JPH05331367A - Resin composition and insulated wire produced using the same - Google Patents

Abstract

PURPOSE:To obtain a resin compsn. which forms a coating film excellent in appearance even when applied thick and in solderability, heat resistance, and thermal shock resistance by compounding an imidized polyester resin, a stabilized isocyanate, and a polyether sulfone resin. CONSTITUTION:A resin compsn. comprises an imidized polyester resin, a stabilized isocyanate, and a polyether sulfone resin in an amt. of 0.1-10wt.% based on the sum of the two foregoing components. The wt. ratio of the polyester resin to the isocyanate is pref. (1:1)-(1:10) from the viewpoint of the solderability and heat resistance of an insulated wire obtd. by coating a conductor with the compsn. and baking it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition, and more specifically, it produces a coating film which has a good appearance even when the coating film is thick and which is excellent in solderability, heat resistance and thermal shock resistance. The present invention relates to a resin composition and an insulated wire.

[0002]

2. Description of the Related Art Conventionally, as an insulated wire having solderability, a polyurethane insulated wire is known, but its heat resistance is classified into A to E types, and is used for applications requiring heat resistance of B type or more. Had the drawback that it could not be used. Recently, in order to improve this defect, a resin composition containing a polyester resin having an imide group in the molecule and a stabilized isocyanate has been proposed and used for B-type insulation.
However, in this resin composition, although the heat resistance classification is improved to B type, when the coating film is thickly baked, particles are formed in the coating film,
There is a defect that foaming, rough skin, etc. occur and the appearance is inferior.
It is known to add polymer resins such as nylon resin, phenoxy resin, epoxy resin, and polyester resin to improve the appearance of the insulated wire, but even if these resins were added, the coating film was baked thickly. In that case, there is no effect, and if the amount of addition is large, there is a problem that the heat resistance is lowered or the sticking property is poor.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has excellent appearance even when a coating film is thickly baked, and is capable of baking from thin wires to thick wires, and has flexibility, (EN) Provided are a resin composition capable of obtaining an insulated wire excellent in solderability, heat resistance and thermal shock resistance, and an insulated wire using the same.

[0004]

Means for Solving the Problems The present inventors have achieved the above object by using a resin composition containing a polyester resin having an imide bond in the molecule, a stabilized isocyanate compound and a polyethersulfone resin. The present invention has been completed and the present invention has been completed. The present invention includes (a)
A polyester resin having an imide bond in the molecule,
The total amount of the (b) stabilized isocyanate and (c) the polyester resin and the stabilized isocyanate is 0.
The present invention relates to a resin composition containing 5 to 10% by weight of a polyether sulfone resin and an insulated wire formed by applying the resin composition onto a conductor and baking the conductor.

The polyester resin (a) containing an imide bond in the molecule used in the present invention is obtained by the reaction between an acid component and an alcohol component. As a part of the component, the compound of the general formula (I)

[Chemical 1] An imidodicarboxylic acid represented by the formula (R in the formula means a divalent organic group) is used. The imidodicarboxylic acid represented by the general formula (I) is, for example, JP-B-51-40.
As disclosed in Japanese Patent No. 113, it is obtained by reacting 2 mol of trimellitic anhydride with 1 mol of diamine. Examples of the diamine include 4,4 ′
-Diaminodiphenylmethane, m-phenylenediamine, p-phenylenediamine, 1,4-diaminonaphthalene, 4,4'-diaminodiphenyl ether, hexamethylenediamine, diaminodiphenylsulfone and the like. In the present invention, diisocyanates corresponding to the above diamines may be used instead of these diamines. From the viewpoint of solderability, heat resistance and thermal shock resistance of the final composition, the amount of the imidodicarboxylic acid represented by the general formula (I) is preferably in the range of 10 to 30 equivalent%.

Examples of the acid component other than the imidodicarboxylic acid used in the polyester resin having an imide bond in the molecule include terephthalic acid or its lower alkyl ester such as dimethyl terephthalate, monomethyl terephthalate, and diester terephthalate. Be done. Also,
Compounds commonly used in polyester varnish for enameled wire,
For example, isophthalic acid, adipic acid, phthalic acid, sebacic acid, etc. can be used.

The alcohol component of the polyester resin having an imide bond in the molecule is, for example, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, neopentyl glycol, 1 Examples include diols such as 1,3-butanediol and 1,4-butanediol, triols such as glycerin, trimethylolpropane, hexanetriol, and tris- (2-hydroxyethyl) isocyanurate. These acid components and alcohol components may be used alone or in combination of two or more. It is preferable to react all the alcohol components in excess with respect to the total acid components in an equivalent amount. This is because the hydroxyl group remains in the molecular chain of the polyester resin having an imide bond in the molecule, and this reacts with the stabilized isocyanate during baking to form a urethane bond. From the viewpoint of solderability and heat resistance, the equivalent ratio of total alcohol component / total acid component is preferably 1.2 to 2.5, more preferably 1.4 to 2.4.

The polyester resin (a) having an imide bond in the molecule is synthesized by mixing the above acid component and alcohol component in the presence of an esterification catalyst at 170 ° C. to 250 ° C.
It is carried out by heating at a temperature of ° C. Examples of the esterification catalyst used at this time include tetrabutyl titanate, lead acetate, dibutyltin laurate, zinc octenoate, zinc naphthenate and the like. The imidodicarboxylic acid may be a pre-synthesized one, and a component such as a diamine and trimellitic anhydride that becomes an imidic acid is mixed with another acid component and an alcohol component and heated at the same time for imidization and esterification. The conversion may be performed at the same time. The polyester resin having an imide bond in the molecule is preferably synthesized in the coexistence of a phenolic solvent such as phenol, cresol, xylenol or the like because the viscosity at the time of synthesis is high.

The stabilized isocyanate (b) used in the present invention is a compound obtained from 4,4'-diphenylmethane diisocyanate and xylenol (Millionate MS-50 manufactured by Nippon Polyurethane Industry Co., Ltd.), 4,
Compound obtained from 4'-diphenylmethane diisocyanate, aliphatic polyol and phenols (Coronate 2503 manufactured by Nippon Polyurethane Industry Co., Ltd.), compound obtained from tolylene diisocyanate, aliphatic polyol and phenols (Dismodular AP Stable manufactured by Bayer) , 4,4′-diphenylmethane diisocyanate and tolylene diisocyanate are added with tris (2hydroxyethyl) isocyanurate, and the free isocyanate group is blocked with phenols to obtain a blocked isocyanate resin.

The mixing ratio of the polyester resin (a) having an imide bond in the molecule and the stabilizing isocyanate (b) is 100% from the viewpoint of solderability and heat resistance of the insulated wire. The amount of the stabilized isocyanate (b) is preferably 100 to 1000 parts by weight, more preferably 150 to 500 parts by weight, based on parts by weight.

The polyether sulfone resin used in the present invention is

[Chemical 2] A resin having a molecular structure of (where n is a positive integer). Commercially available products are PES5003P, 4100G, 4800.
G, 3600G and 5200G (all are trade names manufactured by Mitsui Toatsu Chemicals, Inc.).

The resin composition of the present invention contains a polyether sulfone resin in an amount of 0.5 to 10% by weight based on the total amount of the polyester resin (a) having an imide bond in the molecule and the stabilized isocyanate (b). More preferably 1.0-5.
It is obtained by blending in an amount of 0% by weight. If the addition amount of the polyether sulfone resin exceeds 10% by weight, the heat resistance is lowered, and if it is less than 0.5% by weight, the flexibility and the appearance of the baked wire are not improved.

The resin composition of the present invention may optionally be added with an organometallic compound, dissolved in a solvent, and applied directly or together with another insulating coating film on a conductor by a conventional method and baked to form an insulated wire. It Examples of the organometallic compound include metal salts of zinc, lead, manganese, tin, and the like of aliphatic carboxylic acids, which improve the linear velocity at the time of baking an insulated wire, shorten the curing time, lower the curing temperature, and Effective in improving solderability. Further, as the solvent, for example, phenol,
Cresol, xylenol, cellosolves, carbitols, xylene and the like are used.

[0014]

EXAMPLES Next, the present invention will be described in more detail by way of examples. In addition,% in the following examples means weight%. Example 1 In a four-necked flask equipped with a thermometer, a stirrer and a condenser,
4,4'-Diaminodiphenylmethane 99g (1.0 equivalent), trimellitic anhydride 192g (2.0 equivalent), dimethyl terephthalate 291g (3.0 equivalent), ethylene glycol 93g (3.0 equivalent), glycerin 92g
(3.0 equivalents), 217 g of cresol and 3.8 g of tetrabutyl titanate were added, and the temperature was raised to 170 ° C. in a nitrogen stream to react for 60 minutes. The resulting solution is then added to 2
The temperature was raised to 10 ° C. and the reaction was carried out for 3 hours. Further, 436 g of cresol was added to this solution to obtain a polyester resin solution having a nonvolatile content of 50% and having an imide bond in the molecule.
125 g of Coronate 2503 (stabilized isocyanate compound manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to 100 g of a polyester resin solution having an imide bond in the obtained molecule.
1.75 g (1.0% by weight) of PES5003P (polyether sulfone resin manufactured by Mitsui Toatsu Chemicals, Inc.), cresol 2
10 g, xylene 55 g and zinc naphthenate 1.5 g were added to obtain a resin composition of the present invention.

Example 2 100 g of a polyester resin solution having an imide bond in the molecule obtained in Example 1 was added to Coronate 2503 12
5 g, PES5003P 8.75 g (5.0% by weight), cresol 210 g, xylene 55 g and zinc naphthenate 1.5 g were added to obtain a resin composition of the present invention.

Example 3 To 100 g of the resin solution having an imide bond in the molecule obtained in Example 1, 125 g of Coronate 2503 and PES were added.
5003P 17.5 g (10% by weight), cresol 2
10 g, xylene 55 g and zinc naphthenate 1.5 g were added to obtain a resin composition of the present invention.

Comparative Example 1 100 g of the polyester resin solution having an imide bond in the molecule obtained in Example 1 was added to Coronate 25031.
A resin composition was obtained by adding 25 g, 210 g of cresol, 50 g of xylene and 1.5 g of zinc naphthenate.

Comparative Example 2 A general-purpose polyurethane insulated wire varnish WD-437 (manufactured by Hitachi Chemical Co., Ltd.) is used as Comparative Example 2.

The following tests were conducted using the resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2. Test Example (1) Appearance Evaluation of Insulated Electric Wire A copper wire having a diameter of 0.07 mm was baked under the following conditions while changing the coating thickness, and the appearance was visually observed. The results are shown in Table 1. The baking conditions are as follows. Baking furnace: Horizontal furnace Furnace temperature: Inlet / outlet = 330 ° C / 380 ° C Linear velocity: 240m / min Coating method: Felt 7 times drawing

[0020]

[Table 1]

From the results shown in Table 1, the resin composition of the present invention has a better appearance than that of the comparative example, and it is possible to obtain a film twice as thick under the same conditions.

(2) Special evaluation of insulated electric wire Various special products were evaluated by baking on a copper wire having a diameter of 1.0 mm. The results are shown in Table 2. The baking conditions are as follows. Baking furnace: Solid furnace Temperature of furnace: Inlet / outlet = 330 ° C./380° C. Linear velocity: 18 m / min Coating method: Die 7 times drawing The test items in Table 2 are JIS C3003 5
It measured according to -19. Regarding the dielectric breakdown voltage after thermal deterioration, the twisted wire prepared according to JIS C3003 was left in a constant temperature bath at 200 ° C. for 168 hours, and then the dielectric breakdown voltage was measured.

[0023]

[Table 2]

From the results shown in Table 2, when the resin composition of the present invention is used, the appearance, flexibility, thermal shock resistance, and insulation after heat deterioration are compared with the case of the conventional general-purpose polyurethane insulated wire. It is shown that the retention of the breakdown voltage and the softening resistance are excellent, and the appearance and flexibility are excellent as compared with the conventional heat-resistant urethane wire of Comparative Example 1.

[0025]

When the resin composition of the present invention is used, the appearance is good even when the coating film is thick, and the flexibility is excellent, and the solderability, heat resistance and thermal shock resistance are also excellent. An insulated wire can be manufactured.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H01B 3/30 E 9059-5G 7/02 Z 8936-5G // H01B 7/34 A 7244-5G

Claims (2)

[Claims] 1. 0.5 to 10% by weight based on the total amount of (a) a polyester resin having an imide bond in the molecule, (b) a stabilized isocyanate, and (c) the polyester resin and a stabilized isocyanate. A resin composition containing the polyether sulfone resin of. 2. An insulated electric wire obtained by applying and baking the resin composition according to claim 1 on a conductor.