KR20110130179A - Insulated wire - Google Patents

Abstract

PURPOSE: An insulated wire is provided to obtain superior heat resistance by including an insulating coating layer of which heat resistance and film adhesion are superior. CONSTITUTION: An insulated wire(10) comprises a conductor wire(11), and at least three insulating coating layers formed outside of the conductor wire. The three insulating coating layers comprises: a polyamide imide resin layer(14), of which film thickness is 20-40% comparison to whole insulating coating layer, which is the outermost layer of the insulating coating layer; a polyamide imide resin layer(13) including inorganic particles, of which film thickness is 30-50% comparison to whole insulating layer, which contacts with the outermost layer; a polyamide imide resin layer(12) including adhesion agent, of which film thickness is 20-30% comparison to whole layer, which is the lowermost layer of the insulating coating layer.

Description

Insulated Wire

The present invention relates to an insulated wire for winding having excellent heat resistance.

Recently, as the size reduction and weight reduction tendency of electric or electronic devices increases, smaller and lighter motors having high performance have been required. In order to satisfy this requirement, there has been a need to increase the number of windings wound around the motor core with insulated wire. In order to wind more windings in a narrow space, there has been an increasing demand for motors using split cores that use the winding winding method of the distributed winding method. For this purpose, a larger amount of insulated wire must be forced into the core slot. As a result, excessive current flows in the motor, and excessive current requires heat resistance of the motor. In addition, the insulation coating was burned out due to excessive current. In particular, the use environment may be more serious when exposed to high temperature environment, such as the engine room.

In general, such motors have usually used insulated wires having good thermal properties formed by coating and baking a coating material of polyamide imide having good mechanical strength on a conductor. Today, however, there is a need for a higher performance, yet smaller and lighter motor. In order to satisfy these requirements, it is necessary to further increase the number of windings of the insulated wire, so that the polyamide-imide base insulating coating having good heat resistance may also be damaged. In order to further increase the heat resistance of the insulating coating, a polyimide insulated wire may be used, but in this case, since imidization proceeds when manufacturing the insulated wire, water is generated as a by-product, which makes it difficult to manufacture the insulated wire. come.

Accordingly, the Republic of Korea Patent No. 0483712 discloses a polyimide insulated wire that has eliminated the by-products during the manufacture of the winding, but the present invention is applied to the concentrated winding type motor, the film adhesion is insufficient and the lubricity is insufficient to damage the insulator This is somewhat unreasonable to apply. In addition, by dispersing an inorganic material such as silica in the insulating material resin, but to improve the heat resistance, it is difficult to disperse the inorganic material to a nano size, that is, 100nm or less in the insulating material.

The present invention aims to provide an insulated wire suitable for winding.

Insulated wire of the present invention is a conductor wire; And at least three insulating coating layers formed outside the conductor wires, the insulating wire layer comprising: a polyamide-imide resin layer having a film thickness of 20 to 40% relative to the total insulating coating layer and an outermost layer of the insulating coating layer; A polyamide imide resin layer having a thickness of 30 to 50% of the total insulation coating layer and including inorganic particles which are lower layers in contact with the outermost layer; And a polyamide-imide resin layer having a film thickness of 20 to 30% relative to the entire insulating coating layer and including an adhesion improving agent which is the lowest layer of the insulating coating layer.

Such inorganic particles may be used as one inorganic particle selected from core-shell type inorganic particles having amino groups or carboxyl groups and metal oxides surface-modified with a coupling agent or mixtures thereof. In particular, the core-shell type inorganic particles having the amino group or the carboxyl group are preferably those of the core-shell type silica having the amino group or the carboxyl group. As the metal oxide, magnesium oxide, calcium oxide, scandium oxide, barium oxide, titanium dioxide, zirconium dioxide, or the like is preferably used.

In addition, the inorganic particles may be used in the 5 to 25% by weight compared to the polyamide imide resin layer containing the inorganic particles.

The adhesive force improving agent used for the insulated wire of this invention can use the thing of 0.05-2 weight% compared with the polyamide-imide resin layer containing an adhesive force improving agent.

The insulation coating layer of the insulated wire of this invention is excellent in heat resistance and also excellent in film adhesiveness.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings attached to the present specification illustrate exemplary embodiments of the present invention, and together with the detailed description of the present invention, the present invention is intended to help understand the technical idea of the present invention. No.
1 is a cross-sectional view of an insulated wire having three insulating layers according to an embodiment.

Hereinafter, the present invention will be described in detail. The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Insulated wire of the present invention is a conductor wire; And at least three insulating coating layers formed outside the conductor wires, the insulating wire layer comprising: a polyamide-imide resin layer having a film thickness of 20 to 40% relative to the total insulating coating layer and an outermost layer of the insulating coating layer; A polyamide imide resin layer having a thickness of 30 to 50% of the total insulation coating layer and including inorganic particles which are lower layers in contact with the outermost layer; And a polyamide-imide resin layer having a film thickness of 20 to 30% relative to the entire insulating coating layer and including an adhesion improving agent which is the lowest layer of the insulating coating layer.

Referring to FIG. 1, the insulated wire of the present invention includes at least three insulating coating layers, and according to one embodiment, the insulating wire 10 having three insulating coating layers has a lowermost layer surrounding the conductor wire 11. The polyamide-imide resin layer 12 with an adhesion promoter, the polyamide-imide resin layer 13 with an inorganic particle which is a layer on it, and the polyamide-imide resin layer 14 which is an outermost layer are provided.

As the polyamide imide resin used in the insulating coating layer of the present invention, polyamide imide resin prepared by solution thermal polymerization of aromatic diisocyanates or diamines and polybasic acid anhydrides in an organic solvent can be used. At this time, it is preferable that the content of the acid anhydride used is 0.7-1.3 with respect to diisocyanate, More preferably, it is 0.8-1.2. When the content of acid anhydride to diisocyanate is less than 0.7 or greater than 1.3, the physical properties of the general polyamide imide do not appear.

Specific examples of the aromatic diisocyanate include diphenylmethane-4, 4'-diisocyanate, diphenylmethane-3, 3'-diisocyanate, diphenylmethane-3, 4'-diisocyanate and diphenylether-4. , 4'-diisocyanate, benzophenone-4, 4'-diisocyanate, diphenylsulfon-4, 4'-diisocyanate, tolylene-2, 4-diisocyanate, tolylene-2, 6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, and the like, and the like, and these may be used alone or as a mixture thereof. Among the diisocyanate compounds, diphenylmethane-4 and 4'-diisocyanate are preferred in view of ease of purchase and cost.

As the acid component of the polyamideimide, any acid commonly used may be used. Examples of preferred acids include trimellitic acid such as tribasic acid, trimellitic anhydride, trimellityl chloride or derivatives of trimellitic acid, and the like, but are not limited thereto. Among them, trimellitic anhydride is preferred in view of ease of purchase and cost. Organic solvents include N-methyl-2pyrrolidone, dimethyl acetamide, N, N-dimethyl formamide, and N-methyl-2pyrrolidone is mainly used.

It is preferable that the polyamideimide resin layer 14 which is an outermost layer is 20 to 40% of film thickness compared with the whole insulation coating layer.

In addition, it is preferable that the polyamide-imide resin layer 13 including the inorganic particles as the lower layer in contact with the outermost layer of the present invention has a film thickness of 30 to 50% relative to the entire insulating coating layer, which is less than 30% The increase effect is not seen, and when it exceeds 50%, the film defect of the insulating film is inferior.

Dispersibility problems may occur when dispersing an inorganic material in a polyamide imide resin. To this end, surface modification is performed using a core-shell type inorganic particle having a functional group capable of reacting with the polyamide imide polymer backbone and a coupling agent. By mixing the prepared metal oxides and dispersing them in the polyamide imide, the inorganic particle size in the polyamide imide can be controlled to a nano size, that is, 100 nm or less. In this case, as the core-shell type inorganic particles having a functional group capable of reacting with the polyamide imide polymer backbone, core-shell type inorganic particles having an amino group or a carboxyl group may be used. In particular, the core-shell type inorganic particles having the amino group or the carboxyl group are not particularly limited, but it is preferable to use a core-shell type silica having the amino group or the carboxyl group. As the metal oxide, magnesium oxide, calcium oxide, scandium oxide, barium oxide, titanium dioxide, zirconium dioxide, or the like is preferably used.

In addition, the inorganic particles may be used in the 5 to 25% by weight compared to the polyamide imide resin layer containing the inorganic particles, when less than 5% by weight does not show the effect of the inorganic material, if the weight is greater than 25% by weight The acidity is reduced, and the effect of the inorganic material is not only degraded, but the film is brittle and the film flaw of the insulating film is reduced.

And the lowermost layer 12 of the insulation coating layer of this invention uses the film thickness of 20 to 30% compared with the polyamide-imide resin layer whole insulation coating layer containing an adhesive force improving agent.

The adhesion improving agent used for the insulated wire of this invention includes melamine resins, such as butoxy melamine resin, amines, such as a trialkyl amine, mercaptans, such as a mercapto benz imidazole, and polycarbodiimide resin. It is not limited. Such adhesion improving agent can be used that is 0.05 to 2% by weight relative to the polyamide imide resin layer containing the adhesion improving agent. When the amount of the adhesion enhancer is less than 0.05% by weight, the effect of improving the adhesion is not obtained, and when it exceeds 2% by weight, the adhesion is rather reduced due to the excessive adhesion enhancer.

Hereinafter, the present invention will be described in detail with reference to Examples. However, embodiments according to the present invention can be modified in many different forms, the scope of the present invention should not be construed as limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Example

Preparation Example 1 Polyamideimide Synthesis (PAI 1)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin.

Preparation Example 2 Synthesis of Inorganic Materials Dispersed Polyamideimide (PAI 2)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin. After dissolving the core-shell type silica having amino groups in NMP, it is mixed with a metal oxide having a size of about 70 nm surface-modified with a silane coupling agent and sonicated to give a nano silica-metal oxide solution. Was prepared. The nano-silica-metal oxide solution was added to the polyamide-imide solution synthesized above so that the silica and the metal oxide were 10 parts by weight based on 100 parts by weight of the polyamide imide resin.

Preparation Example 3 Synthesis of Inorganic Materials Dispersed Polyamideimide (PAI 3)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin. The core-shell type silica having amino groups was dissolved in NMP, mixed with a metal oxide having a size of about 70 nm surface-modified with a silane coupling agent, and sonicated to prepare a nano silica-metal oxide solution. Ready. The nano-silica-metal oxide solution was added to the polyamide-imide solution synthesized above so that the silica and the metal oxide were 20 parts by weight based on 100 parts by weight of the polyamide imide resin.

Preparation Example 4 Synthesis of Polyamide-imide with Adhesion Enhancer (PAI 4)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin. 0.1 part by weight of the butylated melamine resin was stirred with respect to 100 parts by weight of the synthesized polyamideimide resin.

Preparation Example 5 Synthesis of Polyamide-imide with Adhesion Enhancer (PAI 5)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin. 0.5 part by weight of the butylated melamine resin was stirred with respect to 100 parts by weight of the synthesized polyamideimide resin.

Preparation Example 6 Synthesis of Polyamide-imide with Adhesion Enhancer (PAI 6)

In a four-necked flask equipped with a stirrer and a condenser well dried at room temperature, 510.0 parts by weight of N-methyl pyrrolidone was added, and 201 parts by weight of trimellitic dianhydride was added to start stirring. . Thereafter, 250 parts by weight of diphenylmethane-4 and 4'-diisocyanate (MDI) were added thereto, and the temperature was gradually increased from 80 ° C to 140 ° C to synthesize a polyamideimide resin. 1 part by weight of the butylated melamine resin was stirred with respect to 100 parts by weight of the synthesized polyamideimide resin.

Example 1

After coating the polyamideimide resin obtained from PAI 5 from the lower layer on a flat oxygen-free copper having a corner radius R of 0.5 mm at a thickness of 1.5 x 2.0 mm (thickness x width) and drying it to form an 8 mu m insulating film, the lower polyamide was formed. The polyamide-imide resin in which the inorganic material obtained in PAI 2 was dispersed was coated on the mid resin, followed by drying by heating to form a 16 µm insulating film. The polyamide-imide resin obtained in PAI 1 was again coated thereon to form an insulating coating having a thickness of 16 μm, thereby producing a flat insulated wire having a thickness of 40 μm.

Example 2-10

Each Example 2-10 was prepared in the same manner as in Example 1 in the ingredients and ratios shown in Table 1 below.

Comparative Example 1-2

Each Comparative Example 1-2 was prepared in the same manner as in Example 1 with the ingredients and the proportions shown in Table 1 below.

Example Comparative example One 2 3 4 5 6 7 8 9 10 One 2 substratum
(Μm) 8
PAI 5 12
PAI 5 16
PAI 5 12
PAI 5 12
PAI 5 16
PAI 5 8
PAI 5 12
PAI 5 12
PAI 4 12
PAI 6 4
PAI 5 12
PAI 5 Middle layer
(Μm) 16
PAI 2 16
PAI 2 16
PAI 2 12
PAI 2 20
PAI 2 12
PAI 2 20
PAI 2 16
PAI 2 16
PAI 2 16
PAI 2 16
PAI 2 8
PAI 2 Upper layer
(Μm) 16
PAI 1 12
PAI 1 8
PAI 1 16
PAI 1 8
PAI 1 12
PAI 1 12
PAI 1 12
PAI 1 12
PAI 1 12
PAI 1 20
PAI 1 20
PAI 1

Test example. Property measurement

Salt test layer

After fixing the specimen of about 50cm in length of the insulated wire prepared in Example 1-10 and Comparative Example 1-2 at the end of the salt testing machine and applying a load of 800g to one end. The tester was operated after the top and bottom coatings of the specimens were removed. The rotational speed at the time of breaking the film was measured and shown in Table 2 below.

Film defect

In order to make the specimen of about 40 cm of the insulated wire prepared in Example 1-10 and Comparative Example 1-2 into the elongated S-shape, the mandrel hoisting test equipment was bent 180 ° in two directions and the coating material Cracking and / or peeling were observed. The minimum mandrel diameter d (mm), which is not cracked or peeled off, is recorded in Table 2 below.

Flame retardant

Take one specimen of about 20cm in length of the insulated wire prepared in Example 1-10 and Comparative Example 1-2, place a 1.6mm diameter smooth steel ball on the surface of the butterfly and apply a load of 1000g on it This was put in a thermostat and measured, and is shown in Table 2 below.

Breakdown Voltage

Specimens of the insulated wires prepared in Examples 1-10 and Comparative Examples 1-2 were prepared, and the metal foil method was performed according to JIS C 3003. Table 2 shows the average value of five specimens.

Heat resistance

The specimens of the insulated wires prepared in Examples 1-10 and Comparative Examples 1-2 were prepared and left in a 220 ° C. oven for 7 days and then subjected to a metal foil method in accordance with JIS C 3003. Table 2 shows the average value of five specimens. The percentage values in Table 2 below mean a comparison with the breakdown voltage.

Example Comparative example One 2 3 4 5 6 7 8 9 10 One 2 Dye (sashimi) 74 79 83 78 79 84 73 71 73 77 59 80 Film defect 1d 1d 1d 1d 1d 1d 1d 1d 1d 1d 1d 2d Flame Retardant (℃) 414 411 409 410 415 407 417 423 416 407 410 381 Breakdown voltage
(V) 6700 6850 6900 6540 7120 6670 7090 7160 6790 6910 5920 5860 Residual resistance
(V) 5540
82.7% 5690
83.1% 5750
83.3% 5330
81.5% 6070
85.3% 5500
82.5% 6000
84.6% 6170
86.2% 5660
83.4% 5720
82.8% 3690
62.3% 3330
56.8%

Examples 1-10 showed good test results. In particular, it exhibited a good level of heat resistance at 400 ° C. or more of flame retardancy and 80% or more of residual heat resistance. On the other hand, Comparative Example 1 has a low proportion of PAI 5, which is a polyamide imide resin layer containing an adhesion improving agent, and thus does not have adequate adhesion. Comparative Example 2 has a low proportion of PAI 2, a polyamide imide layer in which an inorganic material is dispersed. Heat resistance is inferior.

10: insulated wire 11: conductor wire
12: Polyamide-imide resin layer with adhesion promoter
13: polyamide imide resin layer containing inorganic particles
14 polyamide-imide resin layer

Claims (6)

Conductor wire; And at least three insulating coating layers formed outside the conductor wires.
A polyamide imide resin layer having a film thickness of 20 to 40% relative to the entire insulating coating layer and being the outermost layer of the insulating coating layer;
A polyamide imide resin layer having a thickness of 30 to 50% of the total insulation coating layer and including inorganic particles which are lower layers in contact with the outermost layer; And
An insulated wire, comprising: a polyamide-imide resin layer having a film thickness of 20 to 30% relative to the total insulating coating layer and comprising an adhesion improving agent which is the lowest layer of the insulating coating layer. The method of claim 1,
The inorganic particle is an insulated wire, characterized in that the inorganic particles of the core-shell type having an amino group or a carboxyl group and one type of inorganic particles or a mixture thereof selected from metal oxides surface-modified with a coupling agent. The method of claim 2,
The core-shell type inorganic particle having an amino group or a carboxyl group is an insulated wire, characterized in that the core-shell type silica having an amino group or a carboxyl group. The method of claim 2,
The metal oxide is an insulated wire, characterized in that the compound or a mixture of two or more selected from magnesium oxide, calcium oxide, scandinanium oxide, barium oxide, titanium dioxide and zirconium dioxide. The method of claim 1,
The inorganic particles are insulated wire, characterized in that 5 to 25% by weight relative to the polyamide imide resin layer containing inorganic particles. The method of claim 1,
The adhesion force improving agent is an insulated wire, characterized in that 0.05 to 2% by weight relative to the polyamide-imide resin layer containing the adhesion force improving agent.

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