JP2000030535A - Wire and cable covered with fluorine containing elastomer and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively suppress the producing of die residues at an extrusion molding process for covering a wire and cable, ensure an obtained cover layer free from an adverse effect on work environment even at a terminal processing work, and keep high heat resistance, flexibility, mechanical characteristics, cut-through resistance or the like. SOLUTION: This cable is constituted so that a fluorine contained elastomer cover layer 3 is formed on a conductor 1 or on the external surface of a cable core. In this case, the fluorine contained elastomer cover layer 3 is formed out of an inner cover layer 21 made of a fluorine contained elastomer blend formed by adding 5 to 200 pts.wt. of calcium carbonate for 100 pts.wt. of a blend composed of tetrafluoroethylene-propylene copolymer/polyvinylidene fluoride =50/50 to 95/5 by a weight ratio, and an outer cover layer 22 made of tetrafluoroethylene-propylene copolymer/ethylene-tetrafluoroethylene copolymer=50/50 to 95/5 blend by a weight ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorine-containing elastomer-coated electric wire / cable and a method for producing the same.

[0002]

2. Description of the Related Art Insulated electric wires used as lead wires of heating appliances for household appliances, for example, irons, electric rice cookers, microwave ovens, etc., require not only excellent heat resistance but also flexibility, mechanical properties, flame retardancy and the like. Is done.

Conventionally, as an insulated wire satisfying these characteristics, a glass thread braided silicone rubber covered wire, an asbestos glass tape reinforced silicone rubber covered wire, a tetrafluoroethylene resin covered wire and the like have been used.

[0004]

However, the above-mentioned insulated wires have the following disadvantages.

[0005] (1) Glass thread braided silicone rubber-coated electric wire When the glass thread braided silicone rubber-coated electric wire is subjected to terminal processing, the glass thread of the braid layer is scattered, and the scattered glass thread is applied to the skin of the terminal processing worker. There is a problem that the working environment such as stab is deteriorated.

(2) Asbestos glass tape-reinforced silicone rubber-coated electric wire Asbestos glass tape-reinforced silicone rubber-coated electric wire also has asbestos fibers and glass thread of the asbestos glass tape scattered during terminal processing. There is a problem that the working environment is deteriorated such that the glass thread enters the body from inside the nose of the terminal processing operator or pierces the skin.

(3) Tetrafluoroethylene resin-coated electric wire Since the tetrafluoroethylene resin is a resin having essentially high rigidity, the tetrafluoroethylene resin-coated electric wire formed by coating it has high rigidity, and therefore has high flexibility. There is a drawback that bendability, handleability and the like are poor.

On the other hand, the tetrafluoroethylene-propylene copolymer and polyvinylidene fluoride have poor compatibility, and as a result, die squeezing occurs during extrusion coating.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to effectively suppress the occurrence of die scabs during extrusion coating work. The obtained coating layer does not deteriorate the working environment even when the terminal processing work is performed, and also has heat resistance,
An object of the present invention is to provide a fluorine-containing elastomer-coated electric wire / cable excellent in flexibility, mechanical properties, cut-through resistance and the like, and a method for producing the same.

[0010]

The gist of the present invention is to provide a fluoroelastomer-coated cable having a fluoroelastomer coating layer provided on a conductor or on the outer periphery of a cable core, wherein the fluoroelastomer coating layer has a weight. In a ratio of tetrafluoroethylene-propylene copolymer / polyvinylidene fluoride = 50 / 50-95 / 5 100 parts by weight of the blend, 5-20 calcium carbonate
0 parts by weight of an inner coating layer comprising a fluorine-containing elastomer blend, and a tetrafluoroethylene-propylene copolymer / ethylene-tetrafluoroethylene copolymer = 50 / 50-95 / 5 blend by weight ratio A fluoroelastomer-coated electric wire / cable characterized by comprising an outer coating layer made of a material, and a fluoroelastomer-coated electric wire / cable characterized by simultaneously extruding and coating the above inner coating layer and the outer coating layer Manufacturing method.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a fluorine-containing elastomer-coated electric wire / cable of the present invention and a method of manufacturing the same will be described.

In the present invention, tetrafluoroethylene-
As the propylene copolymer, a copolymer composed of tetrafluoroethylene and propylene, or a copolymer of tetrafluoroethylene, propylene and another copolymerizable component can be used.

[0013] Such copolymerizable components include ethylene, butene-1, isobutene, acrylic acid, various esters of acrylic acid, methacrylic acid, various alkyl esters of methacrylic acid, vinyl fluoride, vinylidene fluoride,
Examples include hexafluoropropene, chloroethyl vinyl ether, glycidyl vinyl ether, chlorotrifluoroethylene, and perfluoroalkyl vinyl ether.

The tetrafluoroethylene-propylene copolymer has a molar ratio of tetrafluoroethylene / propylene of 95 from the viewpoint of heat resistance, moldability and the like.
It is desirable to select from the range of / 5 to 30/70, and a particularly preferred range is 90/10 to 45/55.

In the copolymer with tetrafluoroethylene, propylene and other copolymerizable components, the content of the copolymerizable component is 50 mol% or less, particularly preferably 30 mol% or less.

In the present invention, the fluorine-containing elastomer blend is obtained by blending polyvinylidene fluoride with tetrafluoroethylene-propylene, wherein the weight ratio of tetrafluoroethylene-propylene / polyvinylidene fluoride is 50/50 to 95/95. The reason for setting to 5 is as follows. That is, when the weight ratio of tetrafluoroethylene-propylene is 50% or less, the flexibility and elongation characteristics are deteriorated, and when the weight ratio of tetrafluoroethylene-propylene is 95% or more, the mechanical strength is reduced.

In the present invention, the fluoroelastomer blend is prepared by mixing a tetrafluoroethylene-propylene copolymer with polyvinylidene fluoride at a weight ratio of 50/50 to 50/50.
This is a fluoroelastomer blend obtained by adding 5-200 parts by weight of calcium carbonate to 100 parts by weight of a 95/5 blend.

Here, if calcium carbonate is less than 5 parts by weight, the effect of improving cut-through resistance is not seen, and if it is more than 200 parts by weight, tensile strength and elongation characteristics are sharply deteriorated. The preferred range of calcium carbonate is 40 to 150 parts by weight.

In the present invention, the calcium carbonate may be surface-treated with silica, vinyl silane, amino silane, fatty acid metal salt or the like.

In the present invention, calcium carbonate includes
Those having an average particle size of φ2.0 μm or less are suitable from the viewpoint of dispersibility and dielectric breakdown voltage. This preferred range is φ0.
4 to 1.0 μm.

In the present invention, the outer coating layer is made of a tetrafluoroethylene-propylene copolymer / ethylene-tetrafluoroethylene copolymer = 50 / 50-95 / 5 blend because the tetrafluoroethylene-propylene copolymer is used. When the amount of the polymer is less than 50 parts by weight, flexibility and heat resistance are inferior. On the other hand, when the amount of the tetrafluoroethylene-propylene copolymer is more than 95 parts by weight, there is a problem that the cut-through resistance is lowered and the tackiness is generated. Fluoro-elastomer-coated wires and cables having high adhesiveness may cause mutual adhesion, that is, blocking failure when bundled.

The outer coating layer was made of a blend of tetrafluoroethylene-propylene copolymer / ethylene-tetrafluoroethylene copolymer = 50 / 50-95 / 5.
By blending 5 to 150 parts by weight of calcium carbonate with respect to 00 parts by weight, cut-through resistance can be improved. The preferred amount of calcium carbonate is 20 to 8
0 parts by weight.

Calcium carbonate may be surface-treated with silica, vinyl silane, amino silane, fatty acid metal salt or the like as in the case of the inner coating layer. Similarly, calcium carbonate having an average particle size of φ2.0 μm or less is suitable from the viewpoint of dispersibility and dielectric breakdown voltage. This preferred range is φ0.4 to 1.0 μm.

In the present invention, in addition to these components, if necessary, other components such as a crosslinking monomer, a crosslinking agent, a crosslinking aid, a pigment, a lubricant, a processing aid, a stabilizer, an antioxidant and the like may be blended. Is also good.

[0025]

Next, examples and comparative examples of a fluorine-containing elastomer-coated electric wire / cable of the present invention and a method for producing the same will be described.

The fluorinated elastomer-coated electric wires and cables of the examples and the fluorinated elastomer-coated electric wires and cables of the comparative examples were prepared as follows.

[Weighting and Sampling of Base Material] First, the materials of Examples 1 to 5 and Comparative Examples 1 to 7 were weighed and collected according to the composition table of Table 1.

[0028]

[Table 1]

[Preparation of Pellet] Next, the base materials of Examples 1 to 5 and Comparative Examples 1 to 7 which were weighed and collected were kneaded at 200 ° C. in a small laboratory mixer.

Next, the kneaded material was roll-kneaded at 50 to 60 ° C. with an open roll, and then pulled out into a sheet.

Next, these sheets were pelletized by a pelletizer to obtain pellets of the fluorine-containing elastomer blends of Examples 1 to 5 and Comparative Examples 1 to 7.

[Extrusion coating of electric wires and cables] The extrusion coating of electric wires and cables was performed by tandemly arranging two extruders, a main extruder and a sub-extruder.

Here, the main extruder is a 40 mm main extruder in which the temperature of the cylinder 1 is 100 ° C., the temperature of the cylinder 2 (head) is 200 ° C., and L / D = 22.

The temperature of the cylinder 1 is 100 ° C., the temperature of the cylinder 2 (head) is 270 ° C.
A 40 mm sub-extruder with L / D = 22.

First, a cross-sectional area of 0.75
Example 1 so as to have a thickness of 0.4 mm on a copper stranded wire of mm ²
By extruding and coating the inner-coated fluorine-containing elastomers of Comparative Examples 1 to 5 and Comparative Examples 1 to 7, the inner-coated electric wires of Examples 1 to 5 and Comparative Examples 1 to 7 were obtained.

Next, the outer coated fluoroelastomer of Examples 1 to 5 and Comparative Examples 1 to 7 was placed on the inner coated electric wires of Examples 1 to 5 and Comparative Examples 1 to 7 obtained above by a sub-extruder. Was extruded and coated to a thickness of 0.04 to 0.05 mm to obtain an uncrosslinked fluorine-containing elastomer-coated electric wire.

Next, the non-crosslinked fluorine-containing elastomer-coated electric wire obtained here was passed through an electron beam cross-linking device, and was subjected to 10 Mr
The crosslinked fluorine-containing elastomer-coated electric wires of Examples 1 to 5 and Comparative Examples 1 to 7 were obtained by irradiating an electron beam of ad.

FIG. 1 is a cross-sectional view of the crosslinked fluorine-containing elastomer-coated electric wire of Example 1 thus obtained.

In FIG. 1, reference numeral 1 denotes a stranded conductor, reference numeral 21 denotes an insulated cross-linked fluorine-containing elastomer insulating layer, reference numeral 22 denotes an outer-coated cross-linked fluorine-containing elastomer insulating layer, and reference numeral 3 denotes a cross-linked fluorine-containing elastomer-coated electric wire.

Next, two of the crosslinked fluorine-containing elastomer-coated electric wires shown in FIG. 1 and the inclusion were twisted by a twisting machine to obtain a stranded product.

Next, a cable was manufactured by arranging two extruders, a main extruder and a sub-extruder, in tandem in the same manner as in the extrusion coating operation of the cable core.

Here, the main extruder is a 40 mm main extruder in which the temperature of the cylinder 1 is 100 ° C., the temperature of the cylinder 2 (head) is 200 ° C., and L / D = 22.

The temperature of the cylinder 1 is 100 ° C., the temperature of the cylinder 2 (head) is 270 ° C.
A 40 mm sub-extruder with L / D = 22.

First, the inner extruded fluorine-containing elastomer sheath layer of each of Examples 1 to 5 and Comparative Examples 1 to 7 was extruded and coated to a thickness of 0.7 mm on the outer periphery of the twisted product by the main extruder. An uncrosslinked crosslinked fluorine-containing elastomer-coated cable was obtained by extruding and coating the outer-coated fluorine-containing elastomer sheath layers of Examples 1 to 5 and Comparative Examples 1 to 7 by a sub-extruder to a thickness of 0.1 mm. .

Next, these uncrosslinked fluoroelastomer-coated cables were passed through an electron beam crosslinking device, and then 10 Mrad
By irradiating the electron beams of Examples 1 to 5, and the cross-linked fluorine-containing elastomer coated cables of Examples 1 to 5 and Comparative Examples 1 to 7, respectively.

FIG. 2 shows a cross-sectional view of the crosslinked fluorine-containing elastomer-coated cable of Example 1 thus obtained.

In FIG. 2, 1 is a stranded conductor, 21 is an inner-coated crosslinked fluorine-containing elastomer insulating layer, 22 is an outer-coated crosslinked fluorine-containing elastomer insulating layer, 3 is a cross-linked fluorine-containing elastomer-coated electric wire of a core strand, and 4 is an interposed wire. An object, 51 is an inner covering fluorine-containing elastomer sheath layer, 52 is an outer covering fluorine-containing elastomer sheath layer, and 6 is a cable.

[Method for Testing Characteristics of Fluorine-Containing Elastomer-Coated Wires and Cables] Next, characteristics tests were performed on the obtained fluorine-containing elastomer-coated wires and cables of Examples 1 to 5 and Comparative Examples 1 to 7.

A. Presence / absence of die squeezing during extrusion coating The presence / absence of die squass was observed silently.

B. Tensile strength test First, a copper-containing wire was extracted from each of the obtained fluorine-containing elastomer-coated wires and cables of Examples 1 to 5 and Comparative Examples 1 to 7 to take out a fluorine-containing elastomer coating layer.

Next, the collected Examples 1 to 5 and Comparative Example 1
Each of the fluorine-containing elastomer coating layers Nos.
A tensile test was performed according to IS-K-6301.

C. Heat aging resistance test Each of the fluoroelastomer coating layers of Examples 1 to 5 and Comparative Examples 1 to 7 collected in the above a was placed in a gear oven aging tester and aged at 232 ° C for 7 days.

Next, aged Examples 1 to 5 and Comparative Example 1
Each of the fluorine-containing elastomer coating layers Nos.
A tensile test was performed according to IS-K-6301.

D. Cut-through resistance The fluorinated elastomer-coated electric wires / cables of Examples 1 to 5 and Comparative Examples 1 to 7 obtained above were subjected to UL su.
A cut-through resistance test was performed at 200 ° C. in accordance with Bject 758.

E. Wire Bundle Adhesion 300 m of the fluoroelastomer-coated wires and cables obtained in Examples 1 to 5 and Comparative Examples 1 to 7 obtained above were sampled and wound into a bundle having a diameter of 200 mm. Next, a weight of 5 kg was placed on the bundle and left for 24 hours. After standing for 24 hours, the electric wires were pulled out of the bundle, and those having no adhesion were evaluated as ○, and those having adhesion were evaluated as ×.

[Characteristic Test Results of Fluorine-Containing Elastomer-Coated Wires / Cables] Table 1 shows the special test results of the fluorine-containing elastomer-coated wires / cables of Examples 1 to 5 and Comparative Examples 1 to 7.

As can be seen from Table 1, the fluorine-containing elastomer coating of the wires and cables of Comparative Example 1 has the drawback that the tensile strength is small and the cut-through is small.

The fluorine-containing elastomer-coated electric wire of Comparative Example 2
The fluorine-containing elastomer coating of the cable has the drawbacks of low elongation, poor heat aging resistance, and small cut-through.

The fluorine-containing elastomer-coated electric wire of Comparative Example 3
The fluoroelastomer coating of the cable has the disadvantage that the cut-through is as small as 50.

The fluorine-containing elastomer-coated electric wire of Comparative Example 4
Fluoro-elastomer coatings on cables suffer from low tensile strength and elongation and bundle stickiness.

The fluorine-containing elastomer-coated electric wire of Comparative Example 5
Fluoro-elastomer coatings on cables have the disadvantage of low tensile strength.

The fluorine-containing elastomer-coated electric wire of Comparative Example 6
Cables suffer from die squeezing during extrusion coating, and their fluoroelastomer coatings suffer from low tensile strength, low cut-through, and bundle stickiness.

The fluorine-containing elastomer-coated electric wire of Comparative Example 7
Fluoro-elastomer coatings on cables suffer from low tensile strength and elongation and low cut-through.

On the other hand, the fluorinated elastomer-coated electric wires and cables of Examples 1 to 5 did not generate die scabs at the time of extrusion coating, did not cause poor adhesion even when bundled, and performed a terminal processing work. It does not degrade the working environment, and its fluorine-containing elastomer coating has excellent tensile strength properties, elongation properties, heat aging resistance, cut-through resistance, etc. It is suitable.

Here, the formation of die scum during extrusion coating can be suppressed because the coating layer is compatible with the inner coating layer made of a poorly compatible tetrafluoroethylene-propylene copolymer / polyvinylidene fluoride blend. Is divided into two layers, an outer coating layer composed of a blend of a tetrafluoroethylene-propylene copolymer / ethylene-tetrafluoroethylene copolymer, which is excellent, and the outer coating layer is continuously formed immediately after the inner coating layer is extruded and coated. This is because they are extruded and covered.

[0066]

The fluorine-containing elastomer-coated electric wire of the present invention
According to the cable and the method for manufacturing the same, no die scabs are generated during extrusion coating, no adhesion failure occurs even when bundled, and the working environment does not deteriorate even when the terminal processing work is performed. The fluoroelastomer coating layer is excellent in tensile strength characteristics, elongation characteristics, heat aging resistance, cut-through resistance and the like, and is industrially useful.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a crosslinked fluorine-containing elastomer-coated electric wire according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the crosslinked fluorine-containing elastomer-coated cable according to the first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stranded conductor 21 Inner coating bridge | crosslinking fluorine-containing elastomer insulation layer 22 Outer coating bridge | crosslinking fluorine-containing elastomer insulation layer 3 Crosslinking bridge | crosslinking fluorine-containing elastomeric sheath wire 4 Inclusion 51 Inner coating bridge | crosslinking fluorine-containing elastomer sheath layer 52 Outside coating bridge | crosslinking fluorine-containing elastomer sheath layer 6 Cable

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 27/18 C08L 27/18 F-term (Reference) 4J002 BD142 BD151 BD152 DE236 FB076 FB106 FB146 FB236 FD016 GQ01 5G305 AA02 AB17 AB24 AB36 BA15 BA22 CA03 CA38 CA47 CA51 CA54 CC11 CD01 DA12 DA23 5G315 CA02 CA03 CB01 CC09 CD07 CD15

Claims (5)

[Claims] 1. A fluoroelastomer-coated cable having a fluoroelastomer coating layer provided on a conductor or on the outer periphery of a cable core, wherein the fluoroelastomer coating layer has a weight ratio of tetrafluoroethylene-propylene copolymer / polyvinylidene. Fluoride = 50 / 50-95 /
5 Calcium carbonate is added to 100 parts by weight of the blend.
To 200 parts by weight of an inner coating layer comprising a crosslinked product of a fluorine-containing elastomer blend, and a weight ratio of tetrafluoroethylene-propylene copolymer / ethylene-tetrafluoroethylene copolymer = 50 / 50- 95 /
5. A fluorine-containing elastomer-coated electric wire or cable, comprising: an outer coating layer comprising a crosslinked product of a 5-blend. 2. An outer coating layer comprising tetrafluoroethylene-
Propylene copolymer / ethylene-tetrafluoroethylene copolymer = 50 / 50-95 / 5 blend 10
5 to 150 parts by weight of surface-treated calcium carbonate per 0 parts by weight
The fluorine-containing elastomer-coated electric wire or cable according to claim 1, comprising a crosslinked product of a fluorine-containing elastomer blend to which parts by weight are added. 3. The fluoroelastomer-coated electric wire or cable according to claim 1, wherein the calcium carbonate has been surface-treated with any one of silica, vinyl silane, amino silane and fatty acid. 4. The calcium carbonate has an average particle diameter of φ2.0 μm.
The fluorine-containing elastomer-coated electric wire / cable according to claim 1, wherein the electric wire / cable is: 5. On a conductor or an outer periphery of a cable core,
In a method for manufacturing a fluorine-containing elastomer-coated electric wire or cable for extruding and coating an inner fluorine-containing elastomer coating layer and an outer fluorine-containing elastomer coating layer, the outer coating is formed on the inner coating layer immediately after the inner coating layer is extruded and coated. A method for producing a fluoroelastomer-coated electric wire or cable, comprising extruding and coating a layer.