JPH11130993A - Insulating paint, insulated electric wire and electric instrument using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulated electric wire showing resistance to corona electric discharge, a long life, flexibility of an insulating coating film, good appearance, good winding and excellent abrasion resistance. SOLUTION: An insulating electric wire has an insulating layer obtained by coating insulating paint containing a particle of at least one of inorganic compounds selected from a silicon carbide, a silicon nitride, a molybdenum disulfide, an aluminum nitride, an aluminum silicate, a magnesium oxide, a zirconia, zirconia compounds, a nickel oxide, a trimanganese tetraoxide, a boron carbide, a boron nitride, a boron calcium, a titanium carbide, a titanium nitride, a forsterite, a steatite, a mullite, a ferrite and a cordierite and baking thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating paint for forming an insulating layer having excellent resistance to dielectric breakdown caused by corona discharge, an insulated wire using the insulating paint, and an insulated wire using the insulated wire. Related to electrical equipment.

[0002]

2. Description of the Related Art In recent years, there has been a tendency to increase the number of types of electrical equipment having a high applied voltage, and the corona discharge generated thereby corrodes an insulating film (corona destruction). There was a problem that the life of the insulated wire and eventually the electrical equipment was shortened due to destruction.

Therefore, conventionally, as a means for enhancing the resistance of an insulator to corona discharge, that is, the corona resistance and extending the life time until dielectric breakdown, a semiconductive layer is provided on the surface of an insulating film ( JP-A-2-18981
No. 4, Japanese Patent Application Laid-Open No. 57-2361, Japanese Patent Application Laid-Open No. 2-106812, and the like, in which particles such as alumina, silica, and chromium oxide are contained in an insulating film.

However, in the former means of providing a semiconductive layer, when compared to an insulated wire having the same coating thickness and no semiconductive layer, the thickness of the insulating layer is reduced even though the corona resistance is improved. However, there was a problem that the breakdown voltage was lowered. Also, the latter means of containing particles such as alumina, silica, and chromium oxide in the insulating film reduces the flexibility of the insulating film, and also causes deterioration in appearance and winding property due to roughness of the film surface. There was a problem.

[0005] In view of the above-mentioned circumstances, the present invention provides an insulated wire having high corona resistance, long life, excellent flexibility, appearance and winding property of an insulating film, and excellent wear resistance. ,
An object of the present invention is to provide an insulating paint used for forming an insulating layer of the insulated wire, and a long-life electrical device using the insulated wire.

[0006]

In order to achieve the above object, an insulating coating according to the first aspect of the present invention comprises silicon carbide, silicon nitride, molybdenum disulfide, aluminum nitride, aluminum silicate, magnesium oxide, zirconia, and zirconium. Including particles of at least one inorganic compound selected from compounds, nickel oxide, trimanganese tetroxide, boron carbide, boron nitride, calcium boride, titanium carbide, titanium nitride, forsterite, steatite, mullite, ferrite, cordierite It has a configuration.

[0007] Further, in the insulating paint according to claim 1,
In the invention of claim 2, the average particle diameter of the inorganic compound particles is 10 μm or less, and in the invention of claim 3, the inorganic compound particles have an average particle diameter of 5 to 50 parts by weight based on 100 parts by weight of the resin component in the paint. The composition contained in the range is adopted, and the invention of claim 4 adopts a composition in which the resin component of the paint is a thermosetting resin.

According to a fifth aspect of the present invention, there is provided an insulated wire, wherein the insulating film formed on the conductor includes an insulating layer formed by applying and baking the insulating paint according to any one of the first to fourth aspects. It consists of.

According to a sixth aspect of the present invention, in the insulated wire according to the fifth aspect, the insulating coating formed on the conductor is formed by applying and baking the insulating paint according to any one of the first to fourth aspects. And an insulating layer containing no particles. Also,
According to a seventh aspect of the present invention, in the insulated wire according to the fifth aspect,
The insulating film formed on the conductor is composed of three or more insulating layers, and the insulating layer formed by applying and baking the insulating paint according to any one of claims 1 to 4 constitutes an intermediate layer.

[0010] Further, the electric device according to the invention of claim 8 is characterized in that:
The insulated wire according to any one of claims 5 to 7 is used.

[0011]

DETAILED DESCRIPTION OF THE INVENTION As described above, the insulating coating of the present invention comprises silicon carbide, silicon nitride, molybdenum disulfide, aluminum nitride, aluminum silicate, magnesium oxide, zirconia, a zirconium compound, nickel oxide, and trimanganese tetroxide. , Boron carbide, boron nitride, calcium boride, titanium carbide, titanium nitride, forsterite, steatite, mullite, ferrite, and cordierite.

Thus, the insulated wire according to the present invention in which the insulating layer containing the inorganic compound particles obtained by applying and baking the insulating paint (hereinafter referred to as a particle-containing insulating layer) constitutes the whole or a part of the insulating film. Has a very long life due to the presence of the particle-containing insulating layer and thus has a high resistance to erosion and deterioration due to corona discharge, and has excellent wear resistance due to the high mechanical strength of the particle-containing insulating layer. Demonstrate. In addition, the corona resistance as described above is such that when a corona discharge occurs, the lines of electric force are dispersed over a wide area of the particle-containing insulating layer, so that the erosion due to the corona discharge does not concentrate on a local portion of the insulating film. It is presumed that the life of the insulating film as a whole until the dielectric breakdown caused by corona discharge is greatly extended as a whole.

The average particle size of the inorganic compound particles contained in the above-mentioned insulating coating is preferably 10 μm or less. If the particle size is too large, the appearance and flexibility of the insulating film of the insulated wire having the particle-containing insulating layer may be reduced. Is reduced. Further, the compounding amount of these inorganic compound particles depends on the resin component 10 in the insulating paint.
The range of 5 to 50 parts by weight relative to 0 parts by weight is preferable,
If the amount is too large, the appearance and flexibility of the insulating film of the insulated wire having the particle-containing insulating layer will be deteriorated. If the amount is too small, the corona resistance of the insulated wire will be insufficient.

As the resin component of the insulating paint, polyurethane, polyester, and the like are used in view of the heat resistance of the obtained insulating layer.
Polyester imide, polyamide imide, polyimide,
Thermosetting resins such as polyamide are suitable, and may be appropriately selected from these in accordance with the required properties such as heat resistance depending on the type of the insulated wire.

In order to prepare such an insulating coating, the above-mentioned inorganic compound particles are added to a solution of the above resin component, and the mixture is uniformly dispersed and mixed using a mixer such as a ball mill or a roll mill to which a shearing force is applied. Just do it. In addition, a coloring agent and other additives may be appropriately blended into the insulating paint together with the inorganic compound particles, if necessary. A commercially available insulating varnish can be used as the solution of the above resin component.

In the insulated wire of the present invention, the whole or a part of the insulating film formed on the conductor is constituted by a particle-containing insulating layer obtained by applying and baking the above-mentioned insulating paint.
The insulating film may have a single-layer structure composed of only the particle-containing insulating layer. However, the insulating film has two layers: a particle-containing insulating layer that forms one of the inner and outer layers, and an insulating layer that does not contain the particles that forms the other. It is recommended to have a structure and a multilayer structure of three or more layers using a particle-containing insulating layer for either the inner or outer layer or the intermediate layer. That is, if the multilayer structure of these two layers or three or more layers is used, good corona resistance can be imparted by the particle-containing insulating layer, and at the same time, various characteristics depending on the use of the insulated wire can be imparted by other insulating layers. .

In the above-mentioned insulating film having a multilayer structure of two or three or more layers, the outer layer (outermost layer in the case of multilayer) may be a particle-containing insulating layer. If the particle-containing insulating layer and the intermediate or inner layer in the case of a multilayer structure of three or more layers are used as the particle-containing insulating layer, the flexibility and appearance of the insulating film can be further improved, and the outer layer (in the case of a multilayer), There is an advantage that an insulated wire suitable for a specific use can be formed by using the outer layer) as a self-lubricating layer, a self-fusion layer, or the like. In particular, in the case of a multi-layer structure of three or more layers, if the intermediate layer is a particle-containing insulating layer, it is effective in terms of corona resistance. The thickness of the particle-containing insulating layer is not particularly limited, but when the insulating film has a multilayer structure of two layers or three or more layers, 10% of the total thickness of the insulating film is required to secure sufficient corona resistance. It is better to do the above.

The electric apparatus according to the present invention uses the above-described insulated wire according to the present invention. Since the insulated wire has excellent corona resistance, it is very good even when used under high voltage. It has the characteristic of exhibiting durability and having a long life. As such electric equipment, those used under a high voltage such as a high-voltage motor and a high-voltage transformer are typical, but not particularly limited.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the insulated wire according to the present invention will be specifically described below. In each of the examples, the polyester imide paint was trade name ISOM manufactured by Nippon Shokubai Co., Ltd.
ID 40SM (resin content: 45%) was also used as a polyamide-imide paint under the trade name HI-405 manufactured by Hitachi Chemical Co., Ltd.
(Resin content 34%) was used in each case. In the following, parts and% mean parts by weight and% by weight, respectively.

Examples 1 to 23 A polyesterimide paint was applied to the surface of a 1.0 mm-diameter soft copper wire and baked to form an insulation inner layer having a thickness of about 25 μm. Insulating paint prepared by blending the inorganic compound particles shown in Table 1 (all having an average particle diameter of about 1 μm) in 100 parts of the resin component of the paint in the number of parts shown in the same table is applied and baked to have a thickness of about 100 parts. A 5 μm insulating intermediate layer was formed, and a polyamideimide paint was applied and baked on the insulating intermediate layer to form an insulating outer layer having a thickness of about 5 μm. Thus, an insulated wire having an insulating coating having a three-layer structure was manufactured. .

Examples 24 to 46 Inorganic compound particles (each having an average particle diameter of about 1 μm) described in Table 2 below were applied to a polyesterimide paint on the surface of a soft copper wire having a diameter of 1.0 mm to 100 parts of the resin component of the paint. On the other hand, apply the insulating paint blended in the number of
After baking to form an insulating inner layer with a thickness of about 25 μm,
A polyamide-imide paint was applied and baked a plurality of times on the insulating inner layer to form an insulating outer layer having a thickness of about 10 μm, thereby producing an insulated wire having a two-layer insulating film.

Examples 47 to 69 Polyesterimide paint is applied and baked a plurality of times on the surface of a soft copper wire having a diameter of 1.0 mm to form an insulating inner layer having a thickness of about 30 μm. The coating is baked with an insulating coating prepared by mixing particles of the inorganic compound described in Table 3 below (each having an average particle diameter of about 1 μm) with 100 parts of the resin component of the coating, and coating and baking. An insulated outer layer having a thickness of about 5 μm was formed, and an insulated wire having an insulating film having a two-layer structure was manufactured.

Examples 70 to 72 For forming an insulating intermediate layer, silicon carbide particles were used in a polyesterimide paint. In Example 70, the average particle diameter was about 1 μm.
Insulating paint was used in which 30 parts of the resin composition of Example 71 had an average particle diameter of about 5 μm, and that of Example 72 had an average particle diameter of about 15 μm with respect to 100 parts of the resin component of the paint. Except for the above, an insulated wire having an insulating film having a three-layer structure was manufactured in the same manner as in Examples 1 to 4.

Examples 73 to 75 On the surface of an annealed copper wire having a diameter of 1.0 mm, aluminum silicate particles were applied to a polyesterimide paint. In Example 73, the average particle diameter was about 1 μm. In Example 74, the average particle diameter was about 5 μm.
μm, and in Example 75, an average particle diameter of about 12 μm, with respect to 100 parts of the resin component of the paint.
The insulating paint is mixed and coated several times with an insulating paint to form an insulating inner layer having a thickness of about 25 μm, and a polyesterimide paint is applied and baked on the insulating inner layer to form an insulating coating having a thickness of about 5 μm. An intermediate layer was formed, and a polyamideimide paint was applied and baked on the insulating intermediate layer to form an insulating outer layer having a thickness of about 5 μm. Thus, an insulated wire having an insulating film having a three-layer structure was manufactured.

Examples 76 to 78 For the purpose of forming an insulating outer layer, zirconium silicate particles were used in a polyamideimide paint.
μm, about 77 μm in Example 77, and about 15 μm in Example 78, using 30 parts of an insulating paint, each of which is mixed with 100 parts of the resin component of the paint. An insulated wire having a two-layer insulating film was manufactured in the same manner as in Example 52 except that the above procedure was repeated.

With respect to each of the insulated wires manufactured in the above-described examples, the items such as anti-pulse life, dielectric breakdown voltage, flexibility of insulating film, and appearance were examined. The results are shown in Table 1 for Examples 1 to 23, Table 2 for Examples 24 to 46, Table 3 for Examples 47 to 69, and Examples 70 to 70.
Table 4 shows 78. The pulse life was measured by applying a voltage of 2000 V and a frequency of 24000 Hz to a two-ply sample specified in JIS C 3003, and measuring the time until corona destruction. The dielectric breakdown voltage, the flexibility of the insulating film, and the appearance are all JI
It conformed to the test and evaluation method specified in SC 3003.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

From the results shown in Tables 1 to 3, it can be seen that the insulated wire according to the present invention is excellent in corona resistance, has a long life, and is excellent in dielectric breakdown voltage, flexibility of the insulating film, and appearance. In particular, when the particle-containing insulating layer forms an intermediate layer having a three-layer structure, the particle-containing insulating layer generally has better corona resistance than when the particle-containing insulating layer forms an outer layer and an inner layer in contact with a conductor. It is clear that the flexibility is superior to the case where the outer layer is formed. On the other hand, from the results in Table 4,
If the particles in the particle-containing insulating layer are too large, the flexibility and appearance will be inferior, and it is understood that those having an average particle diameter of preferably 10 μm or less should be used.

[0032]

According to the first aspect of the present invention, there is provided an insulating coating material which contains specific inorganic compound particles and can form an insulating layer having excellent corona resistance and a long life.

According to the second aspect of the present invention, there is provided, as the above-mentioned insulating coating, one in which an inorganic compound particle having a specific particle size can form an insulating layer having particularly excellent appearance.

According to the third aspect of the present invention, since the content of the inorganic compound particles is in a specific range, the insulating coating having sufficient corona resistance, good flexibility and appearance can be used as the insulating coating. What can be formed is provided.

According to the fourth aspect of the present invention, there is provided, as the above-mentioned insulating paint, one which can form an insulating layer having particularly excellent heat resistance because it contains a specific resin component.

According to the fifth aspect of the present invention, an insulated wire having an insulating layer containing the above-mentioned inorganic compound particles has excellent corona resistance and a long life.

According to the sixth aspect of the present invention, since the above-mentioned insulated wire having an insulating film composed of a plurality of insulating layers has the insulating layer containing the inorganic compound particles and the insulating layer not containing the particles. The present invention provides a material having excellent corona resistance and characteristics according to the intended use of the electric wire.

According to the seventh aspect of the present invention, in particular, in the above-mentioned insulated wire in which the insulating film has a multilayer structure of three or more layers, the intermediate layer of the insulating film is made of the insulating layer containing the inorganic compound particles. , While exhibiting excellent corona resistance,
An insulating film having good flexibility and appearance is provided.

According to the eighth aspect of the present invention, since the above-described insulated wires are used as various electric devices such as a high-voltage motor and a high-voltage transformer, those having excellent corona resistance and long life are provided. Is done.

Claims (8)

[Claims] 1. Silicon carbide, silicon nitride, molybdenum disulfide, aluminum nitride, aluminum silicate, magnesium oxide, zirconia, zirconium compound, nickel oxide, trimanganese tetroxide, boron carbide, boron nitride, calcium boride, titanium carbide, titanium carbide, An insulating paint containing particles of at least one inorganic compound selected from titanium nitride, forsterite, steatite, mullite, ferrite, and cordierite. 2. The inorganic compound particles having an average particle diameter of 10
The insulating paint according to claim 1, which has a thickness of not more than μm. 3. The insulating paint according to claim 1, wherein the inorganic compound particles are contained in an amount of 5 to 50 parts by weight based on 100 parts by weight of the resin component in the paint. 4. The insulating paint according to claim 1, wherein the resin component of the paint is a thermosetting resin. 5. An insulated wire, wherein the insulating film formed on the conductor includes an insulating layer obtained by applying and baking the insulating paint according to claim 1. 6. An insulating film formed on a conductor, comprising: an insulating layer formed by applying and baking the insulating paint according to claim 1; and an insulating layer containing no particles. The insulated wire according to claim 5, wherein the insulated wire is formed in layers. 7. An insulating film formed on a conductor comprises three or more insulating layers, and an insulating layer formed by applying and baking the insulating paint according to claim 1 constitutes an intermediate layer. The insulated wire according to claim 6. 8. An electric device using the insulated wire according to claim 5.