JP3337084B2 - Resin composition for electrical insulation and enameled wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition for electrical insulation and an enameled wire.

[Prior art]

Conventionally, insulated wires (hereinafter abbreviated as enameled wires) obtained by applying and baking a synthetic resin paint such as polyvinyl formal, polyurethane, polyester, polyester imide or polyamide imide on a conductor are characterized by the characteristics of each paint. They are used for various applications such as motors and transformers. In recent years, electric manufacturers that use enameled wires have introduced automatic high-speed winding machines to streamline the manufacturing process of their equipment. There is a problem that mechanical damage is caused in the layer, and layer short-circuiting, grounding failure, and the like occur, thereby increasing the product failure rate. Therefore, there is a demand for an enameled wire with less mechanical damage and excellent lubricity.

[0003] Normally, enameled wire alone has poor lubricity, so liquid paraffin, solid paraffin, insulating oil, wax or the like is applied to the enameled wire, or nylon or the like having excellent mechanical strength and wear resistance is overcoated. The method is adopted. However, in the former method, there is a problem that poor affinity for adhesives and voids are liable to occur because the affinity of the enamel wire after winding the motor or transformer onto the impregnated or injected vanil or resin is poor. Also, in the latter method, since the baking wire cannot be baked under the same conditions (furnace temperature, baking speed, etc.) as the baking wire of the undercoat enameled wire, the productivity is reduced, and the enameled wire characteristics such as the cut-through temperature are reduced. However, the price is high and the range of use has been limited.

Recently, a method of dispersing wax or low-molecular-weight polyethylene in a synthetic resin paint for undercoat of enameled wire and overcoating the same under the same conditions as the paint for undercoat has been studied. Since the molecular weight polyethylene is poor in compatibility with the enamel wire synthetic resin and the solvent, it is difficult to disperse in the enamel wire synthetic resin paint.For example, even if it is forcibly dispersed by a method such as vigorous stirring, it is separated. In addition, the enamel wire had poor appearance and poor slipperiness due to the poor degree of dispersion, and had poor drawbacks in the range where the baking temperature of the enamel wire was high.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned disadvantages of the prior art, and has good dispersibility of a lubricant, excellent appearance of an enameled wire, and excellent slipperiness even in a wide range of baking conditions. An object of the present invention is to provide an obtained resin composition for electrical insulation and an enameled wire using the same.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above problems, and as a result, further added a metal salt to an electrically insulating resin composition containing a partially saponified ester wax and low molecular weight polyethylene. By doing so, the dispersibility of the lubricant and the appearance of the enameled wire are good and the slipperiness is improved even in a range where the baking conditions of the enameled wire are high (for example, a high baking temperature side and a low baking speed side). And arrived at the present invention. That is, the present invention is, Polya
(A) 0.1 to 10 parts by weight of partially saponified ester wax, and (B) number average molecular weight of 500 with respect to 100 parts by weight of the resin component of the synthetic resin paint for electrical insulation containing midimide as a resin.
0 to 10 parts by weight of low molecular weight polyethylene and copper (C) , manganese or cobalt as a metal component.
The present invention relates to an electrically insulating resin composition comprising 0.0001 to 1 part by weight of a metal salt, and an enameled wire obtained by coating and baking the composition directly or via another insulating material on a conductor.

The synthetic resin coating for electrical insulation used in the present invention is not particularly limited. For example, polyvinyl formal,
A coating containing a resin such as polyurethane, polyester, polyester imide, polyamide imide, or polyimide is used. Among these, polyamide imide resin is an essential component because it has a large effect of imparting lubricity to baked enameled wires with higher baking conditions. Used as

The partially saponified ester wax (A) used in the present invention includes, for example,

Embedded image (Wherein, R and R 'each represent a hydrocarbon group having 28 to 32 carbon atoms, and R and R' may be the same) and derivatives thereof. Examples of commercially available products include Hoechst Wax OP and Hoechst Wax X.
55, Hoechst Wax OM, Hoechst Wax OM, and Hoechst Wax FL (all are trade names manufactured by Hoechst Japan Ltd.). Partially saponified ester waxes are used because of their excellent compatibility with low molecular weight polyethylene (B). The amount of the partially saponified ester wax (A) used is 0.1 to 10 with respect to 100 parts by weight of the resin component of the paint.
Parts by weight, preferably 0.2 to 5 parts by weight. If the amount is less than 0.1 part by weight, the effect of the slipperiness is inferior, and if it exceeds 10 parts by weight, the appearance of the enameled wire is inferior.

Low molecular weight polyethylene used in the present invention
(B) is not particularly limited as long as it has a number average molecular weight of 5,000 or less, preferably 1,000 to 4,000.
If the number average molecular weight exceeds 5,000, the dispersibility is poor, and the appearance of the enameled wire is reduced. Commercially available products include, for example, Hoechstwax PE520 and Hoechstwax PE1
30 (both are trade names manufactured by Hoechst Japan Co., Ltd.). The amount of the low molecular weight polyethylene used is 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on 100 parts by weight of the resin component of the paint. When the amount is less than 0.1 part by weight, the effect of improving the slipperiness is not obtained. When the amount exceeds 10 parts by weight, the appearance of the enameled wire is reduced, and the composition undergoes layer separation in a short time. When the above component (A) or component (B) is blended alone, the dispersion in the paint becomes uneven and the appearance of the enamel wire is reduced,
Further, the composition undergoes phase separation in a short time.

The metal salt (C) used in the present invention prevents thermal deterioration of the coating film surface during baking of a synthetic resin paint for electrical insulation, especially an amide-imide resin paint, and improves the slipperiness of the obtained enameled wire. Let it. As the metal component of the metal salt, copper, manganese or cobalt is used as the salts thereof,
Examples include copper acetate, copper salicylate, copper stearate, copper (II) chloride, manganese lactate, manganese acetate, manganese salicylate, cobalt acetate, cobalt naphthenate, cobalt octylate, and the like, and mixtures thereof. These metal salts include phenolic anti-aging agents such as 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester and amine-based aging agents such as N, N'-di-2-naphthyl-P-phenylenediamine. It can also be used with inhibitors. The amount of the metal salt to be added is 0.0001 to 1 part by weight, preferably 0.001 to 0.05 part by weight, per 100 parts by weight of the resin component of the resin paint for electrical insulation. The amount used is 0.
If the amount is less than 0001 part by weight, the effect of improving the slipperiness is insufficient, and if it exceeds 1 part by weight, the enamel wire appearance and other properties are adversely affected.

[0011] The above (A), (B)
The method of adding (C) and (C) is not particularly limited.For example, a partially saponified ester wax (A) and low molecular weight polyethylene (B) are dispersed in an organic solvent and added to the resin paint for electrical insulation, and The salt (C) is dissolved or dispersed in an organic solvent and added to the resin paint for electrical insulation. The enameled wire can be obtained by applying and baking the resin composition for electrical insulation of the present invention directly on a conductor or via another insulator. When the resin composition for electrical insulation of the present invention is used, since the lubricant is well dispersed, the effect of suppressing thermal deterioration of the coating film surface at the time of baking is high even when the enamel wire baking conditions are high,
An enameled wire having excellent appearance, slipperiness and abrasion resistance can be obtained.

[0012]

The present invention will be described in more detail with reference to the following examples. In addition, the part in an example means a weight part. Example 1 Hoechst wax OP (partially saponified ester wax, trade name of Hoechst Japan Co., Ltd.) and Hoechst wax PE520 (low molecular weight polyethylene,
Number average molecular weight 2000, trade name of Hoechst Japan)
Was added and melted by heating, and this was rapidly added to 112 parts of xylene at room temperature with rapid stirring to obtain a uniform wax dispersion. Polyamideimide varnish HI-
406 (manufactured by Hitachi Chemical Co., Ltd., resin content 30% by weight) 200
Part, N-methyl-2 in which 0.1% by weight of copper acetate was dissolved.
-6 parts of the pyrrolidone solution and 24 parts of the wax dispersion obtained above were added, and the mixture was stirred and dispersed to obtain a resin composition for electrical insulation.

Example 2 In Example 1, Hoechst wax PE130 (low molecular weight polyethylene, number average molecular weight 3000, trade name, manufactured by Hoechst Japan Ltd.) was used instead of Hoechst wax PE520, and copper (II) chloride was used instead of copper acetate. Except for using, a resin composition for electrical insulation was obtained in the same manner as in Example 1. Example 3 A resin composition for electrical insulation was obtained in the same manner as in Example 1, except that manganese acetate was used instead of copper acetate. Example 4 A resin composition for electrical insulation was obtained in the same manner as in Example 1, except that cobalt acetate was used instead of copper acetate.

Comparative Example 1 A resin composition for electrical insulation was obtained in the same manner as in Example 1 except that copper acetate was not added. Comparative Example 2 In Example 1, a phenolic antioxidant tetrakis- [methylene-3- (3 ′, 5′-) was used in place of copper acetate.
A resin composition for electrical insulation was obtained in the same manner as in Example 1 except that di-tert-butyl-4'-hydroxyphenyl) propionate] methane was used. Comparative Example 3 Insulation was carried out in the same manner as in Example 1 except that phenolic antioxidant 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester was used instead of copper acetate. A resin composition for use was obtained.

Test Example Using the resin compositions for electrical insulation obtained in Examples 1 to 3 and Comparative Examples 1 to 3, a copper wire having a diameter of 1.0 mm was applied and baked according to the baking conditions shown below, and an enameled wire was obtained. Was manufactured. Base: HI-406 (polyamide imide resin varnish, manufactured by Hitachi Chemical Co., Ltd.); 6 dies Upper: Dies twice: Baking furnace: Vertical hot blast stove (Furnace length: 5 m) Furnace temperature: Inlet / outlet = 320 ° C / 430 ° C Linear speed: 14 m / min

Each of the obtained enamel wire films was smooth in appearance and no abnormality was observed. The properties of each enamel wire film were tested by the following methods. The results are shown in Table 1. (1) Flexibility: Checked according to JIS C3003.8.1 (1). (2) Pinhole: Investigated according to JIS C3003.36. (3) Dielectric breakdown voltage: JIS C300 3.11. (2)
It investigated according to. (4) Reciprocating wear: It was examined according to the old JIS C3003.10.1. (5) Static friction coefficient: The static friction coefficient between enamel wires is measured by using a wire slip tester manufactured by Toyo Seiki Co., Ltd., and four enamel wires are placed on the same surface on an inclined table. It is stretched in a divergent shape, and a sled on which two enamel wires identical to the above-mentioned test enamel wire are stretched in parallel so as to intersect with the four enamel wires is placed thereon, and this is gradually inclined from the horizontal position. Then, the sled start angle was read on a tangent scale. The load of the sled is 100g
Set to.

[0017]

[Table 1] Table 1 shows that the enameled wire obtained by using the resin composition for electrical insulation of the present invention has excellent slipperiness and wear resistance.

[0018]

According to the resin composition for electrical insulation of the present invention, a partially saponified ester wax and a low molecular weight polyethylene can be used in combination as a lubricant and can be well dispersed in a paint. Can suppress the thermal deterioration of the coating film surface, so that enameled wire with good slipperiness, abrasion resistance and appearance can be obtained under a wide range of baking conditions, and severe winding, processing and assembly work in recent years Useful for

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI H01B 7/18 H01B 7/18 B (72) Inventor Yasunori Okada 4-3-1 Higashicho, Hitachi City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Inside the Yamazaki Plant (56) References JP-A-56-10554 (JP, A) JP-A-58-27734 (JP, A) JP-A-2-212538 (JP, A) JP-A-4-2066311 (JP, A A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01B 3/30 H01B 7/02 H01B 7/18 C09D 5/25

Claims (2)

(57) [Claims] 1. A resin based on 100 parts by weight of a synthetic resin paint for electrical insulation containing polyamideimide as a resin.
0.1 to 10 parts by weight of partially saponified ester wax,
(B) 0.1 to 10 parts by weight of a low molecular weight polyethylene having a number average molecular weight of 5,000 or less and (C) copper or
An electrically insulating resin composition comprising 0.0001 to 1 part by weight of a metal salt containing manganese or cobalt . 2. An enameled wire obtained by applying and baking the resin composition for electrical insulation according to claim 1 onto a conductor directly or via another insulating material.