JP2890280B2 - Self-fusing insulated wire with excellent crazing properties and low-temperature adhesion - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-fusing insulated wire. More specifically, a crazing property suitable for winding a self-supporting coil such as a small flat motor coil (hereinafter abbreviated as a flat coil) used for driving a video tape recorder or a floppy disk.
The present invention relates to a hot-air bonding type epoxy self-fusing insulated wire having excellent low-temperature adhesion .

[0002]

2. Description of the Related Art A self-fusing insulated wire, in which a fusion coating is applied to a conductor via an insulation film and baked, is heated or subjected to a solvent treatment after winding on a coil, so that the fusion film dissolves or swells. Since the lines can be bonded and solidified, a self-supporting coil can be produced relatively easily, and is widely used for coil windings having a complicated shape such as a flat coil. Self-fusing insulated wires are broadly classified into two types, a hot-air bonding type and a solvent bonding type, depending on the method of processing between the wires. Recently, automation and speeding up of coil windings have been progressing, and self-fusing insulated electric wires of a hot-air bonding type, which are easy to cope with this, have come to be used frequently. In this hot-air bonding type self-fusing insulated wire, in consideration of winding properties, the fusing paint applied is mainly composed of a low-melting thermoplastic resin having a thermal softening temperature of about 100 to 150 ° C. Is used. In particular, when applying a hot-air bonding type self-fusing insulated wire to a high-speed coil winding, the adhesiveness at a low temperature, that is, the fusion coating is 100 to 150 mm.
It is desirable that the resin melts at a low temperature of about ° C and has a good resin flow. From this point of view, as a low-melting thermoplastic resin, a polyamide resin that has excellent adhesion and a melting point that can be arbitrarily selected is used as a main component of the fusion coating, and this fusion coating is used as another insulating film on a conductor. Polyamide-based self-fusing insulated wires coated and baked through a wire are often used.

[0003] However, the coil wound by using the polyamide-based self-fusing insulated wire has a drawback that when left under high humidity for a long time, it undergoes deformation due to moisture absorption, and the desired characteristics cannot be maintained. is there. The cause was found to be due to the high hygroscopicity of the polyamide resin, which is the main component resin of the fusion coating of the polyamide-based self-fusing insulated wire.
Accordingly, an epoxy-based self-fusing insulated wire was produced by applying and baking a fusion coating using only a thermoplastic high molecular weight epoxy resin having low hygroscopicity on a conductor via another insulating film. The coil wound by using the self-fusing insulated wire has little deformation due to moisture absorption, and is suitable as a coil exposed to a high humidity environment.

[0004]

In recent years, automation and speeding up of coil winding have been advanced, and a self-fusing insulated wire having excellent adhesion at low temperatures has been demanded. However, since the epoxy-based self-fusing insulated wire has crazing properties, the melting temperature of the fusion coating is higher than that of the polyamide-based self-fusing insulated wire, and the adhesiveness at low temperatures is inferior.
It could not cope with automation and high speed of coil winding. Therefore, in order to improve the low-temperature adhesion of the epoxy-based self-fusing insulated wire, a fusion paint made by adding a thermoplastic linear polyurethane resin synthesized from diol and diisocyanate to a high-molecular-weight epoxy resin is used as an insulated conductor. Attempts have been made to lower the glass transition temperature of the fused film by coating and baking on top, but the compatibility between the high molecular weight epoxy resin and the linear polyurethane resin is poor, and therefore the amount added is limited, so that a sufficient effect is obtained. Was not obtained.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and can cope with automation and high-speed coil winding. An object of the present invention is to provide a hot-air bonding type epoxy-based self-fusing insulated wire that melts at a low temperature of about 150 ° C., has a good resin flow, and has no crazing property.

[0006]

Means for Solving the Problems To achieve the above object, the present invention provides a film forming function having an average molecular weight of 30,000 to
To 100 parts by weight of high molecular weight epoxy resin of 50,000, modified ether of average molecular weight 15,000 to 25,000 type port Riesuteru resin 10
Was added to 100 parts by weight, self-bonding of the fused coating was dissolved in an organic solvent which was excellent in adhesion at crazing resistance and low-temperature baked coating directly or through another insulating film on the conductor On insulated wires.

The high molecular weight epoxy resin used as a main component of the fusion coating of the present invention has an average molecular weight of 30,000 or less obtained by an equimolar reaction between bisphenol A and epichlorohydrin.
50,000 thermoplastic high molecular weight epoxy resins. Specific examples include phenothoto YP50 (trade name of Toto Kasei Co., Ltd.), Epicron EXA192 (trade name of Dainippon Ink and Chemicals, Inc.), PKHH (trade name of Union Carbide Co., USA). When these high molecular weight epoxy resins are used alone, the fused film has poor crazing properties and poor adhesion at low temperatures.

Use as an additive resin in the fusing coating of the present invention
Is that modified ether type port Riesuteru resin, Po triethylene terephthalate part of ethylene glycol compositions, polyglycols and the solution depolymerization by a molecular weight 15,000 to 25,000 obtained by substitution reaction modified ether type polyester resins such as polyethylene glycol It is. This resin melts
Added for the purpose of improving the flexibility and thermal fluidity of the coating
It is soluble in organic solvents and used as a main component.
Good compatibility with the high molecular weight epoxy resin used
It also contributes well to the adhesion of the deposited film. Specific examples of the modified ether type polyester resin include Staphyx (trade name of Fuji Photo Film Co., Ltd.) . The reason why the addition amount of the modified ether type polyester resin is limited to 10 to 100 parts by weight is that when the addition amount is less than 10 parts by weight, the effect of improving the adhesiveness is small, and the addition amount exceeds 100 parts by weight. In this case, the self-fusing insulated wire wound around the bobbin after applying and baking the fusion paint to the outer periphery of the insulated conductor sticks, and there is a problem that the coil cannot be pulled out from the bobbin when wound. .

[0009]

[Action] modified ether that is added to the fusion coating of the present invention
Le type Po Riesuteru resin is excellent in compatibility with the high molecular weight epoxy resin which is a main component, a coating film even after baking commingled to uniform both the resin is obtained. And bisphenol A
Since the soft segment molecules having ester bonds are dispersed in the matrix of epoxy molecules having rigidity of the skeleton, the flexibility and thermal fluidity of the fusion coating are improved. Therefore, crazing properties and 10
Improves adhesion at low temperatures of about 0 to 150 ° C.

[0010]

EXAMPLES The contents of the present invention will be described below with reference to examples and comparative examples. Note that the present invention is not limited to the present embodiment. Table 1 is a resin composition table of the fusion coating materials of Examples 1 to 5 and Comparative Examples 1 to 3, Table 2 is a table showing characteristics of the self-fusing insulated wires of Examples and Comparative Examples, and Tables 3 and FIG. 1 is a table and a graph showing the adhesive properties of the self-fusing insulated wires of the examples and comparative examples.

[0011] YP50CS25B (Toto Kasei Co., trade name) 25% solution of fused paint Preparative Example 1-5 high molecular weight epoxy resin in an organic solvent, varying
Cresol advance as sex ether Po Riesuteru resin-
A stafix dissolved in a xylene mixed solvent was added according to the resin composition shown in Table 1 to prepare a 15% -concentration fused coating.

Comparative Examples 1 and 2 Paraprene P22 (trade name of Nippon Polyurethane Industry Co., Ltd.) previously dissolved in a cresol / xylene mixed solvent as a linear polyurethane resin was added to YP50CS25B.
To prepare a fused coating having a concentration of 15%. Comparative Example 3 YP50CS25B was diluted with a cresol-xylene mixed solvent to prepare a 15% -concentration fused coating.

When the stability of the varnish was examined with respect to the fusion coatings of these Examples and Comparative Examples, the coating of Comparative Example 1 was poor in stability because the linear polyurethane resin was separated three days after preparation.

[0014]

[Table 1]

Manufacture of self-fusing insulated wires A polyester imide paint was applied to a copper wire having a conductor diameter of 0.30 mm and baked so as to have a finish outer diameter of 0.324 mm, and then the fusion paints of the above Examples and Comparative Examples were finished. The self-fusing insulated wires of Examples 1 to 5 and Comparative Examples 1 to 3 were manufactured by coating and baking so that the outer diameter became 0.336 mm. The paint of Comparative Example 1 was used one day after preparation.

Characteristics Tests These self-fusing insulated wires were tested in accordance with JIS C3003 “Testing methods for enameled copper wire and enameled aluminum wire”, and the results are shown in Table 2. As a test of the adhesive properties of the self-fusing insulated wire, a helical coil sample having a diameter of 3 mm was prepared from the self-fusing insulated wires of the above Examples and Comparative Examples, and each was placed in a thermostat kept at 100 to 200 ° C. 10
After leaving for a minute, the sample was taken out, cooled at room temperature, and the adhesive strength between the wires was measured at a tensile speed of 10 cm / min using a tensile tester.
The results are shown in Table 3 and FIG. However, Embodiments 2 and 4 are not shown in FIG.

[0017]

[Table 2]

[0018]

[Table 3]

As is evident from Table 2, the self-fusing insulated wire of the present invention has no 3% or 5% stretched pinholes and has no crazing property. In contrast, the self-fusing insulated wires of Comparative Examples 2 and 3 had 3% and 5% stretched pinholes, indicating that they had crazing properties. As is clear from Table 3 and FIG. 1, the self-fusing insulated wire of the present invention has a heat treatment temperature of 10%.
It can be seen that adhesion occurs at 0 ° C. Note that Comparative Example 1 was also 100
Although it adheres at ℃, it is not practical for practical use due to poor stability of the paint. Further, Comparative Examples 2 and 3 start bonding at 120 ° C., but the adhesive strength is low, and even at a temperature of 140 ° C. or higher, the adhesive strength is lower than Examples 1 to 5.

[0020]

The self-fusing insulated wire of the present invention is modified into a high molecular weight epoxy resin as a component resin of the fusion coating.
Since the soft segment molecular having an ester bond and an ether bond in a matrix of epoxy resin molecules with a rigid bisphenol A skeleton is dispersed because the addition of ether Po Riesuteru resin, flexibility and heat fusion film Fluidity is imparted, and the crazing property and the adhesiveness at low temperatures, which have been problems with conventional epoxy-based self-fusing insulated wires, can be significantly improved. Therefore, the self-fusing insulated wire of the present invention is useful for obtaining a highly reliable self-supporting coil suitable for the application as the speed of coil winding increases.

[Brief description of the drawings]

FIG. 1 is a graph showing the adhesive properties of a self-fusing insulated wire.

Continuation of the front page (56) References JP-A-50-67473 (JP, A) JP-A-48-48979 (JP, A) JP-A-62-66504 (JP, A) JP-A-52-77728 (JP, A) , A) Fully open sho 49-80374 (JP, U) Fully open sho 61-194220 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01B 7/02 C08G 59/50 C08L 63/00 C09D 5/25 H01B 3/40

Claims (1)

(57) [Claims] An average molecular weight of 30,000 having a function of forming a coating film.
To 100 parts by weight of high molecular weight epoxy resin of 50,000, the average molecular weight 15,000 to 25,000 modified ether type port Riesuteru resin
10 to 100 parts by weight of this, the fusion paint was dissolved in an organic solvent, and baked directly on the conductor or through another insulating film and baked, characterized by crazing properties and low temperature
Self-fusing insulated wire with excellent adhesion .