JP2510828B2 - Insulated wire for soldering - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated electric wire for soldering, which is used in a portion of a winding for electronic equipment or the like that requires soldering and which has excellent heat resistance.

[0002]

2. Description of the Related Art Conventionally, a polyurethane insulated wire has been widely used as an insulated wire used in a portion such as a winding for electronic equipment which requires soldering. This is because the polyurethane insulating layer is melted and decomposed by heat, so that the insulating layer can be soldered as it is without peeling. However, in recent years, the miniaturization and high performance of electronic devices have progressed, and along with this, the applications for functioning in a high temperature atmosphere are also expanding, and of course various used parts in providing such applications. High heat resistance is required, but there are many applications in which conventional general-purpose polyurethane insulated wires for soldering can no longer cope with heat resistance.

Therefore, as an insulated wire for soldering replacing the above polyurethane insulated wire, a modified polyester insulated wire and a modified polyesterimide insulated wire, which can be soldered without peeling the insulating layer, have been developed, and have already been used for some applications. in use.

However, even these modified polyester insulated wires and modified polyesterimide insulated wires cannot sufficiently cope with the recent widespread application of electronic equipment to high temperature application fields, and further have high heat resistance, and With regard to solderability as well, there is a strong demand for the development of an insulated wire in which the insulation layer is rapidly decomposed and which has good operability.

[0005]

Means for Solving the Problems As a result of intensive studies to address the above-mentioned demand, the present inventors have found that when a polyamide-imide coating composed of specific constituents is used for forming an insulating layer, Has excellent heat resistance, the insulation layer decomposes rapidly during soldering, and the operability of assembly is excellent. It is sufficient as a winding wire used for the soldering part of electronic devices used under high temperature these days. The present invention has been achieved by finding that an applicable insulated wire can be provided and that both the heat resistance and the solderability can be adjusted according to the application of the insulated wire.

That is, the insulated wire for soldering according to claim 1 of the present invention comprises trimellitic anhydride and 0.5 to 2 mol of aliphatic dicarboxylic acid per 1 mol of trimellitic anhydride. It employs a structure having an insulating layer formed by coating and baking a polyamideimide coating obtained by reacting both components with a diisocyanate compound in an approximately equimolar amount.

[0007]

Detailed structure and function of the invention Polyamideimide of the coating material for forming an insulating layer according to the present invention is different from general polyamideimide using trimellitic anhydride and diamine as reaction components, and is different from trimellitic anhydride and aliphatic dicarboxylic acid. Is obtained by reacting with a diisocyanate compound, an imide bond by the reaction of an acid anhydride structure of trimellitic anhydride and an isocyanate group in the main chain, and a carboxyl group of trimellitic anhydride and an aliphatic dicarboxylic acid. It has an amide bond by the reaction of an isocyanate group with. However, the reason why an insulated wire having an insulating layer obtained by applying and baking such a polyamide-imide coating exhibits excellent heat resistance and solderability is not clear, but as described later, it is not possible to use anhydrous trihydrate. Since the heat resistance and solderability can be controlled by the ratio of the use of meritic acid and aliphatic dicarboxylic acid, the aromatic polyimide structure based on trimellitic anhydride contributes greatly to heat resistance. It is considered that the aliphatic polyamide structure based on the aliphatic dicarboxylic acid greatly contributes to the thermal decomposability in.

To prepare the above polyamide-imide coating, trimellitic anhydride, an aliphatic dicarboxylic acid and a diisocyanate compound may be dissolved in a suitable solvent and heated to react with each other. In the above, the diisocyanate compound needs to be approximately equimolar to the total number of moles of trimellitic anhydride and aliphatic dicarboxylic acid, and if this molar ratio greatly deviates from equimolar amounts, good polyamideimide cannot be produced. . Also,
A polyamide-imide coating obtained by using an aromatic dicarboxylic acid instead of an aliphatic dicarboxylic acid is not preferable because the insulated wire produced using this will have poor solderability.

The aliphatic dicarboxylic acid used in the synthesis of the polyamideimide is not particularly limited as long as it is a saturated dicarboxylic acid, but the carbon of the alkylene group such as succinic acid, adipic acid, araisenic acid, sebacic acid and dodecanedioic acid is used. It is preferable that the number is two or more, and these may be used in combination of two or more.

Examples of the diisocyanate compound include toluene diisocyanate, hexamethylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 1,5-naphthalenediisocyanate, and the like. The above can be used together.

The proportion of trimellitic anhydride and aliphatic dicarboxylic acid used is in the range of 0.5 to 2 mol of aliphatic dicarboxylic acid per 1 mol of trimellitic anhydride, and the ratio of trimellitic anhydride is If it is too small, the heat resistance of the insulated electric wire for soldering is lowered, and conversely, if the proportion of the aliphatic dicarboxylic acid is too small, the solderability of the insulated electric wire becomes insufficient. However, as an insulated wire, if particularly high heat resistance is required, the proportion of trimellitic anhydride used may be set to be large within the above range. The use ratio of dicarboxylic acid may be set large within the above range. That is, in the insulated wire for soldering of the present invention, by changing the use ratio of trimellitic anhydride and aliphatic dicarboxylic acid in the polyamide-imide coating for forming an insulating layer, both heat resistance and solderability are in a high range. Easy to control as required.

In order to manufacture the insulated wire for soldering of the present invention, the above polyamide-imide coating is adjusted in viscosity by adding an appropriate diluting solvent, if necessary, and then applied on a conductor such as annealed copper wire according to a conventional method. The insulating layer may be formed by coating and baking. Although the thickness of the insulating layer varies depending on the diameter of the conductor, it is generally about 5 to 50 μm, and is usually set to the required thickness by repeating the coating and baking a plurality of times.

[0013]

EXAMPLES Example 1 1 mol of trimellitic anhydride, 1 mol of adipic acid, and 4
・ 2 mol of 4'-diphenylmethane diisocyanate is added to N
-Methyl-2-pyrrolidone was added to 1 at 100 ° C.
After reacting at 120 ° C. for 2 hours, 14
The temperature was raised to 0 ° C over 1 hour, and at this temperature, 1 more
After reacting for a period of time and cooling, xylene was added for dilution to prepare a polyamide-imide coating. This paint 0.50mm
16μ thick after being coated and baked multiple times on the surface of annealed copper wire with a diameter of
An insulated electric wire for soldering having an insulating layer of m was manufactured.

Example 2 An insulated wire for soldering was produced in the same manner as in Example 1 except that 1 mol of araisenic acid was used instead of adipic acid.

Example 3 An insulated electric wire for soldering was produced in the same manner as in Example 1 except that the amount of trimellitic anhydride used was changed to 1.2 mol and the amount of adipic acid used was changed to 0.8 mol. did.

Example 4 An insulated wire for soldering was manufactured in the same manner as in Example 1 except that the amount of trimellitic anhydride used was changed to 0.8 mol and the amount of adipic acid used was changed to 1.2 mol. did.

Comparative Example 1 An insulated wire was manufactured in the same manner as in Example 1 except that the amount of trimellitic anhydride used was changed to 1.4 mol and the amount of adipic acid used was changed to 0.6 mol.

Comparative Example 2 An insulated wire was manufactured in the same manner as in Example 1 except that the amount of trimellitic anhydride used was changed to 0.6 mol and the amount of adipic acid used was changed to 1.4 mol.

Comparative Example 3 Insulated wire having a 16 μm thick insulating layer in the same manner as in Example 1 except that a modified polyesterimide paint (trade name FS-2 manufactured by Dainichiseika Co., Ltd.) was used in place of the polyamideimide paint. Was manufactured.

Comparative Example 4 A modified polyester paint (TBS-100 manufactured by Tokushu Paint Co., Ltd.) was used in place of the polyamide-imide insulating paint.
An insulated wire having an insulating layer having a thickness of 16 μm was manufactured in the same manner as in Example 1.

With respect to the insulated wires of the above Examples and Comparative Examples, the appearance, flexibility, adhesion, insulation layer pinholes, dielectric breakdown voltage, softening temperature, thermal shock resistance, solderability, chemical resistance Each of the abrasion resistance tests was performed. The results are shown in the following Table 1 together with the application test method for each item.

Table 1

From the results in the above table, the soldered insulated electric wires of the present invention (Examples 1 to 4) are the conventional solderable modified polyesterimide insulated electric wires (Comparative Example 3) and modified polyester insulated electric wires (Comparative Example). It is clear that it has much higher heat resistance than that of 4), is excellent in solderability, and can satisfy various performances required for other insulated wires. Further, from the comparison between Examples 1 to 4 and Comparative Examples 1 and 2, the molar ratio of trimellitic anhydride: aliphatic dicarboxylic acid, which is a constituent component of the polyamideimide coating used for forming the insulating layer, is 1: 0.5 to 2 From the fact that an insulated electric wire for soldering that satisfies both heat resistance and solderability to a high degree can be obtained when the content is within the range of, and further, comparison between Example 1 and Examples 3 and 4, shows that the moles of both constituent components are It can be seen that by changing the ratio within the above range, both the heat resistance and the solderability can be freely controlled in a high range.

[0024]

According to the present invention, the insulated wire for soldering has extremely high heat resistance and excellent solderability,
It can be applied well to the winding of the electronic parts used in recent high temperature where soldering is required, and moreover, both the heat resistance and the solderability can be easily controlled in a high range. Things will be provided.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhisa Ishimoto 2-19-1 Inadera, Amagasaki City, Hyogo Prefecture Daiichi Denko Co., Ltd. Technical Department (72) Makoto Tai 2-19-1 Inadera, Amagasaki City, Hyogo Prefecture (56) Reference JP-A-50-67331 (JP, A) JP-A-2-117957 (JP, A)

Claims (1)

(57) [Claims] 1. Trimellitic anhydride and this trimeric anhydride
Insulating layer formed by applying and baking a polyamideimide coating obtained by reacting 0.5 to 2 moles of aliphatic dicarboxylic acid with respect to 1 mole of ritic acid and approximately equimolar amounts of diisocyanate compound with respect to both components. Insulated electric wire for soldering .