JPS60150503A - Self-adhesive insulated wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-bonding insulated wire with excellent coating uniformity and high performance.

In recent years, with the miniaturization and cost reduction of electrical equipment, the use of self-bonding insulated wires has increased due to the omission of tape wrapping and tying cords when manufacturing coils, and the simplification or elimination of impregnated varnish treatments. There is.

Conventionally, such self-bonding electric wires are formed by applying and baking a layer of general insulating paint such as polyurethane, polyvinyl formal, polyester, or polyesterimide resin on the conductor several times to remove this insulation. It is manufactured by applying and baking an insulating paint layer of polyvinyl butyral, polyamide, polyester, phenoxy, epoxy resin, etc., which can generally be heat-fused, on the paint layer once to several times. However, the above-mentioned conventional insulated wire usually requires five or more coatings to form an insulating layer, and in particular, as shown in FIG. , 3, the corner part 1a...
・The layer thickness of the lower layer 2 becomes thinner, and the dielectric breakdown voltage tends to become lower.

The present invention was discovered through extensive research in view of the above-mentioned circumstances, and provides an insulated wire with excellent film uniformity and high withstand voltage compared to conventional general-purpose self-bonding insulated wires. be.

Figures 1 and 2 show a self-bonding insulated wire according to the present invention, where lla is a normal round conductor made of copper, aluminum, an alloy thereof, or a superconductor, and 1.1b is the same. rectangular conductor made of material, etc., 12 each is a conductor 1]
, a, and llb, and 13 are heat-sealable insulating layers formed on the insulating layers 12 and 12, respectively.

The paint used for the acrylic insulating layer 12, in fields where soldering is required, contains acrylonitrile and methacrylic acid esters as essential monomer components, and if desired, other copolymerizable monomers, such as Various insulating paints containing acrylic copolymers obtained by copolymerizing by emulsion polymerization with addition of methacrylic acid, styrene, vinyl acetate, acrylamide, etc.) can be used, but normal soldering is difficult under certain conditions (temperature Considering that it can be soldered at 360°C to 420'C (1 hour 3 seconds to 10 seconds) and has good wire characteristics, methacrylic acid esters should be 35 to 75% by weight.
, a copolymer containing 50 to 15% by weight of acrylonitrile is desirable. As a specific example of this, 100 parts by weight of monolayer units of an acrylic copolymer obtained by emulsion copolymerization are combined with 25 to 50 parts by weight of acrylonitrile and nuccrylic acid as shown in Japanese Patent Publication No. 51-27455. 50 to 75 parts by weight of esters, and 35 to 60 parts by weight of methacrylic esters as shown in Japanese Patent Publication No. 51-39898.

15 to 35 parts by weight of cryloni-1-lyl and 3 to 2 parts by weight of vinyl acetate
0 parts by weight, 3 to 15 parts by weight of methacrylic acid, and appropriate amounts of other vinyl monomers as necessary, Japanese Patent Publication No. 51-3
40 to 60 M parts of methacrylic acid esters, 15 to 45 parts by weight of acrylonitrile, 3 to 25 parts by weight of acrylamides, and 2 to 25 parts by weight of methacrylic acid as shown in Japanese Patent No. 9899.
15 parts by weight, methacrylic acid esters 35-65 as shown in Japanese Patent Publication No. 51-39976
Weight parts and acrylonitrile 10-40 weight S, :JI [
Preferred examples include those consisting of 3 to 20 parts by weight of vinyl, 3 to 20 parts by weight of acrylamide, and 2 to 15 parts by weight of methacrylic acid.

In addition, for fields that do not require soldering, the acrylic insulating layer 12 may include a nitrile compound such as acrylonitrile or methacrylonitrile, and a glycidyl compound such as glycidyl methacrylate or acrylic glycidyl ether as essential monomer components. If desired, other copolymerizable monomers (e.g. styrene, α-methylstyrene, methyl methacrylate, ethyl acrylate, tutaacrylic acid, acrylamide, N-methylol acrylamide, etc.)
Various insulating paints containing acrylic copolymers obtained by adding and copolymerizing by emulsion polymerization etc. can be used. However, the amount of the nitrile compound in the acrylic copolymer is
Preferably, the copolymer contains 0 to 70% by weight, and the amount of the glycidyl compound is 3 to 10% by weight.

On the other hand, the paint used for the heat-fusible insulating layer 13 is a commercially available general polyhinyl butyral-based, polyamide-based, polyester-based, phenoxy-based, or epoxy-based paint for forming a heat-fusible layer. Any paint can be used.

Therefore, it is preferable to form the insulating layer 12 by an electrodeposition coating method. By performing electrodeposition coating, it is possible to perform coating once instead of applying and baking multiple times in the past, and the thickness is uniform with fewer pinholes. Therefore, especially for rectangular wires like the one shown in Figure 2, a uniform insulating layer can be obtained even at the edges, which greatly improves the withstand voltage characteristics, and the insulating layer can be made thinner, which increases the winding density. can be increased. This results in a remarkable effect of further improving the space factor when a rectangular wire is used for winding. Furthermore, it is preferable to form the insulating layer 13 by a dip coating method. The total thickness of the insulating layers 12 and 13 is preferably about 20 to 50 μm, and the thickness of the insulating layer 13 is preferably about 10 to 20 μm, particularly about 15 μm. However, the present invention is not limited to these coating methods, and other coating methods may be employed depending on the shape, size, purpose, or equipment of the electric wire.

The present invention will be specifically illustrated in Examples below.

Example 1 50 parts by weight of methyl methacrylate, acriconyl 1-lyl 3
0 parts by weight, 12 parts by weight of acrylamide, 8 parts by weight of methacrylic acid
parts by weight, sodium lauric acid ester as a surfactant, potassium persulfate-sulfur hydrogen sulfite as a polymerization initiator,
・Using a Lithium Resosox catalyst, 60% in a nitrogen stream
Emulsion polymerization for 4 hours at ~70°C, non-volatile content 20% by weight
A water-dispersible acrylic insulation paint was prepared. This insulating paint was electrodeposited onto the surface of a copper wire having a diameter of 0.5 fi by a conventional method at a line speed of 2 On+/min. Next, apply this painted wire to N.
After being introduced into the vapor of No-dimethylbormamide, 2
The surface was dried at 50°C, and then a polyvinyl butyral paint (manufactured by Takutoku Toyo Co., Ltd., trade name TCV-11) was applied by dipping twice and baked at a temperature of 330°C to form the surface shown in Figure 1. The insulating layer 12 is 25 μm thick and the insulating layer 13 is 1
A round insulated wire I having a thickness of 4 μm was obtained.

Example 2 Polyamide paint (manufactured by Nitto Denko Corporation, trade name DB-20) was used instead of the polyvinyl butyral paint in Example 1.
A round insulated wire (2), in which the insulating layer 12 shown in the first figure was 31 μm thick and the insulating layer 13 was 14 μm thick, was obtained in the same manner as in Example 1, except that 0) was used.

Example 3 A monomer mixture containing 55 parts by weight of acriconyl-1-lyl, 25 M parts of α-methylstyrene, 10 parts by weight of ethyl acrylate, 5 parts by weight of glycidyl methacrylate, and 5 parts by weight of methacrylic acid was used as a surfactant. Sodium lauryl ester as a polymerization initiator, potassium persulfate as a polymerization initiator
Emulsion polymerization was carried out at 60 to 70° C. for 4 hours in a nitrogen stream using a Resosox-based catalyst of sodium bisulfite to obtain a water-dispersed acrylic insulating paint with a nonvolatile content of 20% by weight. Using this insulating paint, electrodeposit coating was applied to the surface of a copper wire with a diameter of 0.5 in the same manner as in Example 1, and then in the same manner as in Example 1, the insulating layer 12 shown in the first diagram was insulated with a thickness of 25 μm. layer 13
A round insulated wire ■ having a thickness of 14 μm was obtained.

Example 4 The insulating layer 12 shown in the first diagram was 31 μm thick and the insulating layer 13 was 14 μm thick in the same manner as in Example 3, except that a polyamide paint (described above) was used instead of the polyvinyl butyral paint in Example 3. A round insulated wire ■ was obtained.

Example 5 The insulating layer 12 shown in the second diagram was made in the same manner as in Example 3 except that a rectangular wire of 1.4×6.0 mm was used as the copper wire.
Flat insulated wire with a thickness of μm and an insulating layer 13 of 15 μm■
I got it. This electric wire V had a uniform insulating layer thickness even at the edge portions.

The insulated wires I to ■ of each of the above examples and the self-fusing insulated wire ■ (round wire 0.5 size, lower layer...
・Polyurethane, 30 μm thick, upper layer...poly-nyl butyral, 15 μm thick), same insulated wire ■ (round wire 0, 5
mm diameter, lower layer... polyester, 25 μm thick, upper layer... polyamide 1 color, 15 μm thick), same rectangular insulated wire (
Flat wire 1.4 x 6.0 s amount, lower layer... Polmar,
30 μm thick, upper layer...polyvinyl butyral, 15
The results of measuring various characteristics for each layer (μm thickness) are shown on the next page. In addition, to measure the fusion strength of round wires, prepare a test piece of each wire with a length of 5Qcm, wipe the surface with flannel cloth to clean it, and
An insulated wire 1. The upper layer 12 of the insulated wire is made of poly-nyl butyral by winding it 12 times so that the wires are in close contact with each other while applying a tension of 0.4 kg to a round wire of L+. IIl, V, ■.

For (2), heat the insulated wire n, TV, and Vl at 150°C for 10 minutes each with a trowel, the upper layer 13 of which is made of polyamide, and then return to room temperature and heat the wires at both ends.
A helical coil of 10 coils was prepared by unwinding the turns by hand, and both ends of this coil were pulled using an automatic Schopper type tensile strength tester, and the tensile force g at which the coil peeled off at the 7th turn was shown. The fusing strength of a rectangular wire is determined by overlapping both ends of the test piece, sandwiching them between clips and fusing them with heat, then pulling both ends of the test piece using an automatic Schopper type tensile strength tester, and measuring the tensile force at which the test piece peels off. Ta.

As described in 2 below, the self-bonding insulated wire according to the present invention is
Since the lower layer of the insulating layer is composed of an acrylic insulating layer, the lower layer 12 can be formed by one-time coating by electrodeposition of a paint using an aqueous solvent, which is extremely advantageous in terms of cost. In addition, in the case of a rectangular wire, an insulating layer having the same thickness as the other parts is formed on the edge portion, so the dielectric breakdown voltage is higher than that of the conventional wire.

The rectangular conductor used in the present invention may include a ribbon-shaped conductor, such as a 0.03X1. A conductor of about Om+m is also included.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a round wire of a self-fusing insulated wire according to the present invention, Fig. 2 is a cross-sectional view of a rectangular wire, and Fig. 3 is a cross-sectional view of a conventional rectangular self-fusing insulated wire. It is a diagram. 11... Conductor, 12... Acrylic insulating layer, 13.
...An insulating layer that can be heat-fused. Applicant Dai-Denko Co., Ltd. Mitsubishi Electric Corporation

Claims (1)

[Claims] / A self-bonding insulated wire comprising an acrylic insulating layer provided on a conductor, and an insulating layer that can be heat-fused on the insulating layer. 2. The self-fusing insulated wire according to claim 1, wherein the acrylic insulating layer is provided by electrodeposition coating. 3. The self-fusing insulated wire according to claim 1 or 2, wherein the acrylic insulating layer is formed using a water-dispersed paint. Isn't polyamide paint used for the heat-sealable insulating layer mentioned above? A self-fusing insulated wire according to any one of claims 1 to 3, which is provided by applying a J-FI coating. 5. The self-fusible insulated wire according to any one of claims 1 to 3, wherein the heat-fusible insulating layer is provided by dip coating a polyvinyl butyral paint. B. The self-bonding insulated wire according to any one of claims 1 to 5, wherein the conductor is round. 7. The self-bonding insulated wire according to any one of claims 1 to 5, wherein the conductor is rectangular.