JP3364372B2 - Insulated wire - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an insulated wire having excellent solderability and heat resistance.

[0002]

Conventionally, as an insulated wire that can be directly soldered without peeling off the insulating film,
Polyurethane insulated wire is widely used. However, in recent years, with the miniaturization and high performance of electric devices, the operating ambient temperature of the devices often rises,
Heat resistance of insulated wires, which is a material used for electric equipment, is required. Therefore, the conventional polyurethane insulated wire has come to be used in applications that cannot satisfy the heat resistance requirement. On the other hand, an insulated wire that can be soldered without peeling off the insulating film is desired, as in the case of the polyurethane insulated wire, because of the ease of end treatment of the insulated wire.

As a substitute for the above-mentioned polyurethane insulated wire, polyesterimide insulated wire or polyesterimide urethane insulated wire which can be soldered without peeling off the insulating film has been developed and used for some applications. Although imide-insulated wires have sufficient heat resistance, their solderability is significantly inferior to polyurethane-insulated wires.
Polyester imide urethane insulated electric wire can almost satisfy the solderability, but does not sufficiently satisfy the demand for heat resistance. Therefore, development of an insulated wire having both solderability and heat resistance is strongly required.

[0004]

Means for Solving the Problems As a result of extensive studies on the above problems, the present inventor has found that polyhydric alcohols and anhydrous trimellitic acid
Urethane bond in the molecule, which is obtained by reacting polyamic acid with formic acid and / or pyrimellitic anhydride .
The inventors have found that an insulated wire having an insulating layer obtained by applying and baking an insulating coating material containing a resin having an amide bond and an imide bond on a conductor is obtained, and the present invention has been accomplished.

By using an insulating coating material containing a specific resin, an insulated wire having excellent solderability and heat resistance is provided.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to embodiments of the invention. The insulating coating used in the present invention has a polyhydric alcohol of 20 to 45 mol% and a polycarboxylic acid or its derivative of 30 to 5 mol%, and a ratio of 0.8 to 1.10. It is an insulating coating material containing a resin obtained by reacting a polyisocyanate of which mol% is The ethylene glycol as a polyhydric alcohol, polycarboxylic acid or trimellitic anhydride and / or pyromellitic anhydride benefits acids as derivatives thereof, and diphenylmethane diisocyanate are preferred as polyisocyanates.

[0007] Paint used in the present invention are those obtained by reacting a diphenylmethane diisocyanate and ethylene glycol and trimellitic acid and / or pyromellitic anhydride benefits anhydride, urethane between the isocyanate group and the alcohol group coupling the carboxyl group of an imide bond, and further isocyanate groups and trimellitic anhydride and / or pyromellitic anhydride benefits acids between the acid anhydride structure of the isocyanate groups and trimellitic anhydride and / or pyromellitic anhydride benefits acid It is considered to have an amide bond between and.

The insulated wire having an insulating layer formed by coating and baking the coating material used in the present invention exhibits excellent solderability due to the presence of urethane bonds, and excellent heat resistance due to the presence of imide bonds and amide bonds. It is considered to be a thing. In order to prepare the above-mentioned insulating paint, first, in a suitable solvent, diphenylmethane diisocyanate and ethylene glycol are reacted at room temperature, and then trimellitic anhydride and / or pyrolitic anhydride are added and reacted by heating. Just do it.

[0009] As another method for obtaining a paint, diphenylmethane diisocyanate and ethylene glycol, and after batch mixing trimellitic anhydride and / or pyromellitic anhydride benefits acid at room temperature, may be heated and reacted. Diphenylmethane diisocyanate and trimellitic anhydride and /
Or after heating the reaction of pyromellitic anhydride benefits acids, it is also possible to react the ethylene glycol.

It is also possible to replace a part of ethylene glycol with other polyols such as glycerin, trimethylolpropane, tris (2-hydroxyethyl) isocyanurate (THEIC), etc. within a range not impairing the object of the present invention. Is.

It is also possible to replace a part of trimellitic anhydride with another polycarboxylic acid, for example, an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid, phthalic anhydride, etc. within a range not impairing the object of the present invention. It is possible.

The solvent used in the insulating coating material used in the present invention is preferably NMP, DMAC, DMF or the like, which is a solvent, in combination with a diluent such as xylene or solvent naphtha, but phenols, cresols, glycol ethers are preferred. Solvents used in ordinary baking paints such as alcohols, alcohols and ketones may be used or partly added.

The insulating coating material used in the present invention is a thermoplastic resin such as polyamide, polyester, polysulfone, polyvinyl formal, or epoxy, polyester, polyester imide, as long as the characteristics of the present invention are not impaired.
Stabilized polyisocyanate compounds obtained from thermosetting resins such as polyurethane, polyamide imide, melamine resin, phenol resin, etc., polyisocyanates such as diphenylmethane diisocyanate, dyes, pigments, lubricants, and other additives for paints may also be added. It is possible. Also,
If necessary, metal salts of naphthenic acid and octenoic acid, amines such as alkylamines and imidazoles, and organic tin compounds can be added as catalysts.

In order to produce the insulated wire of the present invention, the above-mentioned paint is adjusted with a suitable solvent to a viscosity suitable for work, and then coated and baked on a conductor such as annealed copper wire according to a conventional method to form an insulating layer. To do.

Further, the insulated wire of the present invention is coated with the above-mentioned paint, and is coated with another insulating paint, as is generally done in order to give various characteristics to the upper layer of the insulating layer. It is also possible to provide a baked insulating layer. For example, when heat resistance is further required, polyimide-based insulating paint or polyamide-imide-based paint, when winding property is required, polyamide-based paint such as 6,6-nylon, coil shape self-holding is required. If so, there are self-fusing coatings such as polyvinyl butyral, epoxy, phenoxy, polyester, polyamide, polysulfone based coatings.

[0016]

The contents of the present invention will be described in the following examples, but the present invention is not limited to these examples. Example 1 2.0 mol of ethylene glycol and 3.0 mol of trimellitic anhydride were mixed with N-methyl-2-pyrrolidone (hereinafter referred to as NMP).
(Hereinafter abbreviated as)) at room temperature for 0.5 hours,
The insulating coating obtained by adding 4.8 mol of diphenylmethane diisocyanate and heating and reacting at 120 ° C. for 3 hours is baked on a 0.2 mm soft copper wire according to a conventional method so that the film thickness becomes 0.015 mm, Got

Example 2 3.0 mol of ethylene glycol and 2.0 mol of trimellitic anhydride were reacted in NMP at room temperature for 0.5 hours, and then 4.8 mol of diphenylmethane diisocyanate was added and heated to 120. The insulating paint obtained by reacting at 3 ° C. for 3 hours was baked in the same manner as in Example 1 to obtain an insulated electric wire.

Example 3 4.0 mol of ethylene glycol and 1.0 mol of trimellitic anhydride were reacted in NMP at room temperature for 0.5 hour, and then 4.8 mol of diphenylmethane diisocyanate was added and heated to 120. The insulating paint obtained by reacting at 3 ° C. for 3 hours was baked in the same manner as in Example 1 to obtain an insulated electric wire.

Comparative Example 1 1.0 mol of ethylene glycol and 4.0 mol of trimellitic anhydride were reacted in NMP at room temperature for 0.5 hours, and then 4.8 mol of diphenylmethane diisocyanate was added and heated to 120. The insulating paint obtained by reacting at 3 ° C. for 3 hours was baked in the same manner as in Example 1 to obtain an insulated electric wire.

Comparative Example 2 An insulated electric wire was obtained in the same manner as in Example 1 by using a solderable polyester imide paint (trade name: FS-2 manufactured by our company).

Comparative Example 3 Polyesterimide urethane paint (trade name FS- manufactured by our company)
An insulated wire was obtained in the same manner as in Example 1 by using 141).

With respect to each of the insulated wires of the above Examples and Comparative Examples, the results of the appearance, flexibility, extension pinhole property, softening point, dielectric breakdown voltage, thermal shock resistance, and solderability tests were given. The results are shown in Table 1. The test method is JIS C
It was measured according to 3003.

Table 1 Note 1) Dielectric breakdown voltage residual rate 220 ° C 7 days after degrading dielectric breakdown voltage to the initial value Note 2) Thermal shock resistance 20% extension 220 ° C 1 hour Note 3) Solderability Solder bath temperature 400 ° C Comparative Example 1 is 460 ° C

From the results shown in Table 1, the insulated wire of the present invention shows extremely good solderability as compared with the conventional solderable polyesterimide insulated wire. Further, it has excellent heat resistance to the polyester-imide-urethane insulated electric wire, although it has the same solderability.

[0025]

INDUSTRIAL APPLICABILITY The insulated wire according to the present invention has excellent solderability and high heat resistance, and can sufficiently meet the characteristic requirements for the insulated wire used in recent electronic devices.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiki Yamada 1-7-6 Nihonbashi Bakuro-cho, Chuo-ku, Tokyo Dainichi Seika Kogyo Co., Ltd. (56) Reference JP-A-2-87607 (JP, A) Special Features Kaihei 8-264027 (JP, A) JP-A-4-85378 (JP, A) JP-B 4-69402 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01B 7 / 02 H01B 3/30

Claims (5)

(57) [Claims] 1. A polyhydric alcohol and trimellitic anhydride and
And / or pyrimellitic anhydride and polyisocyanate are reacted to obtain a urethane bond or an amide bond in the molecule.
An insulated wire having an insulating layer formed by applying and baking an insulating coating material containing a resin having an amide bond and a resin on a conductor. 2. The insulating paint is polyhydric alcohol 20-45.
Mol% and polyvalent carboxylic acid or its derivative 30 to 5 mol%, and 0.8 to 1.
The insulated wire according to claim 1, which is an insulating coating material containing a resin obtained by reacting a polyisocyanate in a mole ratio of 10. Wherein the polyhydric alcohol is ethylene glycol, insulated wire according to claim 1 or 2 port polyisocyanate is diphenylmethane diisocyanate. 4. The insulated wire according to claim 3, wherein a part of ethylene glycol is replaced with glycerin, trimethylolpropane or tris (2-hydroxyethyl) isocyanurate. 5. The insulated wire according to claim 3, wherein a part of trimellitic anhydride is replaced with an aromatic dicarboxylic acid.