JPH05298934A - Insulated wire - Google Patents

Abstract

PURPOSE:To improve a low abrasion factor, abrasion resistance, and heat resis tance, by providing a sliding coating layer on the outermost layer with paint, to which a given quantity of spherical grains of crosslinked polymethyl methacrylate having a mean particle diameter of 10mum or smaller, is added, applied and baked. CONSTITUTION:A sliding coating layer 2, obtained by applying and baking paint to which 0.1-10wt.% of the true spherical grains of crosslinked methyl polymethacrylate having a mean particle diameter of 10mum or smaller is added to the resin part of paint, is provided on the outermost layer. That is, a sliding coating layer 2 is provided on the outer peripheral surface of a conductor 1, and this layer 2 is composed by applying and baking a substance, to which the spherical grains of the crosslinked polymethyl methacrylate is added to insulating paint, on the conductor 1, and doubles as an insulating layer. Because of the uniform dispersed-existence of grains in the layer 2, a low abrasion factor is provided, abrasion resistance is excellent, also sticking force at the time of coil impregnation becomes good, and also heat resistance can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated electric wire used in a wide range of applications as an electric wire for a coil of equipment such as electric and communication equipment, and has an outermost coating layer provided with excellent lubricity. is there.

[0002]

2. Description of the Related Art Insulated wires are damaged by nozzles, pulleys, etc. in the winding process during the manufacturing of the above-mentioned equipment coils, which causes a layer short circuit and a ground failure. Especially with the recent increase in winding speed,
Since the insulated wire is wound under severe conditions, the above phenomenon tends to occur frequently, and it has been desired to solve this problem. As a means for preventing the occurrence of such scratches, it is necessary to reduce the friction coefficient of the winding and increase the wear resistance. For this reason, conventionally, an insulated wire coated with lubricating oil or coated with a synthetic resin having a low friction coefficient such as nylon or polyethylene has been used.

However, the former cannot follow the increase in the winding speed and does not contribute to solving the problem. In the latter case, the number of synthetic resin coating processes increases, the heat resistance decreases depending on the compatibility with the insulation coating, and when coil impregnation is performed after winding, the temperature range from room temperature to the actual high temperature However, there was a drawback that the adhesion strength was lowered.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an insulated wire having a low wear coefficient, excellent wear resistance, and heat resistance.

[0005]

The object of the present invention is to coat and bake a coating in which spherical spherical fine particles of crosslinked polymethylmethacrylate having an average particle diameter of 10 μm or less are added in an amount of 0.1 to 10% by weight based on the resin content of the coating. This is solved by providing the slippery coating layer obtained in this way as the outermost layer.

The present invention will be described in detail below. Figure 1
Shows a first example of the insulated wire of the present invention.
Reference numeral 1 in the figure is a conductor made of copper, copper alloy, aluminum, aluminum alloy or the like. A slippery coating layer 2 is provided on the outer peripheral surface of the conductor 1. This slippery coating layer 2
Is an insulating coating material to which true spherical fine particles of cross-linked poly (methyl methacrylate) are added and applied onto the conductor 1 and baked, and also serves as an insulating layer.

As the above-mentioned insulating paint, epoxy, modified epoxy, acrylic, polyamide, polyvinyl formal, modified polyvinyl formal, polyurethane, polyester, modified polyester, polyesterimide, modified polyesterimide, polyhydantoin, polyimidazopyrrolone, polyamideimide, polyimide , Modified polyimide and the like.

The true spherical fine particles of crosslinked poly (methyl methacrylate) added here are those obtained by cross-linking polymerization of methyl methacrylate monomer by a special suspension polymerization method, and their outer shapes are true spherical. The particles are not blocked with each other, are excellent in fluidity and slipperiness, and are also excellent in heat resistance, weather resistance, and chemical resistance. In this invention,
Among these fine particles, those having an average particle diameter of 10 μm or less are selected and used. If the average particle size exceeds 10 μm, the appearance of the insulated wire is deteriorated, which is not preferable, and a good result in terms of lubricity cannot be obtained.

Specific examples of such spherical fine particles of crosslinked poly (methyl methacrylate) include "Techpolymer MBX-4" and "Techpolymer MBX-8" (trade name,
Sekisui Plastics Co., Ltd., etc. The amount of the spherical particles added to the insulating paint is in the range of 0.1 to 10% by weight based on the resin content of the paint. The addition amount is 1
If it exceeds 0% by weight, the appearance of the electric wire will be deteriorated and it will be difficult to fix it with the impregnated varnish. If it exceeds 0.1% by weight, improvement in wear resistance will not be observed. The preferable addition amount is 0.5 to 5.0% by weight.

The thickness of the above-mentioned lubricous coating layer 2 is usually 1
The thickness is in the range of about 0 to 100 μm and also serves as the insulating layer, so it is preferable to make the thickness a little thicker, but it is not limited to the above range.

Further, in the present invention, as shown in FIG.
Insulating layer 3 provided directly on conductor 1 with lubricious coating layer 2 in which spherical particles of crosslinked polymethylmethacrylate are dispersed.
It can also be provided via. This is because in the insulated wire shown in FIG. 1, since the slippery coating layer 2 is formed directly on the conductor 1, the adhesion with the conductor 1 tends to be slightly reduced. In this respect, since the insulated wire shown in FIG. 2 is coated and baked through the insulating layer 3, sufficient adhesion with the conductor 1 can be ensured, which is preferable. In this case, the film thickness ratio between the insulating layer 3 and the lubricous coating layer 2 is approximately 10: 1 to 10: 5.
It is preferable that

In such an insulated wire, since the spherical particles of crosslinked polymethylmethacrylate are uniformly dispersed in the lubricous coating layer 2, it has a low friction coefficient and It has excellent wear properties, and also has good adhesion when the coil is impregnated. In particular, since the shape of the fine particles is spherical, the dispersibility in the insulating coating is good, and even in the slippery coating layer 2 after baking, the particles are present in a uniformly dispersed state without agglomeration.
As a result, the abrasion resistance is improved and the coefficient of friction is remarkably reduced, and further, the flexible coating layer 2 is not cracked or cracked when the insulated wire is bent.

FIG. 3 shows a second example of the insulated wire of the present invention. The insulated wire of this example is provided with an insulating layer 3 formed by applying and baking an ordinary insulating coating on the conductor 1, and on the insulating layer 3, a cross-linked poly (methyl methacrylate) having an average particle diameter of 10 μm or less is formed. This is a so-called self-fusing insulated wire provided with a self-fusing slipping coating layer 4 which is in a semi-cured state (B stage) by applying and baking a coating material containing true spherical particles.

As the coating material for obtaining the slip coating layer 4 having the self-fusing property, a linear polymer compound such as a phenoxy resin, a polyvinyl butyral resin, a polyvinyl formal resin or a copolyamide resin may be used alone or 2 A combination of more than one kind, or epoxy resin,
Stabilized isocyanates, urea resins, melamine resins, acetoguanamine resins, aniline resins, benzoquanamine resins, and other amino resins, or alcohol-modified amino resins obtained by modifying these with alcohol, condensates with phenol / cresol / xylenol, para-vinylphenol, etc. The above-mentioned phenol resin or the like is used alone or a mixture of two or more thereof is used. In this case, the amount of the spherical particles added is 0.1 to 10% by weight based on the resin content in the coating as before, and if the amount is less than 0.1% by weight, the wear resistance is hardly improved. If it exceeds 10% by weight, the adhesive strength at high temperature decreases and the heat-resistant life property deteriorates.

In such a self-adhesive insulated wire, the semi-cured and relatively self-adhesive self-adhesive layer has extremely good lubricity, so that scratches and the like during winding are significantly caused. Will be reduced. Further, the adhesive force between the windings does not decrease due to the presence of the spherical particles.

Hereinafter, the working effects will be clarified by showing examples. (Example 1) A copper wire having a diameter of 0.5 mm was coated with a polyester imide paint (manufactured by Dainichiseika Kogyo Co., Ltd.) and baked to obtain a film thickness of 1
A polyesterimide wire having a 7 μm insulating layer was prepared. On the other hand, the above-mentioned polyester imide coating was prepared by adding "Techpolymer M" as spherical fine particles of cross-linked poly (methyl methacrylate).
BX-4 "(average particle size 4 μm, Sekisui Plastics Co., Ltd.)
(A) 0 wt% (b) 0.5 wt% (c) 1 wt% (d) 5 wt% (e) 10 wt% (f) 15 wt% Was coated and baked on the insulating layer to form a 3 μm slipping coating layer.

Regarding these insulated wires, flexibility (self-diameter, JISC3003, 8), thermal softening temperature (JISC3
003,12), reciprocating wear (former JISC3003,1
0), the adhesive force with the impregnated varnish was measured. The adhesion strength with the impregnated varnish was measured by winding an electric wire around a mandrel having a diameter of 5 mm for 20 turns, impregnating it with an ester imide-based impregnating varnish, and then heat curing at 200 ° C. for 2 hours to give a test piece. It was evaluated by the peeling force when both ends were pulled and peeled off. The results are shown in Table 1.

[0018]

[Table 1]

As is clear from the results shown in Table 1, this insulated wire has excellent lubricity, which is represented by reciprocal wear, and is flexible and has a high fixing force with the impregnated varnish.

(Example 2) 22 parts by weight of a phenoxy resin and 50 parts of an alcohol-modified melamine-formaldehyde condensate are placed through an insulating layer obtained by coating and baking polyesterimide having a film thickness of 20 μm on a copper wire having a diameter of 0.5 mm. A 16% by weight solution of 62% by weight was dissolved in 62 parts by weight of cyclohexanone.
"Techpolymer MBX-4" as true spherical fine particles of cross-linked poly (methyl methacrylate) (Sekisui Plastics Co., Ltd.)
The adhesive coating composition prepared by dispersing the above (manufactured) was applied and baked so that the film thickness became 15 μm to obtain a self-bonding insulated electric wire.

(Example 3) The same adhesive coating as in Example 2 except that the content of the above-mentioned true spherical particles was 1.0% by weight based on the resin content on the same polyesterimide wire as in Example 2. Was coated and baked so that the film thickness was 15 μm to obtain a self-fusing insulated electric wire.

(Example 4) An adhesive coating composition similar to that of Example 2 except that the content of the above-mentioned true spherical particles was 2.0% by weight based on the resin content on the same polyesterimide wire as in Example 2. Was coated and baked so that the film thickness was 15 μm to obtain a self-fusing insulated electric wire.

(Example 5) An adhesive coating composition similar to that of Example 2 except that the content of the above-mentioned true spherical particles was 4.0% by weight based on the resin content on the same polyesterimide wire as in Example 2. Was coated and baked so that the film thickness was 15 μm to obtain a self-fusing insulated electric wire.

Example 6 An adhesive coating composition similar to that of Example 2 except that the content of the above-mentioned true spherical particles was 10.0% by weight based on the resin content on the same polyesterimide wire as in Example 2. Was coated and baked so that the film thickness was 15 μm to obtain a self-fusing insulated electric wire.

Example 7 30 parts by weight of a phenoxy resin was dissolved in 60 parts by weight of cyclohexynone on the same polyesterimide wire as in Example 2, and 2.0 parts by weight of the resin component was added.
A self-fusing insulated electric wire was obtained by coating and baking an adhesive coating made by dispersing the above-mentioned true spherical particles having an average particle diameter of 4 μm in weight% so that the film thickness becomes 15 μm.

Example 8 On the same polyesterimide wire as in Example 2, 71.4 parts by weight of polyvinyl acetal resin, 28.6 parts by weight of phenoxy resin, and 50% by weight solution of alcohol-modified melamine-formaldehyde condensate 2
1.4 parts by weight and 71.7 parts by weight of furfural were dissolved in 2.0 parts by weight of the resin particles, and the above-mentioned fine spherical particles having an average particle size of 4 μm were dispersed in an adhesive coating having a film thickness of 15 μm. Coating and baking to obtain a self-bonding insulated electric wire.

(Comparative Example 1) The same adhesive coating as in Example 2 was applied on the same polyesterimide wire as in Example 2 except that the spherical fine particles were not included, and baked to a film thickness of 15 μm for self-fusion. It was made into an electrically insulated wire.

(Comparative Example 2) The same adhesive coating as in Example 7 was applied on the same polyesterimide wire as in Example 2 except that the spherical particles were not included, and baked to a film thickness of 15 μm for self-fusion. The insulated wire was used.

(Comparative Example 3) The same adhesive coating as in Example 8 was applied and baked to a film thickness of 15 μm on the same polyesterimide wire as in Example 2 except that the spherical particles were not included, and self-fusion was performed. It was made into an electrically insulated wire.

Comparative Example 4 A copper wire having a diameter of 0.5 mm was coated and baked with a commercially available polyesterimide coating so that the film thickness was 20 μm to obtain an insulated wire.

With respect to the insulated wires of these Examples and Comparative Examples, the flexibility, thermal softening temperature, reciprocating wear, adhesive force and life time at 240 ° C. were measured. The flexibility, heat softening temperature, and reciprocal wear were determined according to the same test rules as in Example 1, and the adhesive strength was 5 mm for the insulated wire.
A coil manufactured by winding 20 turns around a mm mandrel at 180 ° C. for 15 minutes is adhered to form a test piece, and the test piece is peeled off by pulling both ends at room temperature or 120 ° C. in an atmosphere. The peeling force was used.
Further, the life time at 240 ° C. is I.V. E. C Pub1
It measured based on 72. The results are shown separately in Table 2 and Table 3.

[0032]

[Table 2]

[0033]

[Table 3]

As can be seen from Tables 2 and 3, these self-fusing insulated electric wires exhibit the same adhesive strength as in the comparative example, and have extremely good wear resistance, and have a life time of 1000 at a high temperature such as 240 ° C. It has excellent performance such as being held for a long time.

[0035]

As described above, this insulated wire is
The outermost layer is provided with a lubricity coating layer obtained by applying and baking a coating composition in which spherical fine particles of crosslinked poly (methyl methacrylate) having an average particle size of 10 μm or less are added by 0.1 to 10% by weight with respect to the resin content of the coating composition Therefore, it has a low wear coefficient, is excellent in wear resistance, and is also excellent in heat resistance.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a first example of an insulated wire of the present invention.

FIG. 2 is a schematic cross-sectional view showing a modified example of the first example of the insulated wire of the present invention.

FIG. 3 is a schematic cross-sectional view showing a second example of the insulated wire of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conductor, 2 ... Sliding coating layer, 3 ... Insulating layer, 4 ... Sliding coating layer

Claims (3)

[Claims] 1. A slippery coating layer obtained by applying and baking a coating material in which true spherical fine particles of crosslinked polymethylmethacrylate having an average particle diameter of 10 μm or less are added in an amount of 0.1 to 10% by weight based on the resin content of the coating material. An insulated wire characterized by being provided in the outermost layer. 2. The insulated wire according to claim 1, wherein the slippery coating layer is an insulating layer. 3. The insulated wire according to claim 1, wherein the slippery coating layer is a self-fusing layer.