JPH06223634A - Multilayer insulated wire and manufacture thereof - Google Patents

Abstract

PURPOSE:To enhance the solderability, peeling property, and electrical insulating property of insulating layers and the coil workability and reliability, etc., of wire by cooling the surface of each extrusion coating layer to 100 deg.C or lower on completion of the extrusion of three predetermined layers. CONSTITUTION:At least three insulating layers 4b(6b), 4c(6c), 4d(6d) are formed over the outer periphery of the conductor 4a(6a) of either one or both of primary and secondary coils 4, 6. The first and second layers 4b(6b) and 4c(6c) of the conductor 4a(6a) are extrusion coating layers, each made from a thermoplastic straight chain polyester resin or the like, the resin being formed by linking aliphatic alcohol components with acid components. The third layer 4d(6d) also is an extrusion coating layer composed mainly of a thermoplastic polyamide resin. On completion of formation of the three extrusion coating layers, the surface of each layer is cooled to 100 deg.C or lower. Thereby the peeling property of the insulating layers becomes excellent and reliability can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layer insulated wire having three or more insulating layers and a method for producing the same. More specifically, the insulating layers are appropriately peeled from each other, and when immersed in a solder bath. Since the insulating layer can be removed in a short time and solder can be attached to the conductor, it has excellent soldering characteristics.
The insulation characteristics of the insulation layer do not easily deteriorate over time, and
The present invention relates to a multilayer insulated electric wire which has excellent coil processability and is useful as a winding wire or a lead wire of a transformer incorporated in an electric / electronic device, etc.

[0002]

2. Description of the Related Art The structure of a transformer is based on the IEC standard (Internat
ional Electrotechnical Communication Standard) Pu
b. 950,65,335,601 etc. That is, in these standards, the enamel coating that covers the conductor in the winding is not recognized as an insulating layer, and at least three insulating layers are formed between the primary winding and the secondary winding, or Thickness should be 0.4mm or more, edge distance between primary and secondary windings should be 5mm or more, depending on the applied voltage, and 300 on primary side and secondary side.
It is specified that the device withstands 1 minute or more when 0V is applied.

For this reason, in the transformers that currently occupy the mainstream seat, the cross-sectional structure illustrated in FIG. 1 is adopted. That is, the bobbin 2 with the collar on the ferrite core 1
The primary winding 4 covered with the enamel is wound in a state where the insulating barriers 3 for securing the edge distance are arranged at both ends of the peripheral surface of the bobbin 2 and then the primary winding 4 is wound.
At least three layers of the insulating tape 5 are wound on the insulating tape layer, and the insulating barrier 3 for securing the edge distance is arranged on the insulating tape layer. Then, the secondary winding 6 also coated with the enamel is wound. It is a rotated structure.

By the way, in recent years, as shown in FIG. 2, a transformer having no insulating barrier 3 or insulating tape layer 5 has begun to appear in place of the transformer having the sectional structure shown in FIG. Compared with the transformer of the structure of FIG. 1, this transformer is
It has the advantages that the entire device can be downsized and that the work of winding the insulating tape can be omitted.

In the case of manufacturing the transformer shown in FIG. 2, in the primary winding 4 and the secondary winding 6 used, at least three insulating layers 4b (on the outer circumference of one or both conductors 4a (6a)). 6b), 4c (6c), and 4d (6d) are formed, and it is necessary that the insulating layers can be separated from each other in relation to the IEC standard.

In such a winding, first, an insulating tape is wound around the outer periphery of a conductor to form a first insulating layer, and then an insulating tape is wound on the second insulating layer, It is known that a third insulating layer is sequentially formed to form an insulating layer having a three-layer structure in which layers are separated from each other (Actual Kaihei 3-1.
No. 06626). Further, there is known a winding in which a fluorine-based resin is sequentially extrusion-coated on the outer circumference of a conductor which is enamel-coated with polyurethane, and an extrusion-coated layer having a three-layer structure is used as an insulating layer as a whole (Actual Publication No. 3-56112). Issue).

[0007]

However, in the case of the former winding, since the winding work of the insulating tape is unavoidable, the production becomes remarkably low, which causes a problem that the manufacturing cost rises. In addition, the latter winding has the advantage that it has good heat resistance because the insulating layer is made of fluorine-based resin, but on the other hand, the adhesion between layers is poor, so it has a high reliability as an insulated wire. There is a problem of lack of sex.

That is, when the insulated wire is coiled, the insulated wire is wound around the coil bobbin while being guided by the guide nozzle. At this time, the insulated wire rubs against the guide nozzle and the insulating layer is peeled off from the conductor. A situation in which the layers of the respective insulating layers are separated easily occurs.
When the electric wire is wound around the coil bobbin in such a state, the insulating layer is broken due to rubbing between the wound insulated electric wires. In such a state, the electrical characteristics of the coil, for example, dielectric breakdown characteristics will be impaired.

Further, in the case of this insulating layer, it cannot be removed even by immersing it in a solder bath.
There is a problem that the insulating layer of the terminal has to be peeled off by a mechanical means with low reliability. In order to solve such a problem, polyethylene terephthalate (PET) resin, which has excellent electric insulation and heat resistance and is easily decomposed at the melting temperature of the solder, is extrusion-coated on the outer periphery of the conductor to form an insulating layer. Is being considered.

However, this PET resin exhibits its original heat resistance and mechanical properties only after being crystallized under appropriate orientation conditions, and when it is coated by extrusion, it has a high crystallinity. Cannot be obtained, and there is still room for improvement in the withstand voltage characteristics over time. Further, in the case of an electric wire in which all of the three insulating layers are formed of the PET resin, there is room for improvement in the insulation characteristics of the coil obtained by coiling the electric wire.

This problem is due to the PE formed as an insulating layer.
Due to the high friction coefficient of the surface of the T-based resin layer, the outermost layer is rubbed against each other due to the action of the winding tension applied to the electric wire during coil processing, and damage such as cracks easily occurs there. Since it is also made of PET resin, it has relatively good adhesion, and it is considered that cracks and the like generated in the outermost layer are likely to spread to the lower insulating layer due to the notch effect.

The present invention solves the above-mentioned problems in the three-layer insulated wire in which the insulating layer is made of PET resin, and the peelability between the insulating layers is appropriate, and the above IEC standard is satisfied. In addition, the deterioration of the electrical insulation of the insulating layer over time is smaller than that of conventional wires, and because the coil workability is even better, the insulation characteristics, etc. are not impaired during coil processing and reliability is improved. It is intended to provide an excellent three-layer insulated wire and a method for manufacturing the same.

[0013]

In order to achieve the above-mentioned object, in the present invention, in a multi-layer insulated wire comprising a conductor and three or more insulating layers covering the conductor, 1 The second and second insulating layers are (a)
An extrusion coating layer of a resin mixture prepared by blending 5 to 40 parts by weight of an ethylene-based copolymer having a carboxylic acid or a metal salt of a carboxylic acid in a side chain with 100 parts by weight of a thermoplastic linear polyester resin (hereinafter, Extrusion coating layer a), (b)
Extrusion coating layer (hereinafter referred to as extrusion coating layer b) containing as a main component a thermoplastic linear polyester resin formed by combining an alcohol component, which is cyclohexanedimethanol in whole or in part, and an acid component, (c) 100 parts by weight of a thermoplastic linear polyester resin formed by combining an alcohol component, which is wholly or partially cyclohexanedimethanol, and an acid component, with respect to 100 parts by weight of an ethylene-based resin having a carboxylic acid or a metal salt of a carboxylic acid in a side chain. Any one of extrusion coating layers (hereinafter referred to as extrusion coating layers c) of a resin mixture prepared by mixing 50 parts by weight or less of the copolymer, wherein the third insulating layer is a thermoplastic polyamide resin or a thermoplastic polyamide. Provided is a multilayer insulated wire, which is an extrusion coating layer of a resin mixture containing a resin as a main component.

Further, in the present invention, 3 is formed on the surface of the conductor.
In the method for producing a multilayer insulated wire in which an insulating layer of at least one layer is formed by extrusion coating, at the time when the extrusion coating of a predetermined layer is completed,
There is provided a method for producing a multilayer insulated wire, which comprises performing an operation of cooling the surface of the extrusion coating layer to 100 ° C. or lower. In the multilayer insulated electric wire of the present invention, 1 from the conductor side
Both the first and second insulating layers may be formed by one kind selected from the extrusion coating layer a, the extrusion coating layer b, and the extrusion coating layer c, but may be formed by another kind.

In this case, the extruded coating layer a as the first and second insulating layers is an insulated electric wire having particularly excellent soldering characteristics (hereinafter referred to as the first electric wire). . In addition, when the first and second insulating layers are the extruded coating layer b or the extruded coating layer c, it becomes an insulated electric wire having excellent heat resistance (hereinafter, referred to as a second electric wire). In the first electric wire and the second electric wire, the resin or resin mixture forming the first insulating layer and the second insulating layer may have different component compositions.

Further, in the first and second insulating layers,
One layer is an extrusion coating layer a and the other layer is an extrusion coating layer b.
Alternatively, when the extruded coating layer c is used, the resulting multilayer insulated wire has a well-balanced soldering property and heat resistance. The resin mixture constituting the extrusion coating layer a contains a thermoplastic linear polyester resin and an ethylene copolymer, which will be described later, as essential components.

Among them, as the thermoplastic linear polyester resin, a resin obtained by an ester reaction of an aromatic dicarboxylic acid or a dicarboxylic acid partially substituted with an aliphatic dicarboxylic acid and an aliphatic diol is used. To be
For example, polyethylene terephthalate resin (PET),
Typical examples are polybutylene terephthalate resin (PBT) and polyethylene naphthalate resin.

Examples of the aromatic dicarboxylic acid used in the synthesis of the thermoplastic linear polyester resin include terephthalic acid, isophthalic acid, terephthaldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylethercarboxylic acid, methylterephthalate. Acid, methyl isophthalic acid, etc. can be mentioned. Of these, terephthalic acid is particularly preferable.

Examples of the aliphatic dicarboxylic acid that partially replaces the aromatic dicarboxylic acid include succinic acid, adipic acid, sebacic acid and the like. The amount of substitution of these aliphatic dicarboxylic acids is the same as that of aromatic dicarboxylic acids.
It is preferably less than 0 mol%, particularly 20 mol%.
It is preferably less than. On the other hand, examples of the aliphatic diol used in the ester reaction include ethylene glycol, trimethylene glycol, tetramethylene glycol, hexanediol and decanediol. Of these, ethylene glycol and tetramethyl glycol are preferable. Moreover, as the aliphatic diol, a part thereof may be oxyglycol such as polyethylene glycol or polytetramethylene glycol.

The other essential component of the resin mixture constituting the extrusion coating layer a is, for example, an ethylene copolymer in which a side chain of polyethylene is bound with a carboxylic acid or a metal salt of a carboxylic acid. This ethylene-based copolymer functions to suppress crystallization of the thermoplastic linear polyester resin described above, thereby suppressing deterioration of the electrical characteristics of the formed insulating layer over time, and This contributes to ensuring good peelability between the second insulating layers.

The carboxylic acid to be bonded is, for example,
Examples thereof include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and phthalic acid. Examples of metal salts thereof include Zn and Na. , K, Mg and the like. As such an ethylene-based copolymer, for example, a part of the carboxylic acid of the ethylene-methacrylic acid copolymer is made into a metal salt, and a resin generally called an ionomer (for example, Himilan; trade name, Mitsui Polychemical Co., Ltd. )), An ethylene-acrylic acid copolymer (for example, EAA; trade name, manufactured by Dow Chemical Co., Ltd.), an ethylene-based graft polymer having a carboxylic acid in a side chain (for example, Admer; trade name, Mitsui Petrochemical Industry ( Co., Ltd.).

In this resin mixture, the blending ratio of the thermoplastic linear polyester resin and the ethylene copolymer is
The latter is set in a range of 5 to 40 parts by weight with respect to the former 100 parts by weight. When the compounding amount of the latter is less than 5 parts by weight, there is no problem in heat resistance of the formed insulating layer, but the effect of suppressing crystallization of the thermoplastic linear polyester resin becomes small, and therefore the insulating layer of the insulating layer is not formed during coil processing. The so-called crazing phenomenon in which minute cracks occur on the surface frequently occurs. Further, the deterioration of the insulating layer with time progresses, causing a significant decrease in the dielectric breakdown voltage. On the other hand, the compounding amount is 40
When the amount is more than the weight part, the heat resistance of the insulating layer is significantly deteriorated. The preferable mixing ratio of both is 100 parts by weight of the former and 7 to 25 parts by weight of the latter.

Next, the material constituting the extrusion coating layer b is
It is a thermoplastic linear polyester resin as described below.
That is, it is a linear polyester resin formed by condensing an alcohol component, which is cyclohexanedimethanol, which is an alicyclic alcohol, in whole or in part, and specifically, a polycyclohexanedimethane terephthalate resin (PCT). ) Can be given. This resin has heat resistance superior to that of PET described above.

Considering suppression of a decrease in dielectric breakdown voltage due to deterioration of the insulating layer with time, examples of the modified resin include polyamide resin, polycarbonate resin,
It is preferable to add 10 to 100 parts by weight of a polyurethane resin or the like to 100 parts by weight of the thermoplastic linear polyester resin. Examples of such a PCT resin include EKTAR-DN, EKTAR-DA, and EKTAR.
-GN (trade name, manufactured by Toray Industries, Inc.) can be preferably used.

The resin mixture constituting the extrusion coating layer c is a resin mixture of the above-mentioned PCT resin and an ethylene copolymer which is an essential material in the resin mixture used for forming the extrusion coating layer a. is there. In this resin mixture, PCT
The mixing ratio of the base resin and the ethylene copolymer is 10
The latter is set to 50 parts by weight or less with respect to 0 parts by weight.

If the amount of the latter compounded is more than 50 parts by weight, the excellent heat resistance of the PCT resin will be deteriorated and the heat resistance of the formed insulating layer will be problematic. The preferable blending ratio of both is 5 to 30 parts by weight of the latter with respect to 100 parts by weight of the former. The third insulating layer in the multilayer insulated wire of the present invention is formed of a thermoplastic polyamide resin or a resin mixture containing the thermoplastic polyamide resin as a main component. The third insulating layer has a relatively small friction coefficient on the surface and is excellent in mechanical strength, so that damage such as cracks in the outermost layer during coil processing of the electric wire can be minimized. . In addition, since the adhesiveness to the second insulating layer (polyester resin layer) is low, even if the outermost layer is damaged, the damage is prevented from spreading to the second insulating layer. As a result, it is possible to prevent deterioration of the insulation characteristics after the coil processing.

Further, the third insulating layer is used in the case where the amount of the polyethylene-based copolymer compounded at the time of forming the extrusion coating layer a or the extrusion coating layer c is small, or in the extrusion coating layer b or the extrusion coating layer c. It also has a function of alleviating the deterioration with time of the dielectric breakdown voltage, which tends to occur when the amount of the alcohol component cyclohexanedimethanol used when producing the PCT resin used is small.

As the thermoplastic polyamide resin, for example, 4-nylon, 6-nylon, 10-nylon, 1
1-nylon, 12-nylon, 4,6-nylon,
Examples thereof include 6,6-nylon, 6,10-nylon, 6,12-nylon, and copolymerized nylon thereof (all are trade names manufactured by DuPont). Especially,
4,6-Nylon is preferable because it has excellent heat resistance.

In addition, for example, in these polyamide resins,
One or more of ethylene-methacrylic acid copolymer, ethylene-acrylic acid copolymer, polyethylene, the above-mentioned thermoplastic linear polyester resin, polyurethane resin and polycarbonate resin may be mixed. In this case, the mixing ratio is preferably 3 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin.

In the electric wire of the present invention, each of the first and second insulating layers has 100% by weight of PCT resin substituted by 60 mol% or more of cyclohexane dimethanol with a side chain of carbon. A resin mixture prepared by mixing 20 parts by weight or less of a polyethylene-based copolymer having a Zn salt of an acid and a third insulating layer formed of 4,6-nylon has a heat resistance class of electric wire of E It is useful because it can be improved from the seed (120 ° C.) level to the type B (130 ° C.) level.

In the multilayer insulated wire of the present invention, the outer periphery of the conductor is extrusion-coated with the resin or resin mixture for the first layer to form the first insulating layer having a desired thickness, and then the first layer. A resin or resin mixture for the second layer is extrusion-coated on the outer periphery of the insulating layer to form a second insulating layer having a desired thickness.
It is manufactured by extrusion-coating the outer periphery of the third insulating layer with a polyamide resin for the third layer to form the third insulating layer having a desired thickness.

At this time, the resin mixture used for the extrusion coating of the first layer and the second layer may have the same composition for each layer, or the components may be mixed within the above-mentioned permissible compounding ratio. The composition may be changed. The total thickness of the three insulating layers formed is 100 μm.
It is preferable to control the thickness below, and if the thickness of the second insulating layer is twice or more the thickness of the thicker one of the other insulating layers, the electrical characteristics specified by IEC standard 950 can be easily realized. can do.

Furthermore, when forming each extrusion coating layer forming the insulating layer, the surface of the extrusion coating layer is formed by a method such as water cooling or air cooling when the extrusion coating of the lower layer is completed.
It is effective to form the upper extrusion coating layer after cooling to 00 ° C. or lower, since the peelability between the upper and lower extrusion coating layers is improved. This cooling operation is particularly preferably performed at the time when the extrusion coating of the first layer is completed.

In the multi-layer insulated wire of the present invention, since all three or more insulating layers are formed by the extrusion coating method of the resin mixture, the productivity at the time of production becomes very high. Further, the delamination property is good, and at the time of processing the terminal, direct soldering can be performed. In the first and second insulating layers, the base resin such as polyester resin or P
Crystallization of the CT-based resin is suppressed, so that the electrical characteristics of the insulating layer are not easily deteriorated.

Furthermore, since the outermost layer of the multi-layer insulated wire of the present invention is formed of polyamide resin or a resin mixture containing it as a main component, the coefficient of friction of the outer surface is small, and therefore the outermost layer during coil processing is used. Damage to the outer layer is suppressed. Further, deterioration with time of the first layer and the second layer is also alleviated.

[0036]

Examples of the invention

Examples 1 to 3 and Comparative Examples 1 to 7 The components shown in Table 1 were kneaded in the indicated proportions (parts by weight) to prepare a resin mixture for each extrusion coating layer. An annealed copper wire having a wire diameter of 0.6 mm is prepared as a conductor, and the outer periphery thereof is extrusion-coated with the above-mentioned resin mixture to form a first extrusion coating layer with the indicated thickness, and then a second extrusion coating. A layer was formed, and the outer periphery of the second layer was extrusion-coated with the above resin mixture to produce a three-layer insulated wire.

When manufacturing the product of Example 1, the surface after each extrusion coating was water-cooled to 100 ° C. or lower. Further, each insulating layer of the electric wire of Comparative Example 4 is formed by winding the indicated insulating film.

[0038]

[Table 1]

With respect to the above 9 kinds of 3-layer insulated wires, various characteristics were measured with the following specifications. Solderability: The temperature of the end of the wire about 40mm is 400 ℃
Immerse in the molten solder, and measure the time (seconds) until the solder adheres to the immersed 30 mm portion. The shorter this time is, the better the solderability is.

Electrical insulation: For each of the two-layer and three-layer coatings immediately after production, a bare copper wire is used on one side according to the two-strand method measured by JISC3003, and the dielectric breakdown voltage at that time is measured. . The electric wire coated with three layers was left in the atmosphere for one year, and then the dielectric breakdown voltage was measured by the same method as above to examine the change over time in the electrical insulation property.

Heat resistance: JISC for 3-layer coated wire and bare copper wire
Twist two in accordance with 3003, in that state, the temperature 20
After heat treatment at 0 ° C for 7 days, measure the dielectric breakdown voltage. The larger this value is, the better the heat resistance is. Crazing resistance: After the wire is left in the atmosphere for 6 months, the wire is aligned and mechanically wound on a coil reel having a diameter of 12 mm, and it is observed whether or not crazing occurs on the surface of the wire.

Delamination: About 50 cm in the longitudinal direction of the insulating layer
After cutting it with a cutter knife, make a notch along the entire circumference in the circumferential direction of the wire, fix one end of the wire to the twister and sandwich the other end with the chuck of the twister to fix the wire. It was held straight, the chuck was rotated in this state, the electric wire was twisted in the longitudinal direction, and the number of rotations at which the three insulating layers were separated into each layer was examined. The peeling is performed at the time when a part of the coating film in the cut portion in the circumferential direction can be peeled off. The smaller the number of rotations, the better the delamination property.

Coil workability: A wire is aligned and wound (50 turns) on a conductive square core having a square cross section with a side of 7 mm while applying a tension of 6 kg using a processing machine, and between the wire and the square core. Measures the time until dielectric breakdown occurs when a voltage of 3000 V is applied to. This test has 10 coils each
The results are evaluated by the average value. The longer this time is, the less the insulating layer is damaged during coil processing, that is, the better the coil processability is. The guide nozzle used had a tip hole diameter larger than the outer diameter of the electric wire by 0.05 mm, and the linear velocity was set to 20 m / min.

Observation of appearance after winding: Similar to the case of the coil workability test, the coils were processed by aligning and winding, and for each of the obtained 10 coils, the electric wire was unwound from the square core and the surface thereof was removed. It was observed and the number of breakages in the insulating layer was examined. The above results are collectively shown in Table 2.

[0045]

[Table 2]

The following is clear from Table 2. 1) The first and second layers are formed by a resin mixture composed of an ethylene-based copolymer having a carboxylic acid or the like in the side chain (hereinafter referred to as a modifier) and a thermoplastic polyester resin, and the third layer is formed by heat. Examples 1-5 formed of a plastic polyamide resin
The insulated wire of (3) has particularly excellent soldering characteristics and other characteristics.

Also, in the case of the insulated wire of the above-mentioned corner examples, in the above-mentioned delamination test, delamination first occurs in the third and second layers, and then in the first layer. Then, the second layer was peeled from the insulating layer. This means that when an external force is applied to the wire, the insulating layer is peeled from the outside and is prevented from peeling toward the inside. Therefore, the electric wires of these examples have high reliability.

2) At the time of production, the insulated electric wire of Example 1 provided with a step of water cooling after extrusion coating is excellent in delamination. 3) The insulated wire of Comparative Example 1 in which the thermoplastic polyester resin alone was used to form the first layer and the second layer without blending the above-described modifier, the characteristics of the insulated wire changed significantly with time. Also, the coil processability is poor. The poor coil processability is considered to be because the outermost layer is formed of the thermoplastic linear polyester resin.

4) On the other hand, the insulated wire of Comparative Example 2 formed by using the resin mixture containing the modifier in an excess amount (50 parts by weight) has poor heat resistance. 5) In Comparative Example 3, in addition to the first and second layers, the third layer also has an insulating layer formed of a thermoplastic polyester resin containing a modifier. Since the third layer of this insulated wire is not formed of the thermoplastic polyamide resin, the coil workability is poor.

6) The insulated wire of Comparative Example 4 in which a film is wound to form an insulating layer cannot be soldered. Also, the breakdown voltage is low and the insulation characteristics are poor. Further, the outermost layer has irregularities, and the result of the coil processability is also poor. 7) The insulated wire of Comparative Example 5 in which the insulating layer is formed of a completely different resin (Teflon) cannot be soldered. Further, the interlayer peelability is 8 times, and the adhesion between layers is too bad.

8) The wire of Comparative Example 6 in which the first and third insulating layers are made of polyamide resin has poor coil processability. This is because the adhesion between the insulating layer and the conductor is not good, and the different types of resin are in contact with the first and second layers, and the second and third layers, respectively. Is considered to be very bad. The electric wire of Comparative Example 6 has a low dielectric breakdown voltage. It is considered that this is because there are two insulating layers made of polyamide resin.

9) The electric wire of Comparative Example 7, in which the second and third layers are made of polyamide resin, has poor dielectric breakdown characteristics as in Comparative Example 6. Examples 6 to 8 and Comparative Examples 8 and 9 The components shown in Table 3 were kneaded at the indicated ratios to prepare resin blends for each extrusion coating layer.

An annealed copper wire having a wire diameter of 0.6 mm is prepared as a conductor,
The above resin mixture is extrusion-coated on the outer periphery thereof to form the first extrusion coating layer with the indicated thickness, and then the second extrusion coating layer is formed. The mixture was extrusion coated to produce a 3-layer insulated wire. In addition, when manufacturing Examples 6 and 7, after each extrusion coating step, the surface thereof was water-cooled to 100 ° C. or less.

[0054]

[Table 3]

With respect to these three-layer insulated wires, Examples 1 to 1
Various characteristics were measured with the same specifications as in No. 5. However, the heating temperature in the heat resistance test was set to 230 ° C. The above results are shown in Table 4.

[0056]

[Table 4]

The following is clear from Table 4. 1) Example 6 in which the first and second layers were formed of PCT resin
The insulated wires of Nos. 8 to 8 have excellent characteristics. Particularly, good results were obtained even though the heat resistance test was conducted at a high temperature of 230 ° C.
It is understood that is excellent in heat resistance. The insulated wires of Examples 6 to 8 were peeled off from the outer insulating layer in the same manner as in Examples 1 to 5.

2) In Example 6, the first layer and the second layer were formed of the PCT resin alone, but they showed good characteristics. When a PCT resin is used, the problem of aging can be ignored without blending the above-mentioned modifier (Comparative Example 1 above).
reference). However, in order to obtain such good characteristics, it is considered necessary to form the third layer with a thermoplastic polyamide resin (see Comparative Example 8).

3) The insulated wires of Examples 6 and 7 in which the cooling step was provided after extrusion coating have excellent delamination properties. 4) The insulated wire of Comparative Example 8 in which the outermost layer was formed of PET resin showed a large change with time. It is considered that this is because the outermost layer is formed of the PET resin instead of the polyamide resin, so that the deterioration of the PCT is likely to proceed. Moreover, this was inferior in coil workability.

5) The insulated wire of Comparative Example 7 in which the modifier was excessively blended had a low heat resistance.

[0061]

As is clear from the above description, the multilayer insulated wire of the present invention has high productivity at the time of manufacture because all the insulating layers are formed by extrusion coating, and the insulating layers are soldered. It has excellent characteristics, heat resistance, crazing resistance, delamination resistance, and electrical insulation, and its characteristics do not deteriorate over time. Therefore, it is useful as a winding wire or lead wire for a transformer with a new structure that satisfies the IEC standard. Since the outermost layer is a coating layer containing a polyamide resin as a main component, its friction coefficient is small. Therefore, during coil processing, the outermost layer is less likely to be damaged, and deterioration of insulation characteristics after coil processing is less likely to occur. Moreover, according to the method of the present invention, a multilayer insulated wire can be efficiently manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a transformer having a conventional structure.

FIG. 2 is a cross-sectional view showing an example of a transformer having a structure having a three-layer insulated wire as a winding wire.

[Explanation of symbols]

 1 Ferrite Core 2 Bobbin 3 Insulation Barrier 4 Primary Winding 4a Conductors 4b, 4c, 4d Insulation Layer 5 Insulation Tape 6 Secondary Winding 6a Conductors 6b, 6c, 6d Insulation Layer

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[Procedure amendment]

[Submission date] December 28, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

3. The multi-layer insulated wire according to claim 1, wherein both the first insulating layer and the second insulating layer are the extruded coating layer of (a).

Wherein said first insulating layer and second insulating layer are both, the (b) or (c) the multilayer insulated wire of claim 1 wherein the extruded covering layer.

Wherein said thickness of the second insulating layer, said first insulating layer or three-layer or thicker at least twice a first aspect of the multilayer insulated wire of the thickness of the insulating layer .

Wherein said third insulating layer, the multilayer insulated wire of claim 1 consisting of 4,6-nylon.

7. The electric wire is held linearly in a state in which a cut along the longitudinal direction of the electric wire and a cut along the circumferential direction are engraved in an insulating layer, and the electric wire is held with the longitudinal direction of the electric wire as a central axis. The multi-layer insulated wire of claim 1, wherein when twisted, the layers of the insulating layer separate from each other before the conductor breaks.

8. In a method for producing a multilayer insulated wire in which three or more insulating layers are formed on a surface of a conductor by extrusion coating, the surface of the extrusion coating layer is formed by 10 when the extrusion coating of a predetermined layer is completed.
A method for producing a multilayer insulated wire, which comprises performing an operation of cooling to 0 ° C. or lower.

When producing the multilayer insulated wire 9. claim 1, after forming by a first insulating layer from the conductor side extrusion coated, the operation of cooling the surface of the insulating layer 100 ° C. or less A method for producing a multi-layer insulated wire, which comprises performing.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction content]

[0002]

2. Description of the Related Art The structure of a transformer is based on the IEC standard (Internat
ional Electrotechnical Communication Standard) Pu
b. 950,65,335,601 etc. That is, in these standards, the enamel coating that covers the conductor in the winding is not recognized as an insulating layer, and at least three insulating layers are formed between the primary winding and the secondary winding, or it thickness is 0.4mm or more, along plane distance of the primary and secondary windings also differ by an applied voltage, it is 5mm or more, the primary side and the secondary side 300
It is specified that the device withstands 1 minute or more when 0V is applied.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

For this reason, in the transformers that currently occupy the mainstream seat, the cross-sectional structure illustrated in FIG. 1 is adopted. That is, the bobbin 2 with the collar on the ferrite core 1
Is fitted, after the primary winding 4 which is enamelled is wound in a state in which an insulating barrier 3 is arranged to ensure along surface distance on the peripheral surface side end of the bobbin 2, the primary winding 4
Over, turning at least three layers wound insulating tape 5, further After disposing an insulating barrier 3 for securing along surface distance on the insulating tape layer, likewise enamelled secondary winding 6 is wound It is a rotated structure.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

The present invention solves the above-mentioned problems in the three-layer insulated wire in which the insulating layer is made of PET resin, and the peelability between the insulating layers is appropriate, and the above IEC standard is satisfied. In addition, the deterioration of the electrical insulation of the insulating layer over time is smaller than that of conventional wires, and because the coil workability is even better, the insulation characteristics, etc. are not impaired during coil processing and reliability is improved. and an object thereof is to provide a multi-layer insulated wire and a manufacturing method thereof are excellent.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

[0013]

In order to achieve the above-mentioned object, in the present invention, in a multi-layer insulated wire comprising a conductor and three or more insulating layers covering the conductor, 1 The second and second insulating layers are (a)
Ethylene copolymer 5 having a carboxylic acid or a metal salt of a carboxylic acid in a side chain with respect to 100 parts by weight of a thermoplastic linear polyester resin formed by combining an aliphatic alcohol component and an acid component. Extruded coating layer (hereinafter referred to as extruded coating layer a) of a resin mixture prepared by blending 40 to 40 parts by weight, (b)
An extruded coating layer (hereinafter referred to as extruded coating layer b) whose main component is a thermoplastic linear polyester resin formed by binding an alicyclic alcohol component and an acid component in whole or in part.
(C) Ethylene having a carboxylic acid or a metal salt of a carboxylic acid in its side chain with respect to 100 parts by weight of a thermoplastic linear polyester resin formed wholly or partially in combination with an alicyclic alcohol component and an acid component. Which is one of the extruded coating layers (hereinafter referred to as extruded coating layers c) of a resin mixture prepared by blending 50 parts by weight or less of a system copolymer, wherein the third insulating layer is
Provided is a multilayer insulated wire, which is an extrusion coating layer of a thermoplastic polyamide resin or a resin mixture containing a thermoplastic polyamide resin as a main component.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

Among them, as the thermoplastic linear polyester resin , an aromatic dicarboxylic acid which is an acid component or a dicarboxylic acid in which a part thereof is substituted with an aliphatic dicarboxylic acid and an aliphatic diol which is an aliphatic alcohol component are used. What was obtained by the ester reaction of is used. Representative examples include polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PBT), and polyethylene naphthalate resin.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

Examples of the carboxylic acid bonded to the side chain of polyethylene include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, maleic acid,
Unsaturated dicarboxylic acids such as fumaric acid and phthalic acid can be mentioned, and examples of these metal salts include Zn, N
Salts such as a, K, and Mg can be used. As such an ethylene-based copolymer, for example, a part of the carboxylic acid of the ethylene-methacrylic acid copolymer is made into a metal salt, and a resin generally called an ionomer (for example, Himilan; trade name, Mitsui Polychemical Co., Ltd. )), An ethylene-acrylic acid copolymer (for example, EAA; trade name, manufactured by Dow Chemical Co., Ltd.), an ethylene-based graft polymer having a carboxylic acid in a side chain (for example, Admer; trade name, Mitsui Petrochemical Industry ( Co., Ltd.).

[Procedure Amendment 8]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

Next, the material constituting the extrusion coating layer b is
All or part of the alicyclic alcohol component and the acid component are combined.
It is a thermoplastic linear polyester resin formed by the combination. Among them preferred are heat formed by condensing all or a portion starve Kurohe <br/> Kisanjimetano Le an acid component
A thermoplastic linear polyester resin, specifically, poly cyclohexane dimethylene terephthalate resin (PC
T) can be raised. This resin is PET
It has better heat resistance than

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

Considering suppression of a decrease in dielectric breakdown voltage due to deterioration of the insulating layer with time, examples of the modified resin include polyamide resin, polycarbonate resin,
The polyurethane resin, it is preferable to blend 10 to 100 parts by weight per 100 parts by weight of the thermoplastic linear polyester resin. As such a PCT resin,
For example, EKTAR-DN, EKTAR-DA, EKT
AR-GN (trade name, manufactured by Toray Industries, Inc.) can be preferably used.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

The resin mixture constituting the extrusion coating layer c is, for example,
For example, it is a resin mixture of the above-mentioned PCT resin and an ethylene copolymer which is an essential material in the resin mixture used for forming the extrusion coating layer a. In this resin mixture,
The mixing ratio of the PCT resin and the ethylene copolymer is set to 50 parts by weight or less with respect to 100 parts by weight of the former.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Further, the third insulating layer is used in the case where the amount of the polyethylene-based copolymer compounded at the time of forming the extrusion coating layer a or the extrusion coating layer c is small, or in the extrusion coating layer b or the extrusion coating layer c. It also acts to mitigate the deterioration with time of the dielectric breakdown voltage that tends to occur when the amount of the resin used , for example, the alicyclic alcohol component used when manufacturing the PCT-based resin , such as cyclohexanedimethanol is small. .

[Procedure Amendment 12]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

In the electric wire of the present invention, the first and second insulating layers are both PCT-based in which the alicyclic alcohol component, especially cyclohexanedimethanol is substituted by 60 mol% or more. It is made of a resin mixture in which 20 parts by weight or less of a polyethylene copolymer having a Zn salt of a carboxylic acid in a side chain is mixed with 100 parts by weight of a resin, and a third insulating layer is made of 4,6-nylon. These are useful because they can improve the heat resistance class of electric wires from the class E (120 ° C) level to the class B (130 ° C) level.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

In the multi-layer insulated wire of the present invention, since all three or more insulating layers are formed by the extrusion coating method of the resin mixture, the productivity at the time of production becomes very high. Further, the delamination property is good, and at the time of processing the terminal, direct soldering can be performed. The first layer, the second insulating layer, poly <br/> ester trees crystallization of fat PCT resins as the base resin is suppressed, therefore, the deterioration of such electric properties of the insulating layer very Hard to happen.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction content]

[0038]

[Table 1]

[Procedure Amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction content]

The electrically insulating: 2-layer coated immediately after production, per each wire of a three-layer coating, using a bare copper wire to one according to two twisting method of stipulated in JISC3003, the breakdown voltage at that time Measurement. The electric wire coated with three layers was left in the atmosphere for one year, and then the dielectric breakdown voltage was measured by the same method as above to examine the change over time in the electrical insulation property.

[Procedure Amendment 16]

[Document name to be amended] Statement

[Name of item to be corrected] 0058

[Correction method] Change

[Correction content]

2) In Example 6, the first layer and the second layer were formed of the PCT resin alone, but they showed good characteristics. When using a PCT-based resin, it can be largely ignored the problem of aging (see Comparative Example 1). However, in order to obtain such good characteristics, it is considered necessary to form the third layer with a thermoplastic polyamide resin (see Comparative Example 8).

[Procedure Amendment 17]

[Document name to be amended] Statement

[Correction target item name] 0060

[Correction method] Change

[Correction content]

5) Comparative example in which the modifier is excessively blended
In the insulated wire of No. 9 , the heat resistance is lowered.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI technical display location C08L 23:26) (72) Inventor Isamu Kobayashi 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Industry Co., Ltd. (72) Inventor Mitsuru Inoue 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Nobuyuki Nakamura 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Industry Co., Ltd.

Claims (8)

[Claims] 1. A multilayer insulated electric wire comprising a conductor and three or more insulating layers covering the conductor, wherein the first and second insulating layers from the conductor side are (a) a thermoplastic linear polyester resin. An extrusion coating layer of a resin mixture obtained by blending 5 to 40 parts by weight of an ethylene-based copolymer having a carboxylic acid or a metal salt of a carboxylic acid in a side chain with respect to 100 parts by weight, and An extrusion coating layer containing a thermoplastic linear polyester resin as a main component, which is formed by combining an alcohol component which is cyclohexanedimethanol and an acid component, (c) An alcohol component and an acid which are wholly or partially cyclohexanedimethanol Ethylene copolymer 50 having carboxylic acid or metal salt of carboxylic acid in side chain with respect to 100 parts by weight of thermoplastic linear polyester resin formed by combining components Which is one of a resin mixture extruded coating layer formed by blending parts by weight or less, wherein the third insulating layer is
A multilayer insulated electric wire, which is an extrusion coating layer of a thermoplastic polyamide resin or a resin mixture containing a thermoplastic polyamide resin as a main component. 2. The multilayer insulated wire according to claim 1, wherein both the first insulating layer and the second insulating layer are the extruded coating layer of (a). 3. The multi-layer insulated wire according to claim 1, wherein the first insulating layer and the second insulating layer are both extruded coating layers of (b) or (c). 4. The multi-layer insulated wire according to claim 1, wherein the thickness of the second insulating layer is at least twice the thickness of the thicker insulating layer of the first insulating layer or the third insulating layer. . 5. The multilayer insulated wire according to claim 1, wherein the third insulating layer is made of 4,6-nylon. 6. The electric wire is held linearly in a state in which a cut along the longitudinal direction of the electric wire and a cut along the circumferential direction are formed in the insulating layer, and the electric wire is held with the longitudinal direction of the electric wire as a central axis. The multi-layer insulated wire of claim 1, wherein when twisted, the layers of the insulating layer separate from each other before the conductor breaks. 7. A method for producing a multi-layer insulated wire in which three or more insulating layers are formed on the surface of a conductor by extrusion coating, and when the extrusion coating of a predetermined layer is completed, the surface of the extrusion coating layer is made 10
A method for producing a multilayer insulated wire, which comprises performing an operation of cooling to 0 ° C. or lower. 8. When manufacturing the multi-layer insulated wire according to claim 1, an operation of cooling the surface of the insulating layer to 100 ° C. or lower after forming the first insulating layer by extrusion coating from the conductor side. A method for producing a multi-layer insulated wire, which comprises performing.