JP2005053092A - Flame retardant olefinic resin-coated metal wire and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame retardant olefinic resin-coated metal wire, which comprises a metal core wire and an outer olefinic resin layer and characterized in that there is strong adhesive force between the metal core wire and the outer olefinic resin layer and the outer olefinic resin layer has good flame retardancy, manufactured with high efficiency without requiring one process for forming an adhesive layer between the metal core wire and the outer olefinic resin layer, and its manufacturing method. <P>SOLUTION: In the fire retardant olefinic resin coated metal wire comprising the metal core wire, the adhesive layer and the outer olefinic resin layer, the outer olefinic resin layer comprises a flame retardant resin composition (C) wherein a flame retardant (B) is compounded with an olefinic base resin (A), and an adhesive (D) for constituting the adhesive layer and the flame retardant resin composition (C) are formed by a coextrusion molding method to be applied to the metal core wire. The manufacturing method of the flame retardant olefinic resin coated metal wire is also disclosed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a flame-retardant olefin resin-coated metal wire and a method for producing the same, and more specifically, a flame-retardant olefin resin-coated metal wire in which a metal core wire and an outer olefin resin layer are strongly bonded to each other and more efficient than the conventional method. Relates to a good manufacturing method.

Conventionally, vinyl chloride-coated iron wires have been used for fences, ginger nets, etc. However, problems of environmental impact and waste disposal have been pointed out, and replacement with olefin-based resins is required.
However, there are olefin resins that satisfy the characteristics required for the outer layer depending on the purpose of use of the wire, such as wear resistance and environmental fracture stress, but the olefin resin does not have sufficient adhesive properties, such as iron core wires. If a resin with insufficient adhesion to the core wire is used and processed into a wire mesh, net, fence, etc., the metal core wire and the outer coating resin will be distorted, causing cracks and peeling, and the core wire will rust. was there.

In order to solve these problems, for example, as described in Patent Document 1, an adhesive layer formed from a polyolefin emulsion having a carboxyl group introduced between an iron core wire plating layer and an outer resin layer. However, according to this, one step is required for forming the adhesive layer, and the solvent mixed in the emulsion must be distilled off, resulting in a reduction in production efficiency. In addition to this, even if this is adopted, the adhesion between the iron core wire and the resin layer cannot be said to be sufficient, and there has been a demand for the development of an olefin-based resin-coated metal wire that is more strongly bonded.
For this reason, the applicant of the present application disclosed in Japanese Patent Application No. 2002-162912 by forming and coating an adhesive and an outer layer olefin resin by a coextrusion molding method, and forming an olefin resin coating comprising an iron core wire, an adhesive layer and an outer layer olefin resin. Although iron wire was proposed and strong adhesion between the core wire and outer layer olefin resin was realized, this coating layer is flammable, and there is a further need for a flame retardant olefin resin coated metal wire having a coating layer that is difficult to burn. I reached.
Japanese Patent Laid-Open No. 11-277678 (claims, etc.)

  In view of the above problems, the object of the present invention is to eliminate the need for one step for forming an adhesive layer between the metal core wire and the outer olefin-based resin layer and a step for distilling off the solvent. Provided is a flame-retardant olefin resin-coated metal wire that can be produced and has a strong adhesive force between the metal core wire and the outer olefin-based resin layer, and the coating layer has good flame retardancy, and a method for producing the same. There is.

  The present inventors have intensively studied to solve the above-mentioned problems, and adopt a specific molding method, that is, a co-extrusion molding method, so that the above-mentioned known methods, a plurality of extrusion molding methods for each step, and a tandem extrusion molding method. In addition, it is found that excellent adhesion between the metal core wire and the outer olefin resin that is not obtained can be imparted, and the outer olefin resin layer further includes the flame retardant (B) in the olefin base resin (A). It was found that by using the flame retardant resin composition (C), a flame retardant olefin resin-coated metal wire having good flame retardancy was obtained, and the present invention was completed.

That is, according to the first invention of the present invention, in the olefin resin-coated metal wire comprising the metal core wire, the adhesive layer and the outer olefin resin layer, the outer olefin resin layer is formed on the olefin base resin (A). The adhesive (D) and the flame retardant resin composition (C) comprising the flame retardant resin composition (C) in which the flame retardant (B) is blended and constituting the adhesive layer are obtained by a coextrusion molding method. A flame-retardant olefin resin-coated metal wire is provided which is formed and coated.
Further, according to the second invention of the present invention, in the first invention, the ratio of the thickness of the adhesive layer and the outer olefin resin layer is 50/50 to 5/95. An olefin-based resin-coated metal wire is provided.
Furthermore, according to the third invention of the present invention, in the first invention, the ratio of the thickness of the adhesive layer and the outer olefin resin layer is 30/70 to 5/95. An olefin-based resin-coated metal wire is provided.

According to a fourth invention of the present invention, in any one of the first to third inventions, the adhesive (D) is a maleic anhydride graft-added ethylene resin, and the olefin base resin (A) is One or more selected from high density polyethylene having a density of 0.94 to 0.97 g / cm ³ and / or ethylene-α-olefin copolymer having a density of 0.88 to 0.97 g / cm ^3. A flame-retardant olefin-based resin-coated metal wire is provided.
According to the fifth invention of the present invention, in the fourth invention, the melt mass flow rate of the adhesive (D) is 0.1 to 35 g / 10 min, and the melt of the olefin-based base resin (A) Provided is a flame-retardant olefin resin-coated metal wire having a mass flow rate of 0.1 to 35 g / 10 min.
Furthermore, according to the sixth invention of the present invention, in any one of the first to fifth inventions, the flame retardant (B) is magnesium hydroxide, and the blending amount thereof is 100% by weight of the olefin base resin (A). The flame-retardant olefin resin-coated metal wire is provided in an amount of 75 to 200 parts by weight with respect to parts.

  On the other hand, according to the seventh invention of the present invention, in the method for producing an olefin resin-coated metal wire comprising a metal core wire, an adhesive layer, and an outer olefin resin layer, the outer olefin resin layer comprises an olefin base resin ( The flame retardant resin composition (C) in which the flame retardant (B) is blended with A) is used, and the adhesive (D) and the flame retardant resin composition (C) are formed into a metal core wire by a coextrusion molding method. A method for producing a flame-retardant olefin resin-coated metal wire according to any one of the first to sixth aspects is provided, wherein an adhesive layer and an outer olefin resin layer are formed.

  As described above, the present invention provides an olefin-based resin-coated metal wire comprising a metal core wire, an adhesive layer, and an outer olefin-based resin layer, wherein the outer-layer olefin-based resin is added to the olefin-based resin (A) and the flame retardant (B). A flame retardant comprising a flame retardant resin composition (C) blended with an adhesive (D) and a flame retardant resin composition (C) formed and coated by a coextrusion molding method. Olefin-based resin-coated metal wire and a method for producing this flame-retardant olefin-based resin-coated metal wire. This eliminates the need for the last step, thus improving the production efficiency, enhancing the adhesion between the metal core wire and the outer olefin resin layer, and providing the coating layer with good flame retardancy. Le Compared to resin-coated metal wire, it is possible to provide an environment load and waste flame-retardant olefin resin-coated metal wire problem is reduction in processing and its manufacturing method.

  Hereinafter, the flame-retardant olefin resin-coated metal wire of the present invention and the production method thereof will be described in detail for each item.

1. Metal Core Wire Examples of the metal core wire used in the present invention include iron wires, copper wires, aluminum wires, chromium wires, nickel wires, and the like, and any known wires may be used without any particular limitation.
The iron core wire used for the conventional vinyl chloride coated iron wire has a wide range of uses and is preferably used. The diameter of this iron core wire is 0.35 mm to 5.00 mm, and its surface is generally galvanized.
In the present invention, since the iron core wire and the outer olefin-based resin layer are strongly bonded as compared with the conventional product, the plating layer is not indispensable. However, for the long-term rust prevention effect, it is desirable to have the plating layer.

2. Olefin base resin (A)
In the present invention, the olefin base resin (A) used in the flame retardant resin composition (C) constituting the outer olefin resin layer is a known olefin resin having a known characteristic depending on the purpose of use. Resins can be appropriately selected and used.
Examples of the olefin base resin (A) include carbon numbers such as ethylene, propylene, butene-1, hexene-1, 3-methylbutene-1, 4-methylpentene-1, heptene-1, octene-1, and decene-1. Examples include a homopolymer of two or more α-olefins, a random, block or graft polymer composed of two or more of these monomers, or a mixture of polymers (including the same) composed of two or more of these monomers.

In the present invention, an ethylene-based resin can be suitably used as the olefin-based base resin (A).
Specific examples of the ethylene resin include polyethylene, ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and Philips method produced by a high-pressure radical method. Polyethylene or ethylene produced by a standard method, a Ziegler method, or a polymerization method using a single site catalyst such as a metallocene catalyst system, butene-1, pentene-1, hexene-1, octene-1, decene having 3 to 12 carbon atoms And copolymers with α-olefins such as -1, dodecene-1, 4-methylpentene-1.

The olefin base resin (A) can be used singly or in combination of two or more depending on the purpose of use. For example, in order to give wear resistance to the coated metal wire, as the olefin base resin (A), an ethylene homopolymer or an ethylene-α-olefin copolymer having a density of 0.94 to 0.97 g / cm ³ , So-called high density polyethylene can be suitably used.
Moreover, in order to give an environmental fracture stress resistance, a linear ethylene-α-olefin copolymer can be suitably used, and its density is 0.88 to 0.97 g / cm ³ , preferably A material having an ultra-low density of 0.88 to 0.92 g / cm ³ that is compatible with the flame retardant (B) and is capable of obtaining uniform dispersion of the flame retardant is preferable.
In this case, high-density polyethylene 95-60% by weight, preferably 80-65% by weight, and linear ethylene-α-olefin copolymer are used to impart both wear resistance and environmental fracture stress resistance. A mixed resin composed of a combination of 5 to 40% by weight, preferably 20 to 35% by weight may be used as the olefin base resin (A).

Also, ethylene-vinyl acetate copolymer or ethylene-ethyl acrylate copolymer, which is compatible with flame retardant and easily obtain uniform dispersion of flame retardant, and high-density polyethylene and linear ethylene with strong mechanical strength It is also suitable to use the α-olefin copolymer in combination as the olefin base resin (A).
Since the olefin base resin (A) used in the present invention is molded by coextrusion molding, its melt mass flow rate is 0.1 to 35 g / 10 min, preferably 0.5 to 10 g / 10 min. It is desirable to be.

3. Flame retardant (B)
In the present invention, the flame retardant (B) used in the flame retardant resin composition (C) constituting the outer olefin resin layer is an inorganic flame retardant, an organic halogen flame retardant, an organic phosphorus flame retardant, or the like. Can be mentioned.
Inorganic flame retardants include antimony trioxide, aluminum hydroxide, magnesium hydroxide, potassium hydroxide, calcium phosphate, zircon, titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, calcium carbonate, barium sulfate, barium borate, Barium metaborate, zinc borate, zinc metaborate, anhydrous alumina, molybdenum disulfide, clay, red phosphorus, diatomaceous earth, kaolinite, montmorillonite, hydrotalcite, talc, silica, white carbon, zeolite, asbestos, ritbon, huntite And hydromagnesite.

  Organic halogen flame retardants include hexabromobenzene, decabromodiphenyl oxide, polydibromophenylene oxide, bis (tribromophenoxy) ethane, ethylene bis-pentabromobenzene, ethylene bis-dibromonorbornane dicarboximide, ethylene bis-tetra Bromophthalimide, dibromoethyl-dibromocyclohexane, dibromoneopentyl glycol, tribromophenol, tribromophenol allyl ether, tetrabromo-bisphenol A derivative, tetrabromo-bisphenol S, tetradecabromo-diphenoxybenzene, tris (2,3-dibromo Propyl-1) isocyanurate, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydro) Ciethoxy-3,5-dibromophenyl) propane, pentabromophenol, pentabromotoluene, pentabromodiphenyl oxide, hexabromocyclododecane, hexabromodiphenyl ether, octabromophenol ether, octabromodiphenyl ether, octabromodiphenyl oxide, dibromoneopentyl Examples include glycol tetracarbonate, bis (tribromophenyl) fumaramide, N-methylhexabromophenylamine, brominated epoxy resin, chlorinated paraffin, chlorinated polyethylene, chlorinated polyolefin, and perchlorocyclopentadecane.

  Examples of organophosphorous flame retardants include tris (chloroethyl) phosphate, tris (monochloropropyl) phosphate, tris (dichloropropyl) phosphate, triallyl phosphate, tris (3-hydroxypropyl) phosphine oxide, tris (tribromophenyl) phosphate, Tetrakis (2-chloroethyl) ethylene-diphosphate, glycidyl-α-methyl-β-di (butoxy) phosphinylpropionate, dibutylhydroxymethyl phosphonate, di (butoxy) phosphinyl-propylamide, dimethylmethylphosphate , Amine phosphates such as ethylene-bis-tris (2-cyanoethyl) phosphonium bromide, ammonium polyphosphate, ethylenediamine phosphate and amine phosphate Nate and the like are exemplified.

  In the present invention, as the flame retardant (B), the above inorganic flame retardant, organic halogen flame retardant and organophosphorus flame retardant may be used alone or in combination of two or more (including the same type). It can also be used. For example, when the diameter of the metal core wire is small or when strong flame retardancy is required, an organic halogen flame retardant and an inorganic flame retardant may be combined to increase the flame retardancy. Even in this case, compared with the vinyl chloride resin, there are few halogen atoms contained in the coating layer, and since no plasticizer is used, a reduction in environmental burden can be achieved.

  The blending amount of the flame retardant (B) may be an effective amount, but is specifically 5 to 250 parts by weight with respect to 100 parts by weight of the olefin base resin (A). When the blending amount of the flame retardant (B) is less than 5 parts by weight, the flame retardancy is insufficient. On the other hand, when it exceeds 250 parts by weight, not only the moldability but also the mechanical properties as the coating resin layer are deteriorated.

In the present invention, an inorganic flame retardant having a small environmental load and few waste disposal problems can be suitably used.
Inorganic flame retardants are selected from higher fatty acids, higher fatty acid metal salts, higher fatty acid esters, higher fatty acid amides, higher alcohols, hardened oils, titanate coupling agents or silane coupling agents in order to improve dispersibility and fluidity. It is desirable that the surface is coated with 0.5 to 5% by weight of at least one surface treatment agent.
Specifically, the surface treatment agent is stearic acid, oleic acid, parimitic acid; sodium salts, calcium salts, magnesium salts of these higher fatty acids; methyl esters, ethyl esters, propyl esters, butyl esters of these higher fatty acids, Examples include octyl esters; amides of these higher fatty acids; octyl alcohol, myristyl alcohol, stearyl alcohol; beef tallow oil; isopropyl-tri (dioctyl phosphate) titanate; vinyltriethoxysilane. As the surface treatment method, either a wet method or a dry method can be used.

Among inorganic flame retardants, magnesium hydroxide, which is particularly safe and has a high melting point and excellent processing characteristics, can be suitably used.
As magnesium hydroxide, either synthetic magnesium hydroxide produced from seawater or the like and natural ore based on magnesium hydroxide produced by pulverizing natural brucite ore can be suitably used. The average particle size is preferably 40 μm or less, particularly preferably 0.2 to 6 μm, from the viewpoint of dispersibility and flame retardancy.
In addition, when using magnesium hydroxide as a flame retardant, the blending amount is based on 100 parts by weight of the olefin base resin (A) from the viewpoint of flame retardancy, mechanical properties of the coating layer, and surface properties. 75 to 200 parts by weight, preferably 90 to 180 parts by weight.

4). Adhesive (D)
In the present invention, the adhesive (D) used for the adhesive layer is made of an adhesive resin to which an extrusion molding method can be applied, and a carboxylic acid group-containing compound, a carboxylic acid ester-containing compound or an acid anhydride is added to an ethylene-based resin. Graft-added resin; ionomer; ethylene-maleic anhydride copolymer; or ethylene-α, β-carboxylic acid ester-maleic anhydride copolymer.
Here, the ethylene-based resin is the same as that described for the olefin-based resin (A).
Examples of the carboxylic acid group-containing compound used for graft addition include unsaturated carboxylic acids such as maleic acid, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, sorbic acid, crotonic acid, and citraconic acid.
Examples of the carboxylic acid ester-containing compound used for graft addition include methyl, ethyl, propyl and butyl esters of the carboxylic acid group-containing compound.
Examples of the acid anhydride used for graft addition include maleic anhydride, itaconic anhydride, citraconic anhydride, hymic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, 4-methylcyclohexene-1,2- Examples thereof include dicarboxylic acid anhydride and 4-cyclohexene-1,2-dicarboxylic acid anhydride.

The ionomer is a resin obtained by partially or completely neutralizing a copolymer of ethylene and an α, β-unsaturated carboxylic acid with a metal ion. Examples of the α, β-unsaturated carboxylic acid include acrylic acid and methacrylic acid, and examples of the metal ion include zinc and sodium.
In addition to these, an ethylene-maleic anhydride copolymer, an ethylene-ethyl acrylate-maleic anhydride copolymer, and the like can also be used as the adhesive (D) in the present invention.

Among these, maleic anhydride graft-added ethylene-based resins and ionomers can be preferably used.
Since the adhesive (D) used in the present invention is molded by a coextrusion molding method, its melt mass flow rate is 0.1 to 35 g / 10 min, preferably 0.5 to 10 g / 10 min. It is desirable.

5). Other compounds (E)
Various other additives and auxiliary materials can be blended in the flame-retardant resin composition (C) and the adhesive (D) used in the present invention. These additives and auxiliary materials include stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, nucleating agents, lubricants, fillers, dispersants, metal deactivators, neutralizing agents, and processing. Auxiliaries, mold release agents, foaming agents, anti-bubble agents, colorants, bactericides, antifungal agents and the like can be mentioned.
It is preferable to add an antioxidant to the flame retardant resin composition (C) and the adhesive (D) used in the present invention. Examples of the antioxidant include phenolic, phosphorous, amine-based, sulfur-based, and the like. They may be used alone or in admixture of two or more. The blending amount is 100 parts by weight of the resin component. On the other hand, it is about 0.001 to 5 parts by weight.

6). Flame retardant resin composition (C)
The flame retardant resin composition (C) used in the present invention contains a predetermined amount of an olefin base resin (A), a flame retardant (B), and other compound (E) as required. It can be prepared by mixing and kneading uniformly using a general method, for example, a kneader, a Banbury mixer, a continuous mixer, a roll mill or an extruder.
It is preferable to granulate the flame-retardant resin composition (C) obtained by melt-kneading, and then pellets having an average particle size of about 3.0 to 7.0 mm and use this for molding.

7). Method for Producing Flame Retardant Olefin Coated Metal Wire The flame retardant olefin resin coated metal wire of the present invention is a common die (die) having a metal core wire penetrated in the center using two extruders. The flame retardant resin composition (C) and the adhesive (D) are guided to the inside of the die and the metal flame is drawn to contact the flame retardant resin composition (C) and the adhesive (D) in the die opening or the die opening. It is obtained by extrusion molding to form and cover an adhesive layer and an outer olefin resin layer. As the die, a black box die, a multi-manifold die, a multi-slot die, or the like can be used.
At this time, in the present invention, the adhesive and the outer olefin-based resin layer may be extruded by heating to 190 to 250 ° C, preferably 190 to 230 ° C.
Strong adhesiveness is obtained only when the co-extrusion molding method is adopted, and cannot be obtained when the step extrusion molding method or the tandem extrusion molding method is adopted, as will be described in Examples. This strong adhesiveness is considered to be attributed to the temperature at the interface between the adhesive and the outer olefin resin during extrusion.

In the present invention, the intermediate layer may be coextruded between the adhesive layer and the outer olefin-based resin layer so that the resin layer has a three-layer structure. For example, an impact-resistant resin layer can be formed between the adhesive layer and the outer olefin resin layer using an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, or the like. In this case, a flame retardant olefin resin-coated metal wire can be produced in the same manner as described above by using one additional extruder and using three, and using one coextrusion die. In this case, the outer olefin-based resin layer thickness will be described below, but it is desirable from the viewpoint of flame retardancy to ensure 50% or more, more preferably 70% or more of the coating layer thickness.
It is desirable that the flame-retardant olefin resin-coated metal wire conforms to the standard of JIS G3543 “vinyl chloride-coated iron wire” because the vinyl chloride resin-coated iron wire can be easily replaced.

  In the flame-retardant olefin-based resin-coated metal wire of the present invention, since the thickness of the adhesive layer is practically about 30 to 250 μm from the indication of the coextrusion molding method, the flammable adhesive layer (or The total thickness of the adhesive layer and the intermediate layer) and the thickness of the outer olefin-based resin layer are preferably 50/50 to 5/95, more preferably 30/70 to 5/95, in order to obtain good flame retardancy. It is desirable that

  EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these Examples. In addition, evaluation used in this specification is based on the following methods, respectively.

"Evaluation"
I. Melt mass flow rate Measured in accordance with JIS K6922-1, under the test conditions of a temperature of 190 ° C. and a load of 2.16 kg.

II. Density Measured according to JIS K6922-2.

III. Adhesion III-1. Adhesiveness with metal core wire Cut the obtained flame-retardant olefin resin-coated metal wire, cut it into the resin layer with two knives parallel to the tangent of the metal core wire, and peel it off with both hands to bond Sex was evaluated. As the evaluation criteria, the case where it could not be peeled off was evaluated as “good”, and the case where it was not so was evaluated as “x”, and the case was rejected.
III-2. Adhesiveness between the adhesive layer and the outer olefin-based resin layer A cut was made between the adhesive layer and the outer olefin-based resin layer, and this was peeled off with both hands to evaluate the adhesiveness. As the evaluation criteria, the case where it could not be peeled off was evaluated as “good”, and the case where it was not so was evaluated as “x”, and the case was rejected.

IV. Flame retardancy IV-1. Horizontal combustion test It was performed according to JIS C3005. However, evaluation measured the time until self-extinguishing after 30-second flame contact.
Moreover, when carrying out self-extinguishing, it evaluated as (circle), it was set as the flame-retardant pass, and the case where it was not so was evaluated as x, and this was set as the flame-retardant failure.
IV-2.60 ° Inclined Combustion Test It was performed according to JIS C3005. However, evaluation measured the time until self-extinguishing after 30-second flame contact.
Moreover, when carrying out self-extinguishing, it evaluated as (circle), it was set as the flame-retardant pass, and the case where it was not so was evaluated as x, and this was set as the flame-retardant failure.

[Comparative Example 1]
As the adhesive (D), a maleic anhydride graft-added ethylene-ethyl acrylate copolymer (GA-004, manufactured by Nihon Unicar Co., Ltd.) having a melt mass flow rate of 1.6 g / 10 min is used, and an olefin base resin (A). As an ethylene homopolymer (HJ-560, manufactured by Nippon Polychem) having a density of 0.964 g / cm ³ and a melt mass flow rate of 7.0 g / 10 min. To 100 parts by weight of the olefin base resin (A), 1 part by weight of tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate methane was added as an antioxidant. The mixture was kneaded at 240 ° C. to prepare an antioxidant-containing olefin base resin.

Next, a surface galvanized iron wire (JIS G3547 SWMGS product) having a diameter of 2.3 mm is used as the metal core wire, and a common die composed of a multi-manifold die having a diameter of 3.2 mm and an adhesive and an olefin base resin 2 Using a single extruder, the adhesive (D) is 220 ° C., the antioxidant-containing olefin base resin (A) is 240 ° C., the coating layer thickness is 500 μm, the adhesive layer thickness and the outer layer olefin type The olefin resin-coated metal of Comparative Example 1 was coextruded at a take-up speed of 30 m so that the resin layer thickness was 100 μm and 400 μm (adhesive layer / outer olefin resin layer thickness ratio = 20/80), respectively. Got a line.
The adhesiveness of the obtained olefin resin-coated metal wire was evaluated. The results are shown in Table 1. The adhesiveness between the metal core wire and the adhesiveness between the adhesive layer and the outer olefin-based resin layer were not peeled off and were firmly adhered.
However, in the flame retardancy test, it was an olefin resin-coated metal wire that did not self-extinguish even in the horizontal burning test and flame retardancy was not recognized.

[Comparative Examples 2 and 3]
Density 0.964 g / cm ³ , melt mass flow rate 7.0 g / 10 min high density polyethylene (HJ-560, manufactured by Nippon Polychem) 35 wt%, density 0.905 g / cm ³ , melt mass flow rate 1.0 g / 10 65 wt% of ethylene-butene-1 copolymer (GRSN1539, manufactured by Dow Chemical) was mixed and used as the olefin base resin (A). To 100 parts by weight of the olefin base resin (A), magnesium hydroxide (Kisuma 5A higher fatty acid surface-treated product, manufactured by Kyowa Chemical) 45% by weight, ethylene bis-pentabromobenzene 45% by weight and antimony trioxide 10% by weight 70 parts by weight of the flame retardant (B) consisting of the combination and 1 part by weight of the same antioxidant as used in Comparative Example 1 were added and kneaded at 220 ° C. to prepare a flame retardant resin composition (C). This was made into pellets having an average particle size of about 4 mm and used in the following tests.

Comparative Example 1 except that the extrusion temperature of the flame retardant resin composition (C) was changed to 220 ° C. using the same adhesive (D) as in Comparative Example 1 and the prepared flame retardant resin composition (C). In the same manner as above, a flame-retardant olefin resin-coated metal wire was obtained.
In Comparative Example 2, the flame retardant resin composition (C) was not supplied to the multi-manifold die (ratio of adhesive layer / outer olefin resin layer thickness = 100/0). On the other hand, in Comparative Example 3, the adhesive (D) was not supplied to the multi-manifold die (ratio of adhesive layer / outer olefin resin layer thickness = 0/100).
Although the evaluation results are shown in Table 1, in Comparative Example 2, the adhesive layer was firmly bonded to the metal core wire. However, in the flame retardant test, the self-extinguishing was not performed in the horizontal combustion test, and the flame retardant Was not recognized. On the other hand, in Comparative Example 3, the flame retardancy passed, but the outer olefin-based resin layer could be easily peeled off from the metal core wire, and the adhesion was unacceptable.

[Examples 1 to 6]
A flame retardant olefin resin-coated metal wire is obtained in the same manner as in Comparative Example 2 except that the flame retardant resin composition (C) and the adhesive (D) are supplied, and the adhesion and flame retardancy are similarly evaluated. did.
In Example 1, the ratio of the adhesive layer thickness to the outer olefin resin layer thickness is 85/15, Example 2 is 60/40, Example 3 is 50/50, Example 4 is 35/65, Example 5 was adjusted to 20/80, and Example 6 was adjusted to 10/90, and the coating layer was formed and coated by a coextrusion molding method.
Although the evaluation result was shown in Table 1, the flame-retardant olefin resin-coated metal wire obtained in Examples 1 to 6 had strong adhesiveness.
As for flame retardancy, all were self-extinguishing and showed flame retardancy. As the proportion of the outer olefin resin layer thickness increases, the flame retardancy becomes stronger, especially in Example 5 (adhesive layer thickness / outer olefin resin layer thickness = 20/80 and Example 6 (same = 10/90)). It was an excellent flame retardant olefin resin-coated metal wire with strong flame retardancy and adhesion.

[Comparative Example 4]
A flame retardant olefin resin-coated metal wire having a ratio of adhesive layer thickness / outer olefin resin layer thickness of 20/80 in the same manner as in Example 5 except that the coextrusion molding method is replaced with a tandem extrusion molding method. And evaluated similarly.
Although the result was shown in Table 1, although it had favorable flame retardance, there was no adhesiveness of an adhesive bond layer and an outer layer olefin resin layer, and adhesiveness failed.

[Example 7]
A flame-retardant olefin-based resin-coated metal wire was obtained and evaluated in the same manner as in Example 5 except that the adhesive (D) was replaced with an ionomer (1652, manufactured by Mitsui Deyuplon Polychemical Co., Ltd.).
As shown in Table 1, this was an excellent flame-retardant olefin resin-coated metal wire that passed adhesiveness and had strong flame retardancy.

[Comparative Example 5, Examples 8 to 13]
Density 0.905 g / cm ³ , melt mass flow rate 1.0 g / 10 min ethylene-butene-1 copolymer (GRSN 1539, manufactured by Dow Chemical) 25 wt%, ethyl acrylate content 23 wt%, melt mass flow rate 0 75% by weight of ethylene-ethyl acrylate copolymer of 0.5 g / 10 min was mixed and used as the olefin base resin (A). To 100 parts by weight of this olefin base resin (A), 150 parts by weight of magnesium hydroxide (Kisuma 5A higher fatty acid surface-treated product, manufactured by Kyowa Chemical) and 1 part by weight of the same antioxidant as used in Comparative Example 1 were added. The flame-retardant resin composition (C) was prepared by kneading at 220 ° C., and the pellets having an average particle diameter of about 4 mm were used in the following tests.

The flame-retardant olefin resin-coated metal of Comparative Example 5 and Examples 8 to 13 was the same as Comparative Example 3 and Examples 1 to 6 except that the obtained flame-retardant resin composition (C) was used. Each line was obtained and evaluated similarly.
Table 2 shows the flame-retardant olefin resin-coated metal wires and the evaluation results thereof. Although the comparative example 5 which does not have an adhesive bond layer had favorable flame retardance, the adhesiveness of a metal core wire and an outer layer olefin resin layer was disqualified. On the other hand, Examples 8 to 13 had strong adhesiveness and all exhibited self-extinguishing in a flame retardancy test and exhibited good flame retardancy.
In particular, Example 12 (adhesive layer thickness / outer olefin-based resin layer thickness = 20/80) and Example 13 (same = 10/90) are excellent flame-retardant olefins having strong flame retardancy and adhesiveness. It was a resin-coated metal wire.

  The flame-retardant olefin resin-coated metal wire of the present invention has a strong adhesiveness between the resin coating layer and the metal core wire, and is flame-retardant, so it can be used effectively in the fields of wire mesh, nets, fences, etc. Can do.

Claims (7)

  In an olefin resin-coated metal wire comprising a metal core wire, an adhesive layer, and an outer olefin resin layer, the outer olefin resin layer is a flame retardant resin in which a flame retardant (B) is blended with an olefin base resin (A). The flame retardant characterized in that the adhesive (D) and the flame retardant resin composition (C) comprising the composition (C) and constituting the adhesive layer are formed and coated by a coextrusion molding method. Olefin resin coated metal wire.   The flame retardant olefin resin-coated metal wire according to claim 1, wherein the thickness ratio between the adhesive layer and the outer olefin resin layer is 50/50 to 5/95.   The flame retardant olefin resin-coated metal wire according to claim 1, wherein the thickness ratio between the adhesive layer and the outer olefin resin layer is 30/70 to 5/95. The adhesive (D) is a maleic anhydride graft-added ethylene-based resin, and the olefin-based base resin (A) is a high-density polyethylene having a density of 0.94 to 0.97 g / cm ³ and / or a density of 0.88. The flame-retardant olefin resin according to any one of claims 1 to 3, wherein the flame-retardant olefin resin is one or more selected from ethylene-α-olefin copolymers of ˜0.97 g / cm ^3. Coated metal wire.   The melt mass flow rate of the adhesive (D) is 0.1 to 35 g / 10 min, and the melt mass flow rate of the olefin base resin (A) is 0.1 to 35 g / 10 min. Item 5. A flame-retardant olefin-based resin-coated metal wire according to Item 4.   The flame retardant (B) is magnesium hydroxide, and the amount of the flame retardant (B) is 75 to 200 parts by weight with respect to 100 parts by weight of the olefin base resin (A). A flame-retardant olefin resin-coated metal wire according to claim 1.   In the method for producing an olefin-based resin-coated metal wire comprising a metal core wire, an adhesive layer, and an outer olefin-based resin layer, the outer-layer olefin-based resin layer is a difficulty in which a flame retardant (B) is blended with an olefin-based base resin (A). The flammable resin composition (C) is used, and the adhesive (D) and the flame retardant resin composition (C) are coated on the metal core wire by a coextrusion molding method, and the adhesive layer and the outer olefin resin layer. The method for producing a flame-retardant olefin resin-coated metal wire according to any one of claims 1 to 6, wherein: