JP2003141932A - Resin composition for electric insulation and enamel wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for electric insulation capable of forming a film excellent in adhesion to a conductor, abrasion resistance, and adhesion after thermal degradation while maintaining mechanical characteristics, thermal resistance, flexibility and electric insulation characteristics necessary for an enamel wire, and an enamel wire using the same. SOLUTION: These are the resin composition for electric insulation containing (A) Polyesterimide resin having an isocyanurate ring in a molecular chain, (B) aminothiazole as expressed in either of formula (1) to (6), and (c) polyethersulfone, and the enamel wire coated with the resin composition for electric insulation on a conductor and baked. In the formula, each R expresses independently hydrogen atom or alkyl group having carbon atom number 1 to 4, and Ar is a bivalent aliphatic group in which one carbon atom of the aliphatic ring is bonded to S as expressed in the formula (6) and of which a carbon atom neighboring the carbon atom is bonded to N as expressed in the formula (6).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for electrical insulation and an enamel wire using the same.

[0002]

2. Description of the Related Art Conventionally, polyimid wire, polyamidimid wire and polyesterimid wire are known as insulated wires having heat resistance. Among these, for example, from the viewpoint of balance between characteristics and price, a polyester imid resin in which an imid bond and an isocyanurate ring are introduced into a molecular chain by using tris (2-human oxyethyl) isocyanurate (hereinafter abbreviated as THEIC). A relatively large amount of polyester imidized wire that has been baked is used. On the other hand, in the recent assembly process of electrical equipment, high-speed winding work by machines is performed, and severe stress such as elongation, wear, and bending is applied to the enamel wire, and the degree becomes severer year by year. ing. Therefore, the enameled wire is required to have a high degree of adhesion between the conductor and the coating and wear resistance.
The adhesiveness of the polyester imid varnish using IC was insufficient for the requirement. As means for improving the adhesion between a polyester ester imido varnish using THEIC and a conductor, JP-A-2-58567 and JP-A-7-316425 disclose that a thiol compound is blended with the polyester imido varnish. ing. However, when this method is used, the adhesion between the conductor and the coating is improved, but there is a problem in that the adhesion between the conductor and the coating after the enamel wire is thermally deteriorated is extremely reduced. Further, in the case where the polyester ester imidovarnish using THEIC is blended with only aminothiazole as the component (B) or the polyethersulfone as the component (C) used in the present invention, compared with the case where a thiol compound is blended, Although the adhesion between the conductor and the coating after heat deterioration of the enameled wire is improved, the adhesion between the conductor and the coating before heat deterioration is reduced.

[0003]

DISCLOSURE OF THE INVENTION The present invention, in particular, maintains the various properties such as mechanical properties, heat resistance, flexibility and electrical insulation properties of an enamel wire, and particularly adheres to a conductor, wear resistance and An object of the present invention is to provide an electrical insulating resin composition capable of forming a film having excellent adhesion after heat deterioration and an enamel wire using the same.

[0004]

Means for Solving the Problems The present invention comprises (A) a polyester imid resin having an isocyanurate ring in its molecular chain, and (B) the following general formulas (1) to (6).

[0005]

[Chemical 2]

[In the formula, each R is independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Ar is a carbon atom of an aromatic ring represented by S represented by the general formula (6). Combine,
A carbon atom next to the carbon atom is a divalent aromatic group bonded to N represented by the general formula (6)], and (C) polyether sulfone The present invention provides a resin composition for electrical insulation. The present invention also relates to the aminothiazole (B) based on 100 parts by weight of the polyester imid resin (A).
The present invention provides a resin composition for electrical insulation containing 0.01 to 1 part by weight and 0.1 to 10 parts by weight of the polyether sulfone (C). The present invention also provides an enamel wire obtained by applying the resin composition for electrical insulation onto a conductor and baking the conductor.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester imid resin having an isocyanurate ring in the molecule of the present invention is obtained by the reaction of an acid component and an alcohol component. Here, the isocyanurate ring has the following structure.

[0008]

[Chemical 3]

The polyester imid resin used in the present invention is represented by the general formula (7) as a part of the acid component.

[0010]

[Chemical 4]

[In the formula, R1 means a trivalent organic group such as a residue of tricarbonic acid and R2 means a divalent organic group such as a residue of diamine] preferable. As the imidodicarbonic acid represented by the general formula (7),
For example, imidodicarbonic acid obtained by reacting 2 mol of tricarbonic anhydride with 1 mol of diamine (Japanese Patent Publication No. 51-4011).
No. 3 gazette). Instead of reacting diamine and tricarboic acid anhydride in advance to use as imidodicarboic acid, diamine and tricarboic acid anhydride may be added at the time of production of polyester imid to form a residue of imidodicarboic acid. As tricarbonic anhydride, trimellitic anhydride, 3,4,
There are 4'-benzophenone tricarbonic anhydride, 3,4,4'-biphenyl tricarbonic anhydride and the like, and trimellitic anhydride is preferred. As diamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, m-phenylene diamine, p-phenylene diamine, 1,4-diaminonaphthalene, hexamethylene diamine, diamino diphenyl sulfone and the like are used. The amount of imidodicarboic acid used is preferably in the range of 15 to 65 equivalent% of the total acid components, and more preferably in the range of 20 to 60 equivalent%. If the amount of imidodicarboic acid used is too small, the heat resistance tends to be poor, and if it is too large, the flexibility and the appearance of the enamel wire may deteriorate. As the acid component other than the above imidodicarboic acid, terephthalic acid or a lower alkyl ester thereof, for example, terephthalic acid diester such as monomethyl terephthalate or lower alkyl diester of terephthalic acid, for example, dimethyl terephthalate is used. In addition, compounds that are commonly used in polyester imid varnishes for enameled wires, such as isophthalic acid, adipic acid, phthalic acid, and sebacic acid, can also be used.

As the alcohol component used in the production of a polyester imidate resin having an isocyanurate ring in its molecular chain, those having an isocyanurate ring are preferably used, and tris (human oxymethyl) isocyanurate and tris (2- More preferred are isocyanurate compounds having three hydroxyl groups, such as human oxyethyl) isocyanurate and tris (3-human oxypropyl) isocyanurate, and tris (2-human oxyethyl) isocyanurate is most preferred. The amount of isocyanurate compound used is 30 to 90 equivalent% of all alcohol components.
The range is preferably, and more preferably 40 to 80 equivalent%. If the amount of the isocyanurate compound used is too small, the heat resistance tends to deteriorate, and if it is too large, the flexibility tends to decrease.

Examples of the alcohol component other than the above-mentioned alcohol component having an isocyanurate ring include ethylene glycol, propylene glycol, polyethylene glycol, neopentyl glycol, 1,3-butanediol,
Diols such as 1,4-butanediol and triols such as glycerin, trimethylolpropane and hexanetriol are used. These acid components and alcohol components may be used alone or in combination of two or more. From the viewpoint of flexibility and heat resistance, the mixing ratio of the alcohol component and the acid component is preferably 1.3 to 2.5, more preferably 1.5 to 2.2, in terms of the equivalent ratio of the hydroxyl group to the carboxy group. If the equivalent ratio of the hydroxyl group to the carboxyl group is greater than 2.5, the flexibility tends to decrease,
If it is less than 1.3, the heat resistance tends to decrease. The polyester ester resin used in the present invention can be synthesized, for example, by mixing the above acid component and alcohol component in the presence of an esterification catalyst in the range of 160 to 250.
C., preferably 170 to 250.degree. C., for 3 to 15 hours, preferably 5 to 10 hours.
In this case, examples of the esterification catalyst used include tetrabutyl titanate, lead acetate, dibutylsulaurate, zinc naphthenate, and the like. Further, the reaction is preferably carried out under an inert atmosphere such as nitrogen gas. The imidodicarboic acid may be pre-synthesized, or the imidic acid component of diamine and trimellitic anhydride may be mixed and heated simultaneously with other acid components and alcohol components to effect imidation and esterification. May be performed at the same time. At this time, the blending amount of diamine and trimellitic anhydride is preferably an amount corresponding to the blending amount of the imidodicarbonic acid.

Since the viscosity at the time of synthesis is high, for example,
The synthesis is preferably performed in the coexistence of a phenolic solvent such as phenol, cresol, xylenol.

The aminothiazole used in the present invention is represented by the above general formulas (1) to (6). Specific examples of aminothiazole represented by the general formula (6) include the following compounds.

[0016]

[Chemical 5]

(In the formula, R3 is a hydrogen atom or 1 carbon atom.
To 4 alkyl groups, and n represents an integer of 0 to 4. ) Among the aminothiazoles represented by the general formulas (1) to (6), more specifically preferable compounds include 2-aminothiazol and 2
-Aminobenzazoyl, 2-amino-1,3,4-thiadiazole and the like can be mentioned. As a commercially available product of the polyether sulfone that can be used in the present invention, a trade name PES300P manufactured by Sumitomo Chemical Co., Ltd.
Etc.

The resin composition for electrical insulation of the present invention comprises the above polyester imid resin and aminothiazol and polyether sulfone. The amount of aminothiazol to be blended is preferably 0.01 to 1 part by weight, more preferably 0.05 to 0.8 part by weight, based on 100 parts by weight of the polyester imid resin. If the amount of aminothiazole is less than 0.01 parts by weight, the effect of improving the adhesiveness is small, and if the amount of aminothiazol exceeds 1 part by weight, the adhesiveness after heat-deteriorating the enamel wire tends to decrease.

The blending amount of polyether sulfone is
The amount is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 8 parts by weight, based on 100 parts by weight of the polyester imid resin. If the amount of polyether sulfone is less than 0.1 part by weight, the effect of improving the adhesiveness is small, and if the amount of polyether sulfone exceeds 10 parts by weight, the heat resistance of the enamel wire tends to decrease.

The electrical insulating resin composition of the present invention may further contain a curing agent such as tetrabutyl titanate and an appearance improving agent such as a metal salt of an organic acid such as a zinc salt, a lead salt or a manganese salt, if necessary. It can be added. The amount of the curing agent used is preferably 3 to 10% by weight based on the polyester imid resin, and the amount of the metal salt of the organic acid used is preferably 0.1 to 1% by weight based on the polyester imid resin.

The electrical insulating resin composition of the present invention can be dissolved in a solvent and adjusted to an appropriate viscosity before use.
As the solvent used at this time, for example, a solvent having good solubility with the polyester imid resin such as phenol, cresol, xylenol, cellosolves, and xylene is used.

The thus obtained resin composition for electrical insulation of the present invention is applied to a conductor such as a copper wire and baked to obtain an enamel wire excellent in wear resistance, adhesion and adhesion after heat deterioration. Can be There is no particular limitation on the method for producing the enameled wire, except that the composition of the present invention is used, and a conventional method can be used. For example, a plurality of steps of applying a resin composition for electrical insulation of the present invention on a conductor and heating at 350 to 550 ° C., preferably 400 to 500 ° C. for 1 minute to 5 minutes, preferably 2 to 4 minutes and baking are performed. There may be mentioned a method of forming a film having a desired thickness on the conductor by repeating the process repeatedly. The thickness of the film finally formed is not particularly limited, but is usually preferably 0.02 to 0.08 mm, and more preferably 0.03 to 0.06 mm. The enamel wire of the present invention thus obtained does not deteriorate in various properties such as flexibility.

[0023]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these. In addition, "%" in the examples means "% by weight" unless otherwise specified.

Example 1 (1) Preparation of Polyester Imidide Resin Solution In a four-necked flask equipped with a thermometer, a stirrer and a condenser, 15,4 g (1.6 equivalents) of 4,4′-diaminodiphenylmethane and 307.2 g of trimellitic anhydride were prepared.
(3.2 equivalents), dimethyl terephthalate 232.8g (2.4 equivalents), tris (2-human ethyloxyethyl) isocyanurate 375.8g (4.32 equivalents), ethylene glycol 89.3g
(2.88 eq.), 385 g of cresol and 1.16 g of tetrabutyl titanate were added, and the temperature was raised from room temperature to 170 ° C. in 1 hour in a nitrogen stream.
Reacted for hours. Next, the obtained solution was heated to 215 ° C. and reacted for 6 hours to synthesize a polyester ester. To the obtained resin solution, 920 g of cresol was added, and 41.2 g of tetrabutyl titanate was added.
Was added to obtain a polyester imid resin solution having a nonvolatile content of 42%. (2) Preparation of Resin Composition for Electrical Insulation 100 g of the polyester imid resin solution obtained in (1) above, 0.084 g of 2-aminothiazole (0.2% based on the solid content of the resin solution) and PES
2.1 g (5% based on the solid content of the resin liquid) of 300P (trade name) was added to obtain a resin composition for electrical insulation. The content of tetrabutyl titanate (curing agent) in this electrical insulating resin composition was 4% with respect to the solid content in the polyester imid resin solution.

Example 2 In Example 1 (2), 0.084 g of 2-aminobenzothiazole (0.2% based on the solid content of the resin liquid) was used instead of 2-aminothiazol.
Was carried out according to Example 1 except that was added.

Example 3 In Example 1 (2), 0.084 g of 2-amino-1,3,4-thiadiazole (0.04 g based on the solid content of the resin liquid) was used instead of 2-aminothiazole.
2%) was added, and the procedure of Example 1 was repeated.

Comparative Example 1 The polyester ester imid resin solution of Example 1 (1) was used as it was.

Comparative Example 2 100 g of the polyester imid resin solution obtained in Example 1 (1) was mixed with 5
-Amino-1,3,4-thiadiazole-2-thiol (0.084 g, 0.2% based on the solid content of the resin liquid) was added to obtain a resin composition for electrical insulation.

Comparative Example 3 In Comparative Example 2, 0.084 g of 2-aminothiazole (based on the solid content of the resin solution) was used instead of 5-amino-1,3,4-thiadiazole-2-thiol.
0.2%) was added, and the procedure of Comparative Example 2 was repeated.

Comparative Example 4 In Comparative Example 2, except that 2.1 g of PES300P (5% based on the solid content of the resin liquid) was added instead of 5-amino-1,3,4-thiadiazole-2-thiol. It carried out according to the comparative example 2.

[Test Example] The resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were applied to a copper wire having a diameter of 1.0 mm according to the following baking conditions and baked at a linear speed of 14 m / min to form an enamel wire. It was made.

[Coating / baking conditions] Baking furnace: Hot air type vertical furnace (furnace length 5.5
m) Furnace temperature: Inlet / outlet = 320 ° C / 430 ° C Coating method: Squeeze the enamel wire that has passed through the resin composition with a dice and pass it through the baking furnace 7 times. The diameter of the 1st to 7th dice is 1.05mm, 1.06mm, 1.07mm, 1.08
mm, 1.09mm, 1.10mm, 1.11mm. Further, the adhesion test of the obtained enamel wire was evaluated according to the following method, and other general characteristics (flexibility, thermal shock resistance,
Dielectric breakdown voltage and softening resistance) were measured according to JIS C3003, and the results are shown in Table 1. [Adhesion test] The adhesion is evaluated by a rapid cutting method. That is, both ends of an enamel wire of appropriate length are fixed, the marked line distance is 250 mm, and cutting is performed at a pulling speed of about 4 m / s. At the cutting point, measure the length (mm) of the exposed part of the conductor (2 places),
For example, it is expressed as 1.0 + 1.0. Similarly, the length of the part where the film is separated from the conductor (float of the film) is expressed as 5.0 + 5.0. This is performed at the initial stage of the enamel wire and after deterioration at 200 ° C for 6 hours. In addition, in the adhesion measurement result,
The smaller the value, the better the adhesion between the film and the conductor.

From the results shown in Table 1, the enamel wires produced by using the resin compositions obtained in Examples 1 to 3 have higher wear resistance and adhesion (compared to those obtained in Comparative Example). Early and
It can be seen that it was excellent at 200 ° C / 6 hours) and also had the same properties such as flexibility.

[0032]

[Table 1]

[0033]

INDUSTRIAL APPLICABILITY By using the electrical insulating oil composition containing a poly (ester imidate) having an isocyanurate bond in the molecular chain according to the present invention, wear resistance and adhesion (initial and 200 ° C. /
After 6 hours), an enameled wire is obtained that does not deteriorate properties such as flexibility.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09D 179/08 C09D 179/08 D 181/06 181/06 H01B 7/00 303 H01B 7/00 303 // (C08L 79/08 C08L 81:06 81:06) F-term (reference) 4D075 BB26Z CA02 CA03 CA13 CA18 CA23 DA01 DB06 DC18 EB35 EB37 EB39 EB44 EB56 EC07 EC54 4J002 CM041 CN032 EV316 EV326 GQ01 HA01 4J038 DJ041 KA012 NA032 NA032 PA19 5G305 AA02 AB15 AB34 BA05 CA22 CA35 5G309 CA15

Claims (3)

[Claims] 1. A polyesterimide resin having (A) an isocyanurate ring in its molecular chain, and (B) the following general formulas (1) to (6): [In the formula, each R is independently a hydrogen atom or a carbon atom number 1 to
4 is an alkyl group of 4 and Ar has one carbon atom of an aromatic ring bonded to S represented by the general formula (6), and the carbon atom adjacent to the carbon atom is N represented by the general formula (6). Which is a divalent aromatic group bonded to the above], and a resin composition for electrical insulation containing aminothiazole and (C) polyether sulfone 2. The composition contains 0.01 to 1 part by weight of aminothiazole (B) and 0.1 to 10 parts by weight of polyether sulfone (C) with respect to 100 parts by weight of polyesterimide resin (A). The resin composition for electrical insulation according to claim 1. 3. An enameled wire obtained by applying the resin composition for electrical insulation according to claim 1 or 2 onto a conductor and baking it.