JPH111581A - Low smoking flame-retardant resin composition and electric wire and cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition that emits no noxious gas as halogen gas on combustion, excellent in frame retardancy and low in smoking and particularly suitable as an insulation layer and sheath layer for electric wires and cables and provide electric wires and cables coated therewith. SOLUTION: The objective low smoking and flame retardant resin composition comprises (A) 100 pts.wt. of the resin component containing 100 pts.wt. of (a) an ethylene-α-olefin copolymer that is produced by using a single site catalyst and has a melt index of 0.1-10g/10 minutes and a density of 0.870-0.930 g/cm<3> , (b) 1-20 pts.wt. of an ethylene resin modified with a functional group- bearing compound, and (c) 1-15 pts.wt. of an organic peroxide-containing ethylene resin, (B) 40-250 pts.wt. of a metal hydroxide as Al(OH)3 or Mg(OH)2 , (C) 1-50 pts.wt. of zinc borate, (D) 0.1-10 pts.wt. of red phosphorus, and (E) 0.1-10 pts.wt. of silica. The objective electric wires and cables are produced by coating wires or cables with this resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition having low smoke emission and electric wires and cables.
Ethylene-α-olefin copolymer produced with a single-site catalyst is used as the main component of the resin. No toxic gas such as halogen gas is generated during combustion, and it has excellent flame retardancy and low smoke emission. The present invention relates to a resin composition suitably used for an insulating layer and a sheath layer of a cable, and an electric wire / cable coated with the composition.

[0002]

2. Description of the Related Art Conventionally, polyvinyl chloride resin compositions have been used as flame-retardant materials such as wire covering materials. However, the polyvinyl chloride resin composition generates a toxic halogen-containing gas when it is burned, or a heavy metal as a stabilizer, a plasticizer for imparting heat resistance, weather resistance, flexibility, processability, etc. However, these bleed to the resin surface, the surface of the molded product became sticky, the texture became poor, the part migrated to parts made from other resins in contact, and Problems such as oil resistance and printability may occur, and improvements have been demanded.

In order to overcome the above-mentioned disadvantages of the polyvinyl chloride resin composition, a resin composition in which a metal hydroxide such as aluminum hydroxide or magnesium hydroxide is blended with a polyolefin resin has been proposed. However, there are problems such as a large amount of smoke generated and a drip phenomenon.

[0004]

DISCLOSURE OF THE INVENTION The present invention overcomes the above-mentioned drawbacks of the polyvinyl chloride resin composition or the polyolefin resin composition containing a metal hydroxide, and provides not only flame retardancy but also flame resistance. No generation of toxic gas, reduced amount of smoke generation (excellent low smoke generation), no fire phenomena, other required mechanical properties, insulation, arc resistance, processing Resin composition having good heat resistance, low-temperature embrittlement resistance, heat resistance, oil resistance, flexibility, etc., suitable for use as a molding material for a coating layer of electric wires and cables, and an electric wire coated with the composition・ Provide cables.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to solve the above problems, and as a result, an ethylene-α-olefin copolymer produced using a single-site catalyst has excellent mechanical strength, Even if the functional group-containing compound-modified ethylene resin contains a large amount of metal hydroxide, it prevents the mechanical strength from decreasing, and further, the organic peroxide-containing ethylene resin exhibits the effect of preventing the drooling phenomenon during combustion. Heading that
By replacing polyvinyl chloride resin with these resins, compounding a metal hydroxide that is a non-halogen flame retardant, and further compounding zinc borate, a red phosphorus compound, and silica, flame retardancy is improved and combustion They found that the amount of smoke generated could be reduced, and demonstrated experimentally that all of the above problems could be solved only by combining the above three types of ethylene-based resins with additives such as specific flame retardants in specific mixing ratios After further study, the present invention was completed.

That is, the present invention provides a melt index of 0.1 to 10 g / 10 minutes and a density of 0.870 to 0.930.
g / cm ³ , 100 parts by weight of an ethylene-α-olefin copolymer produced using a single-site catalyst, 1 to 20 parts by weight of a functional group-containing compound-modified ethylene-based resin and an organic peroxide-containing ethylene-based resin 100 parts by weight of a resin component consisting of 1 to 15 parts by weight of a resin, 40 to 250 parts by weight of a metal hydroxide selected from aluminum hydroxide or magnesium hydroxide, 1 to 50 parts by weight of zinc borate, and 0.1% by weight of a red phosphorus compound. 1 to 10 parts by weight and silica 0.01 to
The present invention relates to a low-smoke, flame-retardant resin composition comprising 10 parts by weight. The present invention also relates to electric wires and cables coated with the above-described flame-retardant resin composition of the present invention.

[0007] The ethylene-α-olefin copolymer produced using the single-site catalyst used in the present invention can be treated with ethylene and α-olefin, for example, a carbon atom having a single-site catalyst described in detail below. It is a copolymer with 3 to 12 α-olefins. Specific examples of the α-olefin include propylene, butene-1,
Hexene-1,4-methylpentene-1, octene-
1, decene-1 and dodecene-1.

The ethylene-α-olefin copolymer used in the present invention has the following physical properties: a melt index of 0.1 to 10 g / 10 minutes, and a density of 0.870 to 0.1.
It has 930 g / cm ³ . Here, the melt index is measured in accordance with JIS K7210.
If it exceeds g / 10 minutes, the mechanical properties will be poor, which is not desirable. The density is measured in accordance with JIS K7112. If it is less than 0.870 g / cm ³ , heat resistance and oil resistance are poor, and if it exceeds 0.930 g / cm ³ , flexibility, elongation and workability are poor. Also, the flame retardant cannot be uniformly dispersed and held in the resin component, which is not desirable.

In the present invention, the single-site catalyst used in the production of the ethylene-α-olefin copolymer has the same active site (single-site) and has a high polymerization activity with respect to ethylene. It is. The ethylene-α-olefin copolymer produced with this catalyst has a narrower composition distribution and molecular weight distribution than those produced with conventional Ziegler-based catalysts or Phillips-based catalysts, and therefore has excellent mechanical properties. This single-site catalyst is also referred to as a metallocene catalyst or, as the inventor's name, a Kaminsky catalyst. Examples of the catalyst component include those represented by the following formulas (1) to (3).

The following formula (1): (Cp) _m MR _n R ′ _p (1) wherein Cp is an unsubstituted or substituted cyclopentadienyl group, and M is a transition of groups 4 to 10 of the periodic table. Metal
R and R 'are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarboxyl group, m is 1-3, n is 0-3, and p is 0-3. Wherein m + n + p is equal to the oxidation state (valence) of M].

[0011] the following equation (2) or _{(2 '): (C 5} R' m) p R "s (C 5 R 'm) MQ 3-ps (2) R" 3 (C 5 R' m) 2 MQ ′ (2 ′) (wherein C ₅ R ′ _m is an unsubstituted or substituted cyclopentadienyl group, wherein R ′s are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. , An alkenyl group, an aryl group, an alkylaryl group, an arylalkyl group, or two carbon atoms linked together to form part of a C ₄ -C ₆ ring, wherein R ″ is one or more carbon atoms. , Germanium, silicon, phosphorus or nitrogen atoms, or combinations thereof, which contain two C ₅
R by substituting 'by substituting the above _m ring group or one C ₅ R bridging them' _m ring above contain groups that bridges to M, when p is 0 x is 1 And in other cases x is always 0 and each Q is independently of each other an alkyl, alkenyl, aryl, alkylaryl, arylalkyl or halogen atom having 1 to 20 carbon atoms, Q ′ is an alkylidene group having 1 to 20 carbon atoms, s is 0 or 1, when s is 0, m is 5, and p is 0, 1 or 2, and s is When it is 1, m is 4 and p is 1
Is a transition metal compound represented by the formula: The transition metal compounds represented by the above formulas (1), (2) and (2 ′) are disclosed in JP-A-8-134121 and JP-A-8-134121.
JP-A-509773, JP-A-8-510290, and the like. The disclosure content of the above-mentioned patent publication is incorporated herein by this reference.

The following equation (3): Wherein M is a metal atom of Groups 3 to 10 of the periodic table or a lanthanoid, Cp is an unsubstituted or substituted cyclopentadienyl group bonded to M in an η ⁵ bond mode,
Is an atomic group containing boron or an element of group 14 of the periodic table, and optionally a sulfur atom or an oxygen atom,
The group may have atoms other than up to 20 hydrogen atoms, or Cp and Z together form a fused ring system, and X is independently of each other an anionic ligand or up to 30 hydrogen atoms. A neutral Lewis base ligand having an atom other than an atom, n is 0, 1, 2, 3, or 4, and
Is two less than the valency of M, and Y is an anionic or non-anionic ligand that binds Z and M, including a nitrogen, phosphorus, oxygen, or sulfur atom; Up to a number of atoms other than hydrogen or, if necessary, Y and Z together form a fused ring system). The transition metal compound represented by the above formula (3) is disclosed in
No. 306121, JP-A-7-500622 and the like. The disclosure content of the above-mentioned patent publication is incorporated herein by this reference.

The above catalyst further contains an activating cocatalyst. As the cocatalyst, aluminoxane having a high or low degree of polymerization, particularly methylaluminoxane, is suitable. So-called modified aluminoxanes are also suitable for use as the cocatalyst.

For the polymerization of the ethylene-α-olefin copolymer, a method such as a solution polymerization method, a suspension polymerization method, and a gas phase polymerization method can be preferably used. Generally, the temperature during the polymerization is 0 to 250 ° C. and the pressure is high (50 MPa
a or more), medium pressure (10 to 50 MPa) or low pressure (normal pressure to 10 MPa).

The functional group-containing compound-modified ethylene resin used in the present invention is obtained by graft-modifying an ethylene resin with a certain functional group-containing compound. As the functional group-containing compound, unsaturated carboxylic acids such as fumaric acid, acrylic acid, maleic acid,
Acid anhydrides such as itaconic acid, methacrylic acid, sorbic acid, crotonic acid or citraconic acid, such as maleic anhydride, itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, 4- Methylcyclohexene-1,2-dicarboxylic anhydride or 4-
Epoxy compounds such as cyclohexene-1,2-dicarboxylic anhydride, for example, glycidyl acrylate, glycidyl methacrylate, or allyl glycidyl ether; hydroxy compounds, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, or polyethylene glycol mono Metal salts, such as acrylates, such as sodium acrylate, sodium methacrylate, or zinc acrylate; or silane compounds, such as vinyl trichlorosilane, vinyl triethoxy silane, vinyl trimethoxy silane, or γ-methacryloxypropyl trimethoxy silane. can do.

The ethylene resin modified with the functional group-containing compound is not particularly limited, and any ethylene resin can be used, for example, ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate Copolymer (EEA), high-pressure low-density polyethylene (LDP)
E), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density ethylene-α-olefin copolymer (LLDPE), very low density linear ethylene-α-olefin copolymer (VLDPE) ) And an ethylene-α-olefin copolymer (SSC-PE) produced with the above-described single-site catalyst.

The amount of the functional group-containing compound to be graft-modified to the ethylene resin is preferably in the range of 0.05 to 10% by weight based on the resin. Known methods such as a solution method, a suspension method, and a melting method can be employed as the graft modification method. Among the above methods, when grafting a functional group-containing compound to an ethylene-based resin by a solution method, the ethylene-based resin and the functional group-containing compound are charged into a non-polar organic solvent, and a radical initiator is further added. This can be done by heating to a high temperature of 160 ° C. As the nonpolar organic solvent used at this time, hexane, heptane, benzene, toluene, xylene, chlorobenzene, tetrachloroethane and the like can be mentioned. Examples of the radical initiator include 2,5-dimethyl-2,5-di-tert-butylperoxyhexane, 2,5-dimethyl-2,5-di-tert-butylperoxyhexyne-3 and dicumyl peroxide. And the like. When the graft modification is performed by the suspension method, the ethylene-based resin and the functional group-containing compound are charged into a polar solvent such as water, and a radical initiator is further added, and the mixture is heated to a high temperature of 100 ° C. or higher under high pressure. Thus, a modified ethylene resin can be obtained. Further, in the case of graft modification by a melting method, an ethylene resin, a functional group-containing compound and a radical initiator are melted using a melt kneading machine commonly used in the field of synthetic resins, for example, an extruder, a Banbury mixer, a kneader or a roll mill. By kneading, a modified ethylene resin can be obtained.

The organic peroxide-containing ethylene resin is
1,1-bis-tert-butylperoxybenzoate, 2,
2-bistert-butylperoxybutane, tert-butylperoxybenzoate, dicumyl peroxide, tert-butylcumyl peroxide, 2,5-dimethyl-2,5
1 such as di-tert-butylperoxyhexane, 2,5-dimethyl-2,5-di-tert-butylperoxyhexyne-3
The organic peroxide having a decomposition temperature of 150 to 200 ° C. for obtaining a half-life for one minute is prepared by using the above EVA, EEA, LDPE, MDP
E, HDPE, LLDPE, VLDPE or SSC-
It is contained in an ethylene resin such as PE. The content of the organic peroxide is preferably in the range of 0.5 to 5 parts by weight based on 100 parts by weight of the ethylene resin. In addition, as a method of incorporating an organic peroxide into an ethylene-based resin, a predetermined amount of an ethylene-based resin and an organic peroxide are used at a temperature not lower than the melting point of the ethylene-based resin and not higher than the decomposition temperature of the organic peroxide. And melt kneading using a conventional melt kneading machine, for example, an extruder, a Banbury mixer, a kneader or a roll mill, or other methods.

The compounding ratio of the resin component is such that 1 to 20 parts by weight of the functional group-containing compound-modified ethylene resin and 100 parts by weight of the ethylene-α-olefin copolymer produced using the single-site catalyst are used. It is 1 to 15 parts by weight of a peroxide-containing ethylene resin. If the blending amount of the functional group-containing compound-modified ethylene resin is less than 1 part by weight, mechanical properties and flame retardancy are poor, and if it exceeds 20 parts by weight, flexibility and processability are poor. If the amount of the organic peroxide-containing ethylene-based resin is less than 1 part by weight, the amount of smoke generated during combustion increases, and mechanical properties and flame retardancy are poor. If it exceeds 15 parts by weight, processability is poor. In addition, the smell increases, which is not desirable.

The metal hydroxide used in the present invention is either one or both of aluminum hydroxide and magnesium hydroxide, and is preferably in the form of a fine powder, particularly having an average particle size of dispersibility and mechanical properties. From the viewpoint of flame retardancy, it is 0.1 to 20 μm. The metal hydroxide was subjected to a surface treatment such as coating with a fatty acid such as stearic acid, oleic acid, or palmitic acid or a metal salt thereof, paraffin, wax or a modified product thereof, an organic silane, or a compound such as an organic titanate. It can be used, and it is desirable to use a surface-treated one for improving the flame retardancy, and it is even more preferable to use a mixture with a surface treated with a different treating agent.

The metal hydroxide is composed of 100 parts by weight of an ethylene-α-olefin copolymer produced using a single-site catalyst, 1 to 20 parts by weight of a functional group-containing compound-modified ethylene resin, and an organic peroxide. With respect to 100 parts by weight of a resin component comprising 1 to 15 parts by weight of an ethylene resin,
40 to 250 parts by weight are blended. If this amount is less than 40 parts by weight, the flame retardancy is poor, and if it exceeds 250 parts by weight, the mechanical properties are poor, which is not desirable.

The zinc borate used in the present invention is:
From the viewpoint of dispersibility, mechanical properties, and flame retardancy, a fine powder having an average particle size of 0.1 to 20 μm is desirable. The mixing amount of the zinc borate is a total of 10 of the above three resin components.
It is 1 to 50 parts by weight relative to 0 parts by weight. If the amount is less than 1 part by weight, the amount of smoke generated at the time of combustion increases, and if it exceeds 50 parts by weight, the mechanical properties deteriorate, which is not desirable.

The red phosphorus compound used in the present invention is a flame retardant auxiliary containing red phosphorus as a main component, for example, a red phosphorus particle whose surface is coated with a stabilizer such as a thermosetting resin. It is. The coating prevents ignition caused by red phosphorus, particularly dust explosion, and also prevents deterioration of resin components caused by generation of phosphine and oxides. This red phosphorus compound has an average particle size of 10 to 20.
It is desirable that the particle size is μm in terms of dispersibility and the like. The compounding amount of the red phosphorus compound is a total of 100
It is 0.1 to 10 parts by weight based on parts by weight. This is 0.
If the amount is less than 1 part by weight, the flame retardancy is inferior and a fire drooping phenomenon occurs, and the amount of smoke generated during combustion increases. If the amount exceeds 10 parts by weight, the flame retardant effect reaches a peak and the mechanical properties are poor. The molded product tends to be red, which is not desirable.

The silica used in the present invention, ie, silicon dioxide, is preferably in the form of fine powder having an average particle size of 0.1 to 20 μm from the viewpoint of dispersibility, mechanical properties and flame retardancy. The amount of the silica is 0.1 to 10 parts by weight based on 100 parts by weight of the total of the three resin components. If the amount is less than 0.1 part by weight, the flame retardancy is inferior. If the amount exceeds 10 parts by weight, the effect of the flame retardancy reaches a peak and the mechanical properties are inferior.

The flame-retardant resin composition of the present invention may contain various additives and auxiliary materials according to the purpose of use as long as the properties of the present invention are not impaired. These various additives and auxiliary materials include stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, lubricants, processability improvers,
Examples thereof include a filler, a dispersant, a copper damage inhibitor, a neutralizing agent, a foaming agent, a coloring agent, and carbon black. Also,
The flame-retardant resin composition of the present invention may contain a small amount of an ethylene-based resin other than the ethylene-based resin or another polyolefin-based resin used in the present invention in a range that does not impair the properties of the present invention, depending on the purpose of use. You can also. These various additives, auxiliary materials, and other resins may be blended with the three types of resins used in the present invention, respectively, or may be blended with the flame-retardant resin composition of the present invention. . Furthermore, crosslinking may be performed by adding a crosslinking agent for crosslinking, for example, an organic peroxide, sulfur or a silane-based crosslinking agent or a crosslinking aid, or crosslinking may be performed by irradiation with ionizing radiation.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The flame-retardant resin composition of the present invention comprises a predetermined amount of an ethylene-α-olefin copolymer produced using a single-site catalyst, a functional group-containing compound-modified ethylene resin and Organic peroxide-containing ethylene-based resin, specific metal hydroxide, zinc borate, red phosphorus-based compound and silica, if necessary, the above-mentioned various additives and auxiliary materials, a crosslinking agent and other resins, etc. Individually in order,
Alternatively, some components are preliminarily mixed, or all components are mixed at once, and uniformly mixed and kneaded using a general method such as a kneader, a Banbury mixer, a continuous mixer, or an extruder. Can be manufactured.

The electric wire / cable of the present invention can be manufactured by extruding and covering the above-mentioned flame-retardant resin composition as an insulating layer or a sheath layer of the electric wire / cable.

[0028]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 Using the following raw materials, the compositions shown in Table 1 were kneaded with a Banbury mixer at 180 ° C. for 10 minutes, and then granulated to obtain pellets. Using the pellets prepared in this way, a hot press molding machine was used at 160 ° C and 150 kg / c.
Various properties were evaluated under the following conditions using the sheet obtained by molding for m ² for 3 minutes. The evaluation results are also shown in Table 1.

Raw Materials (1) Ethylene-α-olefin copolymer produced using a single-site catalyst: density 0.900 g / cm
³ , ethylene-melt index 0.8g / 10min
Octene-1 copolymer (manufactured by The Dow Chemical Company) (hereinafter referred to as component A). (2) Ethylene-α-olefin copolymer produced using a multi-site catalyst (Ziegler catalyst): density 0.910 g / cm ³ , melt index 0.5 g /
Ethylene-butene-1 copolymer (manufactured by Nippon Unicar) for 10 minutes (hereinafter referred to as component A '). (3) Functional group-containing compound-modified ethylene resin: Density 0.
900 g / cm ³ , melt index 0.8 g / 10
0.5% by weight maleic anhydride modified product of ethylene-butene-1 copolymer (manufactured by Nippon Unicar Co., Ltd.) (hereinafter referred to as component B). (4) Organic peroxide-containing ethylene resin: density 0.92
A high-pressure low-density polyethylene containing 1.5% by weight of dicumyl peroxide at 5 g / cm ³ and a melt index of 2.3 g / 10 minutes (hereinafter referred to as component C). (5) Metal hydroxide: a 1: 1 mixture of magnesium hydroxide surface-treated with stearic acid and magnesium hydroxide surface-treated with silane (hereinafter referred to as component D). (6) Zinc borate: average particle size 5 μm (hereinafter referred to as component E). (7) Red phosphorus compound: Red phosphorus particles whose surfaces are coated with a thermosetting resin (phenol resin). Average particle size 15 μm (hereinafter referred to as component F). (8) Silica: average particle size 1 μm (hereinafter referred to as component G).

Evaluation method (1) Melt index Measured according to JIS K7210 under the conditions of a load of 2.16 kg and a measurement temperature of 190 ° C. (2) Flow ratio This value is a measure of the molecular weight distribution, and the higher the value, the better the processability. (Flow ratio) = (Flow index) ÷ (Melt index) The evaluation of the flow index was performed in accordance with JIS K7210, and the measurement conditions were a load of 21.6 kg and a measurement temperature of 1.
90 ° C. (3) Tensile strength and elongation A sheet having a thickness of 1 mm is used.
Perform according to 0. (4) Flame retardancy test (4) -1 Oxygen index: A sheet having a thickness of 3 mm is used in accordance with JIS K7201. The results are expressed as oxygen indices, the higher the value, the better the flame retardancy. (4) -2 Fire sag: Use a sheet having a thickness of 2.5 mm according to the flammability B method of JIS K6911. (3) -3 Smoke emission: A sheet having a thickness of 4 mm was used in accordance with ASTM E662, and the value of the highest point of smoke generation was adopted. The smaller the value, the smaller the amount of smoke generated, that is, the lower the smoke-generating property, and in this example, 150 or less was regarded as acceptable.

Examples 2 to 3 and Comparative Examples 1 to 6 The same operation as in Example 1 was repeated using a composition having the composition shown in Table 1. Table 1 also shows the evaluation results.
Are shown together.

[0033]

[Table 1] (Footnotes) ^{* 1} Components A to G of raw materials are as described in Example 1. ^{* 2} Items and units of the evaluation result are as follows. MI: Melt index (unit: g / 10 minutes) FR: Flow ratio (no unit) Tensile strength: unit MPa Elongation: unit% Flame retardancy: No unit for both oxygen index and fire dripping. dr means that dripping has occurred. Smoke emission: no unit

The following is clear from the results shown in Table 1. First, the examples of the present invention are excellent in all evaluation results. In contrast, Comparative Examples 1 to 6 are all inferior to Examples 1 to 3 in at least one item. Comparative Example 1 was a multi-site catalyst (Ziegler-based catalyst) instead of the ethylene-α-olefin copolymer (component A) produced with a single-site catalyst as the main resin component.
Using the ethylene-α-olefin copolymer (component A ′) produced in the above, but compared with Example 2 in which the other components and their blending amounts were the same, the mechanical strength and oxygen index Inferior in fire retardancy and flame retardancy. In Comparative Example 2, the functional group-containing compound-modified ethylene-based resin (component B) was not blended, but the mechanical strength and the flame retardancy in the sag were inferior. In Comparative Example 3, the organic peroxide-containing ethylene-based resin (component C) was not blended, but the flame retardancy in mechanical strength and the sag was inferior, and the amount of generated smoke was large. In Comparative Example 4, zinc borate (component E) was not added, but the flame retardancy in oxygen index was inferior and the amount of generated smoke was very large. In Comparative Example 5, the red phosphorus compound (component F) was not blended, but the flame retardancy in terms of oxygen index was poor, dripping occurred in the case of dripping, and the amount of generated smoke was particularly large. In Comparative Example 6, silica (component G) was not blended, but the flame retardancy due to drooling was inferior.

[0035]

As described in detail above, the low-smoke flame-retardant resin composition of the present invention contains an ethylene-α-olefin copolymer produced using a single-site catalyst as a main component, In addition, a functional group-containing compound-modified ethylene resin and an organic peroxide-containing ethylene resin are used as resin components, and specific metal hydroxide, zinc borate, red phosphorus compound and silica are blended in specific amounts, respectively. so,
High flame retardancy, low smoke generation during combustion, no generation of harmful gases such as halogen gas, and mechanical properties, workability, insulation, arc resistance, low temperature embrittlement resistance Good heat resistance, oil resistance and flexibility. Also,
Wires and cables coated with the flame-retardant resin composition of the present invention having such excellent properties are flame-retardant, mechanical properties, insulating properties, arc resistance, low-temperature embrittlement resistance, Heat-resistant,
It has excellent oil resistance and flexibility, and its workability is also good.
Moreover, since the amount of smoke generated during combustion is small and no toxic gas is generated, it is preferable in terms of environmental protection and the safety is high.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 5/14 C08K 5/14 H01B 3/44 H01B 3/44 F 7/34 7/34 B // (C08L 23/08 23 : 04 23:26)

Claims (2)

[Claims] 1. Melt index 0.1 to 10 g / 1
0 min, density 0.870-0.930 g / cm ³ ,
Ethylene-α produced using a single-site catalyst
A resin component 1 comprising 100 parts by weight of an olefin copolymer, 1 to 20 parts by weight of a functional group-containing compound-modified ethylene resin, and 1 to 15 parts by weight of an organic peroxide-containing ethylene resin.
00 parts by weight, 40 to 250 parts by weight of a metal hydroxide selected from aluminum hydroxide or magnesium hydroxide,
1 to 50 parts by weight of zinc borate, red phosphorus compound 0.1 to 1
A low-smoke, flame-retardant resin composition comprising 0 parts by weight and 0.01 to 10 parts by weight of silica. 2. An electric wire or cable coated with the flame-retardant resin composition according to claim 1.