JPH07272541A - Insulated electric wire - Google Patents

Abstract

PURPOSE:To manufacture an insulated electric wire having excellent solder peeling property and high heat resistance by forming an insulating coating on a conductor by a polyesterimide insulating paint containing polyesterimide resin consisting of a dihydric alcohol containing an imide group having a specified formula, polyhydric alcohol, and a dicarboxylic acid. CONSTITUTION:An insulating coating is formed on a conductor from a polyesterimide insulating coating containing polyesterimide resin composed of a dihydric alcohol (tetracarboxylic acid, etc.) containing an imide group having a formular shown (wherein R1= bivalent organic group, R2= divalent aliphatic group with 2-6 carbon number), polyhydric alcohol (ethylene glycol, glycerin, etc.), polycarboxylic acid (isophthalic acid, trimellitic acid, etc.), and/or their derivatives. Consequently, an insulated electric wire having heat resistance about not lower than 300 deg.C heat resistant softening temperature and for which solder peeling treatment can be carried out under immersion conditions at 440 deg.C for about 10 seconds or shorter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated wire, and more particularly to an insulated wire coated with a polyesterimide resin having excellent solder releasability and heat resistance.

[0002]

2. Description of the Related Art In recent years, with the reduction in size and weight of electric and electronic devices, the number of thin wire type insulated wires used for motors and transformers has been increasing. In addition, with the increase in brightness and definition of televisions and displays, the number of thin-wire type insulated wires used for cathode ray tube deflection yokes is increasing.

By the way, the insulated electric wires used in these electronic devices are obtained by applying an insulating coating material on a conductor and then baking it to form an insulating film, and the insulating film at the end is peeled off before use. The terminal stripping method includes mechanical stripping, thermal stripping, chemical stripping, solder stripping, etc. Among them, the solder stripping method has features such as no damage to the conductor wire and short treatment time. Therefore, it is considered that the solder peeling method is particularly suitable for peeling the end of the thin wire type insulated wire.

Therefore, a polyurethane insulated wire is used as an insulated wire that can be peeled off from solder, but such a polyurethane insulated wire has a heat-resistant classification of A to E class insulation,
It cannot be used for applications requiring higher heat resistance.
Polyamide-imide insulated wires and the like are known as insulated wires having heat resistance equal to or higher than F-type insulation and solder releasability, but they are used only in limited applications because of their high price. So, in order to solve this problem,
A polyesterimide insulated electric wire, which is an insulated electric wire having a heat resistance higher than that of type F insulation and a solder peeling property, and a relatively low price, has been developed.

[0005]

However, these polyester-imide insulated wires require a dipping condition of 450 ° C. for about 10 seconds in order to completely remove the insulating film, so that there is a limit to the improvement of the terminal treatment speed. was there. For this reason, there has been a demand for an insulated wire that can be subjected to terminal treatment at a lower temperature and a shorter time.

Further, the polyesterimide insulating coatings used for these polyesterimide insulated wires are generally synthesized from a divalent carboxylic acid containing an imide group in the molecule as a raw material, so that the solvent used for the synthesis (cresol,
There is a problem that the raw material is difficult to dissolve in (phenol etc.), the resin synthesis becomes a heterogeneous reaction, a large force is required for stirring, etc.
It has been desired to improve the workability of insulating paint.

Therefore, the present inventors have solved the above problems,
As a result of earnest research to obtain an insulated wire that has the same heat-resistant softening temperature as F type polyester imide insulated wire and solder releasability at low temperature in a short time and has excellent workability of the raw material insulating paint, This led to the present invention.

[0008]

The insulated wire according to the present invention is summarized in the general formula (1).

[Chemical 3] (In the formula, R ₁ is a divalent organic group, and R ₂ is ₂ having 2 to 6 carbon atoms.
A valent aliphatic group is shown. ) A dihydric alcohol containing an imide group represented by), a polyhydric alcohol, and a polyesterimide insulating coating containing a polyesterimide resin containing one or both of a polycarboxylic acid and its derivative as a constituent, This is because an insulating film was formed on the wire.

In such an insulated wire, R ₁ in the general formula (1) is

[Chemical 4] One or more selected from the group shown in.

In addition, in such an insulated wire, a fusion bonding layer is further formed on the insulating coating so as to have a self-fusing property.

[0011]

The insulated wire of the present invention is a polyesterimide containing a polyesterimide resin containing a dihydric alcohol containing an imide group, a polyhydric alcohol, and / or a polyhydric carboxylic acid or a derivative thereof. An insulating coating is formed on the conductor with an insulating paint. Since the polyester imide resin uses a dihydric alcohol containing an imide group as a raw material, the solubility of the raw material in an organic solvent is excellent, and the addition amount of the dihydric alcohol containing the imide group can be increased. It is possible to obtain a polyesterimide resin having a high imide group content. Further, the resin synthesizing system becomes a homogeneous system, and the workability at the time of synthesizing can be improved. Therefore, the insulated wire of the present invention having an insulating film formed of a polyesterimide insulating coating containing such a polyesterimide resin as a main component has excellent heat resistance and good solder releasability as well as mechanical properties, electrical properties, and chemical properties. Is to have. Specifically, the insulated wire of the present invention has excellent heat resistance of 300 ° C. or higher in heat resistance and solder peelability, which are conventionally considered to be contradictory properties, and at 440 ° C. Solder stripping treatment is possible under immersion conditions of 10 seconds or less, and the raw material coating material has excellent workability during synthesis.

[0012]

EXAMPLES Next, the insulated wire of the present invention will be described in more detail with reference to the preferred embodiments of the present invention.

The polyesterimide resin contained in the polyesterimide insulating coating material, which is the raw material coating material for the insulated wire of the present invention, has the general formula (1):

[Chemical 5] (In the formula, R ₁ is a divalent organic group, and R ₂ is ₂ having 2 to 6 carbon atoms.
A valent aliphatic group is shown. In the organic solvent, a dihydric alcohol containing an imide group represented by), a polyhydric alcohol, and either one or both of a polyvalent carboxylic acid and its derivative (hereinafter referred to as a polyvalent carboxylic acid). Obtained by reacting.

First, the raw material for synthesizing the polyesterimide resin will be described. The dihydric alcohol containing an imide group represented by the general formula (1) is represented by the general formula (2).

[Chemical 6] (In the formula, R ₁ represents a divalent organic group.) Any one kind or a mixture of two or more kinds of a tetracarboxylic acid represented by the following formula, an anhydride thereof, or a lower alkyl ester thereof (hereinafter referred to as tetracarboxylic acid). Etc.) and the general formula (3) HO-R.
_2- NH ₂ (3) (wherein, R ₂ represents a divalent aliphatic group having 2 to 6 carbon atoms) is reacted with an amino alcohol by a conventionally known method. However, the method is not particularly limited to this method.

Further, instead of the dihydric alcohol containing an imide group represented by the general formula (1), a dihydric alcohol which is a precursor thereof may be used, and the dihydric alcohol which is the precursor is Can be obtained by changing the reaction conditions (reaction temperature, reaction time, etc.) using the same raw materials as above.

Here, R ₁ in the general formula (2) is a divalent organic group, and it is possible to use all kinds of tetracarboxylic acids and the like.

[Chemical 7] One or more kinds of tetracarboxylic acid having an organic group selected from the group shown in 1 above are preferably used. Among them, R
It is particularly preferred that ₁ is an ethylene group.

R ₂ in the general formula (3) is a divalent aliphatic group having 2 to 6 carbon atoms, and

[Chemical 8] One or more kinds of amino alcohols having an organic group selected from the group shown in are preferably used. Among them, R ₂
Is particularly preferably an ethylene group.

Next, as the polyhydric alcohol, aliphatic 2
It is preferable to use a monohydric alcohol alone or to use an aliphatic dihydric alcohol and an aliphatic trihydric alcohol in combination.

As the aliphatic dihydric alcohol, for example,
Ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, various butane-, pentane-, or hexanediol (eg 1,3- or 1,4- Butanediol,
1,5-pentanediol, 1, 6-hexanediol, hexylene glycol), 1,4-buten-2-diol, 2,2-dimethyl-1,3-diol, 2-ethyl-2-butyl - Propane-1,3-diol, 1,4-dimethylolcyclohexane, 1,4-butenediol, water-added bisphenols (for example, water-added bisphenol A or its homologues),
Cyclic glycols (eg 2,2,4,4-tetramethyl-1,3-
Cyclobutanediol, hydroxynon-di-β-hydroxyethyl ether, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, trimethylene glycol,), octylene glycol and the like, ethylene glycol, propylene glycol, and 1,6-hexanediol is preferable, and ethylene glycol is particularly preferable.

As the aliphatic trihydric alcohol, for example,
Glycerin, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane and the like can be mentioned, with glycerin being particularly preferred. In addition, polyhydric alcohols other than aliphatic ones such as trishydroxyethyl isocyanurate may be used.

Next, as the polyvalent carboxylic acid, it is preferable to use a divalent carboxylic acid alone or to use a divalent carboxylic acid and a trivalent carboxylic acid in combination. Further, a derivative thereof may be used instead of or in combination with the polyvalent carboxylic acid.

Examples of the divalent carboxylic acid include isophthalic acid, terephthalic acid, various naphthalene dicarboxylic acids, diphenyl-2,2'-dicarboxylic acid and diphenyl-2,3'-.
Dicarboxylic acid, diphenyl-3,3'-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenylmethane-2,2'-dicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylethane-4,4 ' -Dicarboxylic acid, diphenyl sulfone
-4,4'-dicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, benzophenone-4,4'-dicarboxylic acid, phthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, adipic acid, succinic acid, maleic acid , Sebacic acid, isosebacic acid, dimer acid, tetrachlorophthalic acid, 4,4′-dicarboxy-diphenylpropane and the like. Of these, terephthalic acid and isophthalic acid are particularly preferable.

As the divalent carboxylic acid, it is also possible to use a divalent carboxylic acid containing an imide group. The divalent carboxylic acid containing an imide group can be obtained by reacting a tricarboxylic acid anhydride with a diamine or a diisocyanate by a conventionally known method. Alternatively, it can be synthesized from tetracarboxylic dianhydride and aminocarboxylic acid. Of these, divalent carboxylic acids containing an imide group obtained from tricarboxylic acid anhydride and aromatic diamine or aromatic diisocyanate are particularly preferable.

As the tricarboxylic acid anhydride, trimellitic acid anhydride, various naphthalene tricarboxylic acid anhydrides, 3,4,4'-diphenyltricarboxylic acid anhydride, 3,
4,4'-diphenylmethanetricarboxylic anhydride, 3,4,4 '
-Diphenyl ether tricarboxylic acid anhydride, 3,4,4'-
Examples thereof include benzophenone tricarboxylic acid anhydride, and trimellitic acid anhydride is particularly preferable.

Further, as the aromatic diamine, for example,
4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylsulfone,
4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl, 3,3'-
Diaminodiphenyl sulfone, 3,3'-dimethyl-4,4'-
Bisphenyldiamine, 1,4-diaminonaphthalene, 1,5-
Examples thereof include diaminonaphthalene, m-phenylenediamine, p-phenylenediamine, m-xylylenediamine, p-xylylenediamine and the like.

As the aromatic diisocyanate,
Diisocyanates corresponding to the above aromatic diamines can be mentioned.

Examples of the trivalent carboxylic acid include trimellitic acid, hemimellitic acid, various naphthalenetricarboxylic acids, 3,4,4'-diphenyltricarboxylic acid, 3,4,4'-diphenylmethanetricarboxylic acid, 3,4, Examples thereof include 4'-diphenyl ether tricarboxylic acid and 3,4,4'-benzophenone tricarboxylic acid, with trimellitic acid being particularly preferred.

Examples of the derivatives of these polyvalent carboxylic acids include carboxylic acid esters, carboxylic acid halides, and carboxylic acid anhydrides. These substituents are
All of the carboxyl groups of the polycarboxylic acid may be substituted, or some of them may be substituted. Particularly preferred among these derivatives are carboxylic acid lower alkyl esters, particularly methyl ester or ethyl ester, and carboxylic acid halides and carboxylic acid anhydrides such as dimethyl terephthalate, dimethyl isophthalate and trimellitic anhydride. Is preferably used.

It is also possible to use, as a raw material for the polyesterimide resin, a polyhydric alcohol obtained by esterifying the carboxyl group of the polyhydric carboxylic acid with one hydroxyl group of the aliphatic dihydric alcohol. .

As an example of the solvent for synthesizing the polyesterimide resin, a solvent having a phenolic hydroxyl group,
For example, phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5- Xylenol, o-n-propylphenol, 2,4,6-trimethylphenol, 2,3,5-trimethylphenol, 2,4,5-trimethylphenol, 4-ethyl-2-
Mention may be made of methylphenol, 5-ethyl-2-methylphenol, and cresylic acid which is a mixture thereof. Further, polar solvents such as N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-dimethylsulfoxide, and N-methyl-2-pyrrolidone are also included.

Further, the above solvent may be used as an aliphatic hydrocarbon, an aromatic hydrocarbon, an ether, an acetal, a ketone,
It is also possible to use it after diluting it with a solvent such as ester.

Examples of aliphatic hydrocarbons and aromatic hydrocarbons include n-heptane, n-octane, cyclohexane, decalin, dipentene, pinene, p-menthane,
Decane, dodecane, tetradecane, benzene, toluene, xylene, ethylbenzene, diethylbenzene, isopropylbenzene, amylbenzene, p-cymene, tetralin, or a mixture thereof, petroleum naphtha, coal tar naphtha, solvent naphtha and the like can be mentioned.

A polyesterimide resin, which is a main component of the polyesterimide insulating coating used in the present invention, can be obtained from the above raw materials, and a method for producing the same will be described below. First, the tetracarboxylic acid or the like and an amino alcohol are mixed in an organic solvent at a molar ratio of 1: 2, and 1 to 150 ° C. to 200 ° C. while removing water generated in the reaction process.
After reacting for about 8 hours, a solution of a dihydric alcohol containing an imide group represented by the general formula (1) is obtained. Next, this solution is cooled to room temperature, and then the polyhydric alcohol and polycarboxylic acid are added to the solution and the temperature is slowly raised to about 200 ° C., and the reaction is performed at 200 ° C. to 210 ° C. for 3 hours to 10 hours. Then, the polyesterimide resin of the present invention is obtained by polyesterification. The ratio of using each raw material at this time is not particularly limited, but a dihydric alcohol containing an imide group (referred to as imide alcohol) is used as the heat resistance of the obtained polyesterimide resin,
The lower limit is 5 equivalent%, and further 1 from the characteristics such as solder releasability.
0 equivalent% is preferable, and the upper limit is preferably 50 equivalent%, further preferably 40 equivalent%. In addition, the total of all alcohols including imide alcohol has a lower limit of 50 equivalent%, further 55 equivalent%, and an upper limit of 70 equivalent%, and further 60 equivalent% relative to the ratio of all polycarboxylic acids. preferable.

Imido alcohol has excellent solubility in the solvent used, and evenly dissolves in the solvent at room temperature.
The amount of imide alcohol added can be increased to the above ratio. In addition, this synthesis is a homogeneous system, and compared with the conventional method in which a polyesterimide resin is synthesized from a divalent carboxylic acid containing an imide group and a polyhydric alcohol, a large force is not required for stirring, and the work during the synthesis is performed. The property is improved.

Further, such polyesterimide resin is
The tetracarboxylic acid dianhydride and the like and amino alcohol are mixed in the same manner as above, and stirred at 0 to 100 ° C. for 10 minutes to several hours to obtain a dihydric alcohol which is a precursor of imide alcohol. It may be synthesized by reacting with a polyhydric alcohol, a polycarboxylic acid or the like in the same manner as described above and performing polyesterification at the same time as imidization.

Furthermore, the tetracarboxylic acid or the like, amino alcohol, polyhydric alcohol, and polyhydric carboxylic acid are mixed in the same manner as above, and the temperature is slowly raised to about 200 ° C., and 200 ° C. to 210 ° C. You may use the method of reacting at 3 degreeC for 3 hours-10 hours, and making it imidize and polyester-form simultaneously.

Further, such polyesterimide resin is
First, after obtaining a polyester resin by a known method from a polyhydric alcohol and a polycarboxylic acid, the dihydric alcohol containing the imide group is added to the solution, and the imide group is introduced into the polyester by transesterification. Can also be obtained by Alternatively, in a solution of a polyester resin composed of a polyhydric alcohol and a polycarboxylic acid, a dihydric alcohol which is a precursor of the dihydric alcohol containing an imide group, or the tetracarboxylic acid and the like which are raw materials thereof and an amino acid. A method of introducing an imide group into the polyester by adding an alcohol and transesterifying at the same time as the imidization may be used.

In these methods, a catalyst or the like generally used for polyester synthesis may be added.

The polyesterimide resin obtained by the above method is diluted to a desired concentration with the solvent used for synthesis or another appropriate solvent to obtain a polyesterimide insulating coating, and the polyesterimide insulating coating is applied on a conductor. By applying and baking on, an insulating film is formed on the conductor to obtain the insulated wire of the present invention. In order to improve workability when obtaining the insulated wire of the present invention, additives such as metal desiccant, titanic acid or zirconate compound, stabilized polyisocyanate, phenol formaldehyde resins, epoxy resin, and silicone resin are added. You may use the polyester imide insulating paint which added such.

As the metal desiccant, zinc, calcium,
Or lead octoate or linoleate, for example,
Examples thereof include zinc octoate, calcium naphthenate, zinc naphthenate, lead naphthenate, lead linoleate, calcium linoleate, zinc resinate, and others, and manganese naphthenate, cobalt naphthenate, and the like.

Examples of the titanic acid compound include tetraalkyl titanates such as tetraisopropyl titanate, tetrabutyl titanate, tetrahexyl titanate, tetramethyl titanate, tetrapropyl titanate and tetraoctyl titanate. Also useful are tetraalkyltitanium chelates obtained by reacting tetraalkyltitanate with octyleneglycol, triethanolamine, 2,4-pentadiene, acetoacetic acid ester and the like. Further, tetraalkyl titanium acylate obtained by reacting tetraalkyl titanate with stearic acid is also useful.

Examples of zirconate compounds include tetraalkyl zirconates, zirconium chelates, and zirconium acylates corresponding to the above titanic acid compounds.

As the stabilized polyisocyanate, for example, 2,4-tolylene diisocyanate cyclic trimer, 2,6-
Cyclic trimer of tolylene diisocyanate, dimer of diphenylmethane-4,4'-diisocyanate, reaction product of diphenylmethane-4,4'-diisocyanate and trimethylolpropane in a molar ratio of 3: 1, 2,4-tri Reaction product of diisocyanate and trimethylolpropane in a molar ratio of 3: 1, reaction product of 2,6-tolylenediisocyanate and trimethylolpropane in a molar ratio of 3: 1, 2,4-tolylenediisocyanate and trimethylolethane Molar ratio of 3 to 1
And a stabilized polyisocyanate obtained by blocking the reaction product of 2,6-tolylene diisocyanate and trimethylolethane in a molar ratio of 3: 1 with phenol or cresol. Also, diphenylmethane-
Also included are stabilized isocyanates in which 4,4'-diisocyanate is blocked with xylenol.

Examples of phenol formaldehyde resins include melamine formaldehyde resin, cresol formaldehyde resin, and xylene formaldehyde resin.

To obtain the insulated wire of the present invention, the polyesterimide insulating coating material obtained by the above method is applied onto the conductor wire by a conventionally known method, for example, a method such as a felt drawing method or a die drawing method, and baking is performed. A method of baking with a furnace is used. As the conductive wire used here, a commonly used conductive wire, for example, a wire material of copper, silver, aluminum or stainless steel can be used, but a copper wire is particularly preferable.

The insulated wire of the present invention may be coated with an insulating coating material on the conductive wire by the above method and baked, and then a fusion layer may be further formed on the insulation film to impart self-bonding property. Specifically, on the polyesterimide insulating film of the insulated wire obtained by the above method, a fused layer is further applied and baked by the same method as described above to obtain an insulated wire having self-fusing property. . As the fusing layer, a resin capable of imparting self-fusing property, for example, a general thermoplastic resin or a thermosetting resin can be used.

The insulated wire obtained by the above-mentioned method has excellent heat resistance of a softening temperature of 300 ° C. or more, and can be subjected to a solder peeling treatment under a dipping condition of 440 ° C. for 10 seconds or less. It is a good thin wire type insulated wire having the above heat resistance. Alternatively, a fused layer may be formed on the polyesterimide insulating film to form an insulated wire having a self-fusing property.

Although the embodiments of the insulated wire according to the present invention have been described above, the present invention is not limited to these embodiments. For example, the insulated wire of the present invention has a colored coating on the insulating film. May be applied and baked for coloring, or may be prepared by applying a polyesterimide insulating coating material in an appropriate color and applying and baking it on a conductor. Also, an insulated electric wire other than the thin wire type may be used.
In addition, the present invention can be carried out in a mode in which various improvements, changes and modifications are made based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

Example 1 2 equipped with a stirrer, a nitrogen gas introducing pipe, a thermometer and a cooling pipe
In a liter 4-neck flask, 500 g of cresol and 205 g of ethylene glycol bistrimellitic dianhydride.
(0.5 mol) was added and dispersed. In this dispersion,
61 g (1 mol) of monoethanolamine was gradually added dropwise, 100 ml of xylene was further added, and the mixture was heated to 180 ° C for 3 times.
After the temperature was raised over a period of time, the reaction was allowed to proceed for 3 hours at this temperature while removing the produced water to obtain a dihydric alcohol solution containing an imide group. This dihydric alcohol was uniformly dissolved in cresol. Next, after cooling the system to around room temperature, 62 g (1 mol) of ethylene glycol, 96 g (0.5 mol) of trimellitic anhydride, 49 g (0.25 mol) of dimethyl terephthalate and 2.3 g of tetrabutyl titanate as a catalyst were added. And stir 20
The temperature was raised to 0 ° C. over 6 hours, and the reaction was continued at this temperature for 5 hours to obtain a polyesterimide resin. After cooling the obtained polyester imide resin to 60 ° C. and adding a proper amount of cresol and 2.5% of tetrabutyl titanate to the non volatile matter to obtain a polyester imide insulating coating having a non volatile content of 38% and a viscosity of 30 poise. , This insulating paint is passed through a die baking machine 7 times in a horizontal baking oven, and the maximum temperature is 5
At 00 ° C., it was baked on a φ0.40 mm copper wire to obtain an insulated electric wire having a film thickness of 0.02 mm.

The characteristics of this insulated wire are flexibility, adhesion, softening temperature (° C), breakdown voltage (kV), 440 ° C and 4
Test for solder peelability (sec) at 60 ° C
The test was performed according to the JISC 3003-1084 enamel copper wire and enamel aluminum wire test method, and the results are shown in Table 1.

[0052]

[Table 1]

Further, a fusible coating material made of a thermoplastic polyamide resin was applied to this insulated wire in a horizontal baking furnace by a die drawing method and baked to obtain an insulated wire having self-bonding property. With respect to this insulated wire having self-bonding property, a test for softening temperature (° C.) and solder peeling property (sec) at 440 ° C. and 460 ° C. was conducted in the same manner as above
The results are shown in Table 2.

[0054]

[Table 2]

Example 2 The same amount of cresol, bistrimellitic acid ethylene glycol dianhydride, monoethanolamine, and xylene were added to the same apparatus as in Example 1 by the same method, and the mixture was stirred at room temperature for 1 hour, A solution of a dihydric alcohol having an amic acid structure, which is a precursor of a dihydric alcohol containing an imide group, was obtained. To this system were added the same amounts of ethylene glycol, trimellitic anhydride, dimethyl terephthalate, and 2.3 g of tetrabutyl titanate as a catalyst, and the reaction was carried out under the same conditions as in Example 1 to obtain a polyesterimide resin. Got Using the obtained polyesterimide resin, the nonvolatile content was 40% and the viscosity was 3 in the same manner as in Example 1.
After obtaining 0 poise of polyesterimide insulating paint, an insulated wire and an insulated wire having self-bonding property were obtained from this insulating paint in the same manner as in Example 1. The characteristics of this insulated wire and the insulated wire having the self-bonding property were examined in the same manner as in Example 1, and the results are also shown in Tables 1 and 2.

Example 3 By the same method as in Example 1, a dihydric alcohol containing an imide group was obtained. Next, after cooling this system to around room temperature, 124 g (2 mol) of ethylene glycol, 64 g (0.33 mol) of trimellitic anhydride, 49 g (0.25 mol) of dimethyl terephthalate, 4,4'-diaminodiphenylmethane and anhydrous Divalent carboxylic acid containing imide group obtained by reacting trimellitic acid at a molar ratio of 1: 1
3.7 g (0.25 mol) and 2.8 g of tetrabutyl titanate as a catalyst were added and heated in the same manner as in Example 1 to obtain a polyesterimide resin. Here, the divalent carboxylic acid containing an imide group was insoluble in cresol and thus formed a dispersion liquid, but dissolved as the reaction proceeded. Using the polyesterimide resin thus obtained, in the same manner as in Example 1, the nonvolatile content was 38% and the viscosity was 20 po.
After obtaining the polyesterimide insulating paint of ise, an insulated electric wire and an insulated electric wire having a self-bonding property were obtained from this insulating paint by the same method as in Example 1. The characteristics of this insulated wire and the insulated wire having the self-bonding property were examined in the same manner as in Example 1, and the results are also shown in Tables 1 and 2.

Example 4 By the same method as in Example 1, a dihydric alcohol containing an imide group was obtained. Next, after cooling this system to around room temperature, 47 g (0.75 mol) of ethylene glycol, 31 g (0.17 mol) of glycerin, and 9 parts of trimellitic anhydride
6 g (0.5 mol), dimethyl terephthalate 49 g
(0.25 mol) and 2.3 g of tetrabutyl titanate as a catalyst were added and reacted under the same conditions as in Example 1 to obtain a polyesterimide resin. Using the obtained polyester imide resin, a polyester imide insulating paint having a nonvolatile content of 36% and a viscosity of 30 poise was obtained in the same manner as in Example 1, and then the insulated wire and the self-insulating wire were prepared in the same manner as in Example 1. An insulated electric wire having a fusion property was obtained. The characteristics of this insulated wire and the insulated wire having the self-bonding property were examined in the same manner as in Example 1, and the results are also shown in Tables 1 and 2.

Comparative Example 1 3 equipped with a stirrer, a nitrogen gas introducing pipe, a thermometer and a cooling pipe
In a 4-liter 4-liter flask, trimellitic anhydride 19
2 g (1 mol) and 600 g of cresol were added and dispersed. To this dispersion was added 99 g (0.5 mol) of 4,4'-diaminodiphenylmethane, and the mixture was reacted at 150 ° C for 3 hours to obtain a dispersion of a divalent carboxylic acid containing an imide group. This dicarboxylic acid was poorly soluble in cresol and turned into a mud at room temperature. Next, after cooling this system to 100 ° C. or lower, 582 g (3 mol) of dimethyl terephthalate and 342 g (1 mol of trimethylene acid triethylene glycol ester)
mol), 93 g (1.5 mol) of ethylene glycol, 186 g (2 mol) of glycerin and 120 g of xylene are added, and the temperature is raised to 200 ° C. over 6 hours while stirring,
Further, the reaction was carried out at this temperature for 5 hours to obtain a polyesterimide resin. At this time, the divalent carboxylic acid containing an imide group was dissolved as the reaction proceeded. Using the polyesterimide resin thus obtained, a polyesterimide insulating paint having a nonvolatile content of 36% and a viscosity of 40 poise was obtained in the same manner as in Example 1, and the insulated wire and the self-insulating wire were prepared from this insulating paint in the same manner as in Example 1. An insulated electric wire having a fusion property was obtained.
The characteristics of this insulated wire and the insulated wire having self-bonding property were examined in the same manner as in Example 1, and the results are also shown in Tables 1 and 2.

Comparative Example 2 As a polyester-imide insulating coating which gives a conventionally peelable, heat-resistant category F insulated wire
Using KS-103J-36M (manufactured by Dainichiseika Kogyo Co., Ltd.), an insulated electric wire and an insulated electric wire having a self-bonding property were obtained by the same method as in Example 1, and then the characteristics were examined and the results are shown in a table. 1, also shown in Table 2.

From the above results, the insulated wire of the present invention has the same characteristics as the conventional product in flexibility, adhesion and heat resistance, and has a solder peelability of 4 at 440 ° C. It is ~ 7 seconds, and it can be seen that the time required for the solder peeling process is considerably shortened. It is also seen that similar results were obtained for an insulated electric wire having a self-bonding property.

[0061]

INDUSTRIAL APPLICABILITY The insulated wire of the present invention is a dihydric alcohol containing an imide group, a precursor thereof or a tetracarboxylic acid or the like which is a raw material thereof, an amino alcohol, a polyhydric alcohol, a polycarboxylic acid and a derivative thereof. An insulating coating is formed on a conductor with an insulating coating material containing a polyester imide resin containing one or both of the above as a constituent component, and the heat-resistant softening temperature is 300 ° C or higher and 440 ° C for 10 seconds or less, and solder peeling treatment is performed. Is possible. Furthermore, in the synthesis of the polyesterimide resin, which is the main component of this raw material insulating paint, the solubility of the raw material was improved by using a dihydric alcohol containing an imide group as the raw material, and as a result, workability during synthesis was improved. . That is, the insulated wire of the present invention is excellent in workability when synthesizing the raw material insulating paint, and further has characteristics such as heat resistance equivalent to those of the conventional product, and the time required for terminal treatment is considerably longer than that of the conventional product. It is useful as a thin wire type insulated electric wire that has been shortened and has heat resistance of class F or higher. In addition, it is also possible to make an insulated wire having a self-fusing property by forming a fusing layer on the polyesterimide insulating film of such an insulated wire.

Claims (3)

[Claims] 1. A compound represented by the general formula (1): (In the formula, R ₁ is a divalent organic group, and R ₂ is ₂ having 2 to 6 carbon atoms.
A valent aliphatic group is shown. ) A dihydric alcohol containing an imide group represented by), a polyhydric alcohol, and a polyesterimide insulating coating containing a polyesterimide resin containing one or both of a polycarboxylic acid and its derivative as a constituent, An insulated wire characterized by having an insulating film formed on the wire. 2. R ₁ in the general formula (1) is represented by the following formula: The insulated wire according to claim 1, which is one or more selected from the group shown in. 3. The insulated wire according to claim 1 or 2, wherein a fusion bonding layer is further formed on the insulating film so as to have a self-fusing property.