogenated random copolymer mainly composed of an aromatic vinyl compound and a conjugated diene compound, and (c) 5 to 95% by mass of a polypropylene resin, and (a1) ethylene as required. -Α-olefin copolymer, (a2) ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer, (a3) ethylene-propylene copolymer 90% by mass or less of at least one resin selected from (a1) to (a3) of the polymer rubber, and (d) an unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof. With respect to 100 parts by mass of the thermoplastic resin component (A) containing 70% by mass or less of the resin modified with at least one selected, (e) an organic peroxide 0.001 to 1 part by mass, (f) (meth) acrylate-based and / or allylic crosslinking aid 0.003 to 2.5 parts by mass, and metal hydrate (B) 50 to 300 parts by mass The metal hydrate (B) is
(I) When the metal hydrate (B) is 50 parts by mass or more and less than 100 parts by mass, the metal hydrate pretreated with a silane coupling agent with respect to 100 parts by mass of the thermoplastic resin component (A) 25 parts by mass or more of the product;
(Ii) When the metal hydrate (B) is 100 parts by mass or more and 300 parts by mass or less, at least 1/4 of the metal hydrate (B) is pre-treated with a silane coupling agent. A composition having a composition,
A flame retardant resin composition characterized by being heated and kneaded at a temperature equal to or higher than the melting temperature of the thermoplastic resin component (A) and partially crosslinked in the presence of an organic peroxide.   2. The heat according to claim 1, wherein in the hydrogenated product of the random copolymer (b), the number of moles of the linear α-olefin unit structure generated by hydrogenation is ½ or more of the number of moles of the ethylene unit structure. Plastic resin composition. The crosslinking aid (f) has the general formula

(Here, R is H or CH ₃ , and n is an integer of 1 to 9.)
The flame retardant resin composition according to claim 1, wherein the flame retardant resin composition is a (meth) acrylate-based crosslinking aid represented by:   The flame retardant resin composition according to any one of claims 1 to 3, wherein the metal hydrate (B) is magnesium hydroxide.   The said silane coupling agent is a silane compound which has any 1 type in the group which consists of a vinyl group, a (meth) acryloyl group, an amino group, and an epoxy group at the terminal. The flame retardant resin composition according to Item 1.   A molded article comprising the flame retardant resin composition according to any one of claims 1 to 5 as a coating layer on the outside of a conductor or an optical fiber and / or an optical fiber core.   A molded part obtained by molding the flame retardant resin composition according to any one of claims 1 to 5. A flame retardant resin composition for a wiring material for pressure welding, comprising the flame retardant resin composition according to any one of claims 1 to 5.   The flame-retardant resin composition according to any one of claims 1 to 5, wherein (a1) an ethylene-α-olefin copolymer, (a2) an ethylene-vinyl acetate copolymer, ethylene- (meth) acryl. An acid copolymer or an ethylene- (meth) acrylic acid ester copolymer, (a3) at least one resin selected from (a1) to (a3) in an ethylene-propylene copolymer rubber, (b) Hydrogenated product of random copolymer mainly composed of aromatic vinyl compound and conjugated diene compound, (c) polypropylene resin, (d) unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof Resin modified with at least one selected from (e) organic peroxide, (f) (meth) acrylate-based and / or allylic crosslinking aid, and metallic water Things and (B) at the same time, the production method of the heated and kneaded at a melting temperature or higher of the resin component (a) ~ (d), partial crosslinking treatment flame retardant resin composition characterized by.   The flame retardant resin composition according to any one of claims 1 to 5, wherein, as a first step, (b) a hydrogenated random copolymer mainly comprising an aromatic vinyl compound and a conjugated diene compound, (c ) Polypropylene resin, (a1) ethylene-α-olefin copolymer, (a2) ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid copolymer, or ethylene- (meth) acrylic acid ester copolymer (A3) at least one resin selected from (a1) to (a3) in ethylene-propylene copolymer rubber, and (d) an unsaturated carboxylic acid or derivative thereof and (meth) acrylic acid or derivative thereof After the thermoplastic resin component (A) is obtained by heating and kneading a resin modified with at least one selected from the group consisting of the resin component (A) and ( ) Organic peroxide, (f) (meth) acrylate-based and / or allylic crosslinking aid, and metal hydrate (B) are heated and kneaded at a temperature equal to or higher than the melting temperature of the thermoplastic resin component (A), A method for producing a flame-retardant resin composition, comprising performing partial crosslinking treatment.

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