JPH1153947A - Cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain airtightness and watertightness of an interface between a cable and a molded body over a long period of time by forming the outermost layer of a coating layer of a multiconductor stranded wire, of a cross-linked body of a resin composition containing as resin constituents, a specific rate of a thermoplastic polyester elastomer and a thermoplastic styrene elastomer. SOLUTION: A multi-conductor stranded wire 1 is formed by stranding a plurality of insulated conductors consisting of by providing an insulation layer 1b composed of a polyethylene resin composition, a polyvinylchloride resin composition, etc., on each of conductors 1a. A coating layer 2 for coating the multiconductor stranded wire 1 comprises a layer made up by appropriately cross-linking a resin composition containing, as resin constituents, 5 to 40 wt.% of a thermoplastic polyester elastomer and 5 to 40 wt.% of thermoplastic styrene elastomer. The adhesive property of a cable coating material to a molded material is very high at a cable end part, and the cable is resistant to high temperature and high pressure at the time of resin molding as well as heating and cooling at the time of use, due to being coated with a cross-linked body of a specific resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable used for automobiles, robots, electronic equipment, and the like. After being connected to the like, it is suitable to be molded with a thermoplastic resin such as a polybutylene terephthalate (hereinafter also referred to as PBT) resin or a polyamide (hereinafter also referred to as PA) resin in order to keep the connection portion airtight or watertight. It is about a simple cable.

[0002]

2. Description of the Related Art A thermoplastic polyurethane resin composition having good mechanical properties and flexibility is used as an insulating coating material for cables used for automobiles, robots, electronic devices and the like. After molding, the thermoplastic polyurethane resin composition is often improved in heat resistance, chemical resistance and water resistance by crosslinking treatment by irradiation with ionizing radiation. When connecting a component such as a sensor or an electrode terminal to such a cable, the connection portion and the periphery thereof are molded airtight or watertight with a resin mold (molded body) and protected. In order to secure airtightness and watertightness with a resin mold as described above, PBT resin and PA resin are often used as a molding material because of ease of molding and excellent mechanical strength.

[0003]

However, depending on the selection of the covering material and the molding material of the cable, the difference in the thermal shrinkage between the materials may cause the cable and the molded body to be heated and cooled during the terminal processing and the use. A gap is created at the interface,
There is a problem that moisture infiltrates from a gap generated at the interface. If moisture enters through the gaps created at the interface, the conductors of the cable will corrode and the performance of the connected equipment parts will deteriorate, and other problems will occur.Therefore, various sealing measures must be taken to maintain airtightness and watertightness. Required. For this reason, the workability at the time of terminal processing becomes extremely complicated, and the work required a high degree of skill.

In order to solve such a problem, it is conceivable that the covering material of the cable is made of the same or similar material as the molding material in consideration of adhesiveness with the molding material. The coating material has poor moldability and has a problem in the flexibility required for electric wires. In addition, even if the coating material has satisfactory initial adhesion to the molding material, air-tightness and water-tightness are impaired in the heat shock test, and materials that exhibit characteristic deterioration in the water resistance test are practical in the long term. Not a target. An object of the present invention is to maintain air-tightness and water-tightness of an interface between a cable and a molded body for a long period of time without taking special sealing measures to maintain air-tightness and water-tightness, and to provide a conductor for a cable. An object of the present invention is to provide a cable which can prevent corrosion and performance degradation of connected equipment parts and has excellent water resistance.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have combined an elastomer (having rubber-like elasticity at around normal temperature) as a resin component of a coating material. In other words, the use of a thermoplastic polyester elastomer that has little adhesion to the molding material alone and a thermoplastic styrene-based elastomer that has little adhesion to the molding material in combination with the molding material in a predetermined ratio allows the adhesion of the thermoplastic polyester elastomer alone The present inventors have found that an adhesiveness greatly exceeding that of the present invention can be obtained, and have completed the present invention. That is, in the present invention, (1) in a cable provided with a coating layer on the outside of a multi-core stranded wire in which a plurality of insulated conductors are twisted, at least the outermost layer of the coating layer is 5 to 40% by weight of a thermoplastic polyester elastomer. And a cable formed of a crosslinked product of a resin composition containing 5 to 40% by weight of a thermoplastic styrene-based elastomer as a resin component.
(2) When the resin composition is a resin component other than the thermoplastic polyester elastomer and the styrene-based thermoplastic elastomer, ethylene vinyl acetate / vinyl chloride graft copolymer, ethylene / glycidyl methacrylate copolymer, thermoplastic polyamide elastomer and heat (1) The cable according to (1), which contains at least one member selected from the group consisting of plastic polyurethanes, and (3) 0.5 to 0.5 parts by weight of fine particle silica based on 100 parts by weight of the total amount of the resin components in the resin composition. The cable according to (1) or (2), which comprises 5 parts by weight, (4) the coating layer is composed of two layers, and ethylene vinyl acetate
At least one selected from the group consisting of a vinyl chloride graft copolymer, a thermoplastic polyamide elastomer, a thermoplastic polyester elastomer, and a thermoplastic polyurethane;
The cable according to any one of (1) to (3), wherein a resin composition having a seed as a base resin is used.
(5) The coating layer is composed of two layers, and the inner layer is selected from the group consisting of an ethylene / α-olefin copolymer and an ethylene / vinyl acetate copolymer having a density of 0.86 to 0.90 g / cm ³ . The cable according to any one of (1) to (3), wherein a resin composition using at least one type of base resin is provided.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the cable of the present invention, one or more coating layers may be provided on a multifilamentary stranded wire obtained by twisting insulated conductors. When a plurality of layers are formed, they may be coated by simultaneous extrusion, or the next outer layer may be sequentially coated after the inner layer is coated. In this case, at least the outermost layer of the coating layer comprises 5 to 40% by weight of the thermoplastic polyester elastomer, and (b) 5 to 5% of the thermoplastic styrene elastomer.
It is formed of a resin composition containing 40% by weight as a resin component.

An embodiment of the present invention will be described below. FIG. 1 is a schematic sectional view showing an embodiment of a cable according to the present invention, wherein 1 is a multi-core stranded wire, and the multi-core stranded wire 1 is a conductor (for example, 20 tinned soft copper wires having an outer diameter of 0.18 mmφ are stranded). A plurality of insulated conductors (2 in FIG. 1) provided with an insulating layer 1b made of a polyethylene resin composition, a polyvinyl chloride resin composition, etc. on a stranded wire conductor 1a having a conductor diameter of 1 mmφ.
Book). 2 is multi-core stranded wire 1
The coating layer 2 is a layer formed by appropriately cross-linking a resin composition containing the thermoplastic polyester elastomer and the thermoplastic styrene-based elastomer as a resin component. The coating layer provided on the outer side of the multi-core stranded wire is preferably a multilayer of two or more layers in order to enhance the roundness of the cable cross section. FIG. A plurality of coating layers 2 (FIG. 2)
In this case, the inner layer 2a is made of at least one selected from the group consisting of ethylene vinyl acetate / vinyl chloride graft copolymer, thermoplastic polyamide elastomer, thermoplastic polyester elastomer, and thermoplastic polyurethane. And a base resin comprising at least one selected from the group consisting of ethylene / α-olefin copolymer and ethylene / vinyl acetate copolymer having a density of 0.86 to 0.90 g / cm ^3. It can be formed with a resin composition. This inner layer may be an appropriately crosslinked layer.

The outer layer 2b of the coating layer is composed of a layer obtained by appropriately crosslinking a resin composition containing the above-mentioned thermoplastic polyester elastomer and thermoplastic styrene-based elastomer as a resin component. In the cable of the present invention, since the outermost layer of the coating layer provided on the multifilamentary stranded wire is formed by a crosslinked body of a specific resin composition, the cable coating material and the molding material (molded body) at the cable end portion Air-tightness and water-tightness at the interface between the cable and the molding material (molded product), which results in high temperature and high pressure during resin molding at the end of the cable, or as a result of repeated heating and cooling during use. The problem of failure is solved. The resin composition constituting at least the outermost layer of the coating layer of the cable of the present invention contains a thermoplastic polyester elastomer and a thermoplastic styrene-based elastomer as resin components. The thermoplastic polyester elastomer used in the present invention is a block copolymer of a hard segment composed of an aromatic polyester such as polybutylene terephthalate and polybutylene isophthalate and a soft segment composed of an aliphatic polyether such as polytetramethylene ether glycol. It is united. As such a thermoplastic polyester elastomer,
For example, “Hytrel” (trade name, manufactured by Toray Dupont), “Perprene” (trade name, manufactured by Toyobo Co., Ltd.) and the like are commercially available, and can be appropriately selected from various grades of commercially available products.

As the thermoplastic styrene elastomer used in the present invention, an SB block copolymer composed of styrene (S) and butadiene (B) or an unsaturated double bond in those butadiene blocks is obtained by hydrogenation. SEP comprising saturated SEB-based block copolymer, styrene (S) and ethylene-propylene (EP)
Block copolymers, etc. In addition, SEB in which the terminal portion of a random copolymer of styrene (S) and butadiene (B) is a styrene block and hydrogenated from the styrene block
A system block copolymer can also be used.
Further, for the purpose of improving the compatibility, it is also possible to use those obtained by modifying these copolymers with unsaturated carboxylic acids such as maleic anhydride and glycidyl methacrylate and derivatives thereof. As such,
"Clayton" (trade name, manufactured by Shell Chemical Co., Ltd.), "Tufprene", "Asaprene", "Tuftec" (trade name, manufactured by Asahi Kasei), "Septon" (trade name, manufactured by Kuraray), "Dynalon" (trade name, (Nippon Synthetic Rubber Co., Ltd.) is commercially available and can be appropriately selected from various grades of commercially available products. Among these styrene-based thermoplastic elastomers, SEP-based ones are preferable from the viewpoint of weather resistance, and in particular, use of a grade having excellent flexibility is preferable.
The thermoplastic styrene-based elastomer used in the present invention by itself has almost no adhesion to injection molding materials such as PBT resin and polyamide resin. However,
By using in combination with the thermoplastic polyester elastomer in a predetermined ratio, surprising adhesion,
Moreover, its adhesiveness is far greater than the adhesive strength of a thermoplastic polyester elastomer alone to a molding material.

The amounts of the thermoplastic polyester elastomer and the thermoplastic styrene elastomer which are the resin components in the resin composition constituting at least the outermost layer of the coating layer of the cable of the present invention will be described. The blending amount of the thermoplastic polyester elastomer is in the range of 5 to 40% by weight, preferably 10 to 35% by weight. When the blending amount of the thermoplastic polyelastomer is within this range, the adhesiveness between the outermost layer of the cable and the molding material is good, and not only water tightness and air tightness can be ensured, but also good water resistance. The blending amount of the thermoplastic styrene-based elastomer is in the range of 5 to 40% by weight, preferably 10 to 35% by weight. If the compounding amount exceeds 40% by weight, the adhesive strength between the outermost layer of the cable and the molding material such as PBT resin or PA resin is improved,
There is a problem that the wear resistance is significantly reduced. On the other hand, if the blending amount is less than 5% by weight, the adhesive strength between the outermost layer of the cable and the molding material is almost the same as when the thermoplastic styrene elastomer is not blended.

The resin composition may be blended with other resin components that provide the required performance of the cable such as abrasion resistance, as long as the properties of the thermoplastic polyester elastomer and the thermoplastic styrene elastomer are not impaired. it can. In particular, in order to compensate for the decrease in wear resistance due to the thermoplastic styrene-based elastomer, ethylene-vinyl acetate-vinyl chloride graft copolymer, ethylene-
It is preferable to mix any one of a glycidyl methacrylate copolymer, a thermoplastic polyamide elastomer, and a thermoplastic polyurethane, or a mixture thereof. The ethylene vinyl acetate / vinyl chloride graft copolymer has a structure in which the ethylene vinyl acetate copolymer is a trunk polymer and vinyl chloride is a branch polymer, and the hardness can be changed by the ratio of the ethylene vinyl acetate copolymer. . As such an ethylene vinyl acetate / vinyl chloride graft copolymer, for example, “ZESTGR” (trade name, manufactured by Shin-Daiichi Chloride) is commercially available. Examples of the ethylene / glycidyl methacrylate copolymer include an ethylene / glycidyl methacrylate copolymer, an ethylene / glycidyl methacrylate / vinyl acetate terpolymer, and an ethylene / glycidyl methacrylate copolymer.
Glycidyl methacrylate / methyl acrylate terpolymer is exemplified. As such, “Bond First” (trade name, manufactured by Sumitomo Chemical Co., Ltd.) is commercially available. The thermoplastic polyamide elastomer is a block copolymer in which nylon 6, nylon 12, and the like are used as hard segments, and polytetramethylene ether glycol, polypropylene glycol, and the like are used as soft segments. As such thermoplastic polyamide elastomer, for example, “Daiamide” (trade name, manufactured by Daicel Huls), “Pebax” (trade name, manufactured by Toray Industries) and the like are commercially available. It can be appropriately selected and used. Examples of the thermoplastic polyurethane include polyester-based urethanes (adipate-based, caprolactone-based, and polycarbonate-based) and polyether-based urethanes. Polyether-based urethanes are preferable in terms of water resistance, mold resistance, and the like.

Further, by blending fine particle silica as an additive, the abrasion resistance of the resin composition can be improved. Regarding the particulate silica, any of a dry method and a wet method can be used regardless of the production method. Examples of such products include “Aerosil” (trade name, manufactured by Nippon Aerosil Co., Ltd.) and “Toksil” (trade name,
Tokuyama Soda Co., Ltd.) is commercially available. The compounding amount of the fine particle silica is 0.5 with respect to 100 parts by weight of the total amount of the resin component.
-5 parts by weight, and exceeding 5 parts by weight is not preferable because the cold resistance of the cable is reduced. The coating layer provided on the outside of the multi-core stranded wire is used to improve the roundness of the cable cross section.
It is preferable to use a multilayer having at least two layers. Among the multilayer coating layers, the coating material for the inner layer is selected in consideration of the adhesiveness to the outermost coating layer, and is particularly selected from an ethylene vinyl acetate / vinyl chloride graft copolymer, a thermoplastic polyamide elastomer, and a thermoplastic polyamide elastomer. A resin composition containing any one of a polyester elastomer and a thermoplastic polyurethane or a mixture thereof as a base resin, or having a density of 0.86 to 0.90.
A resin composition containing, as a base resin, one of an ethylene / α-olefin copolymer and an ethylene / vinyl acetate copolymer having a g / cm ³ or a mixture thereof is preferred.

When a resin composition containing any one of ethylene vinyl acetate / vinyl chloride graft copolymer, thermoplastic polyamide elastomer, thermoplastic polyester elastomer, thermoplastic polyurethane or a mixture thereof as a base resin is used as an inner layer coating material. In addition to maintaining airtightness and repeated bending characteristics between the inner layer and the outer layer, stripping of the sheath at the time of processing the cable becomes easy. In addition, as a coating material for the inner layer, the density is 0.86 to
When a resin composition having a base resin of at least one selected from the group consisting of an ethylene / α-olefin copolymer and an ethylene / vinyl acetate copolymer having a weight of 0.90 g / cm ³ is used as the inner layer coating material. In addition, it is possible to form a cable at low cost while maintaining airtightness and repetitive bending characteristics between the inner layer and the outer layer. The ethylene / α-olefin copolymer includes ethylene and propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene,
-Decene, a copolymer with at least one kind of α-olefin such as 1-dodecene, and from the viewpoint of crosslinkability and elasticity,
In the present invention, the density is 0.86 to 0.90 g / cm ^3.
The ethylene-vinyl acetate copolymer has a vinyl acetate content of 10 from the viewpoint of crosslinkability and elasticity.
-30% by weight is preferred. The ethylene / α-olefin copolymer and the ethylene / vinyl acetate copolymer can be used alone or as a mixture of both.

The heat resistance of the resin composition constituting the inner layer can be improved by cross-linking. When the resin composition is molded with a resin having a high melting point, such as polybutylene terephthalate or polyamide, it is preferable to cross-link the resin composition. Heat resistance and rubber elasticity can be improved by crosslinking the coating layer,
As a result, the elastic repulsive force of the cable insulating layer, that is, the restoring force is improved, so that the air-tightness and the water-tightness of the interface with the molded body molded into the terminal are improved. As a method for cross-linking the coating layer, a conventionally known cross-linking method using ionizing radiation or a chemical cross-linking method can be employed, but from the viewpoint of productivity, a cross-linking method using irradiation with ionizing radiation such as an electron beam is preferable. The dose of the electron beam is suitably from 1 to 30 Mrad. In the case of the chemical crosslinking method, a resin composition containing an organic peroxide as a crosslinking agent is used, and the crosslinking is completed by heat treatment after extrusion molding. The resin composition used for the outermost layer of the coating layer can further improve heat resistance, chemical resistance, and water resistance by being appropriately crosslinked, but the gel fraction is 5 to 5.
At 0%, the improvement in adhesiveness and heat resistance is most recognized.
If it is less than 5%, the effect of crosslinking such as melting of the cable coating layer in a high temperature atmosphere of 200 ° C. or higher is not recognized. 5
If it exceeds 0%, the adhesiveness, which is the object of the present invention, is reduced, resulting in impaired airtightness and watertightness.

The resin composition constituting the coating layer of the cable according to the present invention contains various additives generally used in insulated wires and cables, such as antioxidants, metal deactivators, and flame retardants. , Dispersants, colorants, fillers,
A lubricant and the like can be appropriately compounded within a range that does not impair the purpose of the present invention. In particular, the addition of a flame retardant is indispensable for automotive applications.

As antioxidants, 4,4'-dioctyl diphenylamine, N, N'-diphenyl-p-phenylenediamine, 2,2,4-trimethyl-1,2-
Amine-based antioxidants such as dihydroquinoline polymers, pentaerythrityl-tetrakis (3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propione-
G), octadecyl-3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionate, 1,3,5
-Trimethyl-2,4,6-tris (3,5-di-t-
Phenolic antioxidants such as butyl-4-hydroxybenzyl) benzene, bis (2-methyl-4- (3-n-
Alkylthiopropionyloxy) -5-t-butylphenyl) sulfide, 2-mercaptobenzimidazo-
And zinc salts thereof, and sulfur-based antioxidants such as pentaerythritol-tetrakis (3-lauryl-thiopropionate).

Examples of the metal deactivator include N, N'-bis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1, 2,4-triazole, 2, 2'-
Oxamidobis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like.

As the flame retardant, tetrabromobisphenol A (TBA), decabromodiphenyl oxide (DBDPO), octabromodiphenyl ether (O
BDPE), hexabromocyclododecane (HBC
D), bistribromophenoxyethane (BTBP)
E), halogen-based flame retardants such as tribromophenol (TBP), ethylenebistetrabromophthalimide, TBA / polycarbonate oligomer, brominated polystyrene, brominated epoxy, ethylenebispentabromodiphenyl, chlorinated paraffin, dodecachlorocyclooctane, etc. And inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide, and phosphorus-based flame retardants such as phosphoric acid compounds, polyphosphoric acid compounds and red phosphorus compounds.

Examples of the flame retardant aid and filler include carbon, clay, zinc oxide, tin oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silica, talc, calcium carbonate, magnesium carbonate, zinc borate and the like.

[0020]

Next, the present invention will be described in more detail with reference to examples. (Examples 1 to 10, Comparative Examples 1 to 3) Conductor (conductor diameter 1 mm
φ tinned soft copper stranded wire Composition: 20 / 0.18mm
On top of φ), low-density polyethylene was extrusion-coated to an outer diameter of 1.7 mm, and irradiated with an electron beam having an acceleration voltage of 500 keV and a dose of 20 Mrad to obtain an insulated conductor having a cross-linked polyethylene insulating layer. A multi-core stranded wire was prepared by twisting two of these insulated conductors. Then, using a 40 mmφ extruder (L / D = 25) on the multi-core stranded wire, a die temperature of 180 ° C., and then to a feeder side, C3 = 170 ° C.
According to the conditions of C2 = 160 ° C. and C1 = 150 ° C., any one of (A) thermoplastic polyurethane, (B) ethylene-vinyl acetate copolymer, and (C) ethylene / α-olefin copolymer shown in the table Was extruded to an outer diameter of 4.2 mm to form an inner coating layer. Further, the outer resin composition shown in Table 2 was further coated with the outer layer of the same composition as the inner layer so that the outer diameter was 5.0 mm. Extrusion coated under conditions. Next, after extrusion coating, the coating layer was cross-linked by irradiating an electron beam with an acceleration voltage of 750 keV and the irradiation dose shown in the table, to obtain a cable having two coating layers as shown in FIG. For each of the obtained cables, various characteristics were evaluated by the following test methods, and the results are also shown in Tables 1 to 3.

1) Gel Fraction of Outer Layer Only the outer layer was sampled from the cable, and was heated at 110 ° C. with xylene.
Extract for 24 hours, dry thoroughly and weigh. The weight remaining after melting was defined as a gel content and expressed as a percentage of the weight before solvent extraction.

2) Peel strength from PBT resin or PA resin and presence or absence of residue after peeling a) A coating layer of a cable having a predetermined length is divided into two in the longitudinal direction,
The insulated conductor is removed, b) the divided semicircular coating layer is set in a mold, and c) PBT resin or P
A resin (nylon 12) was injected to perform resin molding on the coating layer. The obtained resin molded body was subjected to a peel test. In the peeling test, the cable coating layer was peeled off from the resin molded body at an angle of 90 degrees at a rate of 50 mm / min, and the maximum strength at that time was measured. It was observed whether it was. When the coating material was destroyed by cohesive force and remained on the surface of the molded product, the result was evaluated as “O”.

3) Airtightness of Terminal As shown in FIG. 3, the covering layers 2 and 1b of the cable were removed to expose the conductor 1a, and the electrode terminal 5 was connected to the end. Next, the connection portion and the vicinity thereof were covered with a resin molded body 4 by molding (injection molding) using PBT resin. About this cable, 120 degreeC x 1 hour, -40
C. × 1 hour as one cycle, 100 cycles, 50 cycles
Perform a 0 cycle heat shock test, then
Compressed air of 2 atm was injected from the terminal opposite to the resin molded body side, immersed in water to check for leakage from the resin molded body side, and airtightness was confirmed by the presence or absence of bubbles. The test was carried out on 5 samples, and when all passed, it was evaluated as ○, and when any of the samples failed, it was evaluated as x.

4) Water resistance From the cable sample, only the outer skin was cut in half and collected.
I punched it with an 8-inch dumbbell. The punched sample is polished to a smooth surface, and then immersed in hot water at 90 ° C.
Dipped for 0 hours. The immersed sample was subjected to a tensile test using a constant-speed tensile tester at a distance of 20 mm between the marked lines and at a tensile speed of 500 mm / min, and the tensile strength at break (TS) and the elongation at break (El.) Were measured. This result was taken as T.P. S. , El. Expressed as a percentage.

5) Airtightness after immersion The sample before the heat shock test prepared in 3) was immersed in hot water under the same conditions as in 4), and then subjected to the same airtightness test as in 3). The number of tests was 3, and was evaluated as ○ when all the samples passed, and × when at least one of them failed.

6) Heat resistance A metal rod having the same diameter (5.0 mmφ) as the cable sample
It was left at 200 ° C. for 30 minutes while being wound for more than one turn.
After being taken out and sufficiently cooled at room temperature, it was visually confirmed that there was no crack or melting on the cable surface. Perform a three-sample test, and if all samples have no melting or cracks,
When at least one of them had melted or cracked, it was evaluated as x.

7) Abrasion Resistance A 600 gf load 11 is applied to the cable sample 10 fixed and supported by using an apparatus as shown in FIG. 4, and a roller 12 (diameter 7 mm) set on the opposite side to the load is applied. Wear tape 13 (150G wear tape)
After moving the cable sample 10 by 3 mm at 0 mm / min, the outer diameter of the cable sample 10 was measured.
mm or less was evaluated as ○, and when it exceeded 0.4 mm as ×.

The following components were used as the components shown in Tables 1 to 3. (01) TPEE (Thermoplastic polyester elastomer) manufactured by Toray Dupont Co., Ltd., trade name: Hytrel 2300X
06 (02) SEPS (thermoplastic styrene-based elastomer (SEP-based)) Kuraray Co., Ltd., trade name: Septon 2007 (03) HSBR (thermoplastic styrene-based elastomer (SEB-based)) Nippon Synthetic Rubber Co., Ltd. Trade name: Dynaron 1320P (04) EVA-VC (ethylene vinyl acetate / vinyl chloride graft copolymer) manufactured by Shin-Daiichi Vinyl Co., Ltd. Trade name: ZEST GR5FL (05) E-GMA (ethylene-glycidyl methacrylate copolymer) Combined product) Sumitomo Chemical Co., Ltd., trade name: Bond First E (06) TPAE (thermoplastic polyamide elastomer) Toray Co., Ltd., trade name: Pebax 3533 (07) TPU (thermoplastic polyurethane) Nippon Milactran Co., Ltd. Product name: E-385PNA
T (08) pentaerythrityl-tetrakis (3- (3,3
5-Di-t-butyl-4-hydroxyphenyl) propionate) Ciba Geigy Co., Ltd., trade name: Irganox 101
0 (09) Ethylenebispentabromodiphenyl Albemarle Co., Ltd., trade name: Cytex 8010 (10) Antimony trioxide, tin mine mining bureau, trade name: Shensei (11) Fine particle silica Nippon Aerosil Co., Ltd. Product name: Aerosil 200 (A) Thermoplastic polyurethane Product name: E-385PNA, manufactured by Nippon Milactran Co., Ltd.
T (B) Ethylene-vinyl acetate copolymer Mitsui-Dupont Polychemical Co., Ltd., trade name: Evaflex V527-4 (C) Ethylene / α-olefin copolymer Dow Chemical Co., Ltd., trade name: Engage CL8
003

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

[Table 3]

* Comparative Example 1 Gel fraction [%] of outer layer 0 Since TPU is insoluble in xylene, the gel fraction was determined using dimethylformamide.

From the results in Tables 1 and 2, the outermost layer of the coating layer was a crosslinked product of a resin composition containing 5 to 40% by weight of a thermoplastic polyester elastomer and 5 to 40% by weight of a thermoplastic styrene elastomer as a resin component. It can be seen that the formed cable of the example of the present invention has excellent adhesion between the cable covering material and the molded article, maintains the airtightness of the cable end, and has sufficient water resistance. On the other hand, as can be seen from the results of Comparative Examples shown in Table 3, in Comparative Example 3 in which the thermoplastic styrene-based elastomer is out of the range specified in the present invention, the PBT resin and P
Despite having sufficient adhesion to resin A, there is a problem that abrasion resistance is reduced, which is not preferable as the cable of the present invention intended for use in automobiles, robots, electronic devices, and the like. Further, when the amount is smaller than the specified range, that is, in Comparative Example 2 in which only the thermoplastic polyester elastomer is used as the resin component, since the adhesive force with the molding material is not as high as in the example, airtightness as an initial characteristic can be obtained. However, when the number of cycles of the heat shock test is increased, not only the airtightness is lost, but also the water resistance is extremely poor, and the airtightness cannot be maintained after immersion in hot water.

[0034]

The cable of the present invention is formed of a resin composition containing 5 to 40% by weight of a thermoplastic polyester elastomer and 5 to 40% by weight of a thermoplastic styrene-based elastomer as a resin component. When the terminal portion is molded with a thermoplastic resin such as PBT resin or PA resin, the cable coating material and the molding material are firmly adhered to each other, and even if no special sealing measures are taken, the interface between the cable and the molded body can be obtained. The airtightness and the watertightness are maintained for a long time, and the corrosion of the conductor of the insulated wire inside the cable and the deterioration of the performance of the connected device parts can be prevented. Furthermore, the cable of the present invention has extremely excellent water resistance, heat resistance,
Since a coating material having excellent extrusion characteristics is employed, it can be used for a long time as a wiring cable for automobiles, robots, electronic devices, and the like.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a cable according to the present invention.

FIG. 2 is a sectional view showing another embodiment of the cable of the present invention.

FIG. 3 is an explanatory view of an airtightness test of a cable terminal portion performed in Examples and Comparative Examples.

FIG. 4 is an explanatory diagram of a wear resistance evaluation device used in Examples and Comparative Examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Multi-core stranded wire 1a Conductor 1b Insulating layer 2 Coating layer 2a Inner layer 2b Outer layer 3 Cable 4 Resin molding 5 Electrode terminal

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H01B 7/18 H01B 7/18 H (72) Inventor Ryoji Ohno 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Inside the corporation

Claims (5)

[Claims] 1. A cable having a coating layer provided on the outside of a multifilamentary stranded wire in which a plurality of insulated conductors are twisted, wherein at least the outermost layer of the coating layer is 5 to 40% by weight of a thermoplastic polyester elastomer and a thermoplastic styrene-based material. A cable comprising a crosslinked product of a resin composition containing 5 to 40% by weight of an elastomer as a resin component. 2. The resin composition as a resin component other than the thermoplastic polyester elastomer and the styrene thermoplastic elastomer, ethylene vinyl acetate / vinyl chloride graft copolymer, ethylene / glycidyl methacrylate copolymer, thermoplastic polyamide elastomer The cable according to claim 1, further comprising at least one selected from the group consisting of thermoplastic polyurethane and thermoplastic polyurethane. 3. The cable according to claim 1, wherein the resin composition contains 0.5 to 5 parts by weight of particulate silica based on 100 parts by weight of the total amount of the resin component. 4. The coating layer is composed of two layers and at least one selected from the group consisting of an ethylene vinyl acetate / vinyl chloride graft copolymer, a thermoplastic polyamide elastomer, a thermoplastic polyester elastomer, and a thermoplastic polyurethane. The cable according to any one of claims 1 to 3, wherein a resin composition comprising: a base resin is used. 5. The coating layer is composed of two layers, and the inner layer has an ethylene · density of 0.86 to 0.90 g / cm ^3.
The resin composition according to any one of claims 1 to 3, wherein a resin composition comprising at least one selected from the group consisting of an α-olefin copolymer and an ethylene / vinyl acetate copolymer is used as a base resin. Cable.