JPH02199710A - Insulation cable with slippery property - Google Patents

Abstract

PURPOSE:To improve both wear resistance and slippery property by constituting the uppermost layer of a plurality of layers on a conductor with a layer 12mum thick or less formed by baking a specific coating. CONSTITUTION:A plurality of insulation layers are formed on a conductor. In this case, the uppermost layer is formed 12mum thick or less with baked paint made by mixing fine powder of mean particle diameter of 10mum or less of polyethylene of mean molecular weight of 8000 or more into insulation paint with the ratio 0.1-10weight% in relation to the binder of the coating. This results in excellent wear resistance and slippery property. As a result, less rejects due to damages in the insulation layers and cable breakages caused even with high speed wire winding.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is characterized by the fact that the insulating coating itself has very good lubricity so that even high-speed winding will not cause defects or disconnections in the insulating coating (non-slippery insulation). Regarding electric wires.

(Issues of the prior art) In recent years, in the manufacturing and processing of insulated wires, the winding speed and space factor, that is, the amount of wire arranged in a certain space, have been increased in order to speed up the entire process and improve space efficiency. It tends to get bigger. However, as a result of this trend, the load applied to the insulated wire inevitably increases, making it more likely to cause defects or even disconnections due to damage to the insulating coating.

In order to reduce the above load, it is effective to increase the slipperiness of the surface of the insulated wire and reduce the frictional resistance.
Initially, there were two methods: applying a lubricating component such as lubricating oil, paraffin, or wax to the surface of the insulating coating, providing a top coat layer made of a resin with a low coefficient of friction such as nylon or polyethylene, and applying the above lubricating component to the insulating coating. However, these methods are no longer able to cope with the harsh winding conditions of recent years.

Therefore, as an alternative to the above-mentioned method, the average molecular weight s, oo is added to the insulating paint for forming the insulating coating.

The following low molecular weight polyethylenes may be blended in a specific amount as a solution or fine particle dispersion (Japanese Patent Publications No. 51-28420, No. 53-9392, etc.), each with an average particle diameter of 10 μm.
A specific amount of polypropylene powder and polyethylene powder or tetrafluoroethylene powder, which are fine particles of m or less, are blended (
Special Publication No. 63-59482, No. 63-59483, etc.)
It is proposed that.

(Problem B to be solved by the invention) However, in each of the above proposed means, the friction coefficient of the insulating film is reduced and the wear resistance is improved by blending a resin component with a low friction coefficient in the form of fine particles. Although better results can be obtained than the above-mentioned means of using lubricating components or forming an overcoat layer, it is still not sufficient to meet the severe winding conditions of recent years, and there is no improvement in wear resistance in particular. In order to obtain a certain level of abrasion resistance, it is necessary to use a special insulating paint as the base in which the resin components are blended, or to increase the thickness of the insulating coating, which reduces material costs. The problem was that it was expensive.

In view of the above-mentioned circumstances, 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) As a result of extensive studies to achieve the above object, the present inventor has found that the wear resistance of an insulating coating formed from a paint containing polyethylene fine powder alone in an insulating paint. is largely influenced by the average molecular weight of the polyethylene, and contrary to the proposed method, when using high molecular weight polyethylene with an average molecular weight of s, ooo or more, when the average particle diameter and blending amount are set within a specific range, this It was discovered that even if the insulating coating made of a paint containing the following is as thin as one coat, it is possible to obtain an extremely high abrasion resistance that has not been achieved before, and to produce an insulated wire with a low coefficient of friction and a good appearance. This led to the completion of this invention.

That is, in the insulated wire according to the present invention, a plurality of upper and lower insulation coating layers are formed on a conductor, and the uppermost layer is made of polyethylene with an average particle diameter of 10 and an average molecular weight of 8.000 or more.
It is characterized by being composed of a layer with a thickness of 12 μm or less formed by baking a paint containing fine powder of 0.1 to 10% relative to the binder component in an insulating paint. It is something to do.

(Detailed structure and operation of the invention) In the slippery insulated wire of the present invention, the biggest factor that influences the wear resistance and slipperiness of the insulation coating is the polyethylene that is blended into the insulation paint for forming the top layer insulation coating. This is the average molecular weight of fine powder. That is, the fine powder has an average molecular weight t a,o
By using a high molecular weight polymer with a molecular weight of 0.0 or more, as shown in the performance test results in the examples described later, even if the top layer is as thin as one coat, it can be worn 170 times by reciprocating abrasion. As mentioned above, the preferred embodiment has extremely high wear resistance of 200 times or more, and a static friction coefficient (μs) of 0.
．． Good lubricity of around 0.07 can be obtained, which makes it possible to almost completely prevent defects and disconnections due to damage to the insulation coating even under the severe high-speed winding conditions of recent years. Incidentally, when the above average molecular weight is smaller than 8.000, the wear resistance and lubricity are significantly reduced.

On the other hand, this type of insulated wire loses its commercial value if its appearance deteriorates, and this appearance is greatly influenced by the average particle size and blending amount of the fine polyethylene powder. That is, if the above average particle diameter is larger than 10 μI, and if the blending amount of the fine particles is more than 10% by weight based on the binder component of the insulating paint, the appearance of the wire will be poor and the insulated wire will not be suitable. can no longer be used as In addition, if the above-mentioned amount is less than 0.1% by weight, the effect of using the fine polyethylene powder will not be fully exhibited, and both the above-mentioned wear resistance and lubricity will decrease, which is not preferable.

Insulating paints containing such polyethylene fine powder are not particularly limited, and include various insulating paints known for forming insulation coatings on boat-type insulated wires and self-bonding insulated wires, such as polyvinyl formal-based and polyurethane-based insulating paints. Insulating paints such as polyester, polyester, polyamide, polyesterimide, polyamideimide, and polyimide can be used. In addition, from the viewpoint of dispersibility, the method for blending polyethylene fine powder into these insulating paints is not to directly add and mix the powder, but to disperse the fine powder in a solvent such as toluene, xylene, cyclohexanone, or naphtha. A method of adding and mixing in the form of a dispersion liquid is suitable.

Therefore, the slippery insulated wire of the present invention has two upper and lower insulation coating layers, and only the uppermost layer is formed with an insulation paint containing the above-mentioned polyethylene fine powder, and has a coating thickness of 12 μm.
In other words, in the structure of the present invention, the above-mentioned effect of improving wear resistance and slipperiness is carried out in the surface layer of the insulating coating, and the insulating coating containing fine polyethylene powder is used as the layer. It has been recognized that even if the mi of the formed layer becomes thicker than a certain level, the above-mentioned improvement effect cannot be expected to increase any further, and that if the film thickness exceeds 12 .mu.m, it actually decreases. Therefore, the thickness required for the original insulating coating can be ensured by the thickness of the lower layer formed from a normal insulating paint that does not contain fine polyethylene powder.

In addition, the film thickness of the top layer is 12 μm or less,
Conventional coating and baking means that depending on the method, the top layer can be formed in one or two coats, which reduces the effort of adjusting the paint by blending fine powder, and
This also has the advantage of reducing the amount of polyethylene fine powder used, which reduces material costs.

In addition, tIA for the lower layer that does not contain polyethylene fine powder
The edge paint may be of the same type as the insulating paint that is the base of the uppermost layer paint, or may be of a different type. Further, the lower layer itself may have a laminated structure of two or more layers formed of different types of insulating paints.

Formation of such a multi-layered insulating film can be carried out according to a conventional method, by repeating the process of passing a continuously running conductor through a paint bath adjusted to the desired composition and a heating furnace, coating and baking it as many times as necessary. Bye.

(Example) The present invention will be specifically explained below using examples.

Examples 1 to 6 Polyesterimide insulating paint (l5ostd40H manufactured by Nippon Shokubai Chemical Co., Ltd.) was applied to the surface of the trunk line of 1.0 ma + diameter.
A lower layer was formed by coating and baking according to a conventional method the number of times shown in Table 1 below, and then a toluene dispersion of polyethylene fine powder shown in the same table was applied to a polyamide-imide insulation paint (1114058 manufactured by Hitachi Chemical Co., Ltd.). Apply the paint in the usual manner using a paint compounded in the proportions listed in the same table, and apply it the number of times listed in the table.
An upper layer was formed by baking to produce a slippery insulated wire with a finished outer diameter of 1.074a*.

Example 7 The finished outer diameter was 1°078 in the same manner as Examples 1 to 6, except that the insulating paint used to form the upper and lower layers was polyesterimide insulating paint (Iso 1d40H...described above).
A fake slippery insulated wire was created.

Comparative Examples 1 and 2 Insulated wires were produced in the same manner as Examples 1 to 6, except that polyethylene fine powder was not blended into the insulating paint for the lower layer. The number of times the upper and lower layers were coated and baked is as shown in Table 2 below.

Comparative Examples 3 to 7 Insulated wires were prepared in the same manner as Examples 1 to 6, except that the fine polyethylene powder mixed in the insulation paint for the lower layer, the amount thereof, and the number of coatings for the upper and lower layers were as shown in Table 2 below. was created.

Comparative Example: An insulated wire having a single layer of insulation coating was prepared by applying and baking a polyesterimide insulating paint (fsomi 640H) eight times on the surface of a 1.0 M diameter trunk wire according to a conventional method.

For each insulated wire of the above Examples and Comparative Examples, the thickness of the upper and lower layers of the insulation coating was measured, and performance tests were conducted to determine whether the appearance was good or not, the coefficient of static friction (μs), and JISC3003-
Reciprocating wear (times) was measured based on 1976. The results are shown in Table 1 for Examples and Table 2 for Comparative Examples.
In addition, the number of coatings for the upper and lower layers (coating and baking are counted as one time), the average particle diameter (μal) and average molecular weight of the polyethylene fine powder blended in the lower layer, and the amount of the insulating paint for the lower layer relative to the binder component. show. In addition, the appearance was determined to be defective! ! For electric wires, measurements of static friction coefficient and reciprocating wear were omitted.

From the results in Table 1.2, the insulated wires according to the present invention all have a good appearance, and the upper layer has extremely excellent wear resistance and good lubricity even with a thin film thickness coated and baked once or twice. It is clear that it indicates gender. In contrast,
Insulated wires with a conventional structure that does not contain fine polyethylene powder in the upper layer have very low slipperiness, and in order to obtain a certain degree of abrasion resistance, the upper layer must be thickened with a highly abrasion-resistant insulating paint such as polyamide-imide. It turns out that it is necessary.

In addition, if the average particle size of the polyethylene fine powder is too large or the amount blended is too large, the appearance will be poor, and if the average molecular weight of the polyethylene in the fine powder is low or the amount blended is too small, the wear resistance and It can also be seen that the lubricity is insufficient. In addition, in Comparative Example 7, only the thickness of the lower layer is thicker than the specified range.
Although the insulated wire has relatively good wear resistance and slipperiness, it is inferior to the insulated wire of Example 1.6 in which the underlying layer is thinner.

(Effects of the Invention) As described above, since the slippery insulated wire of the present invention has extremely excellent wear resistance and good slipperiness, it is possible to avoid damage to the insulation coating even when winding at high speed. It is less likely to cause defects or disconnections, and can fully meet recent demands for speeding up the overall process and improving space efficiency in manufacturing and processing.

Claims (1)

[Claims] Multiple layers of insulation coating are formed on the conductor, and this top layer is
Formed by baking a paint containing a fine powder of polyethine with an average molecular weight of 8,000 or more and an average particle size of 10 μm or less mixed in an insulating paint at a ratio of 0.1 to 10% by weight based on the binder component. A slippery insulated wire characterized by comprising a layer having a coating thickness of 12 μm or less.