JPH0644417B2 - Thermosetting self-bonding magnet wire - Google Patents

Description

The present invention relates to a self-bonding magnet wire. More specifically, thermosetting suitable for winding self-supporting coils, such as small flat motor coils (hereinafter abbreviated as flat coils) used for driving video tape recorders and floppy desks, which require dimensional accuracy. Type self-bonding magnet wire.

[Conventional technology]

A self-fusing magnet wire that is baked by applying a fusion coating on an electric conductor through an insulating coating, melts or swells the fusion coating by heating or treating with a solvent after winding the coil. Since it can be bonded and solidified, it is possible to relatively easily make a self-supporting coil, and it is widely used for a coil winding having a complicated shape such as a flat coil. Self-fusing magnet wires are roughly classified into two types, hot air bonding type and solvent bonding type, depending on the method of bonding between the lines. In general, in the hot air bonding type in which the fusion film is melt-bonded by heating, there is a limit to the temperature of the hot air blown onto the wire, and the thermal softening temperature is limited to a low melting point resin fusion film of about 120 to 150 ° C. Therefore, heat resistance is low. On the other hand, the solvent adhesive type, in which the fusion film of the self-adhesive magnet wire is dissolved and swelled with an alcohol solvent such as methanol or ethanol, and then adhered, a high melting point material can be used to produce a coil with good heat resistance. It is possible to

In recent years, with the introduction of a fully automatic coil winding machine for the aligned winding of the flat coil, the self-fusing magnet wire fusion coating has a small tolerance of finished dimensions in addition to heat resistance characteristics. There is a growing demand for winding properties that are excellent in alignment and have high dimensional accuracy.

The conventional solvent-bonding self-fusing magnet wire fusing paint is, for example, bisphenol A-based diglycidyl ether type epoxy resin added to alcohol-soluble polyamide resin and dissolved in an organic solvent containing cresol as a main component. The ones that are done are often used.

[Problems to be Solved by the Invention]

However, the self-fusing magnet wire coated and baked with this conventional fusing paint on the conductor through the insulating film is a fully automatic winding machine, and when the flat coil is aligned and wound while applying alcohol, Alcohol solubility of the fusion coating is too good, so even with a self-fusing magnet wire with little variation in the finished outer diameter, part of the fusion coating is scraped off at the alcohol application part and the outer diameter after alcohol application Became non-uniform, and coils were randomly wound, and thus the coil alignment rate was poor.

Further, the fusion coating swelled and dissolved by alcohol is apt to adhere to the jig of the above-mentioned winding machine, and there is a drawback that the jig is contaminated. In addition, the coil immediately after winding contains a large amount of alcohol in the fusion coating, so it is easily deformed.
There is a drawback that it takes time for this alcohol to volatilize from the inside of the coil and to obtain a strong bond.

In order to solve the above-mentioned drawbacks, a fusion-bonding paint consisting of three components in which a bisphenol A-based diglycidyl ether type epoxy resin and a block isocyanate compound are added to an alcohol-soluble polyamide resin has been proposed, which causes a problem of jig contamination of a winding machine. Was settled. However, even when this improved self-bonding magnet wire was used, the winding property was still poor and the coil alignment rate was low. Further, since the coil immediately after winding contains a large amount of alcohol and is swollen, there is a problem that it is easily deformed by an external force, and the coil size varies after the alcohol is volatilized.

In particular, when a coil is wound and then subjected to a heat treatment process in which the coil is soldered to a substrate using paste solder in the next step, the coil is further thermally deformed, and the dimension immediately after the winding is significantly deviated. was there.

The present invention was made in order to solve the problems of the above-mentioned prior art, and its object is to have a good winding property and a good coil alignment rate when wound on a flat coil, and to further prevent thermal deformation. It is an object of the present invention to provide a thermosetting self-bonding magnet wire capable of obtaining a coil that does not cause the above phenomenon.

[Means for Solving the Problems]

In order to achieve the above object, the present invention relates to 100 parts by weight of a phenoxy resin having a coating film forming function and an average molecular weight of 30,000 to 50,000 (hereinafter abbreviated as phenoxy resin), and an epoxy equivalent of 450 to 2,500 bisphenol A diglycidyl ether. Type epoxy resin (hereinafter abbreviated as bisphenol A epoxy resin) 10 to 50 parts by weight, novolac type epoxy resin having an epoxy equivalent of 210 to 250 (hereinafter abbreviated as novolac type epoxy resin) 10 to 50 parts by weight and amine curing agent 2 to
5 parts by weight is added, and a fusion paint prepared by dissolving this in an organic solvent is applied directly on the conductor or through another insulating film and baked, and it is insoluble in alcohol, melts in heat, and undergoes a thermosetting reaction. 1 fusion-bonding film is provided, and further 10-50 parts by weight of the bisphenol A epoxy resin and 5-15 parts by weight of the blocked isocyanate compound are added to 100 parts by weight of the alcohol-soluble polyamide resin on the outer periphery of the first fusion-bonding film. This is a thermosetting type self-bonding magnet wire provided with a second fusion coating which is soluble in alcohol by applying and baking a fusion coating which is dissolved in an organic solvent.

The phenoxy resin having a coating film forming function, which is the main component of the first fusion-bonding coating of the present invention, is a phenoxy resin having an average molecular weight of 30,000 to 50,000, and as a specific example, Phenothote YP50
(Toto Kasei Co., Ltd. product name), Epiclon EXA192 (Dainippon Ink and Chemicals, Inc. product name), and the like. When these thermoplastic phenoxy resins are used alone, the heat resistance of the fusion coating is inferior and the wound coil is likely to undergo thermal deformation. Therefore, it is necessary to add a thermosetting resin in order to improve heat resistance. As this resin, a novolac type epoxy resin is used, but since the number of functional groups per molecule, that is, the number of epoxy groups is large and the reactivity is high as compared with the bisphenol A type epoxy resin, a cured product having a high crosslinking density can be obtained. As a specific example, Epotote YDCN220M, YDCN220H,
YDCN220HH (trade name of Toto Kasei Co., Ltd.), ECN1273, ECN1280, E
CN1299 (trade name of Nippon Ciba-Geigy Co., Ltd.) and the like can be mentioned.

The bisphenol A epoxy resin is added as a cross-linking modifier to improve the flexibility of the fusion coating. As a specific example,
Epotote YD-011, YD-014, YD-017 (trade name of Toto Kasei Co., Ltd.), Epicoat 1001, 1004, 1007 (trade name of Yuka Shell Epoxy Co., Ltd.) and the like can be mentioned. The reason why the epoxy equivalent is limited to 450 to 2.500 is that the thermosetting property is deteriorated when the epoxy equivalent exceeds 2,500, and when the epoxy equivalent is less than 450, the shape of the epoxy resin becomes a semi-solid state and is applied. This is because the dryness to the touch of the film is deteriorated.

Further, an amine-based curing agent is indispensable as a curing agent for the above epoxy resin, and specific examples include Delamine CTU-100,
Examples include T-100S (trade name of Fuji Kasei Kogyo Co., Ltd.).

The bisphenol A epoxy resin is added in an amount of 10 to 50 parts by weight, the novolac type epoxy resin is added in an amount of 10 to 50 parts by weight, and the amine curing agent is added in an amount of 2 to 5 parts by weight, based on 100 parts by weight of the phenoxy resin. The reason for the limitation is that in these resins, if the amount is less than the limited weight part, the above effect due to addition is not observed, and if the amount exceeds the limited weight part, the fusion property of the fusion coating is significantly impaired.

The alcohol-soluble epoxy resin, which is the main component of the second fusion-bonding film of the present invention, has a melting temperature in consideration of the heat resistance of the coil.
180 ° C or higher, for example Ultramid 1C (BAS, Germany)
It is desirable to use a high melting point material such as F company's trade name), Amilan CM4000, and CM4001 (Toray's trade name).
The bisphenol A-based diglycidyl ether type epoxy resin having an epoxy equivalent of 450 to 2,500 added to the alcohol-soluble polyamide resin is the same resin as the bisphenol A-based epoxy resin used in the first fusion coating,
A specific example is the same, but in the second fusion coating, it is a resin added for improving the touch-drying property of the coating and adjusting the viscosity of the fusion coating. The reason for limiting the epoxy equivalent to 450 to 2,500 is that the compatibility with the alcohol-soluble polyamide resin becomes poor when the epoxy equivalent exceeds 2,500, and when the epoxy equivalent is less than 450, the shape of the epoxy resin is semi-solid. This is because it deteriorates the dryness to the touch and reduces the releasability from the coil winding jig. The blocked isocyanate compound is a cross-linking agent for the bisphenol A epoxy resin, and specific examples thereof include Millionate MS-50 and Coronate AP Stable (trade name of Nippon Polyurethane Company).

The reason why the addition amount of the bisphenol A-based epoxy resin to the alcohol-soluble polyamide resin is limited to 10 to 50 parts by weight and the addition amount of the blocked isocyanate compound to 5 to 15 parts by weight is that the addition amount of these resins is less than the limited weight part. This is because the above effect is not observed, and when the amount exceeds the limited weight part, the fusion property of the fusion coating is significantly impaired.

[Work]

A fusion-bonding coating composed of the alcohol-soluble polyamide resin as a main component, and an epoxy resin and a blocked isocyanate compound added thereto, which is a three-component fusion coating composition, is a low-molecular-chain epoxy resin in a matrix of the alcohol-soluble polyamide resin by coating and baking. Are uniformly distributed at a constant ratio, and the hydroxyl group in the main chain of the epoxy resin reacts with the blocked isocyanate compound, so that cross-linking with an interpenetrating network structure is formed. That is, by using the blocked isocyanate compound as a cross-linking agent, it is possible to control the magnitude of the intermolecular cross-linking density. Therefore, the addition of the blocked isocyanate compound acts to suppress the swelling degree or the solubility of the second fusion-bonding film in alcohol to an appropriate value.

Generally, in an aligned winding of a flat coil by applying alcohol, if the swelling degree or the solubility of the fusion coating is too good for alcohol, a part of the swelled or dissolved fusion coating adheres to the winding jig, or Since the outer diameter of the fusion coating also tends to fluctuate, the coil alignment rate decreases. On the contrary, when the swelling degree or the solubility in alcohol is poor, the adhesion between the wires becomes insufficient and the winding cannot be performed. Therefore, the second fusion-bonding film imparts an initial adhesive force required for bonding between coil wires in an aligned winding of a flat coil formed by applying alcohol, and further reduces dirt on the winding jig, Also increase the alignment rate.

On the other hand, the first fusion-bonded film is composed of a phenoxy resin as a main component and a bisphenol A-based epoxy resin, a novolac-type epoxy resin and an amine-based curing agent added thereto, and this fusion-bonded film is insoluble in alcohol. To be
In the process of applying alcohol and winding the flat coil, it does not swell or melt and does not contribute to the initial adhesion, but it melts in the heat treatment when soldering the coil to the printed circuit board using paste solder in the next process, After the wires are firmly fused together, the thermosetting reaction further promotes the crosslinking, which contributes to the improvement of the heat resistance of the coil. The fusion-bonding film of the present invention is insoluble in alcohol and melts by heat in place of the conventional alcohol-soluble fusion-bonding film, and further undergoes a thermosetting reaction.
The fusion coating and the alcohol-soluble second fusion coating are used. If the total thickness of the first fusion coating and the second fusion coating is equal to the thickness of the conventional fusion coating, Good, therefore, when viewed from the whole of the fusion coating, there is less fusion coating that swells and dissolves in alcohol, so the fluctuation of the outer diameter of the fusion coating during alcohol application in the flat coil winding process is reduced, Will increase the alignment rate. Further, since the alcohol content in the wound coil is also reduced, it is possible to suppress the dimensional change of the coil after alcohol volatilization or heat treatment.

〔Example〕

The contents of the present invention will be described below with reference to Examples and Comparative Examples.

Preparation of Fusion Coatings Table I is a resin composition table of the fusion coatings of Examples 1-8 and Comparative Examples 1-3.

25% solution of phenoxy resin in organic solvent Y
P50CS25B (trade name of Tohto Kasei Co., Ltd.), Epicoat 1007 (trade name of Yuka Shell Epoxy Co., Ltd.) which is a bisphenol A epoxy resin, and E which is a novolac type epoxy resin
CN1299 (Nippon Ciba Geigy Co., Ltd. trade name) and amine curing agent Delamin CTU-100 (Fuji Kasei Kogyo Co., Ltd. trade name) were added in the composition shown in Table I and dissolved in a mixed solvent of m-cresol and xylol to give a concentration of 20%. Fusing paint (Example-
I) was prepared. In addition, alcohol-soluble polyamide resin Ultramid 1C (trade name of BASF, Germany)
And Epicoat, a bisphenol A epoxy resin
1007 and a blocked isocyanate compound, Millionate MS-50 (trade name of Nippon Polyurethane Company), were added in the composition shown in Table I and dissolved in a mixed solvent of m-cresol and xylol to prepare a fusion coating composition having a concentration of 14% (Examples). -II) was prepared. As the fusion-bonding paint of Comparative Example, a fusion-bonding paint (Comparative Example-II) having a composition of Table I and a concentration of 14% was prepared in the same manner as in Example-II.

Production of Self-Fusing Magnet Wire The production of the thermosetting self-fusing magnet wire of the example and the self-fusing magnet wire of the comparative example will be described with reference to FIG.

Examples 1 to 8 As a conductor 1, a fusion coating (Example-I) having a phenoxy resin as a main component was first applied to a copper wire having a conductor diameter of 0.220 mm through a polyester insulating film 2 having a thickness of 6 μm to give a finished outer diameter. 0.24
Applying and baking so as to be 0 mm to provide the first fusion coating 3a,
Next, a fusion-bonding paint containing alcohol-soluble polyamide resin as a main component (Example-II) was applied to the outer periphery of the finished outer diameter of 0.248 mm.
The second fusion coating 3b was formed by coating and baking so as to obtain a thermosetting self-bonding magnet wire comprising the first fusion coating 3a and the second fusion coating 3b as the fusion coating 3.
(The thickness ratio between the first fusion coating and the second fusion coating is 5: 5 in the present embodiment, but it may be in the range of 4: 6 to 6: 4.) Comparison Examples 1 to 3 As a conductor, a fusion coating composition (Comparative Example-II) containing alcohol-soluble polyamide resin as a main component was applied on a copper wire having a conductor diameter of 0.220 mm through a polyester insulating film having a thickness of 6 μm to give a finishing outer diameter of 0.248. It was coated and baked so that the thickness became mm, and a self-bonding magnet wire was manufactured.

These self-bonding magnet wires are JISC3003
"Test method for enamel copper wire and enamel aluminum wire"
The test was conducted based on the test results and the results are shown in Table II.

Flat coil winding and characteristics Using a single-axis fully automatic winding machine, while applying ethanol to the self-bonding magnet wire of the example and the comparative example, the flat coil was wound at a rotation speed of 1,500 rpm. . For each example, 100 flat coils were wound and tested for coil alignment rate, jig contamination, coil thermal deformation, etc., and the results are shown in Table III. The coil alignment rate was calculated by the following equation.

In addition, the thermal deformation test was carried out at a thickness of 200 ° C x 1 immediately after winding the coil.
The thickness after 0 minute heat treatment is measured with a micrometer, and the value immediately after winding is subtracted from the value after heat treatment. When the value is 0 or-, it is judged that there is no coil swelling (no thermal deformation). When the value was +, it was determined that there was swelling of the coil (there was thermal deformation).

[Effects of the Invention] The thermosetting self-bonding magnet wire of the present invention is shown in Table II.
As is clear from the characteristics shown in I, a coil having a better alignment rate than the conventional self-bonding magnet wire, less jig contamination, and less thermal deformation can be obtained. This is because the thermosetting self-adhesive magnet wire of the present invention is composed mainly of a first fusion-bonding film which is insoluble in alcohol containing phenoxy resin as a main component, is melted by heat, and undergoes a thermosetting reaction, and an alcohol-soluble polyamide resin. This is because it has a double-structured fusion-bonding film composed of the alcohol-soluble second fusion-bonding film. Further, the second fusion coating contributes to the initial adhesion between the wires in the winding by the application of alcohol, while the first fusion coating does not swell or dissolve in the alcohol, but is melted by the heat treatment after the winding and is then melted. After firmly adhering the gaps, the thermosetting reaction causes crosslinking to proceed, which contributes to improvement in heat resistance of the coil. Since only the second fusion coating swells or dissolves with alcohol in the fusion coating, the outer diameter variation of the fusion coating during alcohol application is reduced, and the coil alignment rate and winding property become extremely good, and the flat coil The productivity in manufacturing is greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an embodiment of the thermosetting self-bonding magnet wire of the present invention. 1 ... conductor, 2 ... insulating film, 3 ... fusion film, 3a ...
First fusion coating, 3b ... Second fusion coating.

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-48-31477 (JP, A) JP-A-50-144089 (JP, A) JP-A-51-101520 (JP, A) JP-A-52- 9881 (JP, A) JP 53-41723 (JP, A) JP 56-97911 (JP, A) JP 58-175207 (JP, A) JP 59-20916 (JP, A) JP-A-59-159640 (JP, A) JP-A-2-135612 (JP, A) JP-A-2-135613 (JP, A) Actually open Sho-50-34786 (JP, U) Actual-open Sho-50-34787 (JP, U) Actually open 50-43876 (JP, U) Actually open 50-29735 (JP, Y1)

Claims (1)

[Claims] 1. An average molecular weight of 30,000 to have a film forming function.
Epoxy equivalent of 450 per 100 parts by weight of 50,000 phenoxy resin
To 2,500 bisphenol A-based diglycidyl ether type epoxy resin 10 to 50 parts by weight, epoxy equivalent 210 to 250 novolak type epoxy resin 10 to 50 parts by weight, and amine curing agent 2 to 5 parts by weight are added. A fusing paint dissolved in a solvent is applied and baked directly on a conductor or through another insulating film, and 100 parts by weight of an alcohol-soluble polyamide resin is further coated with bisphenol A-based diglycidyl ether type having an epoxy equivalent of 450 to 2,500. A thermosetting self-bonding magnet wire, characterized in that 10 to 50 parts by weight of an epoxy resin and 5 to 15 parts by weight of a blocked isocyanate compound are added, and a fusion paint prepared by dissolving this in an organic solvent is applied and baked.