JPH0762967B2 - Self-lubricating insulated wire - Google Patents

Description

TECHNICAL FIELD The present invention relates to an insulated wire having excellent self-lubricating property and workability.

[Prior art and its problems]

In the coil processing process in the manufacture of electrical equipment in recent years,
The rationalization has been actively carried out, and the coil winding work is shifting from the conventional manual winding process to high-speed mechanical winding process by introducing an automatic winding machine.

However, when forming a coil by this high-speed mechanical winding process, a large tension is applied to the insulated wire, and at the same time, because the speed is high, the insulated wire itself is easily damaged, and therefore the reliability of the obtained coil is significantly reduced. there were.

Therefore, a method of reducing the friction coefficient of the surface of the insulated wire and protecting the surface of the insulated wire by applying wax or lubricant to the surface of the insulated wire has not been obtained yet.

Further, when an insulated electric wire such as a motor of a refrigerator is used in a refrigerant, a winning agent which dissolves in the refrigerant and adversely affects the equipment cannot be used.

[Object of the Invention]

The present invention is intended to provide an insulated electric wire which is excellent in self-lubricating property and abrasion resistance and can be used also as a refrigerant resistant winding.

[Means for solving problems]

The self-lubricating insulated wire of the present invention has a molecular weight of 2000 to 6500 and a density of 0.92 to 0.
A baking coating layer of an insulating paint, which is obtained by adding 0.1 to 10% by weight of 98 g / cc polyethylene and 0.1 to 5% by weight of a hindered phenol oxidative deterioration inhibitor, is provided directly or through another insulating coating layer. It is characterized by that.

The baking type insulating paint used for forming the insulating coating layer of the self-lubricating insulated wire in the present invention is not particularly limited, but for example, polyester, phenoxy,
Polyurethane and the like, and polyvinyl formal, polyester imide, polyamide imide, polyamide, polyimide and the like, which have excellent refrigerant resistance, can be mentioned.

Polyethylene has a molecular weight of 2000-6500 and a density of
The wear resistance of the paint film obtained by using medium density polyethylene of about 0.92 to 0.98 (g / cc) is particularly good.

Commercial products of such medium density polyethylene include Hiwax 410P and Hiwax 210P manufactured by Mitsui Petrochemicals, and Sunwax 131P manufactured by Mitsui Chemicals.

In the present invention, the reason for adding the amount of polyethylene in the range of 0.1 to 10% by weight with respect to the resin component in the insulating coating is that when the amount of polyethylene added is less than 0.1% by weight, the self-lubricating effect of the baked coating obtained is insufficient. It is sufficient, and if it exceeds 10% by weight, the self-lubricating effect reaches saturation and the anti-wear resistance decreases.

Examples of the hindered phenol-based oxidative deterioration inhibitor include triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] and pentaerythrityl-tetrakis [3- (3 .
5-di-t-butyl-4-hydroxyphenyl) propionate] and N, N'-hexamethylenebis (3.5-di-t-butyl-4-hydroxy-hydrocinnamamide).

Further, this polyethylene has a sufficiently good lubricating effect in the presence of the oxidative deterioration inhibitor, and cannot obtain the effect in the absence of the oxidative deterioration inhibitor.

The reason for limiting the addition amount of the oxidative deterioration inhibitor to 0.1 to 5% by weight is that the self-lubricating effect cannot be obtained when the amount is less than 0.1% by weight with respect to the resin component of the insulating coating, and the addition amount exceeds 5% by weight. This is because the wear resistance is reduced.

The insulating coating material for forming the insulating coating layer of the self-lubricating insulated wire of the present invention is prepared by dissolving the above-mentioned resin component in a solvent such as solvent naphtha, cresol, N-methylpyrrolidone or dimethylformamide, and adding the above-mentioned polyethylene thereto. It is prepared by uniformly dispersing while heating above the melting point of the blended polyethylene, and then blending the hindered phenol-based oxidative deterioration inhibitor dissolved in a solvent such as solvent naphtha or cresol.

In order to save the trouble of heating polyethylene above the melting point of polyethylene after blending polyethylene in preparing this insulating coating, dissolve polyethylene once in a solvent such as heated solvent naphtha and then rapidly cool it with sufficient stirring to form a polyethylene dispersion and mix it. Apply the method.

The insulated wire of the present invention can be made into an insulated wire by directly applying an insulating paint containing polyethylene and a hindered phenolic antioxidant on a conductor and repeating coating and baking. Since the uppermost layer of the electric wire insulating layer is caused by the lubricity, the same effect can be obtained even if it is formed via another insulating layer.

Next, the present invention will be described in detail using examples and comparative examples.

(Example 1) Commercially available polyester imide insulating paint [ISOMID 40VT
(Nippon Schenectady Co., Ltd.)]
0, density of 0.94 (g / cc) polyethylene dispersed in solvent naphtha and N, N'-hexamethylene bis (3.5-di-t-butyl-4-hydroxy-hydrocinnamamide) in solvent naphtha Each of the dissolved substances was mixed so as to be 0.5% by weight with respect to the resin component of the polyesterimide insulating coating material, and sufficiently stirred to obtain a uniform coating material.

The insulating paint thus obtained was baked on a 10 mmφ copper wire at a baking temperature of 400 ° C.
After baking, an insulated electric wire with a film thickness of 35μ was obtained.

(Comparative Example 1) Commercially available polyester imide insulating paint [ISOMID 40VT
(Nichitsu Schenectady Co., Ltd.)] as it is 1.0 mm
An insulated electric wire was obtained by baking on a φ copper wire at a baking temperature of 400 ° C.

(Examples 2 to 7) (Comparative Examples 2 to 7) Commercially available polyamide-imide resin paint [HI-405-25 (manufactured by Hitachi Chemical Co., Ltd.)] was baked at a baking temperature of 32 μm.
After baking at 400 ° C., polyethylene imide having an average molecular weight of 6000 and a density of 0.96 (g / cc) was dispersed in a solvent naphtha, and pentaerythrityl-tetrakis [3- (3.5-di- t-butyl-4
-Hydroxyphenyl) propionate] dissolved in solvent naphtha was mixed at a ratio shown in Table 1 with respect to the resin ratio in the paint and sufficiently stirred to obtain a uniform paint.

Each of the paints thus obtained was applied onto a copper wire having a diameter of 1.0 m / m to obtain a polyamide-imide insulated electric wire having a total thickness of 35 µm.

(Comparative Example 8) A commercially available polyamide-imide resin coating material (HI-405-25 (manufactured by Hitachi Chemical Co., Ltd.)) was applied to a baking temperature so that the coating thickness would be 32 μm.
Baking at 400 ° C., and further, polyethylene imide having an average molecular weight of 1,000 and a density of 0.90 (g / cc) dispersed in a solvent naphtha, and pentaerythrityl-tetrakis [3- (3.5- The-t-
Butyl-4-hydroxyphenyl) propionate] was dissolved in solvent naphtha and mixed so as to be 1.0% by weight with respect to the resin ratio in the paint, and stirred sufficiently to obtain a uniform paint and baking. , The film thickness is all layers
A 35μ polyamide-imide insulated wire was obtained.

(Comparative Example 9) The polyethylene of Comparative Example 8 was prepared with an average molecular weight of 7,000 and a density.
Using 0.94 (g / cc), the other conditions were the same, and a polyamide-imide insulated wire with a total film thickness of 35μ was obtained.

(Comparative Example 10) A commercially available polyamide-imide resin coating material (HI-405-25 (manufactured by Hitachi Chemical Co., Ltd.)) was baked to a coating thickness of 32μ.
Baking at 400 ° C, and further, on this polyamideimide resin coating, polyethylene having an average molecular weight of 6,000 and a density of 0.96 (g / cc) dispersed in solvent naphtha, and N-phenyl- which is an amine antioxidant A mixture of 1-naphthylamine dissolved in solvent naphtha was added to the coating resin in an amount of 1.0% by weight, and the mixture was sufficiently stirred to form a uniform coating, which was baked once. A polyamide-imide resin insulated wire having a total thickness of 35μ was obtained.

The characteristics of the thus obtained Examples and Comparative Examples were evaluated.

The results obtained are shown in Table 1.

The one-way abrasion test in Table 1 was performed according to JIS standard C3003.

In the reciprocating wear test, the test piece was heat-treated and mounted on a reciprocating wear resistance tester with a bead needle and a weight, and the wear amplitude was 10 m.
It complies with JIS C3003, 76, dated June 1, 1976, which measures the number of times of wear until a conductor is visible by giving reciprocating wear of 60 m / min.

The coefficient of static friction is measured by the coefficient of friction between wires. The method of measurement is that two sample electric wires are attached in parallel to a metallic block, and two parallel sample electric wires are placed on a horizontal plate. When the former is pulled horizontally and the former block starts moving, the tensile load is (A) g and the block weight is (a) g.
The static friction coefficient (μs) is expressed by the following equation.

[Effect of the Invention] As is apparent from Table 1, the self-lubricating insulated wire of the present invention is excellent in self-lubricating property and wear resistance, and is industrially useful.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-49-41868 (JP, A) JP-A-49-117984 (JP, A) JP-A-50-63488 (JP, A) JP-A-56- 86410 (JP, A) JP 56-152108 (JP, A) JP 57-74907 (JP, A) Actually opened 57-158726 (JP, U) JP 47-45473 (JP, B1) "Polyethylene resin" (Plastic material course ▲ ○ 4 ▼) edited by Taro Okaei and Kyo Yamagata (August 30, 1969) Nikkan Kogyo Shimbun, pp. 205-206, Japan Iraqox Catalog ○ R ▼ 1076 (Document ▲ No. ▼ H-A-3) (April 1973 revision)

Claims (1)

[Claims] 1. Polyethylene having a molecular weight of 2000 to 6500 and a density of 0.92 to 0.98 g / cc is 0.1 to 10% by weight, and a hindered phenol-based antioxidant is 0.1 to 5 with respect to the resin component in the baking type insulating paint on the conductor. A self-lubricating insulated electric wire, characterized in that a baking coating layer of an insulating coating material added by weight% is provided directly or through another insulating coating layer.