JPH11297124A - Heat resistant self melt-bonding enameled wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To melt-bond at a low temperature and hold high adhesion after bonding even at a high temperature by forming a melt-bonding layer comprising the specific sulfone group-containing polyhydroxypolyether resin and an aromatic acid anhydride on a conductor directly or through another insulating material. SOLUTION: A melt-bonding layer is formed on an enameled wire manufactured by forming a polyesterimide layer on a conductive wire to obtain a self melt-bonding enameled wire. The melt-bonding layer is formed by applying a solution prepared by dissolving sulfone group-containing polyhydroxypolyether resin represented by the formula and an aromatic acid anhydride in a cyclohexane or the like, and baking. The content of the sulfone group in the molecular skeleton of the sulfone group-containing polyhydroxypolyether resin is preferable to be 30-50%. As the aromatic acid anhydride, trimellitic acid anhydride having one acid anhydride and one carboxyl group is preferable. The mixing of 2-50 pts.wt. aromatic anhydride to the 100 pts.wt. resin is preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant self-fusing enameled wire.

[0002]

2. Description of the Related Art A self-fusing enameled wire is obtained by coating and baking a fusion layer on the outer periphery of a general enameled wire.

The self-fusing enameled wire is widely used as a magnet wire for a deflection yoke coil of a television or a display, since the outer fusion layer easily exhibits a fusion property by heat treatment or organic solvent immersion treatment. Have been.

In recent years, this self-fusing enameled wire has been frequently used as a magnet wire for these electric coils in response to demands such as elimination of varnish treatment for fan motors, clutch motors, electric component coils, and shortening of the manufacturing process. It is becoming.

[0005] However, it is known that fan motors, clutch motors, electric component coils and the like are subjected to severe operation, and as a result, the operating temperature of those electric coils rises.

For this reason, a self-fusing enameled wire used as a magnet wire for an electric coil such as a fan motor, a clutch motor, or an electric component coil is required to have excellent adhesive strength even at a high temperature.

[0007] The following materials have been used as conventional fusion materials for self-fusing enameled wires.

(1) Polyvinyl butyral resin (2) Copolyamide resin (3) Phenoxy resin

[0009]

However, the polyvinyl butyral resin of the above (1) has the lowest heat resistance among these, and therefore cannot be used as a fusion material for heat-resistant self-fusing enameled wires.

[0010] The copolymerized polyamide resin of the above (2) has better heat resistance than polyvinyl butyral resin, but is disadvantageous in that the adhesive strength at high temperatures is low.

The phenoxy resin (3) is superior in heat resistance to the copolyamide resin, but has a disadvantage that the adhesive strength at a higher temperature is low.

Therefore, the present inventors have previously proposed a heat-resistant self-fusing enameled wire to which a polysulfone group-containing polyhydroxypolyether resin is applied as a fusing material. The adhesive force at high temperature of the heat-resistant self-fusing enameled wire using a polysulfone group-containing polyhydroxypolyether resin as the fusing material is superior to the self-fusing enameled wire using a phenoxy resin as the fusing material. However, it does not have the heat resistance enough to be used as a magnet wire for electric coils such as fan motors, clutch motors, and electric component coils.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to perform heat fusion at a low temperature when fusing an electric coil. Another object of the present invention is to provide a heat-resistant self-fusing enameled wire capable of exhibiting excellent heat resistance such that excellent adhesive strength can be maintained even at a high temperature once heat-fused.

[0014]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a self-fusing enameled wire comprising a conductor and a fusion layer provided directly or via another insulator. A heat-resistant self-fusing enameled wire comprising a sulfone group-containing polyhydroxypolyether resin shown in Chemical formula 1 and an aromatic acid anhydride.

[0015]

Embedded image

[0016]

Next, an embodiment of the heat-resistant self-fusing enameled wire of the present invention will be described.

In the present invention, the sulfone group-containing polyhydroxypolyether resin represented by Chemical Formula 1 is not particularly limited as long as it is industrially practical, but is more preferably a molecular skeleton from the viewpoint of a balance between heat-fusibility and heat resistance. Those having a sulfone group content of 30 to 50% are suitable.

In the present invention, the aromatic acid anhydride is not particularly limited, but trimellitic anhydride having one acid anhydride group and one carboxyl group is preferably used.

In the present invention, the fusion layer is formed by blending 2 to 50 parts by weight of an aromatic acid anhydride with respect to 100 parts by weight of the sulfone group-containing polyhydroxy polyether resin shown in Chemical formula 1. Is preferred.

Here, the reason why the amount of the aromatic acid anhydride is limited to 2 to 50 parts by weight is that if the amount is less than 2 parts by weight, the effect of improving the adhesive strength at high temperatures is small. Conversely, if it is 50 parts by weight or more, the heat fusion temperature becomes high, and as a result, the heat fusion workability deteriorates.

In the present invention, the fusion layer is obtained by applying and baking a fusion paint obtained by dissolving a sulfone group-containing polyhydroxypolyether resin and an aromatic acid anhydride on an enameled wire.

The solvent for the fusing paint may be any solvent capable of dissolving the sulfonated polyhydroxypolyether resin and the aromatic acid anhydride, such as ketones such as cyclohexane, phenols such as cresol, and methyl carbitol. Carbitol and the like.

The fusion coating can be appropriately diluted with xylene, solvent naphtha or the like.

Further, lubricating properties can be imparted by blending a small amount of a fatty acid ester, a polyolefin or the like into the fusion coating.

[0025]

Next, examples of the heat-resistant self-fusing enameled wire of the present invention will be described together with comparative examples.

(Preparation of an H-class polyesterimide enameled wire) First, an H-class polyesterimide enameled wire having a coating thickness of 0.025 mm is applied to a conductive wire having a conductor diameter of 0.5 mm by coating and baking. I got

(Example 1) First, 100 parts by weight of a polyhydroxypolyether resin containing a sulfone group having a sulfone group content of 40% in the molecular skeleton and 2 parts by weight of trimellitic anhydride were collected. .

Next, these were dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to prepare a fused coating composition of Example 1 having a resin content of 20%.

Next, the fusion coating of Example 1 was applied and baked on the H-class polyesterimide enameled wire obtained above, whereby the heat-resistant self-heated coating of Example 1 having a fusion layer thickness of 0.010 mm was obtained. A fusible enameled wire was obtained.

FIG. 1 shows the heat-resistant self-fusing enameled wire of Example 1 thus obtained.

In FIG. 1, 1 is a conductor, 2 is a polyesterimide layer, and 3 is a fusion layer.

Example 2 First, 100 parts by weight of a polyhydroxypolyether resin containing a sulfone group having a content of 40% of a sulfone group in the molecular skeleton and 10 parts by weight of trimellitic anhydride were collected. .

Next, these were dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to prepare a fusion coating composition of Example 2 having a resin content of 20%.

Next, the fusion coating of Example 2 was applied and baked on the H-class polyesterimide enameled wire obtained above, whereby the heat-resistant self-heated coating of Example 2 having a thickness of 0.010 mm was obtained. A fusible enameled wire was obtained.

Example 3 First, 100 parts by weight of a polyhydroxy polyether resin containing a sulfone group having a 40% sulfone group content in a molecular skeleton and 25 parts by weight of trimellitic anhydride were collected. .

Next, these were dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to prepare a fused coating of Example 3 having a resin content of 20%.

Next, the fusion coating of Example 3 was applied and baked on the H-class polyesterimide enameled wire obtained above, whereby the heat-resistant self-adhesive film of Example 3 having a thickness of 0.010 mm was obtained. A fusible enameled wire was obtained.

Example 4 First, 100 parts by weight of a polyhydroxy polyether resin containing a sulfone group having a content of 40% of a sulfone group in the molecular skeleton and 50 parts by weight of trimellitic anhydride were collected. .

Next, these were dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to prepare a fused coating composition of Example 4 having a resin content of 20%.

Next, the fusion coating of Example 4 was applied and baked on the H-class polyesterimide enameled wire obtained above, whereby the heat-resistant self-adhesive film of Example 4 having a thickness of 0.010 mm was obtained. A fusible enameled wire was obtained.

Comparative Example 1 First, a sulfone group-containing polyhydroxypolyether resin having a sulfone group content of 40% in the molecular skeleton was dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to obtain a resin component. The fusion coating of Comparative Example 1 was prepared at a concentration of 20%.

Next, the self-fusing film of Comparative Example 1 having a fusion layer thickness of 0.010 mm was applied and baked on the H-class polyesterimide enamel wire obtained above. An adhesive enameled wire was obtained.

(Comparative Example 2) First, 100 parts by weight of a polyhydroxypolyether resin containing a sulfone group having a sulfone group content of 40% in the molecular skeleton and 60 parts by weight of trimellitic anhydride were collected. .

Next, these were dissolved in a mixed solvent consisting of cyclohexane and methyl carbitol to prepare a fused coating composition of Comparative Example 2 having a resin content of 20%.

Next, the fusion coating of Comparative Example 2 was applied and baked on the H-type polyesterimide enameled wire obtained above, whereby the self-fusing coating of Comparative Example 2 having a fusion layer thickness of 0.010 mm was obtained. An adhesive enameled wire was obtained.

(Comparative Example 3) A phenoxy resin (polyhydroxypolyether resin) was dissolved in a mixed solvent of cresol and cyclohexane to prepare a fusion coating material of Comparative Example 3 having a resin content of 20%.

Next, the fusion coating of Comparative Example 3 was applied and baked on the H-type polyesterimide enameled wire obtained above, whereby the self-fusing coating of Comparative Example 3 having a fusion layer thickness of 0.010 mm was obtained. An adhesive enameled wire was obtained.

(Comparative Example 4) A fused nylon coating having a resin content of 15% was prepared by dissolving a copolymerized nylon having a thermal softening point of 150 ° C in a mixed solvent containing cresol as a main component.

Next, the fusion coating of Comparative Example 4 was applied and baked on the H-type polyesterimide enameled wire obtained above, whereby the self-fusing coating of Comparative Example 4 having a fusion layer thickness of 0.010 mm was obtained. An adhesive enameled wire was obtained.

(Test Method for Self-fusing Enamelled Wire) a. Thermal fusibility test The thermal fusibility test was performed in accordance with NEMA standards.

First, the test self-fusing enameled wire was a 70-turn helical coil having an inner diameter of 4.3 mm.

Next, this helical coil was heated at a predetermined temperature to thermally fuse the adjacent lines.

Next, a buckling test was performed at room temperature (20 ° C.) on the helical coil in which the adjacent lines were heat-sealed, and the buckling strength was determined as the adhesive strength.

B. The adhesion test under high temperature was carried out in accordance with the NEMA standard in the same manner as the heat fusion test.

First, the test self-fusing enameled wire was a 70-turn helical coil having an inner diameter of 4.3 mm.

Next, this helical coil was heated at 200 ° C. for 1 hour.
Heating was performed for 0 minutes to thermally fuse the adjacent lines.

Next, the helical coil in which the adjacent lines were heat-sealed was left at a specified high temperature for 10 minutes, then subjected to a buckling test at the high temperature, and the buckling strength was determined as the adhesive strength.

(Test Results of Self-fusing Enamelled Wire) Table 1
Shows the results of these tests.

[0059]

[Table 1]

As can be seen from Table 1, the self-fusing enameled wire of Comparative Example 1 has excellent heat welding properties at 160 to 180 ° C., but has a small adhesive strength at high temperatures.

The self-fusing enameled wire of Comparative Example 2 has a large adhesive strength at a high temperature, but is inferior at 160 to 180 ° C. on one side.

The self-fusing enameled wire of Comparative Example 3 was 160
It is excellent in heat-weldability of up to 180 ° C or has the smallest adhesive strength at high temperature.

The self-fusing enameled wire of Comparative Example 4 was 160
It has excellent heat-fusibility at -180 ° C or has a considerably small adhesive strength at high temperatures.

On the other hand, the heat-resistant self-fusing enameled wires of Examples 1 to 4 are excellent in the heat welding property at 160 to 180 ° C. and also have high adhesive strength at high temperatures.

[0065]

According to the present invention, the heat-resistant self-fusing enameled wire is 1
It is excellent in heat welding at 60 to 180 ° C. and has high adhesive strength at high temperatures, and is industrially useful.

[Brief description of the drawings]

FIG. 1 shows a heat-resistant self-fusing enameled wire of Example 1 of the present invention.

[Explanation of symbols]

 Reference Signs List 1 conductor 2 polyesterimide layer 3 fusion layer

Claims (3)

[Claims] 1. A self-fusing enameled wire comprising a conductor and a fusion layer provided directly or via another insulating material, wherein the fusion layer comprises a sulfone group-containing polyhydroxy polyether resin represented by Chemical Formula 1. A heat-resistant self-fusing enameled wire comprising an aromatic acid anhydride. Embedded image 2. The fusion layer has a sulfone group-containing polyhydroxy polyether resin shown in Chemical Formula 1 based on 100 parts by weight.
2. The heat-resistant self-fusing enameled wire according to claim 1, wherein the composition comprises 2 to 50 parts by weight of an aromatic acid anhydride. 3. The heat-resistant self-fusing enameled wire according to claim 1, wherein the aromatic acid anhydride is trimellitic anhydride.