JPH0679450B2 - Sliding insulated wire - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a slippery insulated wire in which the insulating coating itself has very good slipperiness and is less likely to cause defects or breakage of the insulating coating even at high speed winding. .

(Problems of the prior art) In recent years, in the manufacture and processing of insulated wires, the winding speed and space factor, that is, the amount of wires to be arranged in a certain space, are set in order to speed up the whole process and improve space efficiency. Tends to increase. However, with such a tendency, the load applied to the insulated wire is inevitably increased, and the defect due to the damage of the insulating coating and the disconnection are likely to occur.

In order to reduce the above load, it is effective to increase the slipperiness of the surface of the insulated wire to reduce the friction resistance,
Initially, a method of applying a lubricating component such as lubricating oil, paraffins or wax to the surface of the insulating coating, or a method of providing an overcoat layer made of a resin having a low coefficient of friction such as nylon or polyethylene (Japanese Patent Publication No. 47-33712). Although the method of blending the above-mentioned lubricating component into the insulating coating has been adopted, these methods can no longer cope with the severe winding conditions in recent years.

Therefore, as an alternative to the above method, a low molecular weight polyethylene having an average molecular weight of 6,500 or less may be blended in a specific amount as a solution or a fine particle dispersion in an insulating coating material forming an insulating coating (Japanese Patent Publication Nos. 51-28420, 53). -9392, JP-A-5
No. 6-86410, No. 57-158726, No. 63-119109,
No. 63-121214, etc.), and polypropylene powder, which is fine particles having an average particle diameter of 10 μm or less, and polyethylene powder or tetrafluoroethylene powder, are blended in a specific amount (Japanese Patent Publication No. 63-63)
-59482, 63-59483, etc.) have been proposed.

(Problems to be solved by the invention) However, in each of the above proposed means, reduction of the friction coefficient of the insulating coating and improvement of wear resistance are achieved by blending a resin component having a low friction coefficient such as fine particles, The results are better than those of using the above-mentioned lubrication component or forming the overcoat layer, but it is not enough to cope with the severe winding conditions in recent years, and there is room for improvement especially in terms of wear resistance. However, in order to obtain abrasion resistance above a certain level, it is necessary to use a special base insulating coating that mixes the resin components or use a special additive in combination to increase the insulation coating thickness. Therefore, there is a fatal drawback as a general-purpose insulated wire in that the material cost is high.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a slippery insulated wire that can sufficiently cope with recent increases in winding speed and space factor and can be manufactured at low cost.

(Means for Solving the Problems) The inventors of the present invention have conducted extensive studies in order to achieve the above-mentioned object, and as a result, have found that the abrasion resistance of an insulating coating formed from a paint obtained by blending polyethylene fine powder alone into an insulating paint. Is greatly influenced by the average molecular weight of the polyethylene. Contrary to the proposed method, according to the high molecular weight polyethylene having an average molecular weight of 8,000 or more, when the average particle diameter and the blending amount are within a specific range, the blending is performed. It has been clarified that even if the insulation coating made of the above-mentioned paint has a thin coating thickness of about one-time coating, it will be possible to obtain extremely high abrasion resistance, which has not been achieved in the past, and which has a low friction coefficient and a good appearance. Then, the invention was completed.

That is, the insulated wire according to the present invention has a plurality of insulating coatings formed on the conductor, and the uppermost layer has an average molecular weight of 8,00.
Fine powder composed of 0 or more polyethylene and having an average particle size of 10μ or less is mixed in an insulating paint at a ratio of 0.1 to 10% by weight with respect to the binder component, and a film thickness of 12μm or less formed by baking the paint. It is characterized by comprising layers.

(Detailed configuration and function of the invention) In the lubrication insulated electric wire of the present invention, the largest factor that influences the abrasion resistance and lubricity of the insulation coating is the polyethylene compounded in the insulation coating for forming the top insulation coating. It is the average molecular weight of the fine powder. That is, the fine powder is a high molecular weight polymer having an average molecular weight of 8,000 or more, and the presence of such a high molecular weight polyethylene in the form of particles in the uppermost layer of the insulating layer shows the performance test results of Examples described later. As described above, even when the uppermost layer has a thin film thickness of about one coating, the number of reciprocating abrasions is 170 times or more, and in the preferred embodiment, 200 times or more.
It has extremely high wear resistance such as more than one turn and good lubricity of about 0.07 in coefficient of static friction (μs), which makes it possible to prevent defects and disconnection due to damage to the insulation coating even under recent severe high-speed winding conditions. It is possible to prevent it completely. When the above-mentioned average molecular weight is less than 8,000, wear resistance and lubricity are remarkably reduced.

On the other hand, for this type of insulated wire, if the appearance deteriorates, the commercial value is lost, but this appearance is greatly affected by the average particle size and the blending amount, especially when blending the high-molecular-weight polyethylene fine powder as described above. To be done. That is, when the above-mentioned average particle diameter is larger than 10 μm and when the content of the fine powder is more than 10% by weight with respect to the binder component of the insulating coating, the appearance of the electric wire is poor and the insulated electric wire Cannot be used as. The above blending amount is 0.1
If the amount is less than 10% by weight, the effect of using the polyethylene fine powder is not sufficiently exerted, and both the wear resistance and the lubricity are reduced, which is not preferable.

The insulating coating material containing such polyethylene fine powder is not particularly limited, and various insulating coating materials known for forming an insulating coating film of general insulated electric wires and self-fusing insulated electric wires, such as polyvinyl formal type and polyurethane type Insulating paints such as polyester, polyamide, polyesterimide, polyamideimide, and polyimide can be used. Further, the means for blending polyethylene fine powder in these insulating paints is not a method of directly adding and mixing the powder from the viewpoint of dispersibility, but the fine powder is dispersed in a solvent such as toluene, xylene, cyclohexanone, or naphtha. A method of adding and mixing in the form of a dispersion is suitable.

Therefore, in the slip insulated wire of the present invention, the insulating coating film may have a plurality of layers, and only the uppermost layer thereof may be a layer having a film thickness of 12 μm or less, which is formed by the insulating coating material containing the above-mentioned polyethylene fine powder. That is, in the constitution of the present invention, the above-mentioned effects of improving wear resistance and lubricity are carried by the surface layer portion of the insulating coating, and the coating thickness of the layer formed of the insulating coating material containing polyethylene fine powder is not less than a certain level. Even if it becomes thicker, it is not possible to expect any further increase in the above improvement effect, and the film thickness is 12 μm.
It is admitted that it will decrease if it exceeds m. Therefore, the necessary thickness as the original insulating coating may be ensured by the thickness of the lower layer formed by a normal insulating coating material containing no polyethylene fine powder.

It should be noted that the coating thickness of the uppermost layer of 12 μm or less means that the uppermost layer can be formed by one coating or two coatings by the usual coating and baking means. This has the advantage of reducing the time and effort required to adjust the coating material, and reducing the amount of polyethylene fine powder used, thus reducing material costs.

The insulating coating material for the lower layer containing no polyethylene fine powder may be the same as or different from the insulating coating material as the base of the coating material for the uppermost layer. Further, the lower layer itself may have a laminated structure of two or more layers formed of different kinds of insulating paint.

The formation of such a plurality of layers of insulating film may be carried out according to a conventional method, and the step of applying and baking the continuously running conductor through a paint tank and a heating furnace in which the conductor is adjusted to the required composition is repeated a required number of times. Good.

(Example) Hereinafter, the present invention will be specifically described with reference to Examples.

Examples 1 to 6 A polyester imide insulating coating (Isomid 40H manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.) was applied and baked on the surface of a 1.0 mm diameter copper wire according to a conventional method at the number of times shown in Table 1 below to form a lower layer. ,
Next, polyamide-imide insulating paint (made by Hitachi Chemical Co., Ltd.
HI405 H) with a toluene dispersion of polyethylene fine powder shown in the same table in the proportion shown in the same table, and apply it in the usual manner, apply and bake at the number of times given in the same table to form the upper layer. A smooth insulated electric wire with a finished outer diameter of 1.074 mm was produced.

Example 7 A smooth insulated electric wire having a finished outer diameter of 1.078 mm was produced in the same manner as in Examples 1 to 6 except that the insulating coatings used for forming the upper and lower layers were both polyesterimide insulating coatings (Isomid 40H ... .

Comparative Examples 1 and 2 Insulated electric wires were produced in the same manner as in Examples 1 to 6 except that fine polyethylene powder was not mixed in the lower layer insulating coating material. The number of times of coating and baking of the upper and lower layers is as shown in Table 2 below.

Comparative Examples 3 to 7 Insulated electric wires were prepared in the same manner as in Examples 1 to 6 except that polyethylene fine powder to be blended in the lower layer insulating paint, its blending amount, and the number of times the upper and lower layers were coated are shown in Table 2 below. Was produced.

Comparative Example 8 A copper wire having a diameter of 1.0 mm was coated and baked with a polyesterimide insulating coating (Isomid 40H) eight times according to a conventional method to produce an insulated electric wire having a single-layer insulating coating.

For each insulated wire of the above examples and comparative examples, the film thicknesses of the upper and lower layers of the insulating coating were measured, and as a performance test, the quality of appearance, static friction coefficient (μs), and reciprocating wear based on JIS C 3003-1976. (Times) was measured. The results are shown in Table 1 for the examples and in Table 2 for the comparative examples. The number of coatings of the upper and lower layers (one coating / baking is performed) and the average particle diameter (μ) of the polyethylene fine powder blended in the lower layers are shown.
m), the average molecular weight, and the blending amount with respect to the binder component of the insulating coating for the lower layer. For the insulated wire judged to have a poor appearance, the static friction coefficient and reciprocating wear were not measured.

From the results of Tables 1 and 2, the insulated electric wires according to the present invention all have a good appearance, and the upper layer has excellent abrasion resistance and excellent wear resistance in a thin coating thickness obtained by applying or baking once or twice. It is clear that it exhibits lubricity. On the other hand, in the case of an insulated wire with a conventional structure in which polyethylene fine powder is not mixed in the upper layer, in order to obtain a certain level of abrasion resistance and abrasion resistance, use a high abrasion resistance insulating paint such as polyamide-imide. It turns out that it is necessary to thicken the upper layer. Further, if the average particle diameter of the polyethylene fine powder is too large or the blending amount is too large, the appearance becomes poor. If the polyethylene of the fine powder has a low average molecular weight or a too small blending amount, abrasion resistance and It can also be seen that the lubricity becomes insufficient. The insulated wire of Comparative Example 7 in which only the thickness of the lower layer was thicker than the specified range was relatively good in both abrasion resistance and lubricity, but the thickness of the lower layer was smaller than that in the example.
Inferior to 1,6 insulated wire.

(Effects of the Invention) As described above, since the slippery insulated electric wire of the present invention has extremely excellent wear resistance and good slipperiness, damage to the insulating coating is caused even by high-speed winding. Forming the top layer of the insulation film that is less likely to cause defects and disconnections and can sufficiently meet the recent demands for speeding up the entire process in manufacturing and processing and improving space effects, has a good appearance, and is responsible for lubricity. It does not require a special binder combination or special additives as the insulating paint, and can use the insulating paint of the usual composition used for general insulated wires and self-fusing insulated wires, which is inexpensive. Can be manufactured.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Oyano 2-19-1 Inadera, Amagasaki-shi, Hyogo Daiichi Denko Co., Ltd. Winding Division Technical Department (56) Reference JP-A-49-41868 A) JP-A-49-117984 (JP, A) JP-A-56-86410 (JP, A) JP-A-63-119109 (JP, A) JP-A-63-121214 (JP, A) Actual development Sho-57 -158726 (JP, U) Actual 63-182407 (JP, U) JP 47-33712 (JP, B1) JP 51-28420 (JP, B2) JP 53-9392 (JP, B2) ) JP-B-63-59482 (JP, B2) JP-B-63-59483 (JP, B2)

Claims (1)

[Claims] 1. A plurality of insulating coatings are formed on a conductor, and the uppermost layer is a fine powder made of polyethylene having an average molecular weight of 8,000 or more and having an average particle size of 10 μm or less in an insulating coating material for the binder component. A smooth insulated electric wire comprising a layer having a coating thickness of 12 μm or less, which is formed by baking a paint compounded in a proportion of 0.1 to 10% by weight.