JP7019623B2 - Cabtyre cables, insulated wires for cabtire cables and their manufacturing methods - Google Patents

Description

The present invention relates to a cabtire cable, an insulated wire for a cabtire cable used for the cabtire cable, and a method for manufacturing the same.

The cabtire cable has a rubber-based insulating layer and a sheath on the outer periphery of the conductor, and is coated with a natural rubber or polychloroprene rubber composition having high mechanical strength as a sheath. The cabtire cable is widely used mainly as a power supply electric wire at a construction site.
When connecting a cabtire cable, the insulating layer (including the inner insulating layer) and the sheath at the end of the cable are usually partially removed and electrically connected to a power source or another cable. However, when the insulating layer is removed from the insulated wire in the cabtire cable, a part of the insulating layer of the part to be removed remains on the conductor without being peeled off, or the cut end face of the insulating layer of the part not targeted for removal is cut. A whiskers (a linear body (hair-like body) derived from the insulating layer, which cannot cut the insulating layer in the thickness direction and remains on the cut end face of the insulating layer (extending from the cut end face)) are generated and are insulated. In some cases, the peelability of the layer was inferior, and in some cases, the conductor itself was stretched because the insulating layer and the conductor were adhered to each other. Therefore, by providing an inner insulating layer (so-called separator layer) inside the insulating layer, a method is adopted to reduce the degree of adhesion between the insulating layer and the conductor, improve the peelability of the insulating layer, and prevent the conductor from stretching. Has been done. For example, Patent Document 1 and Patent Document 2 describe a cabtire cable having a separator layer on a conductor and the outer periphery thereof being covered with an insulating layer.
As the separator layer, for example, a layer using a resin such as paper and polyethylene terephthalate has been used. For example, Patent Document 3 proposes a technique of using a composite tape having a rubber coating on at least one surface of a cloth or a film as a separator layer. Further, Patent Document 4 describes that a polyester tape or a nylon tape may be used as the separator layer.

Jikkensho 58-38931 Gazette Jitsukaihei 7-16325 Japanese Unexamined Patent Publication No. 61-2708 Japanese Unexamined Patent Publication No. 2016-95994

The cabtire cable is used for wiring, in particular, for electrical connection of a moving part of a machine tool, and is moved while being energized at a work site or the like. At that time, since bending and stretching are repeated many times and mechanically, the cabtire cable is required to have excellent bending durability (property that it is difficult to break even after many bendings).
Further, for a cabtire cable having a separator layer as described above, the inner insulating layer (separator layer) is not peeled off and remains on the conductor when peeled, and the insulating layer (inner insulating layer and outer insulating layer) is left. There was still room for improvement in the peelability of the layer).
Further, regarding the sheath, there is still room for improvement in the peelability of the sheath, such as the sheath portion cannot be peeled off at the time of peeling.

The present invention relates to a cabtire cable having excellent bending durability and excellent peeling property of an insulating layer and a sheath, and an insulated wire for a cabtire cable having an insulating layer having excellent peeling property used for the cabtire cable. The issue is to provide. Another object of the present invention is to provide a method for manufacturing the above-mentioned cabtire cable and an insulated wire for a cabtire cable.

The present inventors have an insulating layer containing a polyolefin resin as an insulating layer covering the outer periphery of a conductor, and an insulating layer containing at least one cured product of ethylene rubber and a styrene-based elastomer as an insulating layer covering the outer periphery thereof. A cabtire cable having a sheath of a silanol condensed cured product of a specific silane crosslinkable composition on the outer periphery of an insulated wire for a cabtire cable having a layer has excellent bending durability and excellent peeling of an insulating layer and a sheath. I found that it has both sex and sex. Based on this finding, the present inventors have further studied and came to the present invention.

That is, the subject of the present invention has been achieved by the following means.
[1]
A cabtire cable in which the outer circumference of an insulated wire is covered with a sheath.
The insulated wire has a conductor, an inner insulating layer that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer.
The inner insulating layer contains a polyolefin resin, and the inner insulating layer contains a polyolefin resin.
The outer insulating layer comprises at least one cured product of ethylene rubber and a styrene-based elastomer.
A cabtire cable in which the sheath is made of a silanol condensed cured product of the following silane crosslinkable composition J.
[Silane Crosslinkable Composition J]
1 to 200 parts by mass of the inorganic filler (Q) and 2 parts by mass of the silane coupling agent (F) grafted with the base resin (B) with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. Silane crosslinkable composition J containing 15.0 parts by mass or less and a silanol condensation catalyst (Y).
[2]
The polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof [1]. The cab tire cable described in.
[3]
The cabtire cable according to [1] or [2], wherein the outer insulating layer is made of a silanol condensed cured product of the following silane crosslinkable composition I.
[Silane Crosslinkable Composition I]
Silane coupling in which 1 to 400 parts by mass of the inorganic filler (P) and the base resin (A) are crosslinked with 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer. Silane crosslinkable composition I containing 1 to 15.0 parts by mass of the agent (E) and a silanol condensation catalyst (X).
[4]
The cabtire cable according to any one of [1] to [3], wherein the base resin (B) contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer.
[5]
An insulated wire for a cabtire cable having a conductor, an inner insulating layer covering the outer periphery of the conductor, and an outer insulating layer covering the outer periphery of the inner insulating layer.
An insulated wire for a cabtire cable, wherein the inner insulating layer contains a polyolefin resin, and the outer insulating layer contains a cured product of at least one of ethylene rubber and a styrene-based elastomer.
[6]
The polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof [5]. Insulated wire for cab tire cables as described in.
[7]
The insulated wire for a cabtire cable according to [5] or [6], wherein the outer insulating layer is made of a silanol condensed cured product of the following silane crosslinkable composition I.
[Silane Crosslinkable Composition I]
Silane coupling in which 1 to 400 parts by mass of the inorganic filler (P) and the base resin (A) are crosslinked with 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer. Silane crosslinkable composition I containing 1 to 15.0 parts by mass of the agent (E) and a silanol condensation catalyst (X).
[8]
It has a conductor, an inner insulating layer containing a polyolefin resin that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer and contains a cured product of at least one of ethylene rubber and a styrene-based elastomer. It is a method of manufacturing a cabtire cable in which the outer circumference of an insulated wire is covered with a sheath.
A method for manufacturing a cabtire cable, wherein the inner insulating layer, the outer insulating layer, and the sheath are formed by the following steps (1), (2), and steps (k) to (n), respectively.
Step (1): The outer periphery of the conductor is coated with a polyolefin resin to form the inner insulating layer. Step (2): The outer periphery of the inner insulating layer is coated with at least one of ethylene rubber and a styrene-based elastomer. Step of curing at least one of the ethylene rubber and the styrene-based elastomer to form the outer insulating layer Step (k): Organic peroxide with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. (D) A silane coupling agent (F) having 0.003 to 0.3 parts by mass of an inorganic filler (Q), 1 to 200 parts by mass of an inorganic filler (Q), and a grafting reaction site capable of crosslinking with the base resin (B). ) A silane master batch containing a silane crosslinkable resin H by melt-mixing more than 2 parts by mass and 15.0 parts by mass or less to carry out a grafting reaction between the grafting reaction site and the base resin (B). Step of preparing L Step (l): A step of melt-mixing the silane master batch L and the silanol condensation catalyst (Y) to obtain a silane crosslinkable composition J Step (m): In the silane crosslinkable composition J Step (n): Step of contacting the sheath precursor with water to form the sheath [9].
The polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof [8]. The method for manufacturing a cab tire cable described in.
[10]
The method for manufacturing a cabtire cable according to [8] or [9], wherein the inner insulating layer is not heated to a temperature equal to or higher than the melting point of the polyolefin resin after the coating in the step (2).
[11]
The method for manufacturing a cabtire cable according to any one of [8] to [10], wherein the step (2) is performed by the following steps (a) to (d).
Step (a): With respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer, 0.01 to 0.6 parts by mass of the organic peroxide (C) and an inorganic filler ( P) 1 to 400 parts by mass and 1 to 15.0 parts by mass of a silane coupling agent (E) having a grafting reaction site capable of crosslinking with the base resin (A) are melt-mixed and the graft is formed. Step of preparing a silane master batch K containing a silane crosslinkable resin G by grafting a chemical reaction site with the base resin (A) Step (b): The silane master batch K and a silanol condensation catalyst (X). ) Is melt-mixed to obtain a silane crosslinkable composition I. Step (c): A step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition I to form an outer insulating layer precursor (d). ): A step of contacting the outer insulating layer precursor with water to form the outer insulating layer [12].
The production of the cabtire cable according to [11], wherein a part of the base resin (A) is melt-mixed in the step (a) and the rest of the base resin (A) is melt-mixed in the step (b). Method.
[13]
The method for manufacturing a cabtire cable according to any one of [8] to [12], wherein the base resin (B) contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer.
[14]
Any one of [8] to [13], wherein a part of the base resin (B) is melt-mixed in the step (k), and the rest of the base resin (B) is melt-mixed in the step (l). The method of manufacturing the cabtire cable described in the section.
[15]
The method for manufacturing a cabtire cable according to any one of [8] to [14], wherein the balance of the base resin (B) contains chloroprene rubber.
[16]
The method for manufacturing a cabtire cable according to any one of [8] to [15], wherein the inorganic filler (Q) contains 2 parts by mass or more of silica.
[17]
The method for manufacturing a cabtire cable according to any one of [8] to [16], wherein the mixing amount of the inorganic filler (Q) in the step (k) is 3 to 60 parts by mass.
[18]
The method for manufacturing a cabtire cable according to any one of [8] to [17], wherein the melt mixing in the step (k) is performed with a closed mixer.
[19]
It has a conductor, an inner insulating layer containing a polyolefin resin that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer and contains a cured product of at least one of ethylene rubber and a styrene-based elastomer. It is a method of manufacturing insulated wires for cabtire cables.
A method for manufacturing an insulated wire for a cabtire cable, wherein the inner insulating layer and the outer insulating layer are formed by the following steps (1) and (2), respectively.
Step (1): The outer periphery of the conductor is coated with a polyolefin resin to form the inner insulating layer. Step (2): The outer periphery of the inner insulating layer is coated with at least one of ethylene rubber and a styrene-based elastomer. Step of curing at least one of the ethylene rubber and the styrene-based elastomer to form the outer insulating layer [20]
The polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof [19]. A method for manufacturing an insulated wire for a cab tire cable described in 1.
[21]
The method for manufacturing an insulated wire for a cabtire cable according to [19] or [20], wherein the inner insulating layer is not heated to a temperature exceeding the melting point + 60 ° C. of the polyolefin resin after the coating in the step (2).
[22]
The method for manufacturing an insulated wire for a cabtire cable according to any one of [19] to [21], wherein the step (2) is performed by the following steps (a) to (d).
Step (a): With respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer, 0.01 to 0.6 parts by mass of the organic peroxide (C) and an inorganic filler ( P) 1 to 400 parts by mass and 1 to 15.0 parts by mass of a silane coupling agent (E) having a grafting reaction site capable of crosslinking with the base resin (A) are melt-mixed and the graft is formed. Step of preparing a silane master batch K containing a silane crosslinkable resin G by grafting a chemical reaction site with the base resin (A) Step (b): The silane master batch K and a silanol condensation catalyst (X). ) Is melt-mixed to obtain a silane crosslinkable composition I. Step (c): A step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition I to form an outer insulating layer precursor (d). ): A step of contacting the outer insulating layer precursor with water to form the outer insulating layer [23].
The insulation for a cabtire cable according to [22], wherein a part of the base resin (A) is melt-mixed in the step (a) and the rest of the base resin (A) is melt-mixed in the step (b). How to make electric wires.

The numerical range represented by using "-" in the present specification means a range including the numerical values before and after "-" as the lower limit value and the upper limit value.

The cabtire cable of the present invention has excellent bending durability and excellent peeling property of an insulating layer and a sheath. The insulated wire for a cabtire cable of the present invention is excellent in peeling property of the insulating layer, and can be suitably used for the above-mentioned cabtire cable. Further, according to the method for manufacturing a cabtire cable and the method for manufacturing an insulated wire for a cabtire cable of the present invention, it is possible to manufacture a cabtire cable and an insulated wire for a cabtire cable having the above-mentioned excellent characteristics.

It is an end view which shows the structure of one aspect of the cabtire cable of this invention. It is an end view which shows the structure of another aspect of the cabtire cable of this invention. It is an end view which shows the structure of one aspect of the insulation electric wire for a cabtire cable of this invention. It is a schematic diagram which shows the outline of the apparatus used for a bending durability test.

[[Insulated wires for cabtire cables and cabtire cables]]
The cabtire cable of the present invention is a cable formed by covering the outer periphery of an insulated wire for a cabtire cable with a sheath. The insulated wire for a cabtire cable (hereinafter, simply referred to as an insulated wire) contained in this cabtire cable has a conductor, an inner insulating layer covering the outer periphery of the conductor, and an outer insulating layer covering the outer periphery of the inner insulating layer. The inner insulating layer contains a polyolefin resin, and the outer insulating layer contains a cured product of at least one of an ethylene rubber and a styrene-based elastomer. Further, the sheath of this cabtire cable is made of a silanol condensed cured product of a specific silane crosslinkable composition J described later.
The configuration of the cabtire cable and the insulated wire is not particularly limited except for the above, and the configuration of the normal cabtire cable and the insulated wire can be used.
In the present invention, covering the outer circumference includes both a mode of directly covering the outer circumference and a mode of indirectly covering the outer circumference via another layer or member. Directly covering the outer circumference means that a predetermined layer is provided in contact with the outer peripheral surface of the conductor, in other words, no other layer or structure is interposed between the outer peripheral surface and the predetermined layer. Means that.

The number of conductors in the insulated wire may be one or a plurality. In the case of a plurality of pieces, it is preferable that they are twisted or arranged to form an aggregate. As the conductor, those usually used for insulated electric wires can be used without particular limitation, and single wire or stranded wire of annealed copper can be used. Further, as the conductor, in addition to bare wires such as copper, copper alloy, aluminum, and aluminum alloy, tin-plated conductors and conductors having an enamel coating can also be used. The outer diameter of the conductor can be appropriately set according to the application and the like.

The inner insulating layer covers the outer circumference of the conductor. The inner insulating layer preferably directly covers the outer periphery of the conductor, but may have inclusions as long as the effect of the present invention is not impaired. In the embodiment in which the inner insulating layer covers the outer periphery of the conductor, when an aggregate of a plurality of conductors is used, it suffices to cover the outer periphery of the integrated aggregate, and each conductor forming the aggregate may be covered. It does not have to cover the outer circumference. Further, the inner insulating layer may be arranged so as to have a partial space between the inner insulating layer and the conductor. That is, when the outer peripheral surface of the conductor or the aggregate has unevenness, the inner insulating layer does not have to follow the uneven shape (in contact with the uneven surface).
The thickness of the inner insulating layer can be appropriately determined according to the application and the like. For example, the average thickness of the inner insulating layer is preferably 0.1 to 0.5 mm, more preferably 0.4 to 0.5 mm. Here, the average thickness of the inner insulating layer is an arbitrary point when observing an arbitrary cross section of the tubular piece obtained by pulling out a conductor from the insulated wire and perpendicular to the axis of the tubular piece with a microscope. It is the average value of the thickness measured at four points of the central angle of 0 degree, 90 degree, 180 degree, and 270 degree in the circumferential direction as the starting point (0 degree). Further, when an aggregate of a plurality of conductors is used, the central angles are 0 degrees and 90 degrees in the circumferential direction, starting from the portion where the thickness of the inner insulating layer (X) is the thinnest in the above arbitrary cross section. It is an average value of the thickness measured at four points of 180 degrees and 270 degrees.
The inner insulating layer may function as a normal insulating layer, and may further function as a so-called separator as a layer having a function of controlling the adhesion between the conductor and the outer insulating layer.

The outer insulating layer covers the outer periphery of the inner insulating layer. The outer insulating layer may be one layer or a plurality of layers, and in the case of a plurality of layers, at least one layer of the outer insulating layer is a layer containing at least one cured product of ethylene rubber and a styrene-based elastomer. It is preferable that the outer insulating layer that directly covers the outer periphery of the inner insulating layer is a layer containing at least one cured product of ethylene rubber and a styrene-based elastomer. As the remaining outer insulating layer, the insulating layer usually used for a cabtire cable or an insulated wire can be used without particular limitation.
The thickness of the outer insulating layer (layer containing at least one cured product of ethylene rubber and styrene-based elastomer) can be appropriately determined according to the intended use and the like. The average thickness of the outer insulating layer is preferably 0.2 to 1.8 mm, more preferably 0.4 to 1.4 mm. The total thickness in the case of a plurality of layers is not particularly limited and is appropriately determined. The average thickness of the outer insulating layer can be measured by the same method as the average thickness of the inner insulating layer (X), and is an average value of the thicknesses measured at four points specified by the same method as described above.

In the following description, the inner insulating layer and the outer insulating layer may be collectively referred to as an insulating layer.

In the cabtire cable, the number of insulated wires arranged in the sheath may be one or a plurality. When a plurality of insulated wires are arranged, the plurality of insulated wires may be twisted or arranged side by side (a single insulated wire or an aggregate of a plurality of insulated wires is referred to as a cable core. Sometimes.).

The sheath covers the outer circumference of the insulated wire (cable core). In the mode in which the sheath covers the outer periphery of the insulated wire, when an aggregate of a plurality of insulated wires is used, it is sufficient to cover the outer periphery of the integrated aggregate, and each insulated wire forming the aggregate is formed. It is not necessary to cover individual insulated wires. Further, the sheath may be arranged so as to have a partial space between the sheath and the insulated electric wire.
The thickness of the sheath can be appropriately determined according to the intended use and the like. The average thickness of the sheath is preferably 0.3 to 6.0 mm, more preferably 0.5 to 3.0 mm. Here, the average thickness of the sheath is an arbitrary point when observing an arbitrary cross section of the tubular piece obtained by pulling out an insulated wire from the cabtire cable and perpendicular to the axis of the tubular piece with a microscope. It is the average value of the thickness measured at four points of the central angle of 0 degree, 90 degree, 180 degree, and 270 degree in the circumferential direction as the starting point (0 degree). When a cable core is used, measurements are taken at four points in the circumferential direction at central angles of 0 degrees, 90 degrees, 180 degrees, and 270 degrees, starting from the portion where the thickness of the sheath is the thinnest in the above arbitrary cross section. It is the average value of the thickness.
A mold release agent layer containing talc or the like may be provided between the outer insulating layer and the sheath.

Depending on the classification, the cabtire cable may be classified into a cabtire cable and a cabtire cord based on the rated voltage, and the cabtire cable of the present invention includes any of these. The cabtire cable of the present invention is preferably a cabtire cable in the above category.

Preferred embodiments of the cabtire cable and the insulated wire of the present invention will be described with reference to the drawings.
One embodiment of the cabtire cable of the present invention whose end view is shown in FIG. 1 is an embodiment of one conductor 11, an inner insulating layer 21 that covers the outer periphery of the conductor 11, and an outer side that covers the outer periphery of the inner insulating layer 21. A cabtire cable 101 having a single insulated wire made of an insulating layer 31 and a sheath 41 covering the outer periphery of the outer insulating layer 31.
Another embodiment of the cabtire cable of the present invention whose end view is shown in FIG. 2 covers one conductor 12, an inner insulating layer 22 that covers the outer periphery of the conductor 12, and the outer periphery of the inner insulating layer 22. It is a cabtire cable 102 having three insulated wires made of an outer insulating layer 32 and a sheath 42 covering the outer periphery of the insulated wires. The cabtire cable shown in FIG. 2 is the same as the cabtire cable shown in FIG. 1 except that three insulated wires are used.
The preferred form of the cabtire cable is not limited to that shown in FIGS. 1 and 2, and as described above, the cable core may have two insulated wires or four or more insulated wires. You may have.
One embodiment of the insulated wire of the present invention whose end view is shown in FIG. 3 is an embodiment of one conductor 1, an inner insulating layer 2 covering the outer periphery of the conductor 1, and an outer insulating layer 3 covering the inner insulating layer 2. It is an insulated wire 10 made of. The insulated wire 10 is the same as the insulated wire of the cabtire cable shown in FIGS. 1 and 2, respectively.
The preferred form of the insulated wire is not limited to that shown in FIG. 3, and may have a plurality of conductors as described above.

It is preferable that the inner insulating layer and the outer insulating layer are in contact with each other with an adhesive force that does not easily separate (peeling) in the peeling test of the insulating layer described later.

Each layer of the cabtire cable and the insulated wire of the present invention will be described in more detail including its components.

[Inner insulation layer]
The inner insulating layer contains a polyolefin resin. The inner insulating layer may contain a silanol condensed cured product of a polyolefin resin by a silane cross-linking method described later. As the cured product by the silane cross-linking method, among the polyolefin resins described later, a polyethylene resin or an ethylene-α-olefin copolymer cured by the silane cross-linking method is preferable.
The inner insulating layer may contain various additives generally used in electric wires, electric cables, electric cords and the like as long as the effects of the present invention are not impaired.

-Polyolefin resin-

The polyolefin resin is not particularly limited as long as it is a resin made of a polymer obtained by polymerizing or copolymerizing a compound having an ethylenically unsaturated bond (usually an alkene). Known polyolefin resins conventionally used for electric wires and cables can be used.
Examples of the polyolefin resin include resins made of polymers such as polyethylene, polypropylene, ethylene-α-olefin copolymers, and polyolefin copolymers having an acid copolymer component or an acid ester copolymer component, rubber of these polymers, or Examples thereof include elastomers (excluding ethylene rubber and styrene-based polymers).
The inner insulating layer may contain one type of polyolefin resin alone or two or more types.
The resin component forming the inner insulating layer is preferably 25 to 100% by mass, more preferably 50 to 100% by mass of the polyolefin resin.

Examples of the polyethylene resin include high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), ultra-high molecular weight polyethylene (UHMW-PE), linear low-density polyethylene (LLDPE), and ultra-low-density polyethylene. (VLDPE) can be mentioned. Of these, linear low-density polyethylene, low-density polyethylene, medium-density polyethylene, and high-density polyethylene are preferable.

The polypropylene resin includes a homopolymer of propylene, an ethylene-propylene copolymer such as random polypropylene as a copolymer, and a resin of block polypropylene. Of these, random polypropylene is preferable.

Examples of the resin made of an ethylene-α-olefin copolymer include a resin made of an ethylene-butylene copolymer and an ethylene-α-olefin copolymer synthesized in the presence of a single site catalyst.

Examples of the resin composed of a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component include an ethylene-vinyl acetate copolymer, an ethylene- (meth) acrylic acid copolymer, and an ethylene- (meth) acrylic acid. Examples thereof include resins made of an alkyl copolymer (preferably 1 to 12 carbon atoms) copolymer and the like. Of these, an ethylene-alkyl acrylate copolymer is preferable.

The polyolefin resin may be acid-modified with an unsaturated carboxylic acid or a derivative thereof, which is usually used.

The polyolefin resin preferably contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof.

Further, the polyolefin resin may be a crosslinkable resin, and may be, for example, a silane grafted polyolefin resin (silane crosslinkable polyolefin resin) in which a silane coupling agent is graft-reacted with the polyolefin resin. As the polyolefin resin used for the silane graft polyolefin resin, the above-mentioned polyolefin resin, for example, a resin such as polyethylene or an ethylene-α-olefin copolymer can be used.
When the inner insulating layer is a silanol condensed product layer of a polyolefin resin, the inner insulating layer may be formed by further curing a commercially available silane graft resin, and in addition to the polyolefin resin, a silane coupling agent. , Organic peroxides, and silanol condensation catalysts may be used. Examples of the silane coupling agent, the organic peroxide, and the silanol condensing agent include the silane coupling agent (E), the organic peroxide (C), and the silanol condensing agent described as components of the silane crosslinkable composition I described later. X) can be used. Further, the polyolefin resin may be used as a mixture containing other resin components in addition to these, and the inner insulating layer may be formed by using this mixture.

[Outer insulation layer]
The outer insulating layer contains a cured product of at least one of ethylene rubber and a styrene-based elastomer.
Further, from the viewpoint of further improving bending durability and further imparting flexibility and heat resistance, the outer insulating layer preferably contains a cured product of ethylene rubber.

The outer insulating layer may contain a cured product of at least one of ethylene rubber and a styrene-based elastomer by a chemical cross-linking method, or may contain a cured product of at least one of ethylene rubber and a styrene-based elastomer by a silane cross-linking method. .. Further, at least one of ethylene rubber and styrene-based elastomer may contain a cured product obtained by an electron beam cross-linking method. From the viewpoint of bending durability, it is preferable to contain a cured product obtained by the silane cross-linking method. Here, the chemical cross-linking method refers to a method (organic peroxide cross-linking method) in which polymers are directly cross-linked with radicals generated by decomposing organic peroxide or the like by applying heat. Further, in the silane cross-linking method, a silane coupling agent having an unsaturated group is subjected to a silane grafting reaction (simply also referred to as a grafting reaction) in a polymer in the presence of an organic peroxide to obtain a silane grafted polymer. A method of obtaining a polymer crosslinked via a silane coupling agent by contacting the silane graft polymer with water, preferably after obtaining the polymer, if desired, and then preferably in the presence of a silanol condensation catalyst. The silane cross-linking method using a silane coupling agent as a cross-linking agent is a kind of chemical cross-linking method, but in the present invention, the term "chemical cross-linking" refers to the above-mentioned organic peroxide cross-linking method in which polymers are directly cross-linked.

The ethylene rubber and the styrene-based elastomer are particularly limited as long as they have a site capable of a cross-linking reaction (for example, an unsaturated bond site of a carbon chain, a carbon atom having a hydrogen atom) in the main chain or at the end thereof. Not done. A site capable of silane cross-linking, that is, a site capable of grafting reaction with a grafting reaction site of a silane coupling agent (for example, an unsaturated bond site of a carbon chain) in the presence of radicals generated from an organic peroxide described later. , A carbon atom having a hydrogen atom) in the main chain or at the end thereof is preferable. As the ethylene rubber and the styrene-based elastomer, those described as components of the silane crosslinkable composition I described later can be used.

The total content of ethylene rubber and the styrene-based elastomer in 100% by mass of the resin component constituting the outer insulating layer and the preferable content of each are the same as those described later as the description of the base resin (A). .. The resin component constituting the outer insulating layer may contain a non-aromatic organic oil and other resin components, and the types and contents thereof are the same as those described as the description for the base resin (A). be.

When the cured product is formed by a chemical cross-linking method, an organic peroxide is used in addition to at least one of ethylene rubber and a styrene-based elastomer. Crosslinking agents (eg, silane coupling agents, but not in combination with silanol condensation catalysts) may also be used. As the organic peroxide and the silane coupling agent, the organic peroxide (C) and the silane coupling agent (E) described as components of the silane crosslinkable composition I described later can be used.
When the cured product is formed by a chemical cross-linking method, the outer insulating layer is preferably a cured product of a composition containing the above components. In this composition, the content of the organic peroxide is preferably 1.5 to 4 parts by mass with respect to 100 parts by mass of the resin component. When a silane coupling agent is used, the content of the silane coupling agent is preferably 0.5 to 2 parts by mass with respect to 100 parts by mass of the resin component.

When the cured product is formed by the silane cross-linking method, a silane coupling agent, an organic peroxide, and a silanol condensing agent are used in addition to at least one of ethylene rubber and a styrene-based elastomer. Examples of the silane coupling agent, the organic peroxide, and the silanol condensing agent include the silane coupling agent (E), the organic peroxide (C), and the silanol condensing agent described as components of the silane crosslinkable composition I described later. X) can be used. Further, ethylene rubber and a styrene-based elastomer may be used as a mixture containing other resin components in addition to these (preferably the base resin (A) described later), and the outer insulating layer may be formed by using this mixture.

The outer insulating layer is preferably made of the silanol condensed cured product of the following [silane crosslinkable composition i] among the cured products obtained by the silane cross-linking method.

[Silane crosslinkable composition i]
A silane crosslinkable composition for an outer insulating layer containing at least one of an ethylene rubber and a styrene-based elastomer and a silane coupling agent grafted with at least one of the ethylene rubber and a styrene-based elastomer, and further containing a silanol condensation catalyst. i

Examples of the silane coupling agent, the organic peroxide, and the silanol condensing agent include the silane coupling agent (E), the organic peroxide (C), and the silanol condensing agent described as components of the silane crosslinkable composition I described later. X) can be used.
The silane crosslinkable composition i for the outer insulating layer can be prepared by the steps (2a) and (2b) described later.
The preferable content of each component in the silane crosslinkable composition i is the same as the blending amount of each component in the method for producing an insulated wire having steps (2a) to (2d) described later, and the preferred range is also the same. ..

The outer insulating layer is more preferably made of the silanol condensed cured product of the following [silane crosslinkable composition I], which contains a specific amount of an inorganic filler among the cured products obtained by the silane cross-linking method.

[Silane Crosslinkable Composition I]
A silane coupling agent grafted with 1 to 400 parts by mass of an inorganic filler (P) and a base resin (A) with respect to 100 parts by mass of a base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer. (E) A silane crosslinkable composition I containing 1 to 15.0 parts by mass and further containing a silanol condensation catalyst (X).

The silane crosslinkable composition I can be prepared by the steps (a) and (b) described later.
The preferable content of each component in the silane crosslinkable composition I is the same as the blending amount of each component in the method for producing an insulated wire having steps (a) to (d) described later, and the preferred range is also the same. ..

The outer insulating layer has a processing temperature close to the melting point of the polyolefin resin used for the inner insulating layer (preferably a melting point of the polyolefin resin used for the inner insulating layer + 20 ° C. or higher and a melting point of the polyolefin resin used for the inner insulating layer + 100 ° C. or lower). More preferably, at the melting point of the polyolefin resin used for the inner insulating layer + 60 ° C. or higher and the melting point of the polyolefin resin used for the inner insulating layer + 100 ° C. or lower), any of the above-mentioned compositions for forming the outer insulating layer is inner-insulated. It is preferably formed by covering the outer periphery of the layer. By coating the composition for forming the outer insulating layer at a processing temperature close to the melting point of the polyolefin resin used for the inner insulating layer, the inner insulating layer and the outer insulating layer can be adhered to each other, or these layers can be formed at the same time. It becomes possible to do.

Hereinafter, the components of the silane crosslinkable composition I and the materials used for the preparation thereof will be described.

<Base resin (A)>
The base resin (A) contains at least one of ethylene rubber and a styrene-based elastomer. In the presence of radicals generated from organic peroxides, which will be described later, ethylene rubber and styrene-based elastomers have a grafting reaction site of a silane coupling agent and a site capable of a grafting reaction (for example, an unsaturated bond site of a carbon chain, etc. A carbon atom having a hydrogen atom) is contained in or at the end of the main chain. When the base resin (A) contains at least one of ethylene rubber and a styrene-based elastomer, an outer insulating layer that contributes to bending durability can be formed.
The base resin (A) may contain a component other than the rubber or the elastomer, and examples of the component that may contain the base resin (A) include non-aromatic organic oils and other resins.
In this base resin (A), the content of each component is selected from the following range so that the total of each component is 100% by mass.

-Ethylene rubber-
The ethylene rubber is not particularly limited as long as it is a rubber (including an elastomer) made of a copolymer obtained by copolymerizing a compound having an ethylenically unsaturated bond, and known ones can be used. Preferred examples of the ethylene rubber include a rubber composed of a copolymer of ethylene and an α-olefin and a ternary copolymer of ethylene, an α-olefin and a diene. The diene component of the ternary copolymer may be a conjugated diene component or a non-conjugated diene component, and a non-conjugated diene component is preferable.

As the α-olefin component, each α-olefin component having 3 to 12 carbon atoms is preferable, and specific examples thereof include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. Each component such as 1-decene and 1-dodecene can be mentioned. Specific examples of the conjugated diene component include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like, and butadiene component and the like are preferable. Specific examples of the non-conjugated diene component include dicyclopentadiene (DCPD), ethylidene norbornene (ENB), 1,4-hexadiene and the like, and the ethylidene norbornene component is preferable.

Examples of the rubber made of a copolymer of ethylene and α-olefin include ethylene-propylene rubber, ethylene-butene rubber, ethylene-octene rubber and the like. Examples of the rubber made of a ternary copolymer of ethylene, α-olefin and diene include ethylene-propylene-diene rubber and ethylene-butene-diene rubber.
Among them, ethylene-propylene rubber, ethylene-butene rubber, ethylene-propylene-diene rubber, ethylene-butene-diene rubber are preferable, and ethylene-propylene rubber and ethylene-propylene-diene rubber are more preferable.

-Styrene-based elastomer-
The styrene-based elastomer refers to a polymer composed of an aromatic vinyl compound in the molecule.
The styrene-based elastomer is preferably a block copolymer and a random copolymer of a conjugated diene compound and an aromatic vinyl compound, or a hydrogenated product thereof.
Examples of the styrene-based elastomer include styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer (SIS), hydride SBS, and styrene-ethylene-ethylene-propylene-styrene block. Consists of copolymer (SEEPS), styrene-ethylene-propylene-styrene block copolymer (SEPS), hydride SIS, hydride styrene / butadiene rubber (HSBR), hydride acrylonitrile butadiene rubber (HNBR), etc. Can be mentioned.

-Non-aromatic organic oil-
The non-aromatic organic oil means that the number of carbon atoms constituting the aromatic ring is less than 30% with respect to the total number of carbon atoms, and those usually used for a resin composition can be used without particular limitation. .. As non-aromatic organic oils, paraffin-based oils in which the number of carbon atoms constituting the paraffin chain is 50% or more of the total number of carbon atoms, and paraffin-based oils in which the number of carbon atoms constituting the naphthen ring is 30 to 30% with respect to the total number of carbon atoms. Examples thereof include naphthenic oils having 40% and having less than 50% of the total number of carbon atoms constituting the paraffin chain, and paraffinic oils are preferable. One type of non-aromatic organic oil may be used alone, or two or more types may be used in combination.

-Other resin components-
The base resin (A) may contain a resin component (other resin component) other than the above. The other resin components are not particularly limited and may or may not have a site capable of a grafting reaction. As such a resin component, a polyolefin resin is preferable.
As the polyolefin resin, the polyolefin resin described in the above [Inner Insulating Layer] can be used.

The base resin (A) may contain an additive described later in addition to the above-mentioned components.

The total content of ethylene rubber and styrene-based elastomer in the base resin (A) is not particularly limited as long as it exceeds 0% by mass, preferably 5% by mass or more, more preferably 10% by mass or more, and 20% by mass or more. Is even more preferable. The upper limit is not particularly limited, but is preferably 85% by mass or less, more preferably 65% by mass or less, still more preferably 60% by mass or less.
The content of ethylene rubber in the base resin (A) is appropriately set within a range satisfying the above total content. The content of ethylene rubber in the base resin (A) is preferably 0 to 85% by mass, more preferably 5 to 50% by mass, and even more preferably 10 to 35% by mass.
The content of the styrene-based elastomer in the base resin (A) is appropriately set within a range satisfying the above total content. The content of the styrene-based elastomer in the base resin (A) is preferably 0 to 55% by mass, more preferably 0 to 40% by mass, still more preferably 0 to 35% by mass.
The content of the non-aromatic organic oil in the base resin (A) is not particularly limited, but is 0% by mass to equal to or less than the total amount of ethylene rubber and styrene-based elastomer, preferably 3% by mass to ethylene rubber and It is preferably 80% or less of the total amount of the styrene-based elastomer.
The content of the polyolefin resin in the base resin (A) is not particularly limited, but is preferably 10 to 95% by mass, more preferably 25 to 80% by mass, still more preferably 15 to 50% by mass.

<Organic peroxide (C)>
The organic peroxide (C) generates radicals by at least thermal decomposition, and as a catalyst, a graft reaction (silane coupling agent (E)) by a radical reaction of the silane coupling agent (E) with the base resin (A). ) And the site capable of the grafting reaction of the base resin (A), which is a covalent bond forming reaction, and also has a function of causing a (radical) addition reaction).
As the organic peroxide (C), those having the above-mentioned functions and used in radical polymerization or the conventional silane cross-linking method can be used without particular limitation. For example, benzoyl peroxide, dicumyl peroxide (DCP), 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane or 2,5-dimethyl-2,5-di- (tert-). Butylperoxy) hexin-3 is preferred.
The decomposition temperature of the organic peroxide (C) is preferably 80 to 195 ° C, particularly preferably 125 to 180 ° C. In the present invention, the decomposition temperature of the organic peroxide (C) means that when the organic peroxide (C) having a single composition is heated, the compound itself becomes two or more kinds of compounds at a certain temperature or temperature range. It means the temperature at which a decomposition reaction occurs. Specifically, it refers to the temperature at which heat absorption or heat generation starts when heated from room temperature at a temperature rise rate of 5 ° C./min in a nitrogen gas atmosphere by thermal analysis such as the DSC method.
As the organic peroxide (C), one type may be used, or two or more types may be used.

<Inorganic filler (P)>
In the present invention, the inorganic filler (P) has a site on the surface thereof where a reaction site such as a silanol group of the silane coupling agent (E) can form a hydrogen bond or a site where a covalent bond can be chemically bonded. If there is, it can be used without particular limitation. In this inorganic filler (P), OH groups (hydroxyl groups, water molecules of water-containing or crystalline water, OH groups such as carboxy groups) and amino groups can be chemically bonded to the reaction site of the silane coupling agent (E). , SH group and the like.
Examples of the inorganic filler (P) include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisk, and hydration. Metal hydrates such as aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite and other compounds having hydroxyl groups or crystalline water, boron nitride, silica (crystalline silica, amorphous silica). Etc.), carbon, clay, zinc oxide, tin oxide, titanium oxide, molybdenum oxide, antimony trioxide, silicone compound, quartz, talc, zinc borate, white carbon, zinc borate, zinc hydroxytinate, zinc tint be able to.
Among these, the inorganic filler (P) is preferably at least one of silica, aluminum hydroxide, and magnesium hydroxide.
As the inorganic filler (P), one type may be blended alone, or two or more types may be used in combination.

The average particle size of the inorganic filler (P) is preferably 0.2 to 10 μm, more preferably 0.3 to 8 μm, further preferably 0.4 to 5 μm, and particularly preferably 0.4 to 3 μm. The average particle size is determined by an optical particle size measuring device such as a laser diffraction / scattering type particle size distribution measuring device, which is dispersed with alcohol or water.

As the inorganic filler (P), an inorganic filler surface-treated with a silane coupling agent or the like can be used. For example, examples of the silane coupling agent surface-treated metal hydrate include Kisma 5L, Kisma 5P (trade names, magnesium hydroxide, manufactured by Kyowa Chemical Co., Ltd., etc.), aluminum hydroxide, and the like. The amount of the surface treatment of the inorganic filler with the silane coupling agent is not particularly limited, but is, for example, 2% by mass or less.

<Silane coupling agent (E)>
The silane coupling agent (E) has a grafting reaction with the base resin (A) in the silane crosslinkable composition I. As the silane coupling agent (E) (silane graft resin) grafted with the base resin (A), a commercially available product can be used, but the one prepared by the method described later has physical properties (both heat resistance and strength). Etc.), which is preferable.
The silane coupling agent (E) used in the preparation of the silane graft resin is a site capable of the grafting reaction of the base resin (A) in the presence of radicals generated by the decomposition of the organic peroxide (C). It is not particularly limited as long as it has a site (group or atom) capable of grafting reaction and a hydrolyzable silyl group capable of condensing silanol. Examples of such a silane coupling agent (E) include a silane coupling agent used in a conventional silane cross-linking method.
Examples of the silane coupling agent (E) include a silane coupling agent having an unsaturated group, and specific examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltributoxysilane, vinyldimethoxyethoxysilane, and vinyldimethoxy. Examples thereof include vinyl silanes such as butoxysilane, vinyldiethoxybutoxysilane, allyltrimethoxysilane, allyltriethoxysilane, vinyltriacetoxysilane, and (meth) acryloxysilane. Of these, vinyltrimethoxysilane or vinyltriethoxysilane is particularly preferable.
The silane coupling agent (E) may be used alone or in combination of two or more.
The silane coupling agent (E) may be used as it is or diluted with a solvent.

<Silanol condensation catalyst (X)>
The silanol condensation catalyst (X) has a function of causing a condensation reaction (promoting) of the hydrolyzable silyl group of the silane coupling agent (E) grafted on the base resin (A) in the presence of water. Based on the action of the silanol condensation catalyst (X), the base resins (A) are crosslinked with each other via the silane coupling agent (E).
The silanol condensation catalyst (X) is not particularly limited, and examples thereof include an organotin compound, a metallic soap, and a platinum compound. Examples of the organotin compound include organotin compounds such as dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctate, and dibutyltin diacetate.
The silanol condensation catalyst (X) may be used alone or in combination of two or more.

<Carrier resin (CA)>
The silanol condensation catalyst (X) used in the present invention is optionally mixed with the resin. The resin (also referred to as carrier resin (CA)) is not particularly limited, but a resin other than the base resin (A) or a part of the base resin (A) can be used.
As the carrier resin (CA), a polyolefin resin is preferable, and polyethylene is particularly preferable because it has a good affinity with the silanol condensation catalyst (X) and can impart heat resistance.

<Additives>
The outer insulating layer may contain various additives generally used in electric wires, electric cables, electric cords and the like as long as the effects of the present invention are not impaired. Examples of such additives include cross-linking aids, antioxidants, lubricants, metal deactivating agents, fillers (including flame-retardant (auxiliary) agents) and the like.

The antioxidant is not particularly limited, and examples thereof include an amine antioxidant, a phenol antioxidant, a sulfur antioxidant, and the like, and a phenol antioxidant is preferable. The antioxidant can be added in an amount of preferably 0.1 to 15.0 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the base rubber.

〔sheath〕
The sheath is made of a silanol condensed cured product of the silane crosslinkable composition J described later. By adopting the silane cross-linking method, the inner insulating layer and the outer insulating layer are not easily crushed because the chemical cross-linking tube is not exposed to high temperature and high pressure even when the sheath is formed. As a result, the peelability of the sheath is excellent. Further, the inner insulating layer and the outer insulating layer can maintain the same shape as the cross-sectional shape of the conductor. For example, when the cross section of the cable core is circular, the circular cross-sectional state can be maintained at the outer periphery of the conductor, and the inner insulating layer can be maintained. In addition, the peelability of the outer insulating layer can be made very excellent. Further, since excessive pressure is not applied to the inner insulating layer and the outer insulating layer when the sheath is extruded, the adhesion with the conductor can be controlled to be low, and the bending durability and the peeling property of the insulating layer can be excellent.
[Silane Crosslinkable Composition J]
1 to 200 parts by mass of the inorganic filler (Q) and 2 parts by mass of the silane coupling agent (F) grafted with the base resin (B) with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. Silane crosslinkable composition J containing 15.0 parts by mass or less and further containing a silanol condensation catalyst (Y).
The preferable content of each component in the silane crosslinkable composition J is the same as the blending amount of each component in the method for producing a cabtire cable having steps (k) to (n) described later, and the preferred range is also the same. be.
Hereinafter, the components of the silane crosslinkable composition J and the materials used for the preparation thereof will be described.

<Base resin (B)>
The base resin (B) contains a halogen-containing resin or a rubber-containing halogen-containing resin. The halogen-containing resin has the above-mentioned grafting reaction-capable site in the main chain or at the end thereof.

The halogen-containing resin is not particularly limited, and conventional halogen-containing resins or ordinary ones used in halogen-containing rubber compositions can be used.
As the halogen-containing resin, one type may be used alone or two or more types may be used in combination.

Examples of the halogen-containing resin include resins or rubbers containing halogen atoms in the main chain or side chains. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, and a fluorine atom or a chlorine atom is preferable. Examples of the halogen-containing resin include chlorine-containing resin or rubber containing a chlorine atom, fluororesin or rubber containing a fluorine atom, and the like.

Examples of the halogen-containing resin include polyvinyl chloride resin, chlorinated polyethylene resin, chloroprene rubber, sulfonated chloroprene rubber, resin or rubber composed of a copolymer of vinyl chloride and vinyl acetate, and a copolymer of vinyl chloride and urethane. Examples thereof include a chlorine-containing resin or rubber such as a resin or rubber, a material having a halogen atom, or a fluororesin or rubber such as fluororubber.
In addition, a copolymer of polyvinyl chloride, polyvinylidene chloride or a copolymer thereof, a copolymer of chlorinated polyethylene, a chlorine-containing resin or rubber such as chlorosulfonated rubber, and a fluororesin or rubber such as fluororesin. And so on.

As the chlorine-containing resin or rubber, a chlorinated polyethylene resin, a polyvinyl chloride resin or a copolymer of polyvinyl chloride is preferable.
The fluororubber is not particularly limited, but is limited to tetrafluoroethylene-propylene copolymer rubber (FEPM), tetrafluoroethylene-fluoride (for example, hexafluoro) propylene copolymer rubber, and tetrafluoroethylene-perfluoro. Examples thereof include vinyl ether copolymer rubber (FFKM), vinylidene fluoride rubber (FKM, for example, vinylidene fluoride-hexafluoropropylene copolymer rubber), or a copolymer rubber of these and a chlorine-based rubber, for example, chloroprene. ..

In the present invention, the halogen-containing resin is preferably a chlorine-containing resin or rubber, or a fluororesin or rubber, and more preferably a chlorine-containing resin or rubber.

The content of halogen atoms in the halogen-containing resin (mass ratio of halogen atoms to the total amount of halogen-containing resin, referred to as halogen content) is not particularly limited and can be appropriately set according to the purpose.

The base resin (B) may contain other resins, oil components and plasticizers in addition to the halogen-containing resin.
Other resins are not particularly limited, and examples thereof include thermoplastic elastomers and polyolefin resins. As the polyolefin resin, the one described in the above base resin (A) can be used.
The oil component is not particularly limited, and examples thereof include organic oil and mineral oil. Examples of the organic oil or mineral oil include soybean oil, paraffin oil, and naphthenic oil.
The plasticizer is not particularly limited, and examples thereof include various types of plasticizers usually used for halogen-containing resins or halogen-containing rubbers. Examples thereof include trialkyl (C8, C10) trimellitic acid, pyromellitic acid ester plasticizer, phthalate ester plasticizer, adipate plasticizer, polyester plasticizer and the like.

When the base resin (B) contains components other than the halogen-containing resin, each component is contained so that the total of each component such as the halogen-containing resin, other resins, oil components and plasticizers is 100% by mass. The rate is appropriately determined and preferably selected from the following range.
For example, the content of the halogen-containing resin in the base resin (B) is preferably 30 to 100% by mass, more preferably 50 to 100% by mass, still more preferably 50 to 89% by mass.
The oil content is not particularly limited, but is preferably 0 to 75% by mass, more preferably 0 to 60% by mass, based on 100% by mass of the base resin (B).
The content of the plasticizer is not particularly limited, but is preferably 0 to 75% by mass, more preferably 0 to 45% by mass, still more preferably 11 to 21% by mass in 100% by mass of the base resin (B).

The base resin (B) preferably contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer.

<Organic peroxide (D)>
As the organic peroxide (D), the organic peroxide (C) described in the above-mentioned [outer insulating layer] can be used. The same applies to the preferred range and the like.

<Inorganic filler (Q)>
As the inorganic filler (Q), the inorganic filler (P) described in the above-mentioned [outer insulating layer] can be used. The same applies to the preferred range and the like.
As the inorganic filler (Q), at least one of hydrotalcite, magnesium hydroxide, silica, and calcium carbonate is preferable.

<Silane coupling agent (F)>
The silane coupling agent (F) has a grafting reaction with the base resin (B) in the silane crosslinkable composition J. Similar to the silane coupling agent (E), a commercially available product may be used as the silane coupling agent (F) that has undergone a graft reaction with the base resin (B).
As the silane coupling agent (F), the silane coupling agent (E) described in the above-mentioned [outer insulating layer] can be used. The same applies to the preferred range and the like.

<Silanol condensation catalyst (Y)>
As the silanol condensation catalyst (Y), the silanol condensation catalyst (X) described in the above-mentioned [outer insulating layer] can be used. The same applies to the preferred range and the like.

<Carrier resin (CB)>
The carrier resin (CB) corresponds to the carrier resin (CA) described in the above-mentioned [outer insulating layer].
As the carrier resin (CB), a part of the base resin (B) can be used. The carrier resin (CB) is preferably chlorinated polyethylene and / or polyvinyl chloride. It is also preferable to use chloroprene rubber as the carrier resin (CB).

<Additives>
The sheath may contain the additives described in the above-mentioned [outer insulating layer] as long as the effects of the present invention are not impaired. The preferred range of additives and the like are the same as those described above.

The silane crosslinkable composition J can be prepared by the steps (k) and (l) described later.

[[Manufacturing method of cabtire cable and method of manufacturing insulated wire for cabtire cable]]
The method of manufacturing the cabtire cable of the present invention and the method of manufacturing the insulated wire for the cabtire cable will be described.
In the method for manufacturing an insulated wire for a cabtire cable of the present invention, the outer periphery of the conductor is coated with a polyolefin resin to form an inner insulating layer (1), and the outer periphery of the inner insulating layer is made of ethylene rubber and a styrene-based elastomer. The step (2) of forming the outer insulating layer by coating at least one of the above and curing at least one of the ethylene rubber and the styrene-based elastomer is performed.
Further, in the method for manufacturing a cabtire cable of the present invention, at least the above steps (1) and (2) are performed, and then the outer periphery of the obtained insulated wire is covered with a sheath (k) to (n). I do.

In the step (1), it suffices if the outer periphery of the conductor can be covered with the polyolefin resin, and the molding method and molding conditions are appropriately selected. Examples of the molding method include extrusion molding using an extruder, injection molding using an injection molding machine, and molding methods using other molding machines. In the present invention, extrusion molding in which a conductor and a polyolefin resin are coextruded is preferable. When extrusion molding is performed, it may be cooled in a water tank or the like after coating.
The step (1) can be performed according to a preferred form of the cabtire cable of the present invention. For example, when one conductor is used, the outer periphery of the conductor is coated with a polyolefin resin to form an inner insulating layer. When a plurality of conductors are used, the outer periphery of the aggregate of the plurality of conductors is coated with a polyolefin resin to form an inner insulating layer.

When the inner insulating layer contains a silanol condensed product obtained by the silane cross-linking method of the polyolefin resin, in step (1), the outer periphery of the conductor is coated with the silane graft polyolefin resin, and the silane graft polyolefin resin is cured with the silanol condensation catalyst. The step (1a) for forming the inner insulating layer is preferable. The coating and curing can be carried out by an ordinary method, and can be carried out in the same manner with reference to the case where the outer insulating layer is formed by the silane crosslinking method, which will be described later, except that the resin to be used and the target of the coating are different. ..

The method of coating the outer periphery of the inner insulating layer on at least one of the ethylene rubber and the styrene-based elastomer and the method of curing at least one of the ethylene rubber and the styrene-based elastomer in the step (2) can be performed by a usual method. .. The curing may be performed at the same time as the coating, or may be performed after the coating. The above curing may be carried out by a chemical cross-linking method or a silane cross-linking method.

The coating of at least one of the ethylene rubber and the styrene-based elastomer in the step (2) (arrangement of the inner insulating layer on the outer periphery) can be performed by the above-mentioned various molding methods, but is preferably performed by extrusion molding. From the viewpoint of adhering the outer insulating layer and the inner insulating layer and / or forming these layers at the same time, the coating has a temperature higher than the melting point of the polyolefin resin used for the inner insulating layer (preferably, the inner insulating layer). It is more preferable to carry out at the melting point of the polyolefin resin used in the above + (temperature of 20 to 100) ° C.). It is considered that the outer insulating layer and the inner insulating layer are adhered to each other by melting or softening the surface of the inner insulating layer.

After the coating in the step (2), it is preferable that the inner insulating layer is not heated to a temperature exceeding the melting point + 60 ° C. of the polyolefin resin contained in the inner insulating layer. Further, it is preferable not to be exposed to the temperature for a long time, for example, 10 seconds or longer, preferably 5 seconds or longer, and more preferably 3 seconds or longer. That is, it is preferable that the inner insulating layer is not heated to a temperature exceeding the melting point of the polyolefin resin + 60 ° C. for 10 seconds or more during the curing in the step (2) after the coating in the step (2).
In the present invention, "the inner insulating layer is not heated to a temperature exceeding the melting point + 60 ° C. of the polyolefin resin contained in the inner insulating layer" means that the inner insulating layer is at a temperature (high temperature) of + 60 ° C. or lower of the melting point of the polyolefin resin. In a temperature environment (for example, 160 to 220 ° C.) in which the melting point of the polyolefin resin exceeds the melting point of the above-mentioned polyolefin resin + 60 ° C. in an embodiment in which the steps (2) and subsequent steps are performed while being maintained at Degree) includes both aspects of the step (2) and subsequent steps. Here, the time that does not impair the effect of the present invention is not unique because it varies depending on changes in the type of polyolefin resin, the thickness of the inner insulating layer, the time until the cooling step, and the like, but for example, the entire inner insulating layer. It means the time that does not soften or melt. In the present invention, the heat applied to the inner insulating layer is easily transferred to the conductor, and usually, when the cooling step is performed after coating, the obtained insulated wire is promptly cooled in a water tank or the like after coating. The entire inner insulating layer is exposed to the above high temperature for a short period of time, and although the surface of the inner insulating layer is affected by heat due to heating during coating, the entire inner insulating layer is not softened or melted. it is conceivable that. The same applies to the sheath coating described later.
On the other hand, when a cured product is formed by chemical cross-linking, the insulated wire after extrusion molding is introduced into the cross-linked pipe or kiln and heated and pressurized for a relatively long time (several tens of seconds to several minutes). The whole is exposed to high temperature, and the whole inner insulating layer tends to be affected by heat, and the inner insulating layer tends to be easily deformed by pressure.

When at least one of the ethylene rubber and the styrene-based elastomer is cured by the electron beam cross-linking method, it can be performed as follows. For example, it can be carried out by a step of covering the outer periphery of the inner insulating layer with at least one of ethylene rubber and a styrene-based elastomer and irradiating it with an electron beam to crosslink it. As the conditions for electron beam cross-linking, the irradiation amount is usually preferably 5 to 40 Mrad.

When curing at least one of the ethylene rubber and the styrene-based elastomer by the chemical cross-linking method, it can be performed as follows. For example, a composition containing at least one of ethylene rubber and a styrene-based elastomer and an organic peroxide is prepared, the outer periphery of the inner insulating layer is covered with the composition, and the composition is heated to decompose the organic peroxide for chemistry. It can be carried out by a step of cross-linking. It may be pressurized at the time of heating.
The coating of the composition can be carried out by the above-mentioned various molding methods, but is preferably carried out by extrusion molding.
The heating conditions are not particularly limited as long as they are conditions under which the organic peroxide decomposes, but it is preferably heated to 130 to 220 ° C., and may be continuously heated and crosslinked after extrusion. It may be crosslinked. When pressurizing, it is preferable to apply a pressure of 1 to 3 atm.

From the viewpoint of curing at least one of the ethylene rubber and the styrene-based elastomer at a temperature of the melting point of the polyolefin resin + 60 ° C. or lower, it is preferable to perform the curing by the silane crosslinking method.

When the silane cross-linking method is adopted, it is more preferable that the step (2) is carried out by the following series of steps.
Step (2a): At least one of the ethylene rubber and the styrene-based elastomer and the silane coupling agent having a graft reaction site are melted in the presence of the organic peroxide at a temperature equal to or higher than the decomposition temperature of the organic peroxide. Step of mixing to prepare a silane master batch i containing a silane crosslinkable resin by reacting at least one of an ethylene rubber and a styrene-based elastomer with a grafting reaction portion of a silane coupling agent (2b): Silane master batch. Step of melt-mixing i and a silanol condensation catalyst to obtain a silane crosslinkable composition i (2c): Step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition i to form an outer insulating layer precursor. (2d): Step of contacting the outer insulating layer precursor with water to form the outer insulating layer In the above, the outer insulating layer precursor is the (molded) layer of the silane crosslinkable composition i. The outer insulating layer is a layer of a silanol condensed cured product of the silane crosslinkable composition i, and a layer of a cured product of the outer insulating layer precursor.

The steps (2a) to (2d) can be carried out in the same manner as the steps (a) to (d) described later, except that the blending amount is different from that of the component to be used. Since the inorganic filler is not used in the steps (2a) to (2d), the description related to the inorganic filler is not applied to the steps (2a) to (2d) in the description of the steps (a) to (d) described later.
In the step (2a), the blending amount of the silane coupling agent is preferably 2 to 15 parts by mass, more preferably 2.5 to 6 parts by mass, based on 100 parts by mass of the total of the ethylene rubber and the styrene-based elastomer.
In the step (2a), the blending amount of the organic peroxide is preferably 0.3 to 6 parts by mass, more preferably 0.5 to 2 parts by mass with respect to 100 parts by mass of the total of ethylene rubber and the styrene-based elastomer. ..

In this way, steps (2a) to (2d) are carried out, and an outer insulating layer containing at least one silanol condensed cured product of ethylene rubber and a styrene-based elastomer is formed on the outer periphery of the inner insulating layer. That is, an insulated wire having the specific outer insulating layer on the outer periphery of the inner insulating layer can be obtained.
In the silanol condensed cured product, the hydrolyzable group of the silane coupling agent bonded to the silane graft resin is crosslinked by silanol condensation on the silane graft resin obtained by grafting the silane coupling agent to the ethylene rubber or styrene-based elastomer. It was made to. This silane graft resin contains a crosslinked resin condensed via a silanol bond (siloxane bond).
Therefore, this cured product layer contains a crosslinked cured product of the silane graft resin. The crosslinked cured product of the silane graft resin has at least one of the ethylene rubber component and the styrene-based elastomer component, and the silane coupling agent component. The content of each component in the crosslinked cured product varies depending on the reaction conditions, the reaction rate, etc., but is preferably within the above range. More specifically, in this crosslinked cured product, the reaction sites of the silane coupling agent grafted on the silane graft resin are hydrolyzed and undergo a silanol condensation reaction with each other, whereby the silane graft resins are crosslinked with each other via the silane coupling agent. Contains at least the above silane crosslinked resin.

When the silane cross-linking method is adopted, it is more preferable that the step (2) is performed by the following steps (a) to (d).
Step (a): With respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer, 0.01 to 0.6 parts by mass of the organic peroxide (C) and an inorganic filler ( P) 1 to 400 parts by mass and 1 to 15.0 parts by mass of the silane coupling agent (E) having a grafting reaction site capable of crosslinking with the base resin (A) are melt-mixed and subjected to the grafting reaction. Step of preparing a silane master batch K containing a silane crosslinkable resin G by grafting the site with the base resin (A) Step (b): Melting and mixing the silane master batch K and the silane condensation catalyst (X). Step (c): A step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition I to form an outer insulating layer precursor Step (d): Outer insulating layer precursor The process of contacting the body with water to form an outer insulating layer

The steps (a) to (d) will be described.

In the step (a), the blending amount of the organic peroxide (C) is 0.01 to 0.6 parts by mass and 0.03 to 0.25 parts by mass with respect to 100 parts by mass of the base resin (A). The unit is preferable.

In the step (a), the blending amount of the inorganic filler (P) is 1 to 400 parts by mass, preferably 3 to 100 parts by mass with respect to 100 parts by mass of the base resin (A).

In the step (a), the blending amount of the silane coupling agent (E) is 1 to 15.0 parts by mass, preferably 1.5 to 8 parts by mass with respect to 100 parts by mass of the base resin (A). Further, 2 to 6 parts by mass is preferable.

In the step (b), the blending amount of the silanol condensation catalyst (X) is not particularly limited, and is preferably 0.01 to 0.4 parts by mass, more preferably 0.01 parts by mass with respect to 100 parts by mass of the base resin (A). It is 0.03 to 0.2 parts by mass.

In the step (a), the mixing order of each component is not particularly limited, and may be mixed in any order.
In the present invention, the entire base resin (A) can be melt-mixed in the step (a), but in the step (a), a part of the base resin (A) is melt-mixed and the rest is described later ( It is preferable to melt and mix in b).
In the present invention, each component can be melt-kneaded at once, but it is preferable to (melt) mix the above-mentioned components by the following steps (a-1) and (a-2).
Step (a-1): At least the inorganic filler (P) and the silane coupling agent (E) are mixed to prepare a mixture. Step (a-2): The mixture obtained in the step (a-1) and the mixture. A step of melt-mixing all or part of the base resin (A) in the presence of the organic peroxide (C) at a temperature equal to or higher than the decomposition temperature of the organic peroxide (C).

The method for mixing the inorganic filler (P) and the silane coupling agent (E) in the step (a-1) is not particularly limited, and examples thereof include a mixing method such as a wet treatment and a dry treatment. In the present invention, a dry treatment is preferable in which the silane coupling agent (E) is added to the inorganic filler (P), preferably the dried inorganic filler (P), with or without heating, and mixed. The silane coupling agent (E) premixed in this manner exists so as to surround the surface of the inorganic filler (P), and a part or all thereof is adsorbed or bonded to the inorganic filler (P). This makes it possible to reduce the volatilization of the silane coupling agent (E) during the melt mixing in the subsequent step (a-2). The mixing temperature is preferably 10 to 60 ° C., more preferably room temperature (25 ° C.), and can be set to a condition of about several minutes to several hours. For this mixing, a commonly used mixer, for example, the kneading device described in step (a-2) can be used.

In the mixing of the step (a-1), the organic peroxide (C) may be present. The method for mixing the organic peroxide (C) is not particularly limited, and may be present when the above mixture and the base resin (A) are melt-mixed. Further, the organic peroxide (C) may be mixed with other components or may be a simple substance.
In the mixing of the step (a-1), the base resin (A) may be present as long as the temperature lower than the decomposition temperature is maintained. In this case, it is preferable to mix the inorganic filler (P) and the silane coupling agent (E) together with the base resin (A) at the above temperature (step (a-1)) and then melt-mix them.

In the production method of the present invention, the obtained mixture, all or part of the resin, and the remaining components not mixed in the step (a-1) are then added to the mixture in the presence of the organic peroxide (C). While heating to a temperature equal to or higher than the decomposition temperature of the organic peroxide (C), the mixture is melt-kneaded (step (a-2)).
If the step (a-1) is not performed in the presence of the organic peroxide (C), the organic peroxide (C) is mixed in the step (a-2).

In the step (a-2), the temperature at which the above components are melt-mixed (also referred to as melt-kneading or kneading) is equal to or higher than the decomposition temperature of the organic peroxide, preferably the decomposition temperature of the organic peroxide (C) + (25). The temperature is ~ 110) ° C. This decomposition temperature is preferably set after the resin component has melted. At the above mixing temperature, the above components are melted, the organic peroxide (C) is decomposed and acts, and the necessary silane graft reaction proceeds sufficiently in the step (a-2). Other conditions, such as the mixing time, can be set as appropriate.
The mixing method is not particularly limited as long as it is a method usually used for rubber, plastic and the like. The mixing device is appropriately selected depending on, for example, the blending amount of the inorganic filler (P). As the kneading device, a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, various kneaders, or the like is used. A closed mixer such as a Banbury mixer or various kneaders is preferable in terms of the dispersibility of the resin component and the stability of the crosslinking reaction.
The mixing method of the base resin (A) is not particularly limited. For example, the base resin (A) may be prepared in advance and used, or each component, for example, a resin component such as ethylene rubber, a non-aromatic organic oil, or the like may be mixed separately.

In the present invention, when each of the above components is melt-mixed at once, the conditions for melt-mixing are not particularly limited, but the conditions of step (a-2) can be adopted. In this case, part or all of the silane coupling agent (E) is adsorbed or bonded to the inorganic filler (P) during melt mixing.

In the step (a), particularly the step (a-2), it is preferable to knead each of the above-mentioned components without substantially mixing the silanol condensation catalyst (X). As a result, the condensation reaction of the silane coupling agent (E) can be suppressed, melt mixing is easy, and a desired shape can be obtained during extrusion molding. Here, "substantially not mixed" does not exclude the silanol condensation catalyst that is inevitably present, and exists to the extent that the above-mentioned problem due to the silanol condensation of the silane coupling agent (E) does not occur. It means that you can do it. For example, in the step (a-2), the silanol condensation catalyst may be present as long as it is 0.01 part by mass or less with respect to 100 parts by mass of the base resin (A).

In the step (a), the blending amount of other resins and the additives that can be used in addition to the above components is appropriately set as long as the object of the present invention is not impaired.
In the step (a), the above-mentioned additives, particularly the antioxidant and the metal deactivating agent, may be mixed in any step or with the components, but the silane coupling agent (E) mixed with the inorganic filler (P). ) Is preferably mixed with the carrier resin in that it does not inhibit the graft reaction to the resin.
In step (a), particularly step (a-2), it is preferred that the cross-linking aid is substantially non-mixed. If the cross-linking aid is not substantially mixed, the organic peroxide (C) is unlikely to cause a cross-linking reaction between the resin components during the melt mixing, and the appearance is excellent. Further, the graft reaction of the silane coupling agent (E) to the base resin (A) is likely to occur, and the heat resistance becomes excellent. Here, the fact that they are not substantially mixed does not exclude the cross-linking aid that is inevitably present, and means that the cross-linking aid may be present to such an extent that the above-mentioned problems do not occur.

In this way, the step (a) is performed, and the base resin (A) and the silane coupling agent are grafted to synthesize a silane graft resin, and the silane master containing the silane graft resin as a reaction composition. Batch K (also referred to as silane MBK) is prepared. This silane MBK is a silane crosslinkable resin G (silane crosslinkable resin derived from the base resin (A)) in which the silane coupling agent (E) is grafted onto the base resin (A) to the extent that it can be molded by the step (c) described later. Also called).
In the above step (a), particularly in the upper step (a-1), the silane coupling agent binds or adsorbs to or adsorbs a chemically bonded site of the inorganic filler with its hydrolyzable silyl group. Further, this silane coupling agent is grafted with a site capable of a grafting reaction of ethylene rubber, a styrene elastomer or a polyolefin resin at the grafting reaction site thereof in the preparation step (a), particularly the step (a-2). Elastomer reacts. In the step (a), at least the following can be mentioned as an embodiment in which the silane coupling agent reacts with the base resin by grafting. That is, it is an embodiment in which the silane coupling agent bonded or adsorbed to the inorganic filler with a weak bond is desorbed from the inorganic filler and undergoes a grafting reaction with the base resin. Further, it is an embodiment in which the silane coupling agent bonded or adsorbed to the inorganic filler with a strong bond undergoes a grafting reaction with the base resin while maintaining the bond with the inorganic filler. Examples of the weak bond with the inorganic filler of the silane coupling agent include interaction by hydrogen bonding, interaction between ions, partial charges or dipoles, and action by adsorption. Further, examples of the strong bond with the inorganic filler include a chemical bond with a portion of the surface of the inorganic filler that can be chemically bonded.

In the production method of the present invention, the step (b) is then performed in which the silane MBK obtained in the step (a) and the silanol condensation catalyst (X) are melt-mixed.
In the step (b), when a part of the resin is melt-mixed in the above steps (a) (step (a-2)), the balance of the base resin (A) and the silanol condensation catalyst (X) are melt-mixed. , Catalyst master batch M (also referred to as catalyst MBM) is prepared and this catalyst MBM is used. In addition to the remainder of the base resin (A), another resin can also be used.

The mixing ratio of the balance of the base resin (A) as the carrier resin (CA) and the silanol condensation catalyst (X) is not particularly limited, but is preferably set so as to satisfy the blending amount in the step (a). Will be done. When the balance of the base resin (A) is blended in the step (b), the base resin (A) is preferably 80 to 99% by mass, more preferably 85 to 95% by mass in the step (a-2). It is blended, and in the step (b), preferably 1 to 20% by mass, more preferably 5 to 15% by mass.
The carrier resin (CA) and the silanol condensation catalyst (X) may be mixed by any method as long as they can be uniformly mixed, and examples thereof include mixing (melt mixing) performed under melting of the base resin (A). Melt mixing can be performed in the same manner as in the above step (a-2). For example, the mixing temperature can be 80 to 250 ° C, more preferably 100 to 240 ° C. Other conditions, such as the mixing time, can be set as appropriate.
The catalyst MBM thus prepared is a mixture of silanol condensation catalyst (X), carrier resin (CA) and optionally added filler.

On the other hand, when the entire base resin (A) is melt-mixed in the step (a-2), the silanol condensation catalyst (X) itself or the silanol condensation catalyst (X) is combined with another resin in the step (b). Use a mixture of. The mixing method of the other resin and the silanol condensation catalyst (X) is the same as that of the catalyst MBM.
The blending amount of the other resin is preferably 1 with respect to 100 parts by mass of the base resin (A) in that the graft reaction can be promoted in the step (a-2) and lumps are less likely to occur during molding. It is ~ 60 parts by mass, more preferably 2 to 50 parts by mass, still more preferably 2 to 40 parts by mass.

Inorganic fillers may be used in step (b). In this case, the blending amount of the inorganic filler is not particularly limited, but is preferably 350 parts by mass or less with respect to 100 parts by mass of the carrier resin (CA).

In the production method of the present invention, the silane MBK and the silanol condensation catalyst (X) (the silanol condensation catalyst (X) itself, the prepared catalyst MBM, or a mixture of the silanol condensation catalyst (X) and another resin) are used. Melt and mix. The mixture thus obtained is referred to as a silane crosslinkable composition I.
The melt-mixing method may be any method performed under the melting of the base resin, and is basically the same as the melting-mixing in step (a-2), for example. The melting temperature is appropriately selected depending on the melting temperature of the resin or the carrier resin (CA), and is, for example, preferably 80 to 250 ° C, more preferably 100 to 240 ° C. Other conditions, for example, the mixing (kneading) time can be set as appropriate.
In the step (b), in order to avoid the silanol condensation reaction, it is preferable that the silane MBK and the silanol condensation catalyst (X) are not kept in a high temperature state for a long time in a mixed state.
One aspect of the silane crosslinkable composition I is an inorganic filler (P) 1 to 400 with respect to 100 parts by mass of a base resin (A) containing a styrene-based elastomer and at least one of ethylene rubber and a non-aromatic organic oil. It contains 1 part by mass and 1 to 15.0 parts by mass of the silane coupling agent (E) grafted with the base resin (A), and further contains a silanol condensation catalyst (X).

In the present invention, the silane MBK and the silanol condensation catalyst (X) can be dry-blended before being melt-mixed. The method and conditions for dry blending are not particularly limited, and examples thereof include dry mixing in step (a-1) and the conditions thereof.

In the present invention, the above steps (a) and (b) can be mixed simultaneously or continuously.

In this way, the silane crosslinkable composition I, which is a melt-kneaded product of the silane MBK and the silanol condensation catalyst (X) (or the catalyst MBM), is obtained. The silane crosslinkable composition I contains a silane crosslinkable resin G and a silanol condensation catalyst. The silane crosslinkable composition I (silane crosslinkable resin G) is an uncrosslinked body in which the hydrolyzable silyl group derived from the silane coupling agent is not silanol-condensed. In practice, partial cross-linking (partial cross-linking) is unavoidable due to melt-kneading in the preparation step (b), but it is preferable that the moldability in the step (c) described later is maintained.

In the production method of the present invention, the step (c) is then performed by coating the outer periphery of the inner insulating layer with the silane crosslinkable composition I obtained in the step (b) to form the outer insulating layer precursor.
In the step (c), it is sufficient that the silane crosslinkable composition I can be coated on the inner insulating layer, and the molding method and molding conditions are appropriately selected. Examples of the molding method include extrusion molding using an extruder, injection molding using an injection molding machine, and molding using another molding machine. In the present invention, extrusion molding in which the conductor forming the inner insulating layer and the silane crosslinkable composition I are coextruded is preferable. In step (c), the inner insulating layer is not exposed to a temperature significantly higher than the melting point of the polyolefin resin forming the inner insulating layer (generally, the melting point of the polyolefin resin forming the inner insulating layer + 100 ° C. or less, preferably the inner insulating layer. It is preferably maintained at a temperature of + 60 ° C. or lower, which is the melting point of the polyolefin resin to be formed). In step (c), the surface of the inner insulating layer is melted by heating the inner insulating layer at a temperature equal to or higher than the melting point of the polyolefin resin forming the inner insulating layer (for example, the melting point of the polyolefin resin forming the inner insulating layer + 60 ° C.). Alternatively, it is more preferable to soften it.

Further, the step (c) can be carried out simultaneously with or continuously of the step (b). For example, a series of steps can be adopted in which a silane masterbatch and a silanol condensation catalyst (or a catalyst masterbatch) are melt-kneaded in a coating device, and then extruded and coated on the outer periphery of the inner insulating layer for molding.

In the method for manufacturing a cabtire cable of the present invention, the step (d) of bringing the outer insulating layer precursor (uncrosslinked body) obtained in the step (c) into contact with water is performed. As a result, the hydrolyzable group of the silane coupling agent (E) is hydrolyzed to silanol, and the hydroxyl groups of silanol are condensed with each other by the silanol condensation catalyst (X) present in the silane crosslinkable composition I. A cross-linking reaction takes place. In this way, the outer insulating layer (the layer of the silanol condensed cured product of the silane crosslinkable composition I) crosslinked with the outer insulating layer precursor can be formed on the outer periphery of the inner insulating layer.

Step (d) can be performed by a usual method. The above condensation reaction proceeds only by storing at room temperature in the presence of a silanol condensation catalyst. Therefore, in step (d), it is not necessary to positively contact the outer insulating layer precursor with water. In order to promote this cross-linking reaction, the outer insulating layer precursor can also be brought into contact with moisture. For example, it is possible to adopt a method of actively contacting with water, such as flooding with hot water, putting into a moist heat tank, or exposing to high-temperature steam. Further, at that time, pressure may be applied to allow water to permeate into the inside.

In this way, steps (a) to (d) are carried out, and an outer insulating layer made of a silanol condensed cured product of the silane crosslinkable composition I is formed on the outer periphery of the inner insulating layer. That is, an insulated wire having the specific outer insulating layer on the outer periphery of the inner insulating layer can be obtained.
The silanol condensate cured product of the silane crosslinkable composition I contains a silane graft resin obtained by grafting a specific amount of a silane coupling agent with a base resin containing an ethylene rubber or a styrene-based elastomer, and a specific amount of an inorganic filler. The silane crosslinkable composition is obtained by cross-linking the hydrolyzable group of the silane coupling agent bonded to the silane graft resin by silanol condensation. This silane graft resin contains a crosslinked resin condensed via a silanol bond (siloxane bond), and the inorganic filler may be bonded to the silane coupling agent of the silane graft resin.
Therefore, this cured product layer contains a crosslinked cured product of the silane graft resin and an inorganic filler. The crosslinked cured product of the silane graft resin has a base resin component (ethylene rubber component, styrene-based elastomer component, polyolefin component), an inorganic filler component, and a silane coupling agent component. The content of each component in the crosslinked cured product varies depending on the reaction conditions, the reaction rate, etc., but is preferably within the above range. More specifically, this crosslinked cured product is composed of a crosslinked resin in which a silane graft resin is bonded or adsorbed to an inorganic filler by a silane coupling agent and then bonded (crosslinked) via the inorganic filler and a silane coupling agent, and a silane graft. The reaction sites of the silane coupling agent grafted on the resin are hydrolyzed and undergo a silanol condensation reaction with each other, so that the silane graft resins include at least a silane crosslinked resin in which the silane graft resins are crosslinked via the silane coupling agent. Further, the cross-linked resin and the silane cross-linked resin may have a mixture of bonding (cross-linking) via an inorganic filler and a silane coupling agent and cross-linking via a silane coupling agent, respectively.
As described above, the insulated wire of the present invention can be manufactured.

In the method for manufacturing a cabtire cable of the present invention, a step of forming a sheath covering the outer periphery of the insulated wire is further performed. By this step, a sheath is coated on the outer periphery of the insulated wire (cable core), and the cabtire cable of the present invention can be obtained.
When a plurality of insulated wires are used, a step of arranging or twisting the plurality of insulated wires may be included before the above step.

The sheath is formed by the following steps (k) to (n).
Step (k): 0.003 to 0.3 parts by mass of the organic peroxide (D) and 1 to 200 parts by mass of the inorganic filler (Q) with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. A part and 15.0 parts by mass or less of the silane coupling agent (F) having a grafting reaction site capable of performing a grafting reaction with the base resin (B) are melt-mixed to form a grafting reaction site. Step of preparing a silane master batch L containing a silane crosslinkable resin derived from the base resin (B) by grafting with the base resin (B) Step (l): Silane master batch L and a silane condensation catalyst (Y) ) To obtain a silane crosslinkable composition J Step (m): A step of covering the outer periphery of the insulated wire with the silane crosslinkable composition J to form a sheath precursor Step (n): Sheath precursor Steps of contacting the body with water to form a sheath Steps (k) to (n) may be carried out in the same manner as in steps (a) to (d) except that the materials used, the blending amount thereof and the like are different. The same applies to the preferred embodiments that can be performed.
Hereinafter, the steps (k) to (n) will be described focusing on the differences from the steps (a) to (d).
In the above, the sheath precursor is a layer of the silane crosslinkable composition J. The sheath is a layer of a silanol condensed cured product of the silane crosslinkable composition J, and is a cured product of a sheath precursor.

In the step (k), the blending amount of the organic peroxide (D) is 0.003 to 0.3 parts by mass and 0.01 to 0.15 parts by mass with respect to 100 parts by mass of the base resin (B). The unit is preferable.

In the step (k), the blending amount of the inorganic filler (Q) is 1 to 200 parts by mass, preferably 3 to 60 parts by mass with respect to 100 parts by mass of the base resin (B). The inorganic filler (Q) preferably contains 2 parts by mass or more of silica with respect to 100 parts by mass of the base resin (B). The upper limit of the blending amount of silica is not particularly limited as long as it is within the range of the blending amount of the inorganic filler (Q), but 80 parts by mass or less is preferable with respect to 100 parts by mass of the base resin (B).

In the step (k), the mixing amount of the silane coupling agent (F) is more than 2 parts by mass and 15.0 parts by mass or less with respect to 100 parts by mass of the base resin (B), and is 1.5 to 8 parts by mass. The unit is preferable.

In the step (l), the blending amount of the silanol condensation catalyst (Y) is not particularly limited, and is preferably 0.01 to 0.25 parts by mass, more preferably 0.01 to 0.25 parts by mass with respect to 100 parts by mass of the base resin (B). It is 0.02 to 0.2 parts by mass.

The preparation of the silane masterbatch L in the step (k) is performed except that the base resin (B), the organic oxide (D), the inorganic filler (Q), and the silane coupling agent (F) are used in the above blending amounts. , Can be carried out in the same manner as the preparation of the silane masterbatch K in the above step (a).
Similar to the step (a), the entire base resin (B) can be melt-mixed in the step (k), but in the step (k), a part of the base resin (B) is melt-mixed and the rest is described later. It is preferable to melt and mix in the step (b).
The melt mixing in step (k) is preferably performed with a closed mixer.
Similar to the step (a), in the step (k), the inorganic filler (Q) is preferably used by mixing with the silane coupling agent (F). That is, in the present invention, it is preferable that each of the above components is (melted) mixed by the following steps (k-1) and (k-2).
Step (k-1): At least the inorganic filler (Q) and the silane coupling agent (F) are mixed to prepare a mixture. Step (k-2): The mixture obtained in the step (k-1) and the mixture. Step of melt-mixing all or part of the base resin (B) in the presence of the organic peroxide (D) at a temperature equal to or higher than the decomposition temperature of the organic peroxide (D). Step (k-1) And (k-2) can be performed in the same manner as in the above steps (a-1) and (a-2).
Here, when the balance of the base resin (B) is blended in the step (l), the base resin (B) is preferably 80 to 99% by mass, more preferably 85 to 95 in the step (k-2). By mass% is blended, and in step (l), preferably 1 to 20% by mass, more preferably 5 to 15% by mass is blended.
In the above step (k-1), it is preferable to mix the organic peroxide (D) in addition to the inorganic filler (Q) and the silane coupling agent (F).

In the step (k), a silane graft resin is synthesized by subjecting the base resin (B) and the silane coupling agent (F) to a grafting reaction, and the silane masterbatch L containing the silane graft resin as a reaction composition. (Also referred to as silane MBL) is prepared. This silane MBL is a silane crosslinkable resin H (silane crosslinkable resin derived from the base resin (B)) in which the silane coupling agent (F) is grafted onto the base resin (B) to the extent that it can be molded by the step (m) described later. Also called).

In the melt mixing of the silane master batch L and the silanol condensation catalyst (Y) in the step (l), the silane master batch K and the silanol condensation catalyst (X) in the step (b) are used, and the silane master batch L and the silanol condensation catalyst (Y) are mixed. It can be carried out in the same manner as in the above step (b) except that it is replaced with.
In the step (l), as in the step (b), the silanol condensation catalyst (Y) is preferably a catalyst MBN and is preferably mixed with the silane MBL.
Step (l) gives the silane crosslinkable composition J, which is a melt mixture of the silane MBL and the silanol condensation catalyst (Y) (or the condensation catalyst MBN). This silane crosslinkable composition J (silane crosslinkable resin) is an uncrosslinked body in which the hydrolyzable silyl group derived from the silane coupling agent is not silanol-condensed.
In one aspect of the silane crosslinkable composition J, 100 parts by mass of the base resin (B) containing a halogen-containing resin was grafted with 1 to 200 parts by mass of the inorganic filler (Q) and the base resin (B). The silane coupling agent (F) contains more than 2 parts by mass and 15.0 parts by mass or less, and further contains a silane crosslinkable composition J containing a silanol condensation catalyst (Y).

In the step (m), the silane crosslinkable composition J obtained in the step (l) is used to coat the outer periphery of the outer insulating layer of the insulated wire to form a sheath precursor. The step (m) can be carried out in the same manner as in the step (c) except that the silane crosslinkable composition I and the inner insulating layer in the step (c) are replaced with the silane crosslinkable composition J and the insulated wire, respectively. In step (m), a sheath precursor is formed on the outer periphery of the outer insulating layer of the insulated wire in place of the outer insulating layer precursor in step (c). In the step (m), the inner insulating layer is heated at a temperature equal to or higher than the melting point of the polyolefin resin forming the inner insulating layer (for example, the melting point of the polyolefin resin forming the inner insulating layer + 60 degrees) to melt the surface of the inner insulating layer. Alternatively, it is preferable to soften it.
In the step (m), specifically, the silane crosslinkable composition J is formed on the outer periphery of the outer insulating layer of the insulated wire, and preferably extruded to form a sheath precursor.
The step (m) is a step of coating the outer periphery of the cable core with the silane crosslinkable composition J, and the cable core is selected and used according to a preferable form of the cabtire cable of the present invention. For example, when a single insulated wire is used (see FIG. 1), the outer periphery of the insulated wire is coated with the silane crosslinkable composition J to form a sheath precursor. When a plurality of insulated wires are used (see FIG. 2), the outer periphery of the aggregate of the plurality of insulated wires is coated with the silane crosslinkable composition J to form a sheath precursor.

In the step (n), the sheath precursor obtained in the step (m) is brought into contact with water and crosslinked. The step (n) can be performed in the same manner as in the step (d) except that the outer insulating layer precursor of the step (d) is replaced with the sheath precursor. By step (n), a sheath is obtained on the outer periphery of the outer insulating layer, that is, the outer periphery of the insulated wire, instead of the outer insulating layer in step (d).

In this way, steps (k) to (n) are carried out, and a sheath made of a silanol condensed cured product of the silane crosslinkable composition J is formed on the outer periphery of the insulated wire.
The silanol condensate cured product of the silane crosslinkable composition J has a silane crosslinkability containing a silane graft resin obtained by grafting a specific amount of a silane coupling agent with a base resin containing a halogen-containing resin and a specific amount of an inorganic filler. The composition is obtained by cross-linking the hydrolyzable group of the silane coupling agent bonded to the silane graft resin by silanol condensation. This silane graft resin contains a crosslinked resin condensed via a silanol bond (siloxane bond), and the inorganic filler may be bonded to the silane coupling agent of the silane graft resin.

When the cabtire cable of the present invention is manufactured by the steps (1) and (2) (steps (a) to (d)) and steps (k) to (n), the steps (1) and (2) It is preferable to continuously perform the steps (k) to (n) after performing the steps (a) to (d). Here, "continuously" means that the order of the processes may be continuous, and each process does not have to be continuous in terms of time or the like, and may be performed at different places. For example, the insulated wire having the outer insulating layer formed in the steps (1) and (2) (steps (a) to (d)) may be stored in a warehouse and later covered with a sheath to form a cabtire cable. .. The same applies to the relationship between each consecutive process.

The cabtire cable of the present invention has excellent bending durability, excellent peeling property of an insulating layer, and peeling property of a sheath. The reason is not clear, but it can be considered as follows.
In the insulated wire of the present invention, the inner insulating layer and the conductor are formed by using a polyolefin resin for the inner insulating layer and having an outer insulating layer containing at least one cured product of ethylene rubber and a styrene-based elastomer on the outer periphery thereof. It is considered that the adhesive force between the two is not stronger than necessary, and the inner insulating layer has a certain degree of slipperiness with respect to the conductor. As a result of the cabtire cable of the present invention having such an insulated wire covered with a sheath, the conductor is unlikely to be broken even if it is repeatedly bent many times. Further, when the insulating layer is peeled off, the adhesive force between the inner insulating layer and the outer insulating layer is higher than the adhesive force between the separator and the outer insulating layer made of paper or the like, so that the inner insulating layer and the outer insulating layer are adhered to each other. It is considered that whiskers are less likely to occur on the cut end face of the insulating layer because the outer insulating layer is a cured product and excessive elongation of the insulating layer is suppressed. Furthermore, since the sheath is made of a specific silanol condensed cured product, excessive elongation of the sheath is suppressed to prevent whiskers from forming on the cut end face, and excessive tightening to the insulated wire is suppressed to form an outer insulating layer. Even if a mold release agent layer containing a mold release agent is not provided between the sheath and the sheath, the sheath can be satisfactorily peeled by the peeling process. In a normal cabtire cable, a mold release agent containing talc, metal soap, silicone, etc. is applied to the interface between the outer insulating layer and the sheath to reduce the adhesion between the outer insulating layer and the sheath. Therefore, the peelability of the sheath is improved. On the other hand, in the cabtire cable of the present invention, these mold release formulations may be applied, but high peelability of the sheath is ensured without applying a mold release agent between the outer insulating layer and the sheath. can.
As described above, the insulated wire of the present invention can be suitably used for the above-mentioned cabtire cable.

Further, in a preferred embodiment in which the outer insulating layer is directly coated on the outer periphery of the inner insulating layer, the inner insulating layer and the outer insulating layer are appropriately in close contact with each other, so that the peelability is more excellent.
Further, in a preferred embodiment in which the outer insulating layer is formed by silane cross-linking, unlike the case of chemical cross-linking, excessive tightening of the outer insulating layer on the inner insulating layer and melting of the inner insulating layer are suppressed, so that the conductor and the inner layer are suppressed. It is superior in slipperiness with the insulating layer. Therefore, the bending durability can be further improved. Further, in a preferred embodiment in which silane cross-linking is performed using the silane cross-linking composition I using an inorganic filler, the cross-linking of the outer insulating layer becomes more complicated, and the flexibility and toughness of the outer insulating layer are further enhanced. Conceivable. As a result, bending durability can be further improved.
Normally, the rubber-based insulating layer of a cabtire cable and the chemical cross-linking of the sheath are performed under high temperature and high pressure of about 150 to 230 ° C. Therefore, the insulated wire having a polyolefin resin layer as the inner insulating layer is made of a polyolefin resin by the above chemical cross-linking. Was not used in cabtyre cables because it melted and could not maintain layering. However, according to a preferred embodiment of the present invention in which the cross-linking method of the outer insulating layer is a silane cross-linking method, the polyolefin resin layer can be maintained in a layered state, and the slipperiness between the conductor and the outer insulating layer melts the polyolefin resin. It is expensive in some cases and can be suitably used for cabtire cables.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.
In Table 1, the numerical values relating to the blending amount of each example represent parts by mass unless otherwise specified.

The examples and comparative examples were carried out using the following components with their respective specifications set under the conditions shown in Table 1, and the evaluation results described later are also shown in Table 1.

The following compounds were used as each component shown in Table 1.

－－Component for inner insulating layer －－
"NUC7540" as a polyolefin resin (trade name, manufactured by Nippon Unicar Co., Ltd., linear low density polyethylene (LLDPE))
"UBEC-180" (trade name, manufactured by Ube Maruzen Petrochemical Co., Ltd., medium density polyethylene "HIZEX 5305" (trade name, manufactured by Prime Polymer Co., Ltd., high density polyethylene))
"PB222A" (trade name, manufactured by SunAllomer Ltd., random polypropylene)
"NUC6520" (trade name, manufactured by Nippon Unicar Co., Ltd., ethylene ethyl acrylate copolymer (EEA))
"Ganpishi" as a separator for comparison (generic name, manufactured by Goto Paper Industry Co., Ltd., paper, thickness: 30 μm)
"PET tape" (generic name, manufactured by Sanyu Kako Co., Ltd., polyethylene terephthalate, thickness: 20 μm)

－－Component for outer insulating layer －－
<Base resin (A)>
"Mitsui 3092EPM" as ethylene rubber (trade name, manufactured by Mitsui Chemicals, ethylene-propylene-diene rubber (EPDM))
"EP21P" (trade name, manufactured by JSR, ethylene-propylene-diene rubber (EPDM))
As a styrene-based elastomer, "Septon 4077" (trade name, manufactured by Kuraray, styrene-based elastomer (SEEPS))
"Diana Process PW90" as a non-aromatic organic oil (trade name, manufactured by Idemitsu Kosan Co., Ltd., paraffin oil)
As a polyolefin resin, "Evolu SP0540" (trade name, manufactured by Prime Polymer Co., Ltd., linear metallocene polyethylene (LLDPE))
"PB222A" (trade name, manufactured by SunAllomer Ltd., random polypropylene)
"UE320" (manufactured by Japan Polyethylene Corporation, Novatec PE (trade name), linear low density polyethylene (LLDPE))
"EV360" (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd., ethylene-vinyl acetate copolymer (EVA))
"NUC7540" (trade name, manufactured by Nippon Unicar Co., Ltd., linear low density polyethylene (LLDPE))
"NUC6520" (trade name, manufactured by Nippon Unicar Co., Ltd., ethylene ethyl acrylate copolymer (EEA))

<Organic peroxide (C)>
"Perhexa 25B" (trade name, manufactured by NOF CORPORATION, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, decomposition temperature 149 ° C)
"Park Mill D" (trade name, manufactured by NOF CORPORATION, dicumyl peroxide, decomposition temperature 151 ° C)
<Inorganic filler (P)>
Magnesium hydroxide (trade name: Kisma 5, manufactured by Kyowa Chemical Industry Co., Ltd., average particle size 0.8 μm)
Silica (Product name: Aerosil 200, manufactured by Nippon Aerosil)
<Silane coupling agent (E)>
"KBM-1003" (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., vinyltrimethoxysilane)
<Silanol condensation catalyst (X)>
"ADEKA STUB OT-1" (Product name, manufactured by ADEKA, Dioctyl tin laurylate)
<Antioxidant (Hinderdphenol Antioxidant)>
"Irganox 1076" (trade name, manufactured by BASF, phenol antioxidant, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate)
"Irganox 1010" (trade name, manufactured by BASF, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate])

－－Ingredients for sheath －－
<Base resin (B)>
"Eraslen 401A" as a halogen-containing resin (trade name, manufactured by Showa Denko, chlorinated polyethylene)
"Eraslen 402NA-X5" (trade name, manufactured by Showa Denko, chlorinated polyethylene)
"Skype Ren E-33" (trade name, manufactured by Tosoh Co., Ltd., chloroprene rubber)
"ZEST 1400" (trade name, manufactured by Shin-Daiichi PVC Co., Ltd., polyvinyl chloride (PVC))
As a plasticizer, "ADEKA SIZER C-9N" (trade name, manufactured by ADEKA, trimellitic acid-based plasticizer)
<Organic peroxide (D)>
"Perhexa 25B" (trade name, manufactured by NOF CORPORATION, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, decomposition temperature 149 ° C)
"Park Mill D" (trade name, manufactured by NOF CORPORATION, dicumyl peroxide, decomposition temperature 151 ° C)
<Inorganic filler (Q)>
"DHT4A" (trade name, manufactured by Kyowa Chemical Industry Co., Ltd., hydrotalcite)
"Kisma 5L" (trade name, manufactured by Kyowa Chemical Industry Co., Ltd., silane coupling agent pretreated magnesium hydroxide)
"Crystalite 5X" (trade name, manufactured by Ryumori Co., Ltd., crystalline silica)
"Softon 2200" (trade name, manufactured by Bikita Powder Industry Co., Ltd., calcium carbonate)
"Aerosil 200" (trade name, manufactured by Nippon Aerosil, hydrophilic fumed silica, amorphous silica)
<Silane coupling agent (F)>
"KBM-1003" (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., vinyltrimethoxysilane)
<Antioxidant (Hinderdphenol Antioxidant)>
"Irganox 1010" (trade name, manufactured by BASF, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate])
<Silanol condensation catalyst (Y)>
"ADEKA STUB OT-1" (Product name, manufactured by ADEKA, Dioctyl tin laurylate)

Insulation compound A
The organic peroxide and the silane coupling agent are mixed in the blending amounts shown in Table 1, the obtained mixture is added to the inorganic filler, and the mixture is stirred at 30 ° C. for 10 minutes using a Henshell mixer to prepare the inorganic filler mixture. Was prepared. Next, this inorganic filler mixture was added to a Banbury mixer together with a base resin (ethylene rubber, styrene elastomer, non-aromatic organic oil, and polyolefin resin), kneaded at 190 ° C. for 10 minutes, and discharged at 200 ° C. , Silane masterbatch (insulation compound A) was obtained (step (a)). After discharging, pellets were obtained by hot cutting via a feeder luder.

Insulation compound B
Add the base resin (polyethylene resin), silanol condensation catalyst, and antioxidant to the Banbury mixer at the blending amounts shown in Table 1, knead at 180 ° C for 10 minutes, discharge at 190 ° C, and discharge the catalyst MB (insulation compound). B) was obtained (step (b)). After discharging, pellets were obtained by hot cutting via a feeder luder.

Insulation compound C
A base resin (ethylene rubber and polyolefin resin), an organic peroxide, an antioxidant, and a silane coupling agent are introduced into a Henshell mixer at the blending amounts shown in Table 1, and the resin is stirred at 30 ° C. for 10 minutes. A mixture was prepared. Next, this resin mixture was added to a uniaxial strainer having a diameter of 90 mm, discharged from an extruder at a temperature of 190 ° C., the strands were water-cooled, water was removed, and the pellets were cut with a round pelletizer to obtain pellets.

Insulation compound D
The base resin (polyolefin resin), organic peroxide, antioxidant, and silane coupling agent are mixed in the blending amounts shown in Table 1, and the resin mixture is stirred at 30 ° C. for 10 minutes using a tumbler to obtain a resin mixture. Prepared. Next, this resin mixture was introduced into a single-screw extruder with a diameter of 65 mm (cylinder temperature 190 ° C., head temperature 200 ° C.), extruded into strands, cooled, and then cut with a round pelletizer. Pellets were obtained.

Sheath compound A
The organic peroxide and the silane coupling agent are mixed in the blending amounts shown in Table 1, the obtained mixture is added to the inorganic filler component, and the mixture is stirred at 30 ° C. for 10 minutes using a Henchel mixer to prepare the inorganic filler mixture. Was prepared. Next, this inorganic filler mixture was added to a Banbury mixer at a mass ratio shown in Table 1 together with a base resin (chlorinated polyethylene, chloroprene rubber, and polyvinyl chloride) and a plasticizer, and kneaded at 180 ° C. for 10 minutes. Discharge at 195 ° C. to obtain a silane masterbatch (sheath compound A) (step (k)). After discharging, pellets were obtained by hot cutting via a feeder luder.

Sheath compound B
Add the base resin (chlorinated polyethylene and polyvinyl chloride), plasticizer, silanol condensation catalyst, and antioxidant to the Banbury mixer at the blending amounts shown in Table 1, knead at 180 ° C for 10 minutes, and knead at 190 ° C. It was discharged to obtain a catalyst MB (sheath compound B) (step (l)). After discharging, pellets were obtained by hot cutting via a feeder luder.

Sheath compound C
Add organic peroxide, base resin (chlorinated polyethylene and chloroprene rubber), inorganic filler, and silane coupling agent to the kneader in the blending amounts shown in Table 1, knead at a maximum temperature of 100 ° C for 8 minutes, and knead at 100 ° C. It was discharged to obtain sheath compound C. After discharging, the ribbon was obtained by passing it through a roll and applying stearic acid.

Examples 1 to 13
As described below, an insulated wire having the configuration shown in FIG. 3 was manufactured except that a stranded wire was used as a conductor, and a cabtire cable having the configuration shown in FIG. 2 was manufactured using the insulated wire.
-Manufacturing of insulated wires-
The polyolefin resin shown in Table 1 is extruded and coated on the outside of a 37 / 0.26 conductor (outer diameter 1.8 mm) with an extruder of L / D 23 mm and a diameter of 25 mm to an outer diameter of 2.1 mm, and an inner insulating layer is attached. Formed a conductor.
In Examples 1 to 11, the insulating compounds A and B were dry-blended at room temperature (25 ° C.) at the blending ratio shown in Table 1, and the dry blended product was set to a cylinder temperature of 165 ° C. and a head temperature of 190 ° C. It was introduced into an extruder having a diameter of 65 mm, and the outer periphery of the conductor with the inner insulating layer was extruded and coated so as to have an outer diameter of 3.5 mm (step (c)). The obtained coated conductor was left at room temperature (25 ° C.) for 4 days (step (d)). In this way, the outer insulating layer was formed by the silane crosslinking method to obtain an insulated wire.
For Examples 12 and 13, the compound C was introduced into an extruder having a diameter of 75 mm for rubber set to 90 ° C. at the head temperature (oil temperature), and the outer circumference of the conductor with the inner insulating layer was set to an outer diameter of 3.5 mm. After extruding and coating so as to be, an insulated wire was obtained by continuously passing through a cross-linked tube heated with steam at 200 ° C. and 1.2 atm and cooling.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Next, the sheath compounds A and B were dry-blended at room temperature at the blending ratios shown in the table, and the dry blend was introduced into an extruder having a cylinder temperature of 130 ° C. and a head temperature of 150 ° C. and introduced into an extruder having a diameter of 90 mm. The outer periphery of the core was extruded and coated (standard wall thickness 0.8 mm) (step (m)) and left at room temperature for 4 days (step (n)). In this way, a sheath was formed by the silane cross-linking method to obtain a cabtire cable having an outer diameter of 11.2 mm. For some samples, talc was applied on the outer circumference of the cable core, and then a sheath was formed to obtain a cabtire cable (for those coated with talc, "Yes" is displayed in the talc application column of Table 1. Notated and shown.)

Comparative Examples 1 and 2
-Manufacturing of insulated wires-
Insulation compounds A and B were dry-blended at room temperature at the blending ratios shown in Table 1, and the dry blend was introduced into an extruder having a diameter of 65 mm set at a cylinder temperature of 165 ° C and a head temperature of 190 ° C, and 37/0. The outer circumference of the .26 conductor (outer diameter 1.8 mm) was extruded and coated so as to have an outer diameter of 3.5 mm. At the time of coating, the dry blend was extruded while attaching ganpishi or PET tape to the outer circumference of the conductor. The obtained coated conductor was left at room temperature for 4 days. In this way, an insulating layer was formed by the silane crosslinking method to obtain an insulated wire.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Next, the sheath compounds A and B were dry-blended at room temperature at the blending ratios shown in the table, and the dry blend was introduced into an extruder having a cylinder temperature of 130 ° C. and a head temperature of 150 ° C. and introduced into an extruder having a diameter of 90 mm. The outer periphery of the core was extruded and coated (standard wall thickness 0.8 mm) (step (m)) and left at room temperature for 4 days (step (n)). In this way, a sheath was formed by the silane cross-linking method to obtain a cabtire cable having an outer diameter of 11.2 mm.

Comparative Examples 3, 4, 6
-Manufacturing of insulated wires-
Insulation compounds A and B were dry-blended at room temperature at the blending ratios shown in Table 1, and the dry blend was introduced into an extruder having a diameter of 65 mm set at a cylinder temperature of 165 ° C and a head temperature of 190 ° C, and 37 / The outer circumference of the 0.26 conductor (outer diameter 1.8 mm) was extruded and coated so as to have an outer diameter of 3.5 mm. The obtained coated conductor was left at room temperature for 4 days. In this way, an insulating layer was formed by the silane crosslinking method to obtain an insulated wire.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Next, the sheath compound C was introduced into a chemical cross-linking extruder having a diameter of 90 mm and the cylinder temperature was set to 80 ° C. By passing it continuously, a sheath was formed by a chemical cross-linking method, and a cabtire cable was obtained. In Comparative Examples 3 and 6, a cabtire cable was created after applying talc on the outer periphery of the cable core.

Comparative Example 5
-Manufacturing of insulated wires-
Insulation compound C was introduced into a chemical cross-linking extruder with a diameter of 90 mm set to a cylinder temperature (oil temperature) of 110 ° C., and the outer circumference of the conductor of 37 / 0.26 conductor (outer diameter 1.8 mm) was 3.5 mm in outer diameter. It was extruded and coated so as to be. Then, it was continuously passed through a steam cross-linking device set at 200 ° C. and 1.2 atm to obtain a cross-linked rubber insulated wire by a chemical cross-linking method.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Talc was applied on the outer circumference of the cable core.
Next, the sheath compounds A and B were dry-blended at room temperature at the blending ratios shown in the table, and the dry blend was introduced into an extruder having a diameter of 90 mm set at a cylinder temperature of 130 ° C. and a head temperature of 150 ° C. The outer circumference of the cable core coated with talc was covered with an outer diameter of 11.2 mm, and left at room temperature for 4 days. In this way, a sheath was formed by the silane cross-linking method to obtain a cabtire cable.

Comparative Example 7
-Manufacturing of insulated wires-
An extruder with a diameter of 75 mm for rubber in which the insulation compound C is set to 90 ° C. at the head temperature (oil temperature), and the outer diameter of the outer circumference of the conductor of 37 / 0.26 conductor (outer diameter 1.8 mm) is 3.5 mm. It was extruded and coated so as to be. Then, a crosslinked rubber insulated wire was obtained by a chemical crosslinking method by continuously passing through a crosslinking tube heated with steam at 200 ° C. and 1.2 atm and cooling.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Talc was applied on the outer circumference of the cable core.
Next, the sheath compound C was introduced into a chemical cross-linking extruder having a diameter of 90 mm and the cylinder temperature was set to 80 ° C., and the outer circumference of the cable core coated with talc was extruded and coated so as to have an outer diameter of 11.2 mm, and then 200 ° C. A sheath was formed by a chemical cross-linking method by continuously passing it through a steam cross-linking device set in 1 to obtain a cabtire cable.

Comparative Examples 8 and 9
-Manufacturing of insulated wires-
The polyolefin resin shown in Table 1 is extruded and coated on the outside of a 37 / 0.26 conductor (outer diameter 1.8 mm) with an extruder of L / D 23 mm and a diameter of 25 mm to an outer diameter of 2.1 mm, and an inner insulating layer is attached. Formed a conductor.
The insulating compound D was introduced into an extruder for chemical cross-linking having a diameter of 90 mm set at a cylinder temperature of 120 ° C., and the outer periphery of the conductor with an inner insulating layer was extruded and coated so as to have an outer diameter of 3.5 mm. Then, it was continuously passed through a steam cross-linking device set at 200 ° C. and 1.2 atm to obtain a cross-linked insulated wire by a chemical cross-linking method.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Talc was applied on the outer circumference of the cable core.
Next, the sheath compounds A and B were dry-blended at room temperature at the blending ratios shown in the table, and the dry blend was introduced into an extruder having a diameter of 90 mm set at a cylinder temperature of 130 ° C. and a head temperature of 150 ° C. The outer circumference of the cable core was covered with an outer diameter of 11.2 mm and left at room temperature for 4 days. In this way, a sheath was formed by the silane cross-linking method to obtain a cabtire cable.

Comparative Example 10
As described below, a cabtire cable of Comparative Example 10 was manufactured on the outer periphery of the insulated electric wire of the present invention, which was formed of a crosslinked product of a resin composition other than the silane crosslinkable composition J specified in the present invention. ..
-Manufacturing of insulated wires-
The polyolefin resin shown in Table 1 is extruded and coated on the outer circumference of a 37 / 0.26 conductor (outer diameter 1.8 mm) with an extruder of L / D 23 mm and a diameter of 25 mm to an outer diameter of 2.1 mm, and an inner insulating layer is attached. Formed a conductor.
Insulation compounds A and B are dry-blended at room temperature at the blending ratios shown in Table 1, and the dry blend is introduced into an extruder having a diameter of 65 mm set at a cylinder temperature of 165 ° C and a head temperature of 190 ° C to insulate the inside. The outer circumference of the layered conductor was extruded and coated so as to have an outer diameter of 3.5 mm. The obtained coated conductor was left at room temperature for 4 days. In this way, an insulating layer was formed by the silane crosslinking method to obtain an insulated wire.
-Cable manufacturing-
A cable core was made by twisting three of the prepared insulated wires.
Next, the sheath compound C was introduced into a chemical cross-linking extruder having a diameter of 90 mm and the cylinder temperature was set to 80 ° C. By passing it continuously, a sheath was formed by a chemical cross-linking method, and a cabtire cable was obtained.

The following tests were performed on the obtained cabtire cable.

1) Bending durability test FIG. 4 is a schematic view of the equipment used in this test as viewed from the axial direction of the mandrel.
As shown in FIG. 4, the cabtire cable 102 is passed vertically between the two mandrels 51 and 52 arranged horizontally and parallel to each other and between the pressers 61 and 62 for preventing shaking, and the cabtire cable 102 A weight 7 was attached to the bottom. In this state, the upper end of the cabtire cable 102 was bent so as to alternately touch the upper outer periphery of the left and right mandrel 51 or 52 (repeatedly repeating left and right). The number of bends was counted as one when the cabtire cable 102 was bent so as to be in contact with the outer periphery of either the left or right mandrel 51 or 52. The test conditions were a mandrel diameter of 20 mm, a left-right bending angle of 90 °, a speed of 60 bends / minute, a weight of 500 g, a clearance of 1 mm between the cabtire cable and the mandrel, and the upper side surface of the cabtire cable 102. The bending length was adjusted so as to be in contact with the upper outer circumference of the mandrel, and the test was conducted in an atmosphere of 25 ° C. The insulated wires of the cabtire cable were connected in series in a loop and energized, and the number of bends until the conductor of one of the insulated wires was broken was measured. The results are shown in Table 1.
In this test, if the number of bendings until disconnection occurs is 15,000 or more, it is rated as "A", if it is 10,000 or more and less than 15,000, it is rated as "B", and if it is 7,000 or more and less than 10,000, it is rated as "C". Less than 7,000 times was set as D. The determination of the number of bends is passed when it is C or more, but it is preferably B or more, and further preferably A or more.

2) Sheath peeling test The obtained cabtire cable was peeled 50 mm from the end using a wire stripper with a hole diameter of 8.0 mm.
In this test, the one that could be peeled off with a wire stripper (the one that could completely peel off the sheath part to expose the cable core) was passed, and the sheath part could not be peeled off or the entire circumference of the cable with a wire stripper. Those that remained uncut when cutting in the direction were rejected.

3) Insulation layer peeling test 1
The peelability of the insulating layer (inner insulating layer and outer insulating layer) was confirmed by this test.
The sheath was removed from the obtained cabtire cable to expose the cable core. The three insulated wires of the cable core were untwisted, and the insulating layer of one insulated wire was stripped off using a wire stripper having a hole diameter of 1.9 mm and observed.
Those with a whiskers length of 2.5 mm or less on the cut surface passed, those with a whiskers length exceeding 2.5 mm or those that could not be peeled off (inner insulating layer, or inner insulating layer and outer insulating layer are conductors. The one that remained above) was rejected.

In addition to the above, the following characteristics were evaluated. Passing is not always required for these exams.

4) Insulation layer peeling test 2
The peelability of the insulating layer (inner insulating layer and outer insulating layer) was confirmed by this test.
The sheath was removed from the obtained cabtire cable to expose the cable core. The three insulated wires of the cable core were untwisted, and the insulating layer of one insulated wire was stripped off using a wire stripper having a hole diameter of 2.0 mm and observed.
Those with a whiskers length of 2.5 mm or less on the cut surface passed, those with a whiskers length exceeding 2.5 mm or those that could not be peeled off (inner insulating layer, or inner insulating layer and outer insulating layer are conductors. The one that remained above) was rejected. This test is a more severe test assuming that the coating is removed without inserting the blade too deep into the insulating layer so as not to damage the conductor when peeling.

5) Peeling test of the insulating layer after heating 1
The obtained cabtire cable was left at 80 ° C. for 168 hours, after which the sheath was removed to expose the cable core. The three insulated wires of the cable core were untwisted, and the insulating layer of one insulated wire was stripped off using a wire stripper having a hole diameter of 2.0 mm and observed.
In this test, those with a whiskers length of 2.5 mm or less on the cut surface were accepted, and those with a whiskers length exceeding 2.5 mm or those that were not peeled off were rejected. This test is based on the assumption that cabtire cables will be transported or stored in a warehouse. The conductor and inner insulating layer will be exposed to high temperatures during transportation at sea or during storage in the summer. This is an accelerated rigorous test for evaluating whether or not excellent peeling property is maintained even after heating, considering that the adhesion to the skin becomes excessive and the peeling property is lowered.

6) Peeling test of the insulating layer after heating 2
The obtained cabtire cable was left at 80 ° C. for 168 hours, after which the sheath was removed to expose the cable core. The three insulated wires of the cable core were untwisted, and the insulating layer of one insulated wire was stripped off using a wire stripper having a hole diameter of 2.4 mm and observed.
Those with a whiskers length of 4 mm or less on the cut surface were accepted, and those with a whiskers length exceeding 4 mm or those that were not peeled off were rejected. Similar to the peeling test 1 of the insulating layer after heating, this test is a test assuming that the cabtire cable is transported by sea or stored in a warehouse in the summer, but when peeling. This is a more advanced accelerated rigor test assuming the case where the coating is removed without inserting the blade too deep into the insulating layer.

The cabtire cables of Comparative Examples 1 and 2 using an insulated wire in which paper or polyethylene terephthalate tape covered the outer periphery of the conductor failed the peeling property test 1 of the insulating layer.
Comparative Examples 3, 4 and 3. The cabtire cables of and 6 were both inferior in the peelability of the sheath.
The cabtire cable of Comparative Example 5 using an insulated wire in which one layer of an insulating layer containing a cured product obtained by chemical cross-linking of ethylene rubber covers the outer periphery of the conductor was subjected to bending durability and peeling property test 1 of the insulating layer. It was a failure.
The cabtire cable of Comparative Example 7 using a distant electric wire in which one insulating layer containing a cured product by chemical cross-linking of ethylene rubber covers the outer periphery of the conductor and having a sheath by chemical cross-linking has bending durability. The peelability of the sheath and the peelability of the insulating layer were inferior.
The cabtire cables of Comparative Examples 8 and 9 using a remote electric wire having an outer insulating layer by chemical cross-linking, which did not contain ethylene rubber or a styrene-based elastomer, were inferior in bending durability.
The cabtire cable of Comparative Example 10 having a sheath by chemical cross-linking was inferior in bending durability and peeling property of the sheath.
On the other hand, a specific silane crosslinkable composition is used by using a distant electric wire having an inner insulating layer containing the polyolefin resin of the present invention and an outer insulating layer containing a cured product of ethylene rubber and / or a styrene-based elastomer. The cabtyre cables of Examples 1 to 13 having a sheath made of J's silanol condensed and cured product were excellent in bending durability, peelability of the insulating layer, and peeling property of the sheath. Therefore, it can be seen that the peeling work at the time of electrical connection is easy, and it is difficult to break the wire even if it is bent many times. Further, since Examples 1 to 5 and 8 to 13 have passed the peeling test 2 of the insulating layer, they are superior to the peeling test 1 of the insulating layer even in a situation where whiskers are more likely to occur. It can be seen that it shows peeling property. Further, since Examples 1 to 6 and 8 to 13 have passed the peeling tests 1 and 2 of the insulating layer after heating, the peeling property of the insulating layer is less likely to deteriorate even by transportation or storage. You can see that.
Further, Examples 1 to 13 and Comparative Example 10 using an insulated wire having an inner insulating layer containing the polyolefin resin of the present invention and an outer insulating layer containing a cured product of ethylene rubber and / or a styrene-based elastomer are used. In each case, the insulating wire was excellent in peeling property.

101, 102 Cabtyre cable 1,11,12 Conductor 2,21,22 Inner insulation layer 3,31,32 Outer insulation layer 41,42 Sheath 51,52 Mandrel 61,62 Holder for anti-sway 7 Weight 10 Cabtyre cable Insulated wire for

Claims (23)

A cabtire cable in which the outer circumference of an insulated wire is covered with a sheath.
The insulated wire has a conductor, an inner insulating layer that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer.
The inner insulating layer contains a polyolefin resin, and the inner insulating layer contains a polyolefin resin.
The outer insulating layer comprises at least one cured product of ethylene rubber and a styrene-based elastomer.
A cabtire cable in which the sheath is made of a silanol condensed cured product of the following silane crosslinkable composition J.
[Silane Crosslinkable Composition J]
1 to 200 parts by mass of the inorganic filler (Q) and 2 parts by mass of the silane coupling agent (F) grafted with the base resin (B) with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. Silane crosslinkable composition J containing 15.0 parts by mass or less and a silanol condensation catalyst (Y). Claim 1 in which the polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof. The cab tire cable described in. The cabtire cable according to claim 1 or 2, wherein the outer insulating layer is made of a silanol condensed cured product of the following silane crosslinkable composition I.
[Silane Crosslinkable Composition I]
Silane coupling in which 1 to 400 parts by mass of the inorganic filler (P) and the base resin (A) are grafted with respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer. Silane crosslinkable composition I containing 1 to 15.0 parts by mass of the agent (E) and a silanol condensation catalyst (X). The cabtire cable according to any one of claims 1 to 3, wherein the base resin (B) contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer. An insulated wire for a cabtire cable having a conductor, an inner insulating layer covering the outer periphery of the conductor, and an outer insulating layer covering the outer periphery of the inner insulating layer.
The cabtire cable has a sheath made of a silanol condensed cured product of the following silane crosslinkable composition J.
An insulated wire for a cabtire cable, wherein the inner insulating layer contains a polyolefin resin, and the outer insulating layer contains a cured product of at least one of ethylene rubber and a styrene-based elastomer.
[Silane Crosslinkable Composition J]
1 to 200 parts by mass of the inorganic filler (Q) and 2 parts by mass of the silane coupling agent (F) grafted with the base resin (B) with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. Silane crosslinkable composition J containing 15.0 parts by mass or less and a silanol condensation catalyst (Y). 5. Claim 5 that the polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof. Insulated wire for cab tire cables as described in. The insulated wire for a cabtire cable according to claim 5 or 6, wherein the outer insulating layer is made of a silanol condensed cured product of the following silane crosslinkable composition I.
[Silane Crosslinkable Composition I]
Silane coupling in which 1 to 400 parts by mass of the inorganic filler (P) and the base resin (A) are grafted with respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer. Silane crosslinkable composition I containing 1 to 15.0 parts by mass of the agent (E) and a silanol condensation catalyst (X). The insulated wire for a cabtire cable according to any one of claims 5 to 7, wherein the base resin (B) contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer. It has a conductor, an inner insulating layer containing a polyolefin resin that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer and contains a cured product of at least one of ethylene rubber and a styrene-based elastomer. It is a method of manufacturing a cabtire cable in which the outer circumference of an insulated wire is covered with a sheath.
A method for manufacturing a cabtire cable, wherein the inner insulating layer, the outer insulating layer, and the sheath are formed by the following steps (1), (2), and steps (k) to (n), respectively.
Step (1): The outer periphery of the conductor is coated with a polyolefin resin to form the inner insulating layer. Step (2): The outer periphery of the inner insulating layer is coated with at least one of ethylene rubber and a styrene-based elastomer. Step of curing at least one of the ethylene rubber and the styrene-based elastomer to form the outer insulating layer Step (k): Organic peroxide with respect to 100 parts by mass of the base resin (B) containing the halogen-containing resin. (D) A silane coupling agent (F) having 0.003 to 0.3 parts by mass of an inorganic filler (Q), 1 to 200 parts by mass of an inorganic filler (Q), and a grafting reaction site capable of crosslinking with the base resin (B). ) A silane master batch containing a silane crosslinkable resin H by melt-mixing more than 2 parts by mass and 15.0 parts by mass or less to carry out a grafting reaction between the grafting reaction site and the base resin (B). Step of preparing L Step (l): A step of melt-mixing the silane master batch L and the silanol condensation catalyst (Y) to obtain a silane crosslinkable composition J Step (m): In the silane crosslinkable composition J Step (n): Step of contacting the sheath precursor with moisture to form the sheath by covering the outer periphery of the insulated wire. 9. The polyolefin resin contains polyethylene, an ethylene-α-olefin copolymer, a polyolefin copolymer having an acid copolymer component or an acid ester copolymer component, and polypropylene, or a combination thereof. The method for manufacturing a cab tire cable described in. The method for manufacturing a cabtire cable according to claim 9 or 10 , wherein the inner insulating layer is not heated to a temperature exceeding the melting point + 60 ° C. of the polyolefin resin after the coating in the step (2). The method for manufacturing a cabtire cable according to any one of claims 9 to 11 , wherein the step (2) is performed by the following steps (a) to (d).
Step (a): With respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer, 0.01 to 0.6 parts by mass of the organic peroxide (C) and an inorganic filler ( P) 1 to 400 parts by mass and 1 to 15.0 parts by mass of a silane coupling agent (E) having a grafting reaction site capable of crosslinking with the base resin (A) are melt-mixed and the graft is formed. Step of preparing a silane master batch K containing a silane crosslinkable resin G by grafting a chemical reaction site with the base resin (A) Step (b): The silane master batch K and a silanol condensation catalyst (X). ) Is melt-mixed to obtain a silane crosslinkable composition I. Step (c): A step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition I to form an outer insulating layer precursor (d). ): A step of contacting the outer insulating layer precursor with water to form the outer insulating layer. The production of the cabtire cable according to claim 12 , wherein a part of the base resin (A) is melt-mixed in the step (a), and the rest of the base resin (A) is melt-mixed in the step (b). Method. The method for manufacturing a cabtire cable according to any one of claims 9 to 13 , wherein the base resin (B) contains chlorinated polyethylene, polyvinyl chloride, and a plasticizer. The invention according to any one of claims 9 to 14 , wherein a part of the base resin (B) is melt-mixed in the step (k) and the rest of the base resin (B) is melt-mixed in the step (l). The method of manufacturing the cabtire cable described. The method for manufacturing a cabtire cable according to any one of claims 9 to 15 , wherein the balance of the base resin (B) contains chloroprene rubber. The method for manufacturing a cabtire cable according to any one of claims 9 to 16 , wherein the inorganic filler (Q) contains 2 parts by mass or more of silica. The method for manufacturing a cabtire cable according to any one of claims 9 to 17 , wherein the mixing amount of the inorganic filler (Q) in the step (k) is 3 to 60 parts by mass. The method for manufacturing a cabtire cable according to any one of claims 9 to 18 , wherein the melt mixing in the step (k) is performed with a closed mixer. It has a conductor, an inner insulating layer containing a polyolefin resin that covers the outer periphery of the conductor, and an outer insulating layer that covers the outer periphery of the inner insulating layer and contains a cured product of at least one of ethylene rubber and a styrene-based elastomer. The method for manufacturing an insulated wire for a cabtire cable, which is used in the steps (k) to (n) of the method for manufacturing a cabtire cable according to any one of claims 9 to 19 .
A method for manufacturing an insulated wire for a cabtire cable, wherein the inner insulating layer and the outer insulating layer are formed by the following steps (1) and (2), respectively.
Step (1): The outer periphery of the conductor is coated with a polyolefin resin to form the inner insulating layer. Step (2): The outer periphery of the inner insulating layer is coated with at least one of ethylene rubber and a styrene-based elastomer. A step of curing at least one of the ethylene rubber and the styrene-based elastomer to form the outer insulating layer. The method for manufacturing an insulated wire for a cabtire cable according to claim 20 , wherein the inner insulating layer is not heated to a temperature exceeding the melting point of the polyolefin resin + 60 ° C. after the coating in the step (2). The method for manufacturing an insulated wire for a cabtire cable according to claim 20 or 21 , wherein the step (2) is performed by the following steps (a) to (d).
Step (a): With respect to 100 parts by mass of the base resin (A) containing at least one of ethylene rubber and a styrene-based elastomer, 0.01 to 0.6 parts by mass of the organic peroxide (C) and an inorganic filler ( P) 1 to 400 parts by mass and 1 to 15.0 parts by mass of a silane coupling agent (E) having a grafting reaction site capable of crosslinking with the base resin (A) are melt-mixed and the graft is formed. Step of preparing a silane master batch K containing a silane crosslinkable resin G by grafting a chemical reaction site with the base resin (A) Step (b): The silane master batch K and a silanol condensation catalyst (X). ) Is melt-mixed to obtain a silane crosslinkable composition I. Step (c): A step of covering the outer periphery of the inner insulating layer with the silane crosslinkable composition I to form an outer insulating layer precursor (d). ): A step of contacting the outer insulating layer precursor with water to form the outer insulating layer. 22. The insulation for a cabtire cable according to claim 22, wherein a part of the base resin (A) is melt-mixed in the step (a), and the rest of the base resin (A) is melt-mixed in the step (b). How to manufacture electric wires.

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