JP5534544B2 - Insulated wires and multilayer wires - Google Patents

Description

  The present invention relates to an insulated wire used in an electronic device or an automobile, a manufacturing method thereof, and a multilayered wire in which the insulated wire is covered with a jacket.

  Insulated wires used in electronic devices and automobiles are generally formed by covering the outer periphery of a central conductor with an insulating layer made of resin or the like. Such insulated wires are often shipped in the form of being wound on a reel. However, while the wires are in contact with each other and stored in the reel, the wires may be stuck or blocked. is there. The sticking or blocking of the electric wires may lead to marking peeling of the insulating layer or tearing of the insulating layer, which causes a complaint.

  Therefore, a method for preventing the wires from sticking and blocking is considered. For example, a method of adding an antiblocking agent or a lubricant to the resin constituting the insulating layer is known.

  For such an insulated wire, adhesion and fusion when used in a high temperature atmosphere may be a problem. For example, if the bound insulated wires are left in a high-temperature atmosphere, the wires may adhere to each other, peeling of the coating occurs when the binding is released (insulation layer peeling), and in serious cases, the conductor is exposed. In particular, when heated near the melting point of the insulating layer or above the melting point, the wires are fused, and this problem is remarkable.

  In order to prevent such adhesion and fusion between electric wires, a method of crosslinking the resin by irradiating the insulating coating with ionizing radiation is effective. In this case, oxygen in the air becomes a factor for inhibiting cross-linking. Therefore, a method for removing the release layer after coating a peelable resin on the insulated wire coating layer and irradiating with ionizing radiation has been proposed. (Patent Document 1). According to this method, the cross-linking efficiency of the insulating coating can be improved even by irradiation with ionizing radiation in the air, and adhesion of electric wires in a high-temperature atmosphere can be prevented. Further, there is no need to perform ionizing radiation irradiation in an inert gas atmosphere, and no significant facility modification is required.

  The insulated wire may be used as a multilayered wire (insulated wire having a multilayer coating layer of two or more layers) further provided with a shield layer or other jacket on the outermost periphery. In many cases, such multi-layer electric wires are used only when the outer sheath is removed and the inner insulated wires are used, but when the outer sheath and the inner insulated wires are fixed or fused, the outer sheath is removed. It becomes an obstacle.

Therefore, as a method of preventing adhesion and fusion between the outer sheath and the inner insulated wire, a method of applying silicone oil to the surface of the inner insulated wire (Patent Document 2) or talc powder before the outer sheath is formed. A method of attaching is known.
JP 2006-19147 A JP 2003-7143 A

  However, any of the above-described methods has the following problems, and a solution is desired.

  There is no anti-blocking agent that can be applied to all types of resin, and there is no anti-blocking agent that can be applied to all types of resin by adding an anti-blocking agent or lubricant to the resin that constitutes the insulation coating layer. It is necessary to use properly. In addition, there is a problem that the appearance of the insulated wire is poor, such as an anti-blocking agent bleed out and aggregates are deposited on the surface of the insulated wire, which may cause various complaints.

  Further, in order to suppress the adhesion of the electric wire when used in a high temperature atmosphere, a method in which a resin that can be peeled is further coated on the covering layer of the insulated electric wire and this layer is peeled after the electron beam irradiation ( The method described in Patent Document 1 is not easily performed because it requires extruding and removing the peelable resin layer, and the material loss is large.

  Furthermore, in order to prevent obstacles in the operation of removing the outer sheath of the multilayer electric wire, a certain amount of the method of applying silicone oil to the surface of the insulated wire (the method described in Patent Document 2) and the method of attaching talc powder However, it is difficult to stably reduce the force necessary for removing the outer cover. Further, when silicone oil is used, surface contamination due to bleed-out and short circuit due to generation of cyclic silicone are problematic.

  The present invention provides an insulated wire that prevents the occurrence of sticking and blocking between wires during storage, suppresses adhesion between wires in a high-temperature atmosphere, and does not easily cause bleed-out or poor appearance during long-term storage. The issue is to provide. Another object of the present invention is to provide a method by which this insulated wire can be easily manufactured.

  Moreover, this invention makes it a subject to provide the insulated wire by which the adhesion | attachment of the wires in a high temperature atmosphere is suppressed more effectively as the further preferable aspect of the said invention.

  It is another object of the present invention to provide a multilayer electric wire that is stable and easy to remove and has no problems such as bleed out and poor appearance.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventor has found that the insulating wires can be prevented from sticking by uniformly coating the surface of the insulating layer with a water-swellable layered silicate.

The invention according to claim 1 has been completed based on such knowledge, and is a conductor, an insulating layer covering the outer periphery thereof, and a coating of a water-swellable layered silicate formed on the surface of the insulating layer. have a layer, the water-swellable layered silicate, smectite clays, vermiculite based clays, halloysite, swelling mica, and selected mixtures thereof, wherein the insulating layer is a resin crosslinked by irradiation with ionizing radiation Thus, the thickness of the coating layer is 0.03 μm to 10 μm, and provides an insulated wire.

  In this insulated wire, a water-swellable layered silicate coating layer is formed on the surface of the insulating layer, that is, on the outer periphery of the insulated wire, so that the water-swellable layered silicate is between the insulated wires in contact with each other. This prevents the direct contact between the insulating layers and prevents the insulated wires from sticking to each other. As long as the thickness of the water-swellable layered silicate coating layer is not too large, the appearance of the electric wire is not impaired, so there is no problem of appearance failure, and there is no bleeding out problem during long-term storage.

  Also, the melting point of the water-swellable layered silicate is much higher than the temperature when using an insulated wire. In the case of the prior art as described above, even in a high temperature atmosphere where the wires are easily bonded to each other, the bonding between the wires is suppressed by interposing the high-melting-point water-swellable layered silicate between the insulating layers. .

  FIG. 1 is a diagram schematically showing a cross-sectional structure of an example of an insulated wire according to claim 1. As is apparent from FIG. 1, the insulated wire has a conductor 1 (conductor wire) disposed in the center, and the outer periphery of the conductor 1 is covered with an insulating layer 2 made of an insulating material (resin). The outer periphery of 2 is covered with a water-swellable layered silicate 3. In the example of FIG. 1, the insulating layer 2 is one layer, but the case where the insulating layer is composed of two or more layers is also included in the insulated wire of the present invention.

The water-swellable layered silicate is a layered silicate that easily swells with water, and in some cases, the layer is separated and dispersed in water, and generally constitutes clay or clay. Known as a representative mineral. Its main components are silicon, magnesium and aluminum, and may contain a small amount of alkali metals such as sodium, potassium and lithium, alkaline earth metals and other metals. For example, the formula _{(Al 4-y Mg y)} (Si 8) O 20 (OH) ( wherein, X is a metal such as an alkali metal or alkaline earth metal.) 4 _{X z} those represented by Can be mentioned.

Examples of the water-swellable layered silicate include smectite clay, vermiculite clay, halloysite, and swellable mica. One of these may be used alone, or two or more selected from these may be mixed. Use .

  Here, as the smectite clay, natural or synthetic smectites such as montmorillonite (bentonite), beidellite, hectorite, saponite, stevensite, soconite, nontronite and the like can be mentioned. Synthetic smectite can be produced, for example, by the method described in Japanese Examined Patent Publication No. 61-12848 or a similar method.

  As swelling mica, Li-type fluorine teniolite, Na-type fluorine teniolite, Na-type tetrasilicon fluorine mica, Li-type tetrasilicon fluorine mica, etc., which are naturally or chemically synthesized and have Li ions or Na ions between the layers Mention may be made of sexual mica or a mixture thereof. Vermiculite, fluorine vermiculite, and the like can also be used.

  A commercial item can be used for these water-swellable layered silicates. Commercially available products include Laponite XLG (synthetic hectorite analogue manufactured by LaPorte), Laponite RD (synthetic hectorite analogue produced by LaPorte), Thermabis (synthetic hectorite analogue manufactured by Henkel), Smecton SA-1 (Similar saponite manufactured by Kunimine Kogyo Co., Ltd.), Wenger (natural montmorillonite sold by Toyoshun Yoko Co., Ltd.), Kunipia F (natural montmorillonite sold by Kunimine Kogyo Co., Ltd.), Veagam (natural hectorite manufactured by Vanderbilt), Dimonite (Topy Synthetic swelling mica manufactured by Kogyo Co., Ltd.), Somasifu (ME-100, synthetic swelling mica manufactured by Corp Chemical), SWN (synthetic smectite manufactured by Corp Chemical), SWF (synthetic smectite manufactured by Corp Chemical), etc. Can be mentioned.

  These water-swellable layered silicates are easily swollen by water, and in some cases, the layers are peeled and dispersed, so that the aqueous dispersion can be easily produced, and the aqueous dispersion is insulated. By coating on the surface of the electric wire and drying, it is possible to uniformly coat the electric wire and form a coating layer.

  The thickness of the water-swellable layered silicate coating layer may be about 0.03 μm to 10 μm. Even with such a thickness, the above-mentioned effect is sufficiently achieved. In addition, in the case where the crosslinking by irradiation with ionizing radiation described later is performed after the coating of the water-swellable layered silicate, if the water-swellable layered silicate coating layer is thick, the coating layer may inhibit the crosslinking. If the thickness is within the above range, it does not cause the inhibition of crosslinking.

  By providing a water-swellable layered silicate coating layer, the adhesion between wires due to use in a high-temperature atmosphere is also suppressed, but when the atmosphere becomes a temperature close to the melting point of the insulating layer or a temperature higher than the melting point, In some cases, this means alone cannot sufficiently prevent adhesion in a high temperature atmosphere. Furthermore, when the temperature is higher than the melting point, it is difficult to maintain the shape of the insulating layer itself. In particular, this problem is likely to occur when the melting point of the resin constituting the insulating layer is low.

  In such a case, if the resin constituting the insulating layer is cross-linked by irradiation with ionizing radiation, the adhesion (fusion) between the wires due to use in a high-temperature atmosphere is more effectively suppressed, and the shape of the insulating layer is also maintained. It is preferable because it is possible. That is, the insulated wire of the present invention, which is made of a resin in which the insulating layer is irradiated with ionizing radiation and cross-linked, can more effectively suppress adhesion between wires that is likely to occur in a high-temperature atmosphere.

  Examples of ionizing radiation used for cross-linking include high-energy electromagnetic waves such as gamma rays and X-rays, electron beams, etc., but the curing speed is high (productivity is high), and control and management are easy. And an electron beam is preferred. The electron beam irradiation can be performed using the same apparatus and method as in the case of the known electron beam irradiation performed for resin crosslinking. When the irradiation dose used for crosslinking is too small, crosslinking may be insufficient and the effect of crosslinking may not be sufficiently obtained. On the other hand, when the irradiation dose used for crosslinking is too large, the elongation of the coating is lost and discoloration may occur. Therefore, an optimal dose is selected in consideration of these points.

  The insulated wire of the present invention is formed by coating the conductor with a resin constituting the insulating layer by a known method to form a covered wire (a coated wire having an insulating layer made of a resin covering the conductor and its outer periphery) It can be produced by a method of coating the surface of the insulating layer with a water-swellable layered silicate.

  The process of coating the surface of the covered electric wire (that is, the surface of the insulating layer) with the water-swellable layered silicate is performed by passing the covered electric wire through an aqueous dispersion of the water-swellable layered silicate and attaching the aqueous dispersion to the surface of the electric wire. Then, the aqueous dispersion can be dried. As described above, the water-swellable layered silicate is easily dissolved in water or dispersed / peeled in water, so that a uniform layer (thin film) of the water-swellable layered silicate can be easily formed on the insulating layer surface by this method. Can be formed. Therefore, the insulated wire of the present invention can be easily manufactured by this manufacturing method.

The concentration of the water-swellable layered silicate aqueous dispersion is preferably 10% by mass or less.

When the concentration of the aqueous dispersion exceeds 10% by mass , there may be problems such as poor application uniformity and poor appearance of the electric wire after drying. When the concentration is 10% by mass or less, uniform coating is possible, and the coating is transparent after drying and does not deteriorate the appearance of the electric wire. Moreover, if it is 10 mass % or less, preparation of an aqueous dispersion is also easy. More preferably, the concentration is in the range of 0.1 to 10% by mass . When the concentration is less than 0.1% by mass , it may be difficult to obtain a layer (thin film) having a predetermined thickness.

  As a method of passing the covered electric wire through an aqueous dispersion of a water-swellable layered silicate and drying the aqueous dispersion adhering to the surface of the insulating layer, an aqueous dispersion of the water-swellable layered silicate is used in the wire pass line. Give a method of installing a filled water tank, passing the covered electric wire through the water tank, and drying the aqueous dispersion adhering to the surface of the covered electric wire by natural drying or hot air drying before reel winding. Can do.

An insulated wire made of a resin crosslinked with an insulating layer irradiated with ionizing radiation can be produced by a method in which the insulating layer is irradiated with ionizing radiation to crosslink the resin constituting the insulating layer. The significance, method, and conditions of ionizing radiation irradiation are the same as described above .

Either the water-swellable layered silicate coating or the irradiation with ionizing radiation may be performed first. That is, after forming an insulating layer made of an insulating material on the conductor and coating the surface of the insulating layer with a water-swellable layered silicate, the conductor may be irradiated with ionizing radiation,
After forming an insulating layer made of an insulating material on the conductor and irradiating the insulating layer with ionizing radiation, a water-swellable layered silicate may be coated. In any case, the effects of the present invention are achieved.

  When irradiation with ionizing radiation is performed after coating, since the insulating layer is shielded from air, inhibition of crosslinking by oxygen can be prevented. Therefore, it is not necessary to provide facilities for irradiation under an inert gas atmosphere such as nitrogen, and a coating layer that is peeled off and discarded before commercialization as in the technique described in Patent Document 1 is further formed. In addition, there is no need for complicated processes such as peeling and disposal, and the insulated wire of the present invention can be easily and inexpensively manufactured.

  In addition, even after irradiation with ionizing radiation such as electron beam after coating, the water-swellable layered silicate coating may peel off or drop off due to the high affinity between the resin constituting the insulating layer and the water-swellable layered silicate. Never do.

The invention of claim 2 is a multilayer wire, characterized in that it comprises insulated wire according to claim 1, and the envelope covering the outer periphery of the insulated wire.

A multilayer electric wire is an electric wire, a cable, or the like in which a sheath covering an insulating layer is provided on the outer periphery of an insulated wire having a conductor and an insulating layer covering the outer periphery thereof. FIG. 2 is a diagram schematically showing a cross-sectional structure of an example of the multilayer electric wire according to claim 2 . 2, 1, 2, and 3 are a conductor, an insulating layer, and a water-swellable layered silicate, respectively, and this portion is the same as the insulated wire in FIG. 1.

  Two or more insulated wires may be included in the multilayer wire. That is, an electric wire, a cable, or the like in which the outer periphery of a twisted wire obtained by twisting two or more parallel insulated wires or two or more insulated wires with a jacket is also a multilayer electric wire.

  2 in FIG. 2 is a jacket. Examples of the material for the jacket include those generally used as an insulating material. For example, the same resin as described later as the resin constituting the insulating layer covering the conductor can be exemplified as the material of the jacket. The jacket may be composed of two or more layers. When the outer cover has two or more layers, the inner layer of the outer cover may be called an interposition.

  In such a multilayer electric wire, the outer sheath may be removed and only the internal insulated wire may be used for use. However, the outer sheath or the insulated electric wire is removed by pulling one from the other. Is called. In this case, when the insulating layer of the insulated wire and the outer cover are fixed and fused, it is difficult to remove the outer cover, and the workability (customer workability) at the time of use decreases. As is clear from FIG. 2, the multilayer electric wire of the present invention has a water-swellable layered silicate layer (3 in the figure) between the insulating layer 2 and the jacket 4, so that the insulating layer and the outer The occurrence of adhesion and fusion between the coverings is prevented, the force required to remove the covering (the covering removing force) is reduced, and the customer processability is improved. In addition, since the water-swellable layered silicate can be uniformly and stably coated as described above, the decrease in the coat removal force is stable, which has been a problem when using conventional talc and silicone. Variations in the jacket removal force are unlikely to occur. That is, the multilayer electric wire of the present invention has an excellent feature that the outer wire removal of the insulated wire is stable and easy. Furthermore, since the multilayered electric wire of the present invention uses the insulated electric wire of the present invention, the insulated electric wire from which the outer sheath has been removed does not have a problem such as an appearance defect due to bleed-out.

  In the example of FIG. 2, the insulating layer 2 and the jacket 4 are each one layer, but both the insulating layer and the jacket may include two or more layers made of different types of materials. In this case, the water-swellable layered silicate layer is provided between the outermost layer of the insulating layer and the innermost layer of the jacket.

  In the example of FIG. 2, the cross-sectional shape is a perfect circle, but the multi-layer electric wire of the present invention may have an elliptical shape, a flat angle, or other irregular shapes. Even if it is not a perfect circle, by providing a water-swellable layered silicate layer between the insulating layer and the jacket, adhesion and fusion between the insulating layer and the jacket can be prevented, and the force required to remove the jacket (Coating removal force) is stably reduced, and customer processability is improved.

  The multilayer electric wire of the present invention is produced by the above-mentioned method by producing an insulated wire having a conductor and an insulating layer covering the outer periphery thereof, the surface of the insulating layer being coated with a water-swellable layered silicate, and the insulation. It can be easily manufactured by a method of covering the outer periphery of the electric wire by a known method.

  The insulated wire of the present invention occurs when the wires are used in contact with each other in a reel or the like, which may occur when the wires are fixed, blocked, or bundled together in a high temperature atmosphere. Adhesion between easy electric wires is suppressed, and bleeding out and poor appearance during long-term storage are less likely to occur. These insulated wires can be easily manufactured by the method of the present invention.

  Next, a mode for carrying out the present invention, particularly the best mode will be described. However, the scope of the present invention is not limited to only this mode, and various modifications can be made without departing from the spirit of the present invention. It is possible to add.

  The material and form of the conductor constituting the insulated wire of the present invention are not particularly limited. It may be a single wire or a stranded wire. The cross-sectional shape may be a perfect circle or another shape. The thickness is not limited. Any material may be used as long as it is used for ordinary electric wires.

  The kind of the resin constituting the insulating layer covering the conductor is not particularly limited as long as it has insulating properties and can be extruded to cover the conductor. For example, polyethylene, polypropylene, ethylene binary and ternary copolymers, graft polymers of these polymers, thermoplastic elastomers, plant-derived resins, biodegradable resins, engineering plastics also have insulating layers. It can be used as a constituent resin. What blended two or more types of resin can also be used. As long as extrusion for forming the coating layer is possible, a flame retardant, a colorant, a crosslinking aid, an antioxidant, a metal deactivator, and the like may be added to the resin as necessary.

  Next, the manufacturing apparatus 11 for manufacturing suitably the insulated wire 10 of this invention is demonstrated based on FIG. As shown in FIG. 3, the manufacturing apparatus 11 includes a coating apparatus 12, a cooling water tank 13, an anti-adhesive agent aqueous dispersion tank 14 (a water tank filled with an anti-adhesion / fusing inhibitor aqueous dispersion), a dryer zone 15, and An electron beam irradiation device 16 is provided.

  The coating device 12 is provided with an extruder zone 23. The conductor 1 is wound around and stored in the unwinding portion 21, but is fed out from the unwinding portion 21 in the direction of the arrow in the drawing and passes through the extruder zone 23. By the extruder provided in the extruder zone 23, the resin constituting the insulating layer 2 is extruded onto the surface of the conductor 1, and the conductor 1 is covered with the resin to form the covered electric wire 5. As the extruder provided in the extruder zone 23, a known extruder such as a single screw extruder can be used.

  The covered electric wire 5 exiting the covering device 12 is cooled by passing through the cooling water tank 13, and the resin of the insulating layer is solidified. After that, the covered electric wire 5 passes through the anti-adhesive agent aqueous dispersion tank 14, so that the anti-adhesion / fusing agent aqueous dispersion adheres to the outer periphery thereof. The time passing through the anti-sticking agent aqueous dispersion tank 14 may be as short as several seconds. Since it is not necessary to make the time passing through the anti-adhesion agent aqueous dispersion tank 14 long, the capacity of the anti-adhesion agent aqueous dispersion tank 14 can be reduced. The capacity of the anti-adhesive agent aqueous dispersion tank 14 is appropriately selected in consideration of the extrusion linear speed and the winding linear speed. Moreover, it is also possible to apply | coat the anti-adhesion agent water dispersion liquid to the covered electric wire 5 by spray injection, and it is also possible to make the part of the said anti-adhesion agent water dispersion tank 14 into a spray application tank.

  The anti-sticking agent aqueous dispersion tank 14 is filled with an aqueous dispersion of a water-swellable layered silicate. The aqueous dispersion of the water-swellable layered silicate can be prepared simply by adding the water-swellable layered silicate to normal water and dispersing it with stirring. In order to further facilitate dispersion of the water-swellable layered silicate in water, ultrasonic waves or the like may be used, or water-soluble resins such as low molecular weight water-soluble materials such as PVA and aqueous urethane, dispersions. May be simultaneously added to water. When these are added, the flexibility of the water-swellable layered silicate coating layer produced on the insulated wire is improved and the adhesion to the insulating layer is improved, which is preferable from the viewpoint of preventing peeling.

  The coated electric wire 5 with the adhesion / fusing inhibitor aqueous dispersion (water swellable layered silicate aqueous dispersion) adhered to the outer periphery thereof is sent to the dryer zone 15 and dried to form the insulated wire 10 of the present invention. Examples of the drying method include a method in which a drying furnace provided in the dryer zone 15 is set to about 50 to 80 ° C. and the electric wire is passed through in about 1 to 3 minutes. A method in which dryer hot air is applied to an electric wire passing through the dryer zone 15 for several tens of seconds may be used. Alternatively, even with a method of natural drying, that is, a method in which the air-cooled section is passed for several tens of seconds, the water-swellable layered silicate coating layer can achieve such adhesion that the insulating layer does not peel off or drop off.

  The insulated wire 10 exiting the dryer zone 15 is sent to the electron beam irradiation device 16 where it is irradiated with the electron beam and the resin constituting the insulating layer is cross-linked. In the example of FIG. 3, the electron beam irradiation device 16 is provided after the dryer zone 15, and the crosslinking is performed after the coating of the water-swellable layered silicate. However, it is also possible to employ a method in which the electron beam irradiation device 16 is provided in front of the anti-adhesion agent aqueous dispersion tank 14 and the water-swellable layered silicate is coated after crosslinking. As the electron beam irradiation apparatus 16, the thing similar to the well-known electron beam irradiation apparatus used for bridge | crosslinking of the coating layer of an electric wire can be used.

  In addition, according to the manufacturing apparatus shown in FIG. 3, each process of coating of an insulating layer, coating of a water-swellable layered silicate, drying, and electron beam irradiation is performed continuously. It is also possible to do this. For example, after the coating of the insulating layer, the coating of the water-swellable layered silicate and the drying step, the electric wire may be temporarily wound, and the wound electric wire may be irradiated later with an electron beam.

  A reel 17 is installed behind the electron beam irradiation device 16, and the manufactured insulated wire is wound around the reel 17.

  Next, examples for more specifically explaining the present invention will be shown, but the examples do not limit the scope of the present invention.

Producing ethylene Production Example 1 insulating layer-forming resin composition - vinyl copolymer 100 parts by weight acetic acid, 100 parts by weight of magnesium hydroxide, an antioxidant (pentaerythritol - tetrakis [3- (3,5-di -t- butyl-4-hydroxyphenyl) propionate] 1 part by weight, crosslinking aid (triethylene glycol dimethacrylate) and 3 parts by mass, a biaxial mixer (30mmφ, L / D = 30 , barrel temperature 140 ° C., a screw rotation speed of 100rpm The resin composition for forming an insulating layer was obtained by using a strand cut pelletizer, and pellets of the resin composition for forming an insulating layer were prepared.

Production Examples 2 to 4 Production of Adhesion / Fixing Prevention Agent Aqueous Dispersion The following fixation / fusing inhibitor was dispersed in water so that the concentrations shown in Table 1 were obtained. Obtained. The dispersibility of the fixing / fusing inhibitor in these aqueous dispersions was visually observed, and the results are shown in Table 1 based on the following criteria.

[Dispersibility criteria for aqueous dispersions]
Good: The powder is not dispersed in water and does not show powder floating on the liquid surface.
Poor (NG): A state in which the agglomerated powder is not dispersed in water but floats on the liquid surface or inside.

[Fixing / Fusing Agent]
Water swellable layered silicate A:
Fine powder type bentonite product (main component montmorillonite, interlayer distance about 1 nm, viscosity of 7 wt% aqueous dispersion is about 2500 cps).
-Layered silicate B:
Talc composed mainly of magnesium silicate (manufactured by Nippon Talc Co., Ltd .: Talc PP).

As shown in Table 1, the dispersibility of the layered silicate B was poor (NG) even at a concentration of 1% by mass . On the other hand, the water-swellable layered silicate A had good dispersibility even at a concentration of 5% by mass .

Reference Example 0.127 mmφ manufactured by using a single screw melt extruder (45 mmφ, L / D = 24) on the outer periphery of a stranded wire (twisted wire diameter 3.8 mmφ) based on 50 unplated copper wires The insulating layer-forming resin composition obtained in Example 1 was extruded to produce a covered electric wire. After the coated electric wire extruded from the single screw melt extruder is cooled through a cooling water tank installed immediately after the extrusion part of the single screw melt extruder, the anti-adhesive agent water dispersion installed at the rearmost part of the cooling water tank The liquid tank, that is, the water tank (length: 50 cm) filled with the fixing / fusing inhibitor aqueous dispersion (1 mass % aqueous dispersion of the water-swellable layered silicate A) prepared in Production Example 2 was passed in 2 seconds. Then, a coated electric wire in which an aqueous dispersion of a water-swellable layered silicate adhered to the outer surface was obtained.

  Thereafter, the insulated wire is passed through the dryer installation zone in 5 seconds, and the attached aqueous dispersion is dried, so that an insulated wire coated with water-swellable layered silicate A (referred to as insulated wire 1) is obtained. This was obtained and wound on a reel. The thickness of the insulation coating was 0.75 mm, and the outer diameter of the insulated wire 1 was 5.3 mm (the same applies to Examples 2 to 4 below).

Example 2
An insulated wire coated with water-swellable layered silicate A was produced under the same conditions as in the reference example . Thereafter, the produced insulated wire was irradiated with an accelerating electron beam having an acceleration voltage of 2000 kv in an air atmosphere and subjected to a crosslinking treatment, and then this insulated wire (referred to as insulated wire 2) was wound on a reel.

Example 3
The resin composition for forming an insulating layer was coated on the outer periphery of the base wire under the same conditions as in the reference example . The prepared coated electric wire was irradiated with an accelerating electron beam having an accelerating voltage of 2000 kv in an air atmosphere to perform a crosslinking treatment. After that, the covered electric wire was passed through the water tank filled with the fixing / fusing inhibitor aqueous dispersion (1% by weight aqueous dispersion of water-swellable layered silicate A) prepared in Production Example 2 for 2 seconds, and further reference Drying was performed under the same conditions as in the example to produce an insulated wire (insulated wire 3) coated with water-swellable layered silicate A, and this was wound on a reel.

Example 4
The resin composition for forming an insulating layer was coated on the outer periphery of the base wire under the same conditions as in the reference example . The prepared coated electric wire was irradiated with an accelerating electron beam having an accelerating voltage of 2000 kv in an air atmosphere to perform a crosslinking treatment. After that, the suction type spray gun SSG which injects the coated wire in 2 seconds with the sticking / fusing inhibitor aqueous dispersion (1% by weight aqueous dispersion of water-swellable layered silicate A) prepared in Production Example 2. It passed through the spray spray tank which installed 2-13 (made by Trusco Nakayama Co., Ltd.). Furthermore, it dried on the same conditions as a reference example , the insulated wire (it was set as the insulated wire 4) coated with the water-swellable layered silicate A was produced, and this was wound up on the reel.

Example 5
Instead of the fixing / fusing inhibitor aqueous dispersion prepared in Production Example 2, the fixing / fusion preventing agent aqueous dispersion prepared in Production Example 3 (5% by mass aqueous dispersion of water-swellable layered silicate A) An insulated wire (referred to as insulated wire 5) was prepared under the same conditions as in Example 3 except that was used, and this was wound on a reel.

Comparative Example 1
An insulated wire (referred to as insulated wire 6) was prepared under the same conditions as in Example 2 except that the step of passing the water tank filled with the water dispersion of the fixing / fusion-preventing agent was not performed, and this was wound on a reel. .

Comparative Example 2
Instead of the fixing / fusing inhibitor aqueous dispersion prepared in Production Example 2, the fixing / fusion preventing agent aqueous dispersion (1% by mass aqueous dispersion of layered silicate B) prepared in Production Example 4 was used. An insulated wire (referred to as insulated wire 7) was produced under the same conditions as in Example 3 except that it was used, and this was wound on a reel.

Comparative Example 3
Insulation under the same conditions as in Production Example 1 except that the resin composition for forming an insulating layer obtained by adding 1 part by mass of oleic acid amide (anti-blocking agent) at the stage of melting and kneading the resin composition was used. A resin composition for layer formation was obtained. Other than using the resin composition for forming an insulating layer in place of the resin composition for forming an insulating layer obtained in Production Example 1 and not using an aqueous dispersion of the fixing / fusing inhibitor. Produced an insulated wire (insulated wire 8) under the same conditions as in the reference example, and wound this around a reel.

[Evaluation of insulated wires]
The following evaluation was performed about each of the insulated wire obtained by the reference example, Examples 2-5 , and Comparative Examples 1-3. The results are shown in Table 2.

(appearance)
The external appearance of the insulated wires 1-8 was confirmed. Compared with the insulated wire (Comparative Example 1) to which the fixing / fusing inhibitor was not applied, the one in which the aggregates could be visually confirmed was defined as NG, and the one in which the visual difference could not be distinguished was defined as good.

(Fixation)
After the insulated wires 1 to 8 wound on the reel were stored in a room at a temperature of 40 ° C. and a humidity of 50% for 1 day, the presence / absence of adhesion between the wires was confirmed. The case where the insulation wire was stuck with the lower insulation wire due to its own weight was defined as NG, and the case where there was no retention was determined as good.

(Fusion)
From each of the insulated wires 1 to 8, three wires having a length of 20 cm were cut out, and the three wires were bound at a position of 1 cm end using a binding band (made of 66 polyamide). After binding, it was left in a constant temperature bath at 150 ° C. for 1 hour. After leaving, it was taken out from the thermostat and cooled, and then the binding band was released and the wires were peeled off to confirm the presence or absence of fusion. When the wire was peeled off, it was assumed that the insulation had been whitened, the one that had been torn or torn was fused, and determined as NG. When the electric wire was peeled off, it could be easily peeled off, and the insulation was not whitened, broken or broken.

(Long-term storage: presence or absence of bleed)
After the insulated wires 1 to 8 were stored for one month, the presence or absence of white powder (bleed) on the surface of the wires was observed.

Reference Examples, Examples 2 to 4 are insulated electric wires coated with a water-swellable layered silicate that easily swells with water as an anti-adhesion and anti-fusing agent, and dried, with agglomerates after drying. No appearance was observed, no sticking after winding was observed, and no bleed-out after long-term storage was observed. By comparison with this result and the result of the comparative example described later, the coating of the water-swellable layered silicate on the outer periphery of the insulated wire can prevent sticking during winding and storage, and the appearance is good, and the bleed out is also possible. It is clear that it does not occur.

  Example 2 was obtained by performing electron beam irradiation after coating the water-swellable layered silicate. Example 3 was obtained by performing water-swellable layered silicate coating after performing the electron beam irradiation. It is. Further, in Example 4, the coating of the water-swellable layered silicate was performed by spray application, not immersion in the anti-adhesion agent aqueous dispersion tank, but all of Examples 2 to 4, Even when stored in a bundled state in a high temperature (150 ° C.) atmosphere, no fusion of the insulated wires was observed. This result shows that it is possible to effectively suppress the fusion of insulated wires in a bundled state under a high temperature atmosphere by electron beam irradiation, and this effect is achieved by applying electron beam irradiation to water-swellable layered silicate. It shows that it can be obtained in either case. Further, as described above, appearance, adhesion, and bleed-out are not affected by electron beam irradiation.

Example 5 is a case where a high concentration (5% by mass ) is used as an aqueous dispersion of the water-swellable layered silicate, but a case where a low concentration (1% by mass ) is used (Example) 3) and the like (appearance, fixation, bleed out, fusion) are obtained. From this result, it is shown that even if the concentration of the aqueous dispersion of the water-swellable layered silicate is increased, the effect (good appearance and the like) of the present invention is not impaired if it is about 10% by mass or less.

  Comparative Example 1 is a case where no sticking / fusing prevention agent was used, but sticking occurred at the time of winding the reel, and even when the electron beam irradiation treatment was performed, in a high temperature (150 ° C.) atmosphere. Fusion was caused by binding.

  Comparative Example 2 is a case where a layered silicate that is difficult to disperse in water is used as an adhesion / fusion prevention agent. However, since the adhesion / fusion prevention agent is not dispersed in water, white aggregates adhere to the surface. And the appearance was poor. Also, fusion occurred due to binding in a high temperature (150 ° C.) atmosphere.

  Comparative Example 3 is an example in which an insulated wire was prepared by adding oleic acid amide as an antiblocking agent when the insulating layer forming resin composition was prepared by melt kneading. Although the fixation at the time of winding the reel was improved, fusion occurred due to binding in a high temperature (150 ° C.) atmosphere. In addition, bleed-out occurred due to long-term storage, and white aggregates were observed on the insulated wire surface.

(Multi-layer wire (double-layer wire))
Example 6
Under the same conditions as in Example 3, the outer periphery of the base wire was coated with the insulating wire forming resin composition obtained in Production Example 1 and an accelerated electron beam with an acceleration voltage of 2000 kv was applied in an air atmosphere to the coated electric wire. Irradiated to give a crosslinking treatment. Thereafter, the covered electric wire was passed through the water tank filled with the fixing / fusing inhibitor aqueous dispersion (1% by weight aqueous dispersion of the water-swellable layered silicate A) prepared in Production Example 2 for 2 seconds, and further Examples 3 and dried to obtain an insulated wire (outside diameter 5.3 mmφ) coated with water-swellable layered silicate A.

  A 60 mmφ single screw extruder (cylinder temperature average: about 150 ° C.) was used on the outer periphery of the insulated wire thus obtained, and an ethylene-vinyl acetate copolymer as a jacket material was 0.5 mm thick. Extrusion was performed so that the outer diameter was 6.3 mmφ, and a two-layer electric wire for evaluation was obtained.

Comparative Example 4
A two-layer electric wire for evaluation was obtained in the same manner as in Example 6 except that the step of passing the covered electric wire through a water tank filled with the fixing / fusing inhibitor aqueous dispersion was not performed.

Comparative Example 5
Instead of passing the covered wire through a water tank filled with an adhesion / fusing inhibitor water dispersion, it is a dish with talc spread on the dish that is vibrated so that the talc can easily adhere to the wire. A two-layer electric wire for evaluation was obtained in the same manner as in Example 6 except that the step of attaching talc to the electric wire through the covered electric wire so as to touch the talc was performed.

[Evaluation of double-layer wire]
For each of the two-layer electric wires obtained in Example 6 and Comparative Examples 4 to 5, the jacket removal force was measured by the following method. The results are shown in Table 3. Table 3 also shows the evaluation results of the appearance of the insulated wires before the formation of the jacket (results evaluated by the same method and criteria as the above [Evaluation of insulated wires]).

(Coating removal force)
A two-layer electric wire for evaluation was cut to a length of 15 cm, and a 4 cm jacket was removed from each end to prepare a measurement sample. The portion of the insulated wire from which the jacket was removed was passed through a hole having the same size as the insulated wire, and the two-layered wire was fixed to a jig. Using a tensile tester (manufactured by Shimadzu Corporation: Autograph AGI), the insulated wire inside was pulled and pulled out from the jacket, and the pulling force was measured. The pulling force was defined as the jacket removing force. Three measurements were performed and the values are listed in Table 3.

  Example 6 is a two-layer electric wire produced by coating an insulated wire with a water-swellable layered silicate A (adhesion / fusion-preventing agent) that easily swells with water and extruding the outer periphery thereof. The jacket removal force is low and stable. This is presumably because the sticking / fusion preventing agent is evenly applied to the surface of the insulated wire and no sticking / fusion occurs.

  Comparative Example 4 was a case where no fixing / fusing inhibitor was used, and in this case, the outer cover removal force was too high, and it was difficult to remove the outer cover. This is probably because the adhesion between the jacket and the insulating layer of the insulated wire is too strong.

  Comparative Example 5 is a two-layer electric wire produced by applying talc powder instead of coating an insulated electric wire with a water-swellable layered silicate. From the results of Table 3, it is shown that, by coating with talc powder, the jacket removing power is reduced, but the jacket removing power is not stable, and varies, such as being too high or too low. It is considered that it is difficult to uniformly attach the talc powder to the surface of the insulated wire.

It is sectional drawing which shows the structure of the insulated wire of this invention typically. It is sectional drawing which shows the structure of the multilayer electric wire of this invention typically. It is a schematic diagram which shows typically an example of the manufacturing apparatus of the insulated wire of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, Conductor 2, Insulating layer 3, Water-swellable layered silicate 4, Outer sheath 5, Covered wire 10, Insulated wire 11, Manufacturing device 12 for manufacturing insulated wire, Covering device 13, Cooling water tank 14, Prevention of sticking Agent water dispersion tank 15, dryer zone 16, electron beam irradiation device 17, reel 21, unwinding section 23, extruder zone

Claims (2)

Conductor, an insulating layer covering the outer periphery, and the formed on the surface of the insulating layer, have a coating layer of water-swellable phyllosilicate, said water swellable layer silicate, smectite clays, vermiculite based The insulating layer is selected from clay, halloysite, swellable mica, and a mixture thereof, and the insulating layer is made of a resin crosslinked by irradiation with ionizing radiation, and the thickness of the coating layer is 0.03 μm to 10 μm. Insulated wire. A multi-layer electric wire comprising the insulated wire according to claim 1 and a jacket for further covering the water-swellable layered silicate coating layer.

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