JP2577054Y2 - Heat resistant insulated wire - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant insulated wire in which an inorganic insulating layer is formed by applying and baking an inorganic polymer-based heat-resistant paint containing a polyborosiloxane resin and an inorganic filler on a conductor.

[0002]

2. Description of the Related Art Heat-resistant enameled wires, such as a polyimide wire, a polyamideimide wire, and a polyesterimide wire, are conventionally known as heat-resistant insulated wires.

However, since the insulating coating is made of an organic material, these materials are decomposed at a temperature of about 400.degree. C., and the highest usable temperature of the polyimide wire is at most about 240.degree.

[0004] An insulated wire in which a paint containing a silicone resin as a main component is applied to a conductor and baked is also known. However, the normal temperature is about 250 ° C. Peeling occurred and was unusable.

On the other hand, in the case of an insulated wire formed by applying a paint using a polyborosiloxane resin onto a conductor and baking it at a high temperature to form a coating, the coating peels off even at a temperature of 400 ° C. or more. It is noted because it can be used without it.

However, this insulated wire has a problem that the dielectric breakdown voltage is lower than an initial value when used at a high temperature because the coating film is generally porous.

[0007]

The insulated wire obtained by applying and baking a paint using a polyborosiloxane resin, which has been developed in recent years, on a conductor can be used even in a temperature environment of 400 ° C. or more. At a high temperature, there is a problem that the breakdown voltage becomes lower than the initial value.

The present invention has been made to solve such a conventional problem, and can be used in a temperature environment of 400 ° C. or more, and has an excellent initial breakdown voltage even when used at such a high temperature. It is an object of the present invention to provide a heat-resistant insulated wire capable of maintaining the temperature.

[0009]

According to the present invention, an inorganic insulating layer is provided on a conductor by applying and baking an inorganic polymer-based heat-resistant paint composed of a polyborosiloxane resin and an inorganic filler as components. In a heat-resistant insulated wire having an organic insulating layer provided by applying and baking an organic polymer-based heat-resistant paint, the inorganic insulating layer has a dispersed particle diameter of an inorganic filler.
The lower layer formed by coating and baking a paint having a particle size of 0.01 to 1.0 μm and having a content of 20 to 40 parts by weight, preferably 25 to 35 parts by weight per 100 parts by weight of the resin component, and a dispersed particle size of the inorganic filler of 5 to 5 parts by weight. 5050 μm and its content is 100
It is characterized in that it has a two-layer structure of 10 to 30 parts by weight, preferably 15 to 25 parts by weight, and an upper layer formed by coating and baking a paint.

That is, as shown in FIG. 1, the heat-resistant insulated wire according to the present invention basically has a polyborosiloxane resin as a first layer on a conductor 1 and 20 to 100 parts by weight of a resin component. 40 parts by weight, preferably 25 to 35 parts by weight of an inorganic filler and an organic solvent, the particle size of the inorganic filler is 0.01 to 1.0 μm
and a baking layer 2 of an inorganic polymer-based heat-resistant coating material (A) mixed and dispersed so as to have a thickness of m. The second layer is a polyborosiloxane resin and 10 parts by weight per 100 parts by weight of the resin component. To 30 parts by weight, preferably 15 to 25 parts by weight of an inorganic filler, and an organic solvent, the particle size of the inorganic filler is 5 to 50 μm.
m, a coating baking layer 3 of an inorganic polymer-based heat-resistant coating material (B) mixed and dispersed so as to obtain a m.
The third layer has a structure in which an application and baking layer 4 of an organic polymer heat-resistant paint (C) is sequentially provided.

The inorganic polymer-based heat-resistant coating material (A) constituting the first layer is composed of a polyborosiloxane resin and a particle size of 0.01.
It can be obtained by sufficiently stirring and mixing a particulate inorganic filler having a size of about 1.0 μm and an organic solvent with a media type disperser such as a sand mill or an attritor. With such stirring and mixing, the dispersed particle size of the particulate inorganic filler is 0.01 to 1.
0 μm.

[0012] The inorganic polymer heat-resistant paint (B) constituting the second layer is composed of a polyborosiloxane resin, a particulate inorganic filler having a particle size of 0.1 to 1.0 µm, and an organic solvent. It can be obtained by sufficiently stirring and mixing with a high-speed rotary dispersing machine such as a dissolver. By such stirring and mixing, the particulate inorganic filler is secondarily aggregated to have a dispersed particle diameter of 5 to 50 μm.

The polyborosiloxane resin used here is a resin having a main skeleton as shown below and having excellent heat resistance.

[0014]

Embedded image

The inorganic filler includes magnesium oxide, aluminum oxide, zirconium oxide, titanium oxide, chromium oxide, boron oxide, thorium oxide, silicon oxide, potassium titanate, mica, talc, and the like having the above-mentioned particle size.
Silicon carbide, titanium carbide, zirconium carbide, titanium nitride, aluminum nitride, or the like can be used.
These may be used alone or as a mixture of two or more. Further, organic solvents include xylene, toluene, benzene, ethanol, and butanol.
, Cellosolves, ketones, N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, phenols and the like can be used. Silicone oil can also be used as a reaction solvent for the polyborosiloxane resin.

Each of these paints (A) and (B) has:
In addition to the above components, a silicone resin and other additives may be added within the range not impairing the effects of the present invention for the purpose of improving the flexibility and hydrolysis resistance of the coating film and improving the adhesion to the conductor. Can be blended.

As the silicone resin, in addition to pure silicone, silicone alkyd, silicone polyester,
Silicone acrylic, silicone epoxy, silicone urethane and the like can also be used. Commercially available products are exemplified by, for example, TSR116, TSR117, TSR made by Toshiba Silicone Co., Ltd.
R 127B, TSR144, SH 804, SH 80 manufactured by Toray Silicone
5, SH806A, SH808, SH840 (all are trade names). The amount of the silicone resin is preferably 50% by weight or less in the resin.

In the coating material (A), the amount of the inorganic filler is limited to the range of 20 to 40 parts by weight per 100 parts by weight of the resin. This may cause floating or peeling of the conductor, and conversely, if it is more than this, the adhesion to the conductor becomes poor, and the hardness also decreases.

The reason why the amount of the inorganic filler in the paint (B) is limited to the range of 10 to 30 parts by weight per 100 parts by weight of the resin component is the same as in the case of the paint (A). If used at a high temperature, the coating film may be lifted or peeled off. On the contrary, even if the amount is large, the adhesion to the lower layer becomes poor and the hardness is lowered.

Each of these paints (A) and (B) is baked at a temperature of 500 to 600 ° C. after application, whereby the organic components are decomposed into ceramics. A coating film excellent in heat resistance without causing peeling or peeling is formed. In particular, the coating film of the paint (A) is very dense and has excellent dielectric breakdown characteristics at high temperatures. on the other hand,
The coating film formed by the paint (B) is slightly rough, and the paint (A)
Although it does not have the dielectric breakdown characteristics at high temperatures as high as that of the coating film of (a), by providing such a coating film on the coating film of the paint (A), an organic polymer-based heat resistance as described below provided further thereon The coating (C) has an effect of preventing cracks due to thermal decomposition at a high temperature of the coating and baking layer from affecting the coating film of the coating (A).

The organic polymer heat-resistant paint (C) constituting the third layer includes polyester, polyesterimide,
A paint in which an organic polymer having excellent heat resistance such as polyimide, polyamide imide, polyamide, polyimidazopyrololone, formal, polyurethane, epoxy or the like can be used alone or as a mixture can be used. Such a coating and baking layer of the paint (C) has an effect of reinforcing mechanical properties such as elongation of the coating and baking layers of the lower coatings (A) and (B).

The heat-resistant insulated wire of the present invention is obtained by applying and baking each of the above-mentioned paints (A), (B) and (C) on a conductor in a conventional manner, and baking each paint. The thickness of the layers is, in order, 10-40 μm, 1-15 μm, 1-8
The range of μm is appropriate.

As the conductor of the present invention, a Ni wire, an Ag wire, a Ni-plated or Ag-plated copper wire having good heat resistance and the like are preferably used.

[0024]

The heat-resistant insulated wire according to the present invention is provided with a baking layer of an inorganic polymer-based heat-resistant paint which is very dense and has good dielectric breakdown characteristics at high temperatures as a first layer on the conductor. As a second layer, a coating baking layer of an inorganic polymer-based heat-resistant paint, which is slightly coarser than the first coating baking layer, is provided;
Further, a third layer is provided with a coating and baking layer of an organic polymer heat-resistant paint as a third layer, so that the characteristics of the first baking layer are different from those of the second and third layers. As a result of being protected and reinforced by the coated and baked layer, it can be used at a high temperature of 400 ° C. or more, and has excellent heat resistance without a significant decrease in dielectric breakdown characteristics even at a high temperature.

[0025]

Next, examples and comparative examples will be described.

Examples 1-4, Comparative Examples 1-5 Polyborosiloxane resin solution (50% solution of polyborosiloxane resin in N-methyl-2-pyrrolidone), Toshiba Silicone
TSR116 (trade name of 50% xylene solution of phenyl methyl silicone resin manufactured by Toshiba Silicone Co., Ltd.), average particle size 0.2μ
m magnesium oxide, aluminum oxide, zirconium oxide, magnesium oxide having an average particle size of 0.02 μm, and N-methyl-2-pyrrolidone (NMP) as shown in Table 1. Under various conditions to prepare various paints.

Next, the obtained paint and a polyester resin varnish (abbreviated as PES) were combined as shown in Tables 2 and 3 to form a 1.0 mm φ Ni plated copper wire (plated thickness).
1.5 μm), using a vertical baking machine with a furnace length of 7 m, applying baking at 450 ° C. and a linear speed of 6 m / min until the desired film thickness is obtained. Insulated wire was obtained.

Tables 2 and 3 show the characteristics of the obtained insulated wires.
Are shown together.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

[Table 3]

[0032]

As is clear from the above embodiments, the heat-resistant insulated wire according to the present invention is an inorganic polymer based on a very dense layer as a first layer on a conductor and has good dielectric breakdown characteristics at high temperatures. An application baking layer of a heat-resistant paint is provided. On top of this, an application baking layer of an inorganic polymer-based heat-resistant paint, which is slightly rougher than the first layer, is further provided. Since it has a structure in which a paint coating layer is provided, it can be used at high temperatures of 400 ° C or more, and has excellent dielectric breakdown characteristics at high temperatures.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the basic structure of the heat-resistant insulated wire of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Conductor 2 ... Baking layer of inorganic polymer-based heat-resistant paint (A) 3 ... Baking layer of inorganic polymer-based heat-resistant paint (B) 4 ... Organic polymer-based heat-resistant paint ( C) Coating baking layer

Claims (1)

(57) [Scope of request for utility model registration] An inorganic insulating layer is provided on a conductor by applying and baking an inorganic polymer-based heat-resistant paint composed of a polyborosiloxane resin and an inorganic filler, and an organic polymer-based heat-resistant paint is further provided on the outer periphery thereof. In a heat-resistant insulated wire having an organic insulating layer provided by coating and baking, the inorganic insulating layer has a dispersed particle diameter of an inorganic filler of 0.01 to 1.
A lower layer formed by coating and baking a paint having a thickness of 0 μm and a content of 20 to 40 parts by weight per 100 parts by weight of the resin component,
The inorganic filler has a two-layer structure with a dispersed particle size of 5 to 50 μm and a content of 10 to 30 parts by weight per 100 parts by weight of the resin component by coating and baking a paint. Heat resistant insulated wire.