JP5780479B1 - Non-halogen multilayer insulated wire - Google Patents

Abstract

[PROBLEMS] To provide a non-halogen multilayer insulated wire excellent in abrasion resistance, hydrolysis resistance, flame retardancy, heat resistance, low smoke generation, low toxicity, insulation resistance at high temperatures, and particularly compliant with EN standards (European standards). To do. A non-halogen multilayer insulated wire comprising a conductor, an inner layer coated with a polyolefin-based resin composition on the conductor, and a coating layer formed on the outside of the inner layer and coated with a polyester-based resin composition. The coating layer performs a reciprocating operation while applying a load of 9 N with a wear needle, and has a wear resistance of 150 times or more until short-circuiting, and a constant temperature and humidity chamber of 85 ° C./85% RH. After standing for days, after carrying out hydrolysis resistance that does not cause cracks due to winding by self-diameter and a combustion test based on IEC603332-1, from the upper support part to the carbonization part, to the upper part of the electric wire The flame retardance is 50 mm or more and the distance to the lower part of the electric wire is 540 mm or less, and the elongation remaining ratio in the tensile test after heat treatment in accordance with JISC3005 is 70% or more. Heat resistance, low smoke generation with a smoke transmission rate of 70% or more according to the smoke concentration test according to EN50268.2, and toxicity index according to toxicity test according to EN503059.2 is 6 or less It has low toxicity and high-temperature insulation resistance with a measured value of insulation resistance at high temperatures of 600 MΩ / km or more in accordance with EN50305.6.4. [Selection] Figure 1

Description

  The present invention relates to a non-halogen multilayer insulated wire excellent in abrasion resistance, hydrolysis resistance, flame retardancy, heat resistance, low smoke generation, low toxicity, insulation resistance at high temperatures, and particularly compliant with EN standards (European standards). Is.

  Chloroprene rubber blends, chlorosulfone, which balances oil and fuel resistance, low-temperature properties, flame resistance, flexibility, and cost, are used for moving wires and cables used in railway vehicles and cables and cranes. Halogenated rubber blends such as chlorinated polyethylene blends, chlorinated polyethylene blends, and fluororubber blends are used.

  However, these halogen-containing substances generate a large amount of toxic and harmful gases during combustion, and generate extremely toxic dioxins depending on the incineration conditions. For this reason, from the viewpoint of safety at the time of fire and reduction of environmental burden, electric wires and cables using a halogen-free material (non-halogen material) that does not contain a halogen substance as a covering material have become widespread.

  On the other hand, in Europe where the railway vehicle network is developed, the adoption of the regional standard called EN standard (European standard) is spreading.

  In such EN standards, non-halogens with wear resistance, hydrolysis resistance, flame resistance, heat resistance, and low smoke generation are associated with the risk of serious accidents if there are defects in electric wires and cables for railway vehicles. The material is required to be used for electric wires and cables for railway vehicles.

  There exists an electric wire of patent document 1 as what responds to these requirements.

  In Patent Document 1, an inner layer made of a polyester resin composition containing a polyester resin (polybutylene terephthalate, polybutylene naphthalate, etc.), a polyester block copolymer, a hydrolysis inhibitor, and a calcined clay on the outer periphery of a conductor; A multilayer insulated wire comprising a polyester resin (polybutylene terephthalate, polybutylene naphthalate, etc.), a polyester block copolymer, a hydrolysis inhibitor, a calcined clay, and an outer layer made of a polyester resin composition containing magnesium hydroxide The polyester block copolymer comprises 20 to 70% by mass of a hard segment (a) containing terephthalic acid as a main component of polybutylene terephthalate having 60 mol% or more per dicarboxylic acid component, and an acid component constituting the polyester. Is an aromatic dicarboxylic acid Soft segment (a) 80 to 9 comprising 90 to 90 mol%, 6 to 12 carbon straight chain aliphatic dicarboxylic acid 1 to 10 mol%, and the diol component is a straight chain diol having 6 to 12 carbon atoms Polyester block copolymer having a melting point (T) in the range of the formula TO-5> T> TO-60 (TO: melting point of polymer comprising components constituting a hard segment) A multilayer insulated wire that is a coalesced is disclosed.

JP2011-228189A

  In the EN standard, in addition to the above characteristics, it is required to have low toxicity and excellent insulation resistance at high temperatures. However, in the prior art such as the above-mentioned Patent Document 1, it is the actual situation that an electric wire / cable having these required characteristics cannot be obtained.

  Therefore, the object of the present invention is excellent in abrasion resistance, hydrolysis resistance, flame retardancy, heat resistance, low smoke generation, low toxicity, insulation resistance at high temperature, and particularly non-halogen compliant with EN standards (European standards). The object is to provide a multilayer insulated wire.

In order to achieve the above object, the present invention provides a non-halogen multilayer insulated wire of the following [1].
[1] In a non-halogen multilayer insulated wire comprising a conductor, an inner layer coated with a polyolefin-based resin composition on the conductor, and a coating layer formed on the outside of the inner layer and coated with a polyester-based resin composition,
The coating layer is
A reciprocating operation is performed while applying a load of 9 N with a wear needle, and the number of reciprocations until a short circuit is 150 times or more,
Hydrolysis resistance in which cracks do not occur due to winding with a self-diameter after standing in an oven at 85 ° C./85% RH for 30 days,
After carrying out a combustion test in accordance with IEC603332-1, the distance from the upper support part to the carbonization part, the distance to the upper part of the electric wire is 50 mm or more and the distance to the lower part of the electric wire is 540 mm or less,
Heat resistance with an elongation percentage of 70% or more in a tensile test after heat treatment in accordance with JISC3005;
Low smoke emission with a smoke transmittance of 70% or more generated by a smoke concentration test according to EN50268.2,
Low toxicity with a toxicity index of 6 or less according to toxicity tests according to EN 50305.9.2,
A non-halogen multi-layer insulated wire characterized by having a high temperature insulation resistance of 600 MΩ / km or more according to EN50305.6.4.

  According to the present invention, non-halogen multilayer insulation excellent in abrasion resistance, hydrolysis resistance, flame retardancy, heat resistance, low smoke generation, low toxicity, insulation resistance at high temperature, and particularly conforming to EN standards (European standards) Electric wires can be provided.

It is sectional drawing of the non-halogen multilayer insulated wire which concerns on embodiment of this invention. It is a figure for demonstrating the abrasion-resistance test method which tests the abrasion resistance of the electric wire in an Example. (A) is a side view, (b) is a front view. It is a figure for demonstrating the IEC combustion test method which tests the flame retardance of the electric wire in an Example.

(Configuration of non-halogen multilayer insulated wire)
FIG. 1 is a cross-sectional view of a non-halogen multilayer insulated wire according to an embodiment of the present invention.

  As shown in FIG. 1, the non-halogen multilayer insulated wire 1 according to the embodiment of the present invention includes a conductor 10, a high density polyethylene, and ethylene having an ethyl acrylate content (EA amount) of 9 to 35 mass% on the conductor 10. A polyolefin-based resin composition containing either an ethyl acrylate copolymer or an ethylene vinyl acetate copolymer having a vinyl acetate content (VA amount) of 15 to 45% by mass in a mass ratio of 50 to 90:50 to 10. The coated inner layer 20 includes a base polymer mainly composed of a polyester resin on the outer side of the inner layer 20, and 50 to 150 parts by mass of a polyester block copolymer with respect to 100 parts by mass of the base polymer, a hydrolysis inhibitor. Polyester containing 0.5-5 parts by mass, 0.5-5 parts by mass of inorganic porous filler, and 10-30 parts by mass of magnesium hydroxide It is preferable to provide an outer layer 30 coated with the resin composition.

  As the conductor 10, the conductor generally used in the insulated wire can be used.

  The inner layer 20 will be described below.

  The polyolefin-based resin composition used for the inner layer 20 has a high-density polyethylene, an ethylene acrylate copolymer (EEA) having an ethyl acrylate content of 9 to 35% by mass, or a vinyl acetate content of 15 to 45% by mass. It is preferable to contain any of ethylene vinyl acetate copolymer (EVA) in a mass ratio of 50 to 90:50 to 10.

  The total amount of the high-density polyethylene and EEA or EVA in the polyolefin resin composition is preferably 65% by mass or more, more preferably 75% by mass or more, still more preferably 85% by mass or more of the polyolefin resin composition, 95 The mass% or more is most preferable.

The reason for using high density polyethylene is to improve mechanical strength. The content of the high density polyethylene is a mass ratio to the ethylene ethyl acrylate copolymer or the ethylene vinyl acetate copolymer (that is, the percentage in the total mass of the high density polyethylene and the ethylene ethyl acrylate copolymer or the ethylene vinyl acetate copolymer). If it is less than 50%, the abrasion resistance is insufficient, and if it is more than 90%, the flame retardancy is insufficient. The high-density polyethylene in the embodiment of the present invention is not particularly limited, but, for example, one having a density of 0.942 g / cm ³ or more is preferable.

  The reason for using ethylene ethyl acrylate copolymer or ethylene vinyl acetate copolymer is to form a carbonized layer during combustion. The reason why the ethyl acrylate content (EA amount) of the ethylene ethyl acrylate copolymer is 9 to 35% by mass is that the flame retardancy is reduced when it is less than 9% by mass, and the mechanical properties are remarkably deteriorated when it is more than 35% by mass. Because. In addition, the vinyl acetate content (VA amount) of the ethylene vinyl acetate copolymer is set to 15 to 45% by mass. When the content is less than 15% by mass, the flame retardancy decreases. It is because it falls.

  Further, the content of the ethylene ethyl acrylate copolymer or ethylene vinyl acetate copolymer is determined by the mass ratio to the high density polyethylene (that is, the total mass of the high density polyethylene and the ethylene ethyl acrylate copolymer or ethylene vinyl acetate copolymer). The reason why the content is limited to 10 to 50% is that the flame retardancy is insufficient when it is less than 10%. On the other hand, if it exceeds 50%, the content ratio of the high-density polyethylene becomes small and the wear resistance becomes insufficient.

  The polyolefin resin composition used for the inner layer 20 is a polyolefin other than high-density polyethylene, ethylene ethyl acrylate copolymer, and ethylene vinyl acetate copolymer as long as it does not impair the expression of flame retardancy and wear resistance. For example, low density polyethylene, medium density polyethylene, linear low density polyethylene, linear ultra low density polyethylene, ethylene-methyl methacrylate copolymer, ethylene-methyl acrylate copolymer, Examples thereof include an ethylene-styrene copolymer, an ethylene-maleic anhydride copolymer, and a maleic anhydride grafted linear low density polyethylene. These polyolefin resins may be modified with maleic acid or a derivative thereof. These may be used alone or in combination of two or more.

  Next, the outer layer 30 will be described below.

  The polyester-based resin composition used for the outer layer 30 includes a base polymer mainly composed of a polyester resin, and 50 to 150 parts by mass of a polyester block copolymer with respect to 100 parts by mass of the base polymer. It is preferable that 0.5-5 mass parts of agents, 0.5-5 mass parts of inorganic porous fillers, and 10-30 mass parts of magnesium hydroxide are included.

  The “base polymer mainly composed of a polyester resin” means that the polyester resin is the most abundant component in the base polymer. That is, it means that the content of the polyester resin in the base polymer is 50% by mass or more. Preferably, it is 70 mass% or more, More preferably, it is 80 mass% or more, More preferably, it is 90 mass% or more. The reason for using the polyester resin is that it is excellent in heat resistance and wear resistance.

  Examples of the polyester resin include polybutylene naphthalate resin (PBN), polybutylene terephthalate resin (PBT), polytrimethylene terephthalate resin, polyethylene naphthalate resin, and polyethylene terephthalate resin. In the range which does not impair the effect of this invention, these can be used in combination and can be mixed and used for polypropylene resin, polyethylene resin, etc. A specific description will be given below using PBN and PBT as examples.

  The polybutylene naphthalate resin in the embodiment of the present invention is a polyester having naphthalene dicarboxylic acid, preferably naphthalene-2,6-dicarboxylic acid as a main acid component and 1,4-butanediol as a main glycol component, The polyester is such that all or most of the repeating units (usually 90 mol% or more, preferably 95 mol% or more) are butylene naphthalene dicarboxylate.

  The polybutylene naphthalate resin can copolymerize the following components as long as the physical properties are not impaired.

  Examples of the acid component include aromatic dicarboxylic acids other than naphthalenedicarboxylic acid, such as phthalic acid, isophthalic acid, terephthalic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylmethanedicarboxylic acid, diphenylketonedicarboxylic acid, diphenylsulfide Examples include dicarboxylic acid, diphenylsulfone dicarboxylic acid, aliphatic dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, and alicyclic dicarboxylic acid such as cyclohexane dicarboxylic acid, tetralin dicarboxylic acid, decalin dicarboxylic acid and the like.

  As glycol components, ethylene glycol, propylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, neopentyl glycol, cyclohexanedimethanol, xylylene glycol, diethylene glycol, polyethylene glycol, bisphenol A, catechol, resorcinol Examples include quinol, hydroquinone, dihydroxydiphenyl, dihydroxydiphenyl ether, hydroquinone, dihydroxydiphenyl, dihydroxydiphenyl ether, dihydroxydiphenylmethane, dihydroxydiphenyl ketone, dihydroxydiphenyl sulfide, and dihydroxydiphenyl sulfone.

  Examples of the oxycarboxylic acid component include oxybenzoic acid, hydroxynaphthoic acid, hydroxydiphenylcarboxylic acid, and ω-hydroxycaproic acid.

  It should be noted that trifunctional or higher functional compounds such as glycerin, trimethylpropane, pentaerythritol, trimellitic acid, pyromellitic acid and the like may be copolymerized as long as the polyester does not substantially lose molding performance.

  Although there is no restriction | limiting in particular in the terminal carboxyl group density | concentration of the polybutylene naphthalate resin in this Embodiment, The smaller one is desirable.

  The polybutylene naphthalate resin is obtained by polycondensation of naphthalene dicarboxylic acid and / or a functional derivative thereof and butylene glycol and / or a functional derivative thereof using a conventionally known aromatic polyester production method.

  The polybutylene terephthalate resin in the embodiment of the present invention is a polyester having a repeating unit of butylene terephthalate as a main component, and 1,4-butanediol as a polyhydric alcohol component, terephthalic acid as a polyvalent carboxylic acid component or its It is a polyester having a main repeating unit of a butylene terephthalate unit obtained by using an ester-forming derivative. A main repeating unit means that a butylene terephthalate unit is 70 mol% or more in all the polyhydric carboxylic acid-polyhydric alcohol units. Further, the butylene terephthalate unit is preferably 80 mol% or more, more preferably 90 mol%, and still more preferably 95 mol% or more.

  Examples of polyvalent carboxylic acid components other than terephthalic acid used in polybutylene terephthalate resin include 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, isophthalic acid, phthalic acid, trimesic acid, trimellitic acid, etc. Aromatic polycarboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid and other aliphatic dicarboxylic acids, cyclohexanedicarboxylic acid and other alicyclics Examples thereof include dicarboxylic acids or ester-forming derivatives of the above polyvalent carboxylic acids (for example, lower alkyl esters of polyvalent carboxylic acids such as dimethyl terephthalate). These polyvalent carboxylic acid components may be used alone or in combination as a polyvalent carboxylic acid component other than terephthalic acid.

  Examples of polyhydric alcohol components other than 1,4-butanediol used in polybutylene terephthalate resin include ethylene glycol, diethylene glycol, propylene glycol, neopentyl glycol, pentanediol, hexanediol, glycerin, trimethylolpropane, penta Aliphatic polyhydric alcohols such as erythritol, alicyclic polyhydric alcohols such as 1,4-cyclohexanedimethanol, aromatic polyhydric alcohols such as bisphenol A and bisphenol Z, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly And polyalkylene glycols such as tetramethylene oxide glycol. These polyhydric alcohol components may be used alone or as a polyhydric alcohol component other than 1,4-butanediol.

  The polybutylene terephthalate resin used in the present embodiment preferably has a terminal carboxyl group equivalent of 50 (equivalent / ton, hereinafter referred to as eq / t) or less, more preferably 40 from the viewpoint of hydrolysis resistance. (Eq / t) or less, more preferably 30 (eq / t) or less. When the terminal carboxyl group equivalent exceeds 50 (eq / t), it is not preferable from the viewpoint of hydrolyzability.

  The polybutylene terephthalate resin in the embodiment of the present invention may be used singly as long as the effects of the present invention are exhibited, or may be used in a plurality of mixtures having different terminal carboxyl group concentrations, melting points, catalyst amounts, etc. Good.

  The polyester resin composition used for the outer layer 30 includes a polyester block copolymer. The reason for adding the polyester block copolymer is to further increase the heat resistance and to provide flexibility.

  The polyester block copolymer is preferably added in the range of 50 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the base polymer. If it is less than 50 parts by mass, the desired flexibility cannot be obtained, and if it exceeds 150 parts by mass, low toxicity and wear resistance are insufficient.

  The polyester block copolymer used in the embodiment of the present invention has a hard segment of 60 mol% or more (preferably 70 mol% or more) containing polybutylene terephthalate as a main constituent, but in addition to benzene other than terephthalic acid. Or a diol such as an aromatic dicarboxylic acid containing a naphthalene ring, an aliphatic dicarboxylic acid having 4 to 12 carbon atoms, an aliphatic diol having 2 to 12 carbon atoms other than tetramethylene glycol, and an alicyclic diol such as cyclohexanedimethanol. It may be polymerized, and the copolymerization ratio is less than 30 mol%, preferably less than 10 mol%, based on the total dicarboxylic acid. The smaller the copolymerization ratio, the higher the melting point and the better. However, copolymerization is also performed to increase flexibility. However, when the copolymerization ratio is increased, the compatibility between the polyester block copolymer and the polybutylene naphthalate resin is lowered, and the wear resistance may be impaired.

  On the other hand, the soft segment of the polyester block copolymer is 99 to 90 mol% aromatic dicarboxylic acid, 1 to 10 mol% linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms, and the diol component is 6 to 6 carbon atoms. Polyester which is 12 linear diols. Examples of the aromatic dicarboxylic acid include terephthalic acid and isophthalic acid. Examples of the linear aliphatic dicarboxylic acid having 6 to 12 carbon atoms include adipic acid and sebacic acid. The amount of the linear aliphatic dicarboxylic acid is preferably 1 to 10 mol%, more preferably 2 to 5 mol%, based on the total acid component of the polyester constituting the soft segment. If it is 10 mol% or more, the compatibility with the polybutylene naphthalate resin is lowered. Moreover, since the softness | flexibility of a soft segment will be impaired at 1 mol% or less, the softness | flexibility of this polyester-type resin composition is impaired as a result. Since the polyester constituting the soft segment needs to be amorphous or low crystalline, it is preferable to use isophthalic acid for 20 mol% or more of the total acid component constituting the soft segment. In addition, the soft segment can be copolymerized with some other components in the same manner as the hard segment. However, since the compatibility with the polybutylene naphthalate resin is lowered, the amount of the copolymer component is preferably 10 mol% or less, more preferably 5 mol% or less.

  In the polyester block copolymer used in the present embodiment, the mass ratio of the hard segment to the soft segment is preferably 20 to 50:80 to 50, more preferably 25 to 40:75 to 60. When the mass ratio of the hard segment is larger than the above range, it is not preferable because it becomes hard and difficult to use, and when the mass ratio of the soft segment is larger than the above range, the crystallinity is reduced and handling is difficult. This is not preferable.

  Moreover, the segment length of the soft segment and hard segment of the polyester block copolymer is preferably about 500 to 7000, more preferably 800 to 5000 when expressed in terms of molecular weight, but is not particularly limited. . Although it is difficult to directly measure the segment length, for example, the composition of the polyester constituting the soft segment and the hard segment, the melting point of the polyester comprising the components constituting the hard segment, and the obtained polyester block copolymer From the melting point, it can be estimated using the Flory equation.

  The melting point (T) of the polyester block copolymer is preferably in the range of “TO-5> T> TO-60” (TO: melting point of polymer composed of components constituting the hard segment). That is, the melting point (T) is preferably between TO-5 and TO-60, more preferably between TO-10 and TO-50, and even more preferably between TO-15 and TO-40. It is better to do so.

  Further, the melting point (T) is preferably 10 ° C. or more, preferably 20 ° C. or more higher than the melting point of the random copolymer. When the melting point of the random copolymer is not determined, the melting point (T) should be 150 ° C. or higher, preferably 160 ° C. or higher.

  When a random copolymer is used instead of the above polyester block copolymer, this polymer is generally amorphous and has a low glass transition temperature, so it is in a water tank shape, and the moldability is significantly reduced. The surface is not sticky and cannot be used as a real problem.

  The polyester block copolymer used in the present embodiment preferably has an intrinsic viscosity of 0.6 or more, more preferably 0.8 to 1.5, measured in 35 ° C. orthochlorophenol. If the intrinsic viscosity is lower than this, the strength is lowered, which is not preferable.

  The production method of the polyester block copolymer used in the present embodiment is to produce a polymer constituting the soft segment and the hard segment, respectively, and melt-mix them so that the melting point is lower than that of the polyester constituting the hard segment. A method is mentioned. Since this melting point varies depending on the mixing temperature and time, it is preferable to deactivate the catalyst by adding a catalyst deactivator such as phosphoric acid when the target melting point is reached.

  The polyester resin composition used for the outer layer 30 contains a hydrolysis inhibitor.

  Suitable hydrolysis inhibitors used in the embodiments of the present invention include compounds having a carbodiimide skeleton such as dicyclohexylcarbodiimide, diisopropylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride. However, it is not particularly limited.

  The addition amount of the hydrolysis inhibitor is 0.5 to 5 parts by mass, preferably 1 to 4 parts by mass, more preferably 2 to 4 parts by mass, and further preferably 2 to 100 parts by mass of the base polymer. ~ 3 parts by mass. This is because when the amount is less than 0.5 parts by mass, the hydrolysis resistance cannot be sufficiently exhibited, and when the amount added is more than 5 parts by mass, low toxicity cannot be achieved.

  The polyester-based resin composition used for the outer layer 30 includes an inorganic porous filler. The reason for adding the inorganic porous filler is to further improve the electrical characteristics of the outer layer 30.

  The addition amount of the inorganic porous filler is 0.5 to 5 parts by mass, preferably 0.5 to 3 parts by mass, more preferably 0.5 to 2 parts by mass with respect to 100 parts by mass of the base polymer. More preferably, it is 0.5 to 1 part by mass. If the content is too small, ions cannot be trapped sufficiently, the insulation resistance becomes small, and the electrical characteristics are inferior. On the other hand, if the content is too large, the wear resistance is undesirably lowered.

The inorganic porous filler used in the embodiment of the present invention preferably has a specific surface area of 5 m ² / g or more.

  The inorganic porous filler is preferably calcined clay, but is not limited thereto, and may be zeolite, mesalite, anthracite, pearlite foam, activated carbon, or may be surface treated with silane, fatty acid, or the like.

  The polyester resin composition used for the outer layer 30 includes magnesium hydroxide. The reason for adding magnesium hydroxide is to improve flame retardancy and to provide low smoke generation.

  The addition amount of magnesium hydroxide needs to be added in the range of 10 to 30 parts by mass with respect to 100 parts by mass of the base polymer. When the addition amount is less than 10 parts by mass, the flame retardancy and low smoke generation cannot be sufficiently exhibited. When the addition amount is more than 30 parts by mass, flexibility and wear resistance are obtained when the wire is processed. descend.

  Magnesium hydroxide used in the embodiment of the present invention is not particularly limited, and fatty acid, fatty acid metal salt, vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxy. Surface treatment may be performed with silane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, or the like, or an untreated product may be used.

  As a method of blending the above-mentioned various components into the polyester resin as the base polymer, it can be carried out by well-known means at any stage up to immediately before the coating step. As the simplest method, a method in which a polyester resin, a polyester block copolymer, a hydrolyzable inhibitor, an inorganic porous filler, magnesium hydroxide, and the like are pelletized by melt mixing extrusion is employed.

  As long as the effects of the present invention are exhibited, the resin composition used for the inner layer 20 and the outer layer 30 includes a pigment, a dye, a filler, a nucleating agent, a release agent, an antioxidant, a stabilizer, an antistatic agent, a lubricant, Other known additives can be blended and kneaded.

  In addition, as a manufacturing method of the multilayer insulated wire 1 which concerns on embodiment of this invention, the resin composition of the inner layer 20 and the resin composition of the outer layer 30 may be extrusion-coated by a separate process, and two layers are extrusion-coated simultaneously. May be. If necessary, the extrusion-coated multilayer insulated wire 1 may be irradiated and crosslinked.

  It is desirable that the insulation thickness of the insulated wire having a two-layer structure (inner layer 20 and outer layer 30) is 0.15 to 0.5 mm, and the inner layer 20 has a thickness of 0.05 to 0.2 mm. The thickness of the outer layer 30 is preferably 0.1 to 0.3 mm.

  The multilayer insulated wire 1 according to the embodiment of the present invention is not limited to two layers as long as the inner layer 20 and the outer layer 30 are provided. The conductor 10 and the inner layer 20 are not limited as long as the effects of the present invention are achieved. An insulating layer may be interposed between them, and an intermediate layer may be provided between the inner layer 20 and the outer layer 30.

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

The multilayer insulated wire which concerns on Examples 1-5, Comparative Examples 1-9, and the prior art example 1 was produced as follows. Table 1 shows the composition of the inner layer resin composition and the outer layer resin composition of the multilayer insulated wire, and Table 2 shows the evaluation results for each.
[Materials used]
HDPE (High Density Polyethylene): Prime Polymer Co., Ltd., Hi-Zex 550P (Hi-Zex is a registered trademark)
-EEA (ethylene ethyl acrylate copolymer): manufactured by Nippon Polyethylene Corporation, Lexpearl EEA A1150 (Lexpearl is a registered trademark) (ethyl acrylate content: 15% by mass)
・ PBN (polybutylene naphthalate resin): TQB-OT, manufactured by Teijin Chemicals Limited
・ PBT (polybutylene terephthalate resin): Mitsubishi Engineering Plastics, Nova Duran 5026 (Nova Duran is a registered trademark)
-PEBC (polyester block copolymer): manufactured by Teijin Chemicals Ltd., Nouvelan TRB-EL2 (Nouvelan is a registered trademark)
・ Hydrolysis inhibitor: (Polycarbodiimide) Nisshinbo Co., Ltd., Carbodilite HMV-8CA (Carbodilite is a registered trademark)
・ Calcined clay 1: (surface-treated calcined kaolin) manufactured by BASF, TRANSLINK 77
・ Calcined clay 2: (Surface-treated calcined kaolin) SATINTONE SP-33 (SATINTONE is a registered trademark) manufactured by Engelhard
Magnesium hydroxide: manufactured by Kyowa Chemical Industry Co., Ltd., Kisuma 5L (Kisuma is a registered trademark)

[Manufacture of multilayer insulated wires]
Regarding the obtained resin composition A and resin composition B, the resin composition A was dried at 80 ° C. for 8 hours or longer, the resin composition B was dried at 120 ° C. for 8 hours or longer in a hot air thermostat, and then the diameter was 1.2 mm. The resin composition A was extruded with a coating thickness of 0.15 mm directly onto the tin-plated annealed copper wire, and the resin composition B was extruded with a coating thickness of 0.10 mm on the outer periphery thereof. A multilayer insulated wire of a conventional example was produced. For extrusion molding, dies and nipples having a diameter of 4.2 mm and 2.0 mm were used, respectively, and the extrusion temperature was 220 ° C. to 270 ° C. for the cylinder portion and 265 ° C. for the head portion. The take-up speed was 10 m / min.

The abrasion resistance, hydrolysis resistance, flame resistance, heat resistance, low smoke generation, low toxicity, and insulation resistance at high temperatures were evaluated as follows.
[Abrasion resistance test]
A short circuit is performed by reciprocating the manufactured multilayer insulated wire 1 (mounted on the gantry 43) in a room temperature atmosphere while applying a load 9N with the wear needle 42 of the wear tester 40 shown in FIGS. The number of round trips was measured. The load was adjusted with the weight 41. The number of reciprocations of 150 times or more was accepted and less than 150 times was rejected.
[Hydrolysis resistance test]
The sample from which the conductor 10 of the produced multilayer insulated wire 1 was removed was allowed to stand for 30 days in a constant temperature and humidity chamber at 85 ° C./85% RH. Then, the winding test by a self-diameter was implemented, and the thing in which a crack does not generate | occur | produce was set as the pass ((circle)), and the thing in which a crack generate | occur | produced was set as the disqualified (x).
[Flame retardance test]
The produced multilayer insulated wire 1 was tested for flame retardancy in accordance with the IEC combustion test method (IEC603332-1). As shown in FIG. 3, the multilayer insulated wire 1 is vertically held by the upper support portion 1 a and the lower support portion 1 b, and the flame of the burner 50 is located at 475 ± 5 mm from the upper support portion 1 a with respect to the multilayer insulated wire 1. And after applying the flame for a specified burning time at an angle of 45 °, the burner 50 was removed, the flame was extinguished, and the carbonized portion 1c was examined.

Among the distances from the upper support part 1a to the carbonized part 1c, the distance to the upper part of the electric wire (α in FIG. 3) is 50 mm or more and the distance to the lower part of the electric wire (β in FIG. 3) is 540 mm or less. Anything other than the above range was regarded as rejected (x).
[Heat resistance test]
The heat resistance test was performed by performing the following heat aging treatment and then performing a tensile test to measure heat aging characteristics.

Heat aging treatment;
The sample from which the conductor 10 of the produced multilayer insulated wire 1 was removed was heat-treated at 150 ° C./96 h under a constant temperature bath and left at room temperature for about 12 hours. Heat treatment shall comply with JISC3005.

Heat aging characteristics;
A tensile test was performed on the sample after the heat aging treatment (measured at a tensile speed of 200 mm / min). The tensile test shall comply with JISC3005. An elongation residual ratio ((elongation before heat aging / elongation after heat aging) × 100) of 70% or more was evaluated as “O” (pass), and an elongation residual ratio of less than 70% was determined as “x” (fail).
[Fume concentration test]
According to EN50268.2, the change in transmittance due to smoke generated when the multilayer insulated wire 1 was burned was measured. A transmittance of 70% or more was accepted (◯), and a transmittance of less than 70% was rejected (x).
[Toxicity test]
In accordance with EN50305.9.2, the conductor 10 of the multi-layer insulated wire 1 is removed, the remaining inner layer 20 and outer layer 30 are cut into pieces, 1 g of the sample is burned at 800 ° C., and five types of gases (CO, CO ₂ , HCN) , SO ₂ , NOx) were quantitatively analyzed, and converted into toxicity index (ITC value) by a predetermined weighting and evaluated. An ITC value of 6 or less was accepted (◯), and an ITC value greater than 6 was rejected (x).
[Measurement of insulation resistance at high temperature]
According to EN50305.6.4, 15 m of multilayer insulated wires were immersed in warm water at 90 ° C. for 1 hour, and then measured at a measurement voltage of 80 to 500V. The measured value was converted into an insulation resistance per 1 km and evaluated. 600 MΩ / km or more was regarded as acceptable (◯), and less than 600 MΩ / km was regarded as unacceptable (x).
[Comprehensive judgment]
Abrasion resistance, hydrolysis resistance, flame retardancy, heat resistance, low smoke generation, low toxicity, high insulation resistance evaluation results at high temperatures are all acceptable (○), and any one or more Was rejected (x).

From Table 2, all of Examples 1 to 5 within the specified range of the present invention are wear resistance, hydrolysis resistance, flame resistance, heat resistance, low smoke generation, low toxicity, and insulation at high temperature. It turns out that it is excellent in resistance.

  On the other hand, in Comparative Example 1, since the inner layer material was only HDPE, the flame retardancy was unacceptable. In Comparative Example 2, since the amount of HDPE added was less than the specified range of the present invention, the wear resistance was unacceptable. In Comparative Example 3, since the inner layer material was only EEA, the wear resistance was not acceptable. In Comparative Example 4, since the amount of magnesium hydroxide added was larger than the specified range of the present invention, the abrasion resistance, hydrolysis resistance, and heat resistance (elongation characteristics after heat treatment) were unacceptable. Comparative Example 5 is rejected in terms of flame retardancy, low smoke generation, and low toxicity because the amount of magnesium hydroxide added is small. Since the comparative example 6 had much addition amount of the polyester block copolymer of outer-layer material, abrasion resistance failed. Since the comparative example 7 had few addition amounts of the polyester block copolymer, heat resistance (elongation characteristic after heat processing) was disqualified. Comparative Example 8 was rejected in terms of wear resistance and heat resistance (elongation characteristics after heat treatment) because of the large amount of the fired clay component of the outer layer material. Since the comparative example 9 had much addition amount of the hydrolysis-resistant inhibitor of outer-layer material, it was disqualified at the point of low toxicity.

  Moreover, in the prior art example 1 whose base polymer of an inner layer and an outer layer is polybutylene naphthalate (PBN), the insulation resistance at the time of low toxicity and high temperature was disqualified.

1: multilayer insulated wire, 10: conductor, 20: inner layer, 30: outer layer 40: wear tester, 41: weight, 42: wear needle, 43: mount 50: burner, 1a: upper support, 1b: lower support 1c: carbonization part

Claims (1)

In a non-halogen multilayer insulated wire comprising a conductor, an inner layer coated with a polyolefin-based resin composition on the conductor, and a coating layer comprising an outer layer coated with a polyester-based resin composition on the outside of the inner layer,
The coating layer is
A reciprocating operation is performed while applying a load of 9 N with a wear needle, and the number of reciprocations until a short circuit is 150 times or more,
Hydrolysis resistance in which cracks do not occur due to winding with a self-diameter after standing in an oven at 85 ° C./85% RH for 30 days,
After carrying out a combustion test in accordance with IEC603332-1, the distance from the upper support part to the carbonization part, the distance to the upper part of the electric wire is 50 mm or more and the distance to the lower part of the electric wire is 540 mm or less,
Heat resistance with an elongation percentage of 70% or more in a tensile test after heat treatment in accordance with JISC3005;
Low smoke emission with a smoke transmittance of 70% or more generated by a smoke concentration test according to EN50268.2,
Low toxicity with a toxicity index of 6 or less according to toxicity tests according to EN 50305.9.2,
A non-halogen multi-layer insulated wire characterized by having a high temperature insulation resistance of 600 MΩ / km or more according to EN50305.6.4.