JPH04329216A - Insulated electric wire - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a fracture or crack at the time of bending or winding-around, or of heating in a wound condition in particular. CONSTITUTION:Ultraviolet-ray hardenable resin composition layers different in hardness are characteristically coated on a conductor 1 in a multilayer form.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated wire using an ultraviolet curable resin composition as an insulating material.

0002

[Prior technology] Up until now, electric wires and cables have mainly been made of rubber.
Plastic materials have been obtained by extrusion coating.

Rubber materials are divided into natural rubber and synthetic rubber, and synthetic rubber is mainly used for electric wires, including styrene/butadiene rubber, chloroprene rubber, butyl rubber, isobrene rubber, butadiene rubber, ethylene propylene rubber, urethane rubber, etc. There is.

Plastic materials are broadly divided into thermoplastic resins and thermosetting resins. Typical thermoplastic resins include polyvinyl chloride, polyethylene, chlorinated polyethylene, ethylene-vinyl acetate copolymer resin, and chlorinated resin. Vinyl-vinyl acetate graft copolymer resin, polyurethane,
Fluororesin, polypropylene, polyethylene terephthalate, and modified resins of these are used.

Typical thermosetting resins include epoxy resins, phenol resins, polyimides, polyamides, urea resins, melamine resins, polysulfones, and amidimides.

[0006] In recent years, with the miniaturization and weight reduction of computers, audio equipment, automobiles, aircraft, and artificial satellites, the electric cables used therein have also become smaller in diameter and thinner. One method is to make the insulating film thinner. The thinner the coating is, the more likely it is to be affected by strain caused by the temperature difference between the coating material and the conductor, which is likely to cause a decrease in elongation. For this reason, the conductor is often preheated, but if the conductor becomes thinner, it is undesirable because not only the strength decreases due to the heat of preheating, but also wire breakage is likely to occur due to the pressure of the material during extrusion. On the other hand, it is well known that a method of applying a liquid paint is effective as a means of thinning the film. One example is a method of applying a liquid thermosetting varnish containing 50% or more of organic solvent and baking it with heat, as seen in enameled wire. Although this method is very effective in obtaining a thin film, it usually requires repeating the coating and baking process five or more times, requires extensive safety equipment because it uses a solvent, and is susceptible to baking. Unlike polyethylene and polyvinyl chloride, which cannot be easily colored arbitrarily, it is not easy to identify them when wiring, and they have poor peelability, making them difficult to coat for electrical wires and cables used in electronic equipment. Undesirable.

[0007] Solvent-free, liquid UV-curable resin compositions are attracting attention as a means of achieving this thin coating, and this UV-curable resin composition is used as a coating material for optical fibers. well known. This method includes radical polymerization, ionic polymerization, cationic polymerization, etc. using ultraviolet rays, and the method of curing mainly by radical polymerization is well known. Since it is liquid, it is easy to apply thin coatings and has a fast curing speed, which has a great effect on productivity. Furthermore, it is solvent-free and has higher safety than thermosetting varnishes used for enameled wires, and can be coated once or several times to obtain a desired film thickness. It also has the advantage that it is easy to make a colorless and transparent resin composition, and by adding a coloring agent, it can be colored more easily than thermosetting varnish.

[0008]

[Problems to be Solved by the Invention] An insulated wire with a thin insulation coating can be easily obtained by coating a conductor with the above-mentioned ultraviolet curable resin composition and curing it by irradiating it with ultraviolet rays. However, compositions obtained by curing such liquid resin compositions through polymerization and crosslinking reactions are often accompanied by shrinkage during polymerization.
Furthermore, since it is a nearly completely crosslinked product, it has low elongation and is prone to cracking and cracking due to self-diameter winding and additional heating of the winding. In particular, in the case of a stranded wire conductor, bending or winding causes misalignment or flaking between the strands, which applies force to the covering material, making it more likely to crack or break.

[0009] An object of the present invention is to provide an insulated wire which solves the problems of the prior art described above and which makes it possible to prevent cracks and cracks from occurring during bending and winding.

0010

[Means for Solving the Problems] The present inventor has conducted various research and development based on the knowledge of using ultraviolet curable resin compositions as insulating materials, and as a result, has developed two or more types of ultraviolet curable resins having different hardnesses. By using the composition, it was possible to prevent the occurrence of cracks and cracks during bending and wrapping.

That is, the insulated wire of the present invention is formed by coating a conductor with a plurality of layers of ultraviolet curable resin compositions having different hardnesses.

[0012] In the present invention, the material of the conductor is copper,
Any material that conducts electricity, such as aluminum, iron, platinum, or silver, may be used, and alloys thereof or materials plated with tin, silver, nickel, or the like may be used, and there are no particular limitations. Further, the conductor structure may be either a single wire or a twisted wire.

The ultraviolet curable resin composition may be one that is cured by ultraviolet rays. It basically consists of photopolymerizable oligomers, photopolymerizable monomers, photoinitiators, etc.

Examples of photopolymerizable oligomers include epoxy acrylate, epoxidized oil acrylate, urethane acrylate, polyester urethane acrylate, polyether urethane acrylate, unsaturated polyester, polyester acrylate, polyether acrylate, and vinyl. /Acrylate-based, polyene/
Thiol type, silicone acrylate type, polybutadiene acrylate type, polystylethyl methacrylate type,
Examples include polycarbonate diacrylate, and fluorinated products thereof may be used, such as acryloyl groups with unsaturated double bonds (CH2 = COCO-), methacryloyl groups (CH2 = C(CH3)CO-), and allyl groups. (
CH2 = CHCH2 -), vinyl group (CH2 = C
It is sufficient if it has two or more functional groups such as H-). Further, a combination of a plurality of these may be used.

Examples of photopolymerizable monomers include those having one or more acryloyl or methacryloyl groups per molecule, and known reactive diluents having a vinyl group (CH2=CH-). For example, allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, butoxyethyl acrylate, butoxymethacrylate, butoxyethyl methacrylate, butadiol monoacrylate, butoxytriethylene glycol acrylate, t-butylaminoethyl methacrylate, caprolactone acrylate, 3-chloro -2-hydroxypropyl methacrylate, 2-cyanoethyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, cycloaliphatic modified neopentyl glycol acrylate, 2,3-dibromopropyl acrylate, 2,3-dibromopropyl methacrylate,
Dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, N. N-diethylaminoethyl acrylate, N. N-diethylaminoethyl methacrylate, N. N-dimethylaminoethyl acrylate, N.
N-dimethylaminoethyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, 2(2-ethoxyethoxy)ethyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, glycerol methacrylate, glycidyl acrylate, glycidyl methacrylate, heptadeca Fluorodecyl acrylate, heptadecafluorodecyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, caprolactone-modified 2-hydroxyethyl acrylate, caprolactone-modified 2-hydroxyethyl methacrylate, 2-
Hydroxy-3-methacryloxypropyltrimethylammonium chloride, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, isobonyl acrylate, isobonyl methacrylate, isodecyl acrylate, isodecyl methacrylate, isooctyl acrylate, lauryl acrylate, lauryl methacrylate, r -methacryloxypropyltrimethoxysilane, 2-methoxyethyl acrylate, methoxydiethylene glycol methacrylate, methoxytriethylene glycol acrylate, methoxytriethylene glycol methacrylate, methoxytetraethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, methoxydipropylene glycol acrylate, methoxylated cyclo decatriene acrylate, morpholine acrylate, nonylphenyl polyethylene glycol acrylate, nonylphenoxy polypropylene glycol acrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, octyl acrylate, phenoxyhydroxypropyl acrylate, phenoxyethyl acrylate,
Phenoxyethyl methacrylate, phenoxydiethylene glycol acrylate, phenoxytetraethylene glycol acrylate, phenoxyhexaethylene glycol acrylate, EO modified phenoxylated phosphoric acid acrylate, EO modified phenoxylated phosphoric acid methacrylate, phenyl methacrylate, EO modified phosphoric acid acrylate, EO modified phosphoric acid methacrylate , EO modified butoxylated phosphoric acid acrylate, EO modified butoxylated phosphoric acid methacrylate, EO modified octoxylated phosphoric acid acrylate, EO modified octoxylated phosphoric acid methacrylate, EO modified phthalic acid acrylate, EO modified phthalic acid methacrylate, polyethylene glycol methacrylate, polypropylene Glycol methacrylate, polyethylene glycol/polypropylene glycol methacrylate, polyethylene glycol/polybutylene glycol methacrylate, stearyl acrylate, stearyl methacrylate, EO modified succinic acid acrylate, EO modified succinic acid methacrylate, sulfonic acid soda ethoxy acrylate, sulfonic acid soda ethoxy methacrylate,
Tetrafluoropropyl acrylate, tetrafluoropropyl methacrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, caprolactane-modified tetrahydrofurfuryl acrylate, trifluoroethyl acrylate, trifluoroethyl methacrylate, vinyl acetate, N-vinylcaprolactam, N-vinylpyrrolidone, Styrene, allylated cyclohexyl diacrylate, allylated isocyanurate,
Bis(acryloxyneopentyl glycol) adipate, EO-modified bisphenol A diacrylate, EO-modified bisphenol S diacrylate, bisphenol A
Dimethacrylate, EO modified bisphenol A dimethacrylate, EO modified bisphenol F diacrylate,
1.4-butanediol diacrylate, 1.4-butadiol dimethacrylate, 1.3-butylene glycol dimethacrylate, dicyclopentanyl diacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, dipentaerythritol hexaacrylate, dipenta Erythritol monohydroxypentaacrylate, alkyl-modified dipentaerythritol pentaacrylate, alkyl-modified dipentaerythritol tetraacrylate, acrylic-modified dipentaerythritol triacrylate, caprolactone-modified dipentaerythritol hexaacrylate, ditrimethylolpropane tetraacrylate, ECH-modified ethylene glycol diacrylate Acrylate, ethylene glycol dimethacrylate, ECH modified ethylene glycol dimethacrylate, glycerol acrylate/methacrylate, glycerol dimethacrylate, ECH modified glycerol triacrylate, 1,6-hexanediol diacrylate, ECH modified 1,6-hexanediol acrylate, 1. 6-hexanediol dimethacrylate, long chain aliphatic diacrylate, long chain aliphatic dimethacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, hydroxypivalic acid neopentyl glycol diacrylate, caprolactone modification Hydroxypivalic acid neopentyl glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, stearic acid-modified pentaerythritol diacrylate, EO-modified phosphoric acid triacrylate, EO-modified phosphoric acid diacrylate, EO-modified phosphoric acid Dimethacrylate, ECH-modified phthalic acid diacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, ECH-modified propylene glycol diacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, tetra Bromobisphenol A diacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol divinyl ether, trigcerol diacrylate, neopentyl glycol modified trimethylolpropane diacrylate, trimethylolpropane triacrylate, EO modified trimethylol Propane triacrylate, PO modified trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ECH modified trimethylolpropane triacrylate, tripropylene glycol diacrylate, tris (acryloxyethyl) isocyanurate, caprolactone modified tris (acryloxyethyl) isocyanurate There are others such as tris(methacryloxyethyl)isocyanurate and tris(methacryloxyethyl)isocyanurate, and these may be used alone or in combination of two or more as required.

As the photoinitiator (sensitizer), 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl- 1-phenylpropan-1-one, 1-
(4-isopropylphenyl)-2-hydroxy-2-
Methylpropan-1-one, 1-(4-dodecylphenyl)-2-hydroxy-2-methylpropan-1-one,
4-(2-hydroxyethoxy-2-propyl)ketone, 1-hydroxycyclohexylphenylketone, 2-
Acetophenones such as methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1, benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, bezoin isobutyl ether, benzyl methyl ketal, etc. system, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone,
Hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3.3'-dimethyl-4-methoxybenzophenone, 3.3'. 4. Benzophenone series such as 4'-tetra(t-butylperoxycarbonyl)benzophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2.4-dimethylthioxanthone, isopropylthioxanthone, 2 .4-dichlorothioxanthone, 2.4-diethylthioxanthone, 2.4
- In addition to thioxanthone series such as diisopropylthioxanthone, 2.4.6. - Trimethylbenzoyldiphenylphosphine oxide, methylphenylglyoxylate, benzyl, 9.10-phenanthrenequinone, camphorquinone, dibensuberone, 2-ethylanthraquinone, 4'. A known photoinitiator such as 4'' diethylisotaferone, or one that causes a polymerization reaction by ultraviolet rays may also be used.

Although the difference in hardness of the ultraviolet curable resin composition is not particularly limited, it is preferably 5 or more, preferably 10 or more. Further, it is desirable that the innermost layer has the lowest hardness, and the hardness is preferably increased toward the outermost layer.

Therefore, by coating a conductor with multiple layers of ultraviolet curable resin compositions having different hardness to form a plurality of insulating layers having different hardness, the coating material (insulating layer) is acted upon during bending and wrapping. The force is alleviated by multiple insulating layers, and especially when the conductor is a stranded wire, when the conductor is bent or wound, the wires may shift or split, causing strain and stress on the insulating layer. However, by forming multiple insulating layers with different hardness, the strain and stress caused by misalignment and peeling are alleviated, so cracks and cracks are more likely to occur during bending and wrapping. It becomes possible to prevent the occurrence.

In the present invention, in addition to the above-mentioned components, a photoinitiation aid, an adhesion promoter, a thixotropic agent, a filler, a plasticizer, a non-reactive polymer, a coloring agent, a flame retardant, a flame retardant aid are used as necessary. ，
Anti-softening agent, desiccant, dispersant, wetting agent, anti-settling agent, thickener, anti-color separation agent, anti-static agent, anti-static agent, ultraviolet absorber, anti-mold agent, anti-rat agent, anti-termite agent , fire retardants, matting agents, anti-blocking agents, brighteners, anti-skinning agents, and other various inorganic and organic compounds can be used in combination.

[0020]

[Examples] Examples of the present invention will be described below.

[Example 1] Tin-plated annealed copper stranded wire conductor 28
Shore hardness D60 on AWG (7/0.127)
After coating with a urethane acrylate-based ultraviolet curable resin composition (viscosity 560 cps at 25°C), this was cured in an ultraviolet irradiation oven to form a first insulating layer with an insulation thickness of about 10 μm, and then a first insulating layer with an insulation thickness of about 10 μm was formed. Shore hardness D85
After coating with a urethane acrylate ultraviolet curable resin composition (viscosity 6800 cps at 25 °C),
This was cured through an ultraviolet irradiation oven to form two insulating layers 2 and 3 on the conductor 1, with an insulation thickness of approximately 4.
An insulated wire 4 of 9 μm was obtained.

[Example 2] Tin-plated annealed copper stranded wire conductor 28
Shore hardness D50 on AWG (7/0.127)
After coating with a urethane acrylate-based ultraviolet curable resin composition (viscosity 2500 cps at 25°C), this was cured through an ultraviolet irradiation oven to obtain an insulation thickness of approximately 10 μm.
A first insulating layer with a Shore hardness of D8 is formed thereon.
Urethane acrylate-based ultraviolet curable resin composition of No. 9 (
After coating the wire with a viscosity of 8,700 cps at 25° C., it is cured in an ultraviolet irradiation oven, and as shown in FIG. Obtained.

[Comparative Example 1] Tin-plated annealed copper stranded wire conductor 28
On AWG (7/0.127), a urethane acrylate ultraviolet curable resin composition (viscosity 6
800 cps at 25° C.), this was cured through an ultraviolet irradiation oven to obtain an insulated wire with an insulation thickness of about 51 μm.

[Comparative Example 2] Tin-plated annealed copper stranded wire conductor 28
On AWG (7/0.127), a urethane acrylate-based ultraviolet curable resin composition (viscosity 5
60 cps at 25[deg.] C.) and then cured in an ultraviolet irradiation oven to obtain an insulated wire with an insulation thickness of about 50 [mu]m.

[Comparative Example 3] Tin-plated annealed copper stranded wire conductor 28
Shore hardness D80 on AWG (7/0.127)
After coating with a urethane acrylate-based ultraviolet curable resin composition (viscosity 2000 cps at 25°C), this was cured through an ultraviolet irradiation oven to obtain an insulation thickness of approximately 10 μm.
A first insulating layer with a Shore hardness of D8 is formed thereon.
Urethane acrylate-based ultraviolet curable resin composition of No. 9 (
After coating the wire with a viscosity of 8,700 cps at 25° C., it was cured in an ultraviolet irradiation oven, and as shown in FIG. Obtained.

The characteristics of the electric wire thus obtained were investigated in terms of self-radial winding, self-radial winding added heat, soldering heat resistance, insulation resistance constant, and tensile properties, and the results are shown in Table 1.

[0027]

[Table 1]

As is clear from the results shown in Table 1,
In Examples 1 and 2 according to the present invention, self-radial winding, self-radial winding added heat, and soldering heat resistance are both good, and the insulation resistance constant and tensile properties are also good. In contrast,
Comparative Examples 1 and 2, which had a single insulating layer, and Comparative Example 3, which had a relatively small difference in hardness between two insulating layers, both had cracks due to the heat added to the self-radial winding.

Therefore, on the stranded wire conductor 1, two kinds of ultraviolet curable resin compositions having a relatively large difference in hardness are used, and the first insulating layer 2 made of an ultraviolet curable resin composition having a small hardness is formed as an inner layer.
and a second layer of ultraviolet curable resin composition with high hardness in the outer layer.
By forming the insulating layer 3 and configuring the insulated wire 4,
It is possible to prevent cracks and cracks from occurring due to the self-diameter winding of the insulated wire 4 and the heat added to the self-diameter winding.

In this embodiment, the case where the stranded wire conductor 1 is coated with the insulating layers 2 and 3 has been described, but the conductor structure is not limited to stranded wires, and as shown in FIG. Even if a plurality of layers (two layers in the illustrated example) of insulating layers 5 and 6 are formed by coating ultraviolet curable resin compositions with different hardnesses, cracks and cracks due to self-radial winding and self-radial winding additional heat may occur. It is possible to prevent the occurrence of cracks. Further, a cable can also be manufactured using the insulated wire according to the present invention, and for example, as shown in FIG. 3, it is possible to manufacture a cable in which an insulated wire 4 is accommodated within a sheath 7. In FIG. 3, 8 indicates a space or an intervening filling.

[0031]

[Effects of the Invention] As explained above, according to the present invention,
Since the conductor is coated with multiple layers of ultraviolet curable resin compositions having different hardnesses, it exhibits an excellent effect of preventing the occurrence of cracks and cracks during bending and winding, especially during heating during winding.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of an insulated wire of the present invention.

FIG. 2 is a cross-sectional view showing another example of the insulated wire of the present invention.

FIG. 3 is a cross-sectional view showing an example of a cable using the insulated wire of the present invention.

[Explanation of symbols]

1 Conductor 2 First insulating layer 3 Second insulating layer

Claims (1)

[Claims] 1. An insulated wire characterized in that a conductor is coated with multiple layers of ultraviolet curable resin compositions having different hardnesses.