WO2009123279A1 - Insulated wire, coil using the same, and motor - Google Patents

Abstract

An insulated wire includes a conductor, a foundation layer covering the conductor, and an insulated layer formed on the foundation layer. The foundation layer is configured with a hardening body of a resin composition including a heat curing resin having an epoxy resin, and a reactive functional group. The heat curing resin includes 1 to 10 parts by mass with respect to 100 parts by mass of the epoxy resin. Further, the heat curing resin preferably includes 5 to 30 parts by moss of blocked isocyanate with respect to 100 parts by mass of the epoxy resin.

Description

Insulated wire, coil using the insulated wire, and motor

[Technical Field] The present invention relates to an insulated wire suitably used for an electric device such as an air conditioner or a refrigerator using a refrigerant, a compressor, a coil using the insulated wire, and a motor.

Insulated wires are used in various modes depending on the type of electrical equipment. For this reason, the insulating coating is required to have excellent adhesion so as to ensure insulation in various specifications. For example, it is required that the film does not peel off even against mechanical and physical stimuli such as wear and scratches.

As an insulating film having excellent adhesion, insulation, and mechanical strength, for example, Japanese Patent Application Laid-Open No. 2007-287399 (Patent Document 1) proposes an insulated wire having a two-layered insulating film. According to the configuration disclosed in this document, the first insulating layer is made of polyesterimide, and the second insulating layer is made of polyamideimide.

By the way, for electrical products such as air conditioners and refrigerators in which refrigerant is used, especially for insulated wires used in compressors, excellent adhesion to mechanical and physical stimuli such as processing and friction is not sufficient.

For example, an air conditioner compressor that is used in summer and not used in winter resumes operation after it has been idle for several months. In an insulated wire exposed to a refrigerant atmosphere, a refrigerant such as Freon that has adhered to the insulating coating penetrates into the coating during the resting state. When the temperature around the insulated wire becomes high as a result of restarting the equipment, the expanded and vaporized refrigerant pushes the coating. For this reason, a state where the insulating coating is foamed, that is, a blister occurs. Such a foaming phenomenon may also occur in a film having high adhesion to mechanical and physical stimuli. For this reason, it is not possible to determine whether or not an insulated wire can be used only by simple adhesion evaluation.

Polyesterimide resin insulation films are excellent in solvent resistance and have few problems of blistering, so they are used as insulation wire films for air conditioners and air conditioners. However, in order to cope with the severe winding process and varnish impregnation treatment in recent years, demands for heat resistance and wear resistance are becoming stricter year by year. For this reason, it is necessary to comprehensively evaluate the wear resistance, heat resistance, adhesion, blister generation, etc., for the insulated wire coating used in air conditioners and compressors. Therefore, there is a need for an insulated wire that can satisfy these characteristics in a composite manner.
JP 2007-287399 A

An object of the present invention is to provide an insulated wire capable of suppressing the generation of blisters not only for adhesion to mechanical stimulation, but also when operation is resumed after being exposed to a refrigerant for a long period of time.
The present applicant has found that an insulated wire using a cured product of an epoxy resin as a primer layer is superior in adhesion after heating and wear resistance as compared to an esterimide insulating coating, and applied for a patent (Japanese Patent Application No. 2007-). 266405). The present applicant has further studied and completed the present invention so that the generation of blisters can be suppressed.

In order to solve the above problems, according to a first aspect of the present invention, there is provided: a conductor; an underlayer covering the conductor; and an insulating layer formed on the underlayer, the underlayer comprising an epoxy resin, and An insulated wire composed of a cured body of a resin composition containing a thermosetting resin having a reactive functional group is provided. The thermosetting resin is contained in an amount of 1 to 10 parts by mass per 100 parts by mass of the epoxy resin.

In the above insulated wire, it is preferable that 5 to 30 parts by mass of blocked isocyanate is further contained per 100 parts by mass of the epoxy resin.
In the above insulated wire, the reactive functional group is preferably a methylol group.

In the above insulated wire, the thermosetting resin is preferably a phenol resin and / or an amino resin.
In the above insulated wire, the thermosetting resin is preferably a phenol resin.

In the above insulated wire, the thermosetting resin is preferably a xylene resin having a number average molecular weight of 100 to 3000.
In the above insulated wire, the epoxy resin is preferably a phenoxy resin.

In the above insulated wire, the insulating layer is preferably made of a polyesterimide resin.
In the above insulated wire, it is preferable that a lubricating overcoat layer is further formed on the insulating layer.

In order to solve the above problems, according to a second aspect of the present invention, there is provided a coil formed by winding the insulated wire.
In order to solve the above problems, according to a third aspect of the present invention, a motor having the above coil is provided.

Hereinafter, embodiments of the present invention will be described. The embodiments disclosed below are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

The insulated wire of the present invention includes a conductor, a base layer that covers the conductor, and an insulating layer formed on the base layer. The underlayer is made of a cured product of a resin composition containing an epoxy resin and a thermosetting resin having a reactive functional group.
〔conductor〕
A metal conductor such as a copper wire or an aluminum wire is used as the conductor.
[Underlayer]
The underlayer is made of a cured product of a resin composition containing an epoxy resin and a thermosetting resin having a reactive functional group. More preferably, the underlayer is made of a cured product of a resin composition containing a blocked isocyanate.
<Epoxy resin>
Examples of the epoxy resin used in the present invention include an epoxy resin produced from bisphenol and epihalohydrin, and an epoxy resin obtained by addition polymerization reaction of a phenol epoxy resin and bisphenol. These may be used alone or in combination of two or more. Among these, an epoxy resin produced from bisphenol and epihalohydrin is preferable, and a phenoxy resin having a large molecular weight is more preferable.

Examples of bisphenol include 2,2-bis (4-hydroxyphenyl) methane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) sulfide, and 2,2-bis. (4-Hydroxyphenyl) sulfone, 3,4,5,6-dibenzo-1,2-oxaphosphan-2-oxide hydroquinone and the like. These may be used alone or in combination of two or more. A preferred representative example of epihalohydrin is epichlorohydrin.

Suitable epoxy resins produced from bisphenol and epihalohydrin include, for example, bisphenol A modified phenoxy resin produced from bisphenol A and epihalohydrin, bisphenol S modified phenoxy resin produced from bisphenol S and epihalohydrin, and the like. . These phenoxy resins are all commercially available compounds, and specific examples thereof include product numbers YP-50, YP50S, YP-55, YP-70, and YPS007A30A manufactured by Tohto Kasei Co., Ltd. . The epoxy resin of this invention is not limited to said illustration.

The weight average molecular weight of the epoxy resin used in the present invention is not particularly limited, but is preferably 30,000 to 100,000, more preferably 50,000 to 80,000 from the viewpoint of improving heat resistance and adhesion.
<Heat-curing resin>
The thermosetting resin used for the underlayer of the present invention is a thermosetting resin that has a reactive functional group such as a hydroxyl group such as an amino group or a methylol group and can be cured by heating. Specifically, phenol resins obtained by reaction of phenols with aldehydes, amino resins obtained by condensation of amino group-containing compounds and formaldehyde, or mixed resins thereof are used.

Examples of amino group-containing compounds used for the synthesis of amino resins include urea, alkylurea, melamine, acetoguanamine, aniline, benzoguanamine and the like. Accordingly, the amino resin used in the present invention is a condensate of these amino group-containing compounds and formaldehyde, or an alcohol-modified resin thereof, and examples thereof include urea resins, melamine resins, guanamine resins, urea-melamine resins, and the like. .

As such an amino resin, a commercially available product may be used. Specifically, Uban 10S-60, 10R, 20SB, 20SE-60, 20HS, 21HV, 21R, 22R, 22R-60 from Mitsui Chemicals, Inc. may be used. 120, 122, 220, 134, 135, 136, 60R, 62, 69-1, 163, 164, 165, 805, 91-55; Cymel 300, 301, 303, 325, 350, Nippon Cytec Industries, Ltd. 370, 1116, 1130, 1123, 1125; DIC Corporation Becamine P-138, P-196-M, G-1800, G-1850, Super Becamine OD-L-131-60, L-806, J- 820-60, L-109-65, L-117-60, L-127-60, G-821-60 L-101-60, 47-508-60, L-116-70, L-118-60, L-121-60, L-120-60, TD-139, 17-590, L-105-60, TD-126, P-198.

Such an amino resin has an alcoholic hydroxyl group or amino group as a reactive functional group at the end of the resin by a methylolation reaction, and can be cured by normal temperature to heating.

When an amino resin having a reactive hydroxyl group such as a methylol group contains an epoxy resin or a blocked isocyanate by heating, it is considered that it can further react with an isocyanate group to form a crosslinked cured product. This is considered to be useful for the modification of the epoxy resin. In particular, the occurrence of blistering at a high temperature, which was a weak point of phenoxy resin, can be suppressed. In curing the epoxy resin, it is considered that the penetration of the refrigerant can be prevented by forming a cured body film having a crosslinked structure in which an amino resin is also involved. In addition, it is considered that, as for the permeated refrigerant, blistering can be suppressed as a result by preventing swelling of the film due to vaporization of the refrigerant and preventing the refrigerant from escaping.

Examples of phenols used for the synthesis of phenol resins include phenols, alkylphenols such as cresol, xylenol and isopropylphenol; divalent phenols such as resorcin; and vinylphenols such as p-vinylphenol. Two or more kinds may be used in combination. Examples of aldehydes used in the synthesis of phenol resins include aldehyde group-containing compounds such as acetaldehyde and furfural in addition to formaldehyde, and these may be used in combination of two or more. Depending on the types of phenols and aldehydes used, phenol resins are known as phenol resins, xylene resins, resorcin resins, resorcin-modified phenol resins, cresol-modified phenol resins, alkylphenol-modified resins, and the like.

Such phenol resins are generally classified into a novolak type synthesized using an acid catalyst and a resol type synthesized using an alkali catalyst. In the present invention, a resol type phenolic resin having a reactive hydroxyl group, particularly a methylol group at the resin chain end is preferably used.

Commercially available products may be used as the phenolic resins, for example, Sumikanol 610 from Taoka Chemical Co., Ltd .; Tamanoru 1010R, Tamanoru 100S, Tamanoru 510, Tamanoru 7509, Tamanoru 7705 from Arakawa Chemical Industries, Ltd .; Showa Polymer Shounol CKM-1634, 1636, 1737, 1282, 904, 907, 908, 983, 2400, 941, 2103, 2432, 5254, BKM-2620, BRP-5904, RM-0909, BLS-2030 3574, 3122, 362, 356, 3135, CLS-3940, 3950, BRS-324, 621, BLL-3085, BRL-113, 114, 117, 134, 274, 2584, 112A, 120Z, CKS-3898; Dee Chemical Co., Ltd. SP-460B, SP103H, HRJ-1367; Gunei Chemical Industry Co., Ltd. cash register top PL2211, Sumitomo Bakelite Co., Ltd. PR-HF-3, PR-53194, PR-53195; PR1440, Nikanol L, Nikanol P100; priorphen 5010, 503 and TD-447 manufactured by DIC Corporation.

The above phenol resins are liquid resins at room temperature and can be cured by heating. In addition, phenolic resins have an alcoholic hydroxyl group such as methylol as a reactive functional group. From this, it is considered that the phenol resins are useful for the modification of the epoxy resin by reacting with the epoxy resin contained in the varnish and further with the isocyanate to form a crosslinked cured product. That is, as with amino resins, it is possible to suppress the occurrence of blistering at high temperatures, which was a weak point of phenoxy resins. Furthermore, phenol resins can effectively suppress the occurrence of blisters without impairing the excellent wear resistance, softening resistance, and high-temperature adhesion of phenoxy resins.

The above amino resins and phenol resins may be used singly or in combination of two or more, or may be used by blending amino resin and phenol resins. Phenol resins are preferable.

Furthermore, among phenolic resins, liquid modified xylene / formaldehyde resin is used. The liquid modified xylene / formaldehyde resin can be obtained by adding alcohols, phenols, and the like to the xylene / formaldehyde resin obtained by the reaction of xylene and formaldehyde in the presence of an acidic catalyst. As the liquid modified xylene / formaldehyde resin, specifically, an oligomer having a methylol group as a reactive hydroxyl group is preferably used which is a resol type resin containing a metaxylene / mesitylene skeleton. The number average molecular weight of the oligomer is preferably 100 to 3000, more preferably about 200 to 1500. Further, it is preferably a liquid having a viscosity of 20 to 15000 centipoise (25 ° C.), more preferably 30 to 5000 centipoise (25 ° C.), and still more preferably 30 to 1000 so that the compatibility with the epoxy resin is excellent. A centipoise, particularly preferably 30 to 500 centipoise.

The thermosetting resin having such a reactive functional group is contained in an amount of 1 to 10 parts by weight, preferably 2 to 8 parts by weight, per 100 parts by weight of the epoxy resin. When the content of the thermosetting tree is too large, the crosslink density of the film becomes too high, and the flexibility is lowered. For this reason, the elongation of the film is lowered, and as a result, the adhesion during processing and use is lowered. On the other hand, when the content of the thermosetting tree is too small, it is difficult to obtain the effect of adding the thermosetting resin, that is, the effect of suppressing the generation of blisters.
<Block isocyanate>
The underlayer resin composition preferably contains a blocked isocyanate. The blocked isocyanate mainly acts as a curing agent for the epoxy resin.

Examples of the isocyanate compounds include aromatic diisocyanates such as tolylene diisocyanate (TDI), p-phenylene diisocyanate, and naphthalene diisocyanate; hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexane diisocyanate, lysine diisocyanate, and the like. Aliphatic diisocyanates having 3 to 12 carbon atoms: 1,4-cyclohexane diisocyanate (CDI), isophorone diisocyanate (IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI), methylcyclohexane diisocyanate, isopropylidene Dicyclohexyl-4,4'-diisocyanate, 1,3-diisocyanatomerylcyclohexane (hydrogenated XDI), hydrogenated TDI, 2,5-bis (a Salicyclic diisocyanates having 5 to 18 carbon atoms such as sinatomethyl) -bicyclo [2.2.1] heptane, 2,6-bis (isosinatomethyl) -bicyclo [2.2.1] heptane; (XDI), aliphatic diisocyanates having an aromatic ring such as tetramethylxylylene diisocyanate (TMXDI); modified products of these diisocyanates, etc., which may be used alone or in combination of two or more. May be used.

Commercially available block isocyanate curing agents may be used, such as CT stable, BL-3175, TPLS-2759, BL-4165, Sumitomo Biurethane Co., Ltd., MS-50 manufactured by Nippon Polyurethane Industry Co., Ltd. Can be used.

Such a blocked isocyanate compound is preferably used at a ratio of 5 to 30 parts by mass per 100 parts by mass of the epoxy resin. The blocked isocyanate compound forms a bond with an epoxy resin curing agent, and also with a thermosetting resin having a reactive functional group. These reactions can provide a highly three-dimensional reticulated cured film. Therefore, it is possible to increase the heat resistance, wear resistance, softening resistance, and adhesion of the base layer based on the epoxy resin, and thus the coating, and to suppress the generation of blisters.

In the resin composition constituting the base layer of the insulated wire of the present invention, in addition to the epoxy resin, thermosetting resin, and blocked isocyanate, as long as the purpose of the present invention is not impaired, for example, silica, Fillers such as alumina, magnesium oxide, beryllium oxide, silicon carbide, titanium carbide, tungsten carbide, boron nitride, silicon nitride; to improve insulating paint curability and fluidity, for example, tetraisopropyl titanate, tetrabutyl titanate, tetra Additives such as titanium-based zinc naphthenates such as hexyl titanate and zinc-based compounds such as zinc octenoate; antioxidants; curability improvers; leveling agents;

A resin composition containing the above components is diluted with an organic solvent to prepare a coating, and the coating applied to the surface of the conductor is heated and cured to form a base layer. The heating temperature is not particularly limited, but is preferably about 100 to 250 ° C.

Examples of the organic solvent used for preparing the paint include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, hexaethyl phosphate triamide, and γ-butyrolactone. Polar organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketones; esters such as methyl acetate, ethyl acetate, butyl acetate and diethyl oxalate; diethyl esters, ethylene glycol dimethyl ether, diethylene glycol monomethyl Ethers, ethers such as ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol methyl ether, tetrahydrofuran; hexane, heptane, benzene, tolue Hydrocarbon compounds such as xylene, halogenated hydrocarbon compounds such as dichloromethane and chlorobenzene, phenols such as cresol and chlorophenol, and tertiary amines such as pyridine. These organic solvents are used alone. Or two or more of them may be used in combination.

The thickness of the underlayer is not particularly limited, but is preferably 1.0 to 10 μm, more preferably 1.0 to 5 μm from the viewpoint of improving the adhesion between the insulating coating and the conductor.
[Insulating layer]
As the insulating layer, resins, polyester imides, polyimides, polyamide imides, and the like conventionally used as insulating coatings can be used. Of these, polyester imide is preferable.

For example, the insulating layer may be formed by dissolving a resin composition containing the additives listed in the composition for the underlayer in an organic solvent in a polyester imide resin, as long as the object of the present invention is not impaired. It can be formed by adjusting the coating liquid and applying the coating liquid on the underlayer. Or you may form an insulating layer by drying, after immersing the electric wire in which the base layer was formed in the coating liquid for insulating films.

The insulating layer may be a single layer or two or more layers. When composed of two or more layers, different resins, for example, a polyesterimide layer and a polyamideimide layer may be combined.

The thickness of the insulating layer is preferably 1 to 100 μm, more preferably 10 to 50 μm, from the viewpoint of protecting the conductor. This is because if the insulating coating becomes too thick, the outer diameter of the insulated wire increases, and as a result, the space factor of the coil wound around the insulated wire tends to decrease.
(Lubricity overcoat layer)
In the insulated wire of the present invention, it is preferable that a lubricating overcoat layer is further formed on the insulating layer. Covering the insulating layer with a resin having lubricity is preferable because friction between electric wires generated during compression processing for increasing coil winding and space factor is reduced.

The resin constituting the lubricity overcoat layer may be any resin that has lubricity, for example, paraffins such as liquid paraffin and solid paraffin, various waxes, polyethylene, fluororesin, silicone resin and other lubricants as binders. Examples thereof include those bound with a resin. Preferably, an amidoimide resin imparted with lubricity by adding paraffin or wax is used. The lubricity overcoat layer may be formed not only by the resin having the above-mentioned lubricity but also by applying a non-volatile lubricant.

The lubricating overcoat layer may be one layer or two or more layers. Further, a lubricity overcoat layer may be formed by applying a non-lubricating lubricant on the resin layer having lubricity and further on the resin layer.

The thickness of the lubricating overcoat layer is not particularly limited, but may be a thickness sufficient to reduce friction and wear with the surrounding electric wires when the insulated electric wires are formed in a coil shape. Specifically, the thickness of the lubricating overcoat layer is preferably 0.5 to 10 μm, more preferably 1 to 5 μm.

The insulated wire of the present invention having the configuration as described above has not only excellent adhesion to mechanical stimulation but also when the insulating film is exposed to a refrigerant atmosphere, it is further operated for a certain period and for a certain period. The occurrence of blisters is also suppressed when the pauses are repeated alternately.

The best mode for carrying out the present invention will be described with reference to examples. The examples do not limit the scope of the invention.
[Measurement evaluation method]
First, the evaluation method performed in this example will be described.
(1) Flexible The insulated wire was stretched by 30% with respect to the initial length, and after stretching, it was tested according to JIS C3003 7.1.1 flexibility test. Specifically, after winding the electric wire 10 times so that the electric wire and the electric wire were in contact with each other along a round bar having a self-diameter of the insulated wire, the presence or absence of cracks was observed and the number of cracks was counted.
(2) Dielectric breakdown voltage (kV)
It measured based on JIS C3003 10.2.2. Specifically, the electric wire was immersed for 25 cm in a glycerin / saturated NaCl water = 85/15 solution. After immersing a copper plate as a counter electrode, the wire conductor was a positive electrode and the copper plate was a negative electrode. Then, an alternating voltage having a waveform close to a sine wave of 50 Hz was added, the voltage was increased at a speed of 500 V / s, and the voltage when current flowed was measured.
(3) Friction resistance (gf)
JIS C3003 9. The unidirectional wear test was conducted. Specifically, the unidirectional wear of six samples was measured at room temperature. Here, first, while applying a load to the needle attached to the friction head and continuously increasing the load, the surface of the insulated wire on the test table was rubbed with the needle of the friction head. Next, the load when the film was broken by the friction between the needle and the insulated wire and conduction was generated between the needle and the conductor was determined as the breaking load. And the average value was calculated | required.
(4) Adhesion i) Initial adhesion In accordance with JIS C3003 “8.1a) Rapid extension”, the produced insulated wire was abruptly stretched and cut, and the exposed conductor was peeled off at the cut portion. The length was measured. At this time, the average value when measured at two locations was determined as the conductor exposure average (mm). In addition, it shows that the coating layer is not peeled in a cut surface, and it shows that it is excellent in adhesiveness, so that the measured value of the length of the exposed conductor is small.

ii) Adhesiveness after heat treatment After the insulated wire was heated at 180 ° C. for 6 hours (heating condition 1) or 160 ° C. for 6 hours (heating condition 2), it was exposed according to the initial adhesiveness of i) above. The length (mm) of the conductor was measured.
(5) Blister after refrigerant treatment The insulated wire was immersed in refrigerant R22 (Daikin 22 of Daikin Industries, Ltd.) (85 ° C., 42 kg / cm 2) for 96 hours, then taken out and rapidly removed at a predetermined temperature (120 ° C., 130 To 140 ° C.) and the foamed state of the insulated wire surface was confirmed. The case where foaming was not recognized was defined as “OK”, and the case where foaming was observed was defined as “blister generation”.
(6) Softening resistance The softening temperature (° C.) was measured according to JIS C3003 “11.1A”. Specifically, in the softening resistance test, first, two insulated wires were prepared, and both insulated wires were set so as to cross each other on a metal block preheated to a temperature specified in the individual standard. After elapse of a predetermined time, a load was applied to the intersecting portion of both insulated wires using a piston, and a test voltage was immediately applied to the upper and lower insulated wires.
[Insulated wire No. Production of 1-8]
By coating a copper wire having a diameter of 0.897 to 0.898 mm with a layer structure (first to fourth layers in order from the copper wire) having a resin as a main component as shown in Table 1, the finished outer diameter is 0.966. Insulated wire no. 1 to 8 were produced. No. In Nos. 3 to 8, phenoxy resin was used as the base resin for the first layer, and a resin composition to which a xylene / formaldehyde resin and / or a curing agent (block isocyanate) was added as shown in Table 2 was used.

Specific materials used are as follows.
(1) Esterimide resin (EI)
A commercially available polyesterimide (manufactured by Hitachi Chemical Co., Ltd., trade name: Isomid 40SM-45) was used.
(2) Close contact ester imide resin (Close contact EI)
EH402-45No. 3 (manufactured by Dainichi Seika Co., Ltd.) was used.
(3) Amidoimide resin (AI)
HI-406E-34 (trade name of Hitachi Chemical Co., Ltd.) was used.
(4) Lubricating amidoimide resin (lubricating AI)
In a 1 L flask equipped with a thermometer, a cooling pipe, a calcium chloride-filled pipe, a stirrer, and a nitrogen blowing pipe, while flowing 150 mL of nitrogen gas from the nitrogen blowing pipe per minute, 176.9 g of trimellitic anhydride, 1.95 g of trimellitic acid and 232.2 g of methylene diisocyanate (trade name: Coronate PH manufactured by Mitsui Takeda Chemical Co., Ltd.) were added.

Next, 536 g of N-methyl-2-pyrrolidone as a solvent was added to the flask, heated at 80 ° C. for 3 hours while stirring with a stirrer, and then the temperature in the system was increased to 120 ° C. over about 4 hours. Warm and heat at the same temperature for 3 hours. Thereafter, the heating was stopped, and 134 g of xylene was added to the flask to dilute the content liquid, followed by cooling to obtain a general-purpose amideimide resin (AI) having a nonvolatile content of 35% by mass. Lubricating amideimide resin (lubricating AI) was obtained by mixing AI and polyethylene wax at a ratio of 1.5 parts by weight of polyethylene wax with respect to 100 parts by weight of solid content of this general-purpose amideimide resin (AI). .
(5) Phenoxy resin (PH)
As an epoxy resin, a bisphenol A type phenoxy resin [Tobu Kasei Co., Ltd., product name: YP-50, a solution of phenoxy resin dissolved in cresol / cyclohexanone (solid content: 27 mass%)] was used.
(6) Xylene / formaldehyde resin Nikanol PR-1440 (trade name) manufactured by Fudou Co., Ltd. was used. This is a solution (resin content: 52 mass%) of a resol type modified xylene resin (number average molecular weight 911) represented by the following formula dissolved in n-butanol, and the viscosity is 100 to 300 centipoise (20 ° C.). is there.

(7) Block isocyanate Block isocyanate (MS-50: trade name) manufactured by Nippon Polyurethane Industry Co., Ltd. was used. This blocked isocyanate is a bifunctional type having two isocyanate groups in one molecule.

First, the initial adhesion of each of the produced insulated wires was measured according to the above evaluation method. Next, the adhesion after heat treatment (heating condition 1: 180 ° C. × 6 hours) was measured. Furthermore, the heat-treated electric wires were examined for flexibility, dielectric breakdown voltage, abrasion resistance, softening resistance, and occurrence of blisters after the refrigerant treatment according to the above evaluation methods. The results are shown in Table 2.

No. The base resin of the base layer is phenoxy resin. In Nos. 3 to 8, excellent adhesion could be secured even after the heat treatment. No. 3 to 8, the initial adhesion is inferior to that of the ester imide resin (No. 1, 2), but after the heat treatment, the adhesion is superior to the coating having the base layer based on the ester imide resin. It was. In addition, in the base layer (No. 3 to 8) based on phenoxy resin, a film having excellent friction resistance and excellent mechanical strength was obtained.

No. 3 and no. Compared with 4-8, even if the adhesion after rapid extension is similar, in the case of an underlayer that does not contain xylene / formaldehyde resin (No. 3), if it is exposed to high temperatures after refrigerant treatment A blister occurred. On the other hand, in the case of the underlayer containing xylene / formaldehyde resin (No. 4 to 8), no blister was generated. In addition, the inclusion of xylene / formaldehyde resin reduced the number of cracks after the flexibility test to zero and improved the flexibility.

No. 4-7 and no. From the comparison with 8, the softening temperature improved in the phenoxy resin composition containing the curing agent. This is presumably because the resin composition was three-dimensionally reticulated and a denser film was obtained. Moreover, such a tendency was so large that the addition amount of a hardening | curing agent was large.
[Insulated wire No. Production of 11 to 24]
As shown in Table 3, instead of xylene / formaldehyde resin, apply a coating for the underlayer using other phenolic resins (F1 to F6) and / or amino resins (A1 or A2) and heat at 400 ° C. It hardened | cured and formed the base layer (1st layer). Next, no. The second layer, the third layer, and the fourth layer are formed in the same manner as in FIG. 11 to 19 were created.

Furthermore, except that block isocyanate was changed to “Death Module CT” of Bayer, No. In the same manner as in No. 11 or 13, each insulated wire No. 20 and 21 were produced. “Desmodur CT” is a trifunctional type composition having three isocyanate groups in one molecule, and is represented as “CT” in Table 3.

For reference, an insulated wire having a base layer formed using a phenoxy resin (No. 22), a high adhesion ester imide resin (No. 23), and a general-purpose ester imide resin (No. 24) was prepared.

Created insulated wire No. With respect to 11 to 24, abrasion resistance, dielectric breakdown voltage, softening resistance, adhesion after heating (heating condition 2: 160 ° C. × 6 hours), and prestar were measured based on the above evaluation methods. The results are shown in Table 3.

The amino resins and phenol resins in Table 3 are as follows.
A1: Cymel 370 from Nippon Cytec Industries, Ltd.
A2: Super Becamine OD-L-131-60 from DIC Corporation
F1: Sumikanoru 610 from Taoka Chemical Co., Ltd.
F2: CKS3898 of Showa Polymer Co., Ltd.
F3: PRIOFEN 5010 from DIC Corporation
F4: Gunei Chemical Industry Co., Ltd. cash register top PL2211
F5: Tamanol 100S from Arakawa Chemical Co., Ltd.
F6: Sumitomo Bakelite Co., Ltd. PR-53194

When a general-purpose ester imide resin was used as the base resin for the underlayer (No. 23), the wear resistance was inferior, and when a high adhesion ester imide resin was used (No. 24), the high-temperature adhesion was inferior. . In contrast, when a phenoxy resin was used as the base resin (No. 22), the results of abrasion resistance, softening resistance, and high-temperature adhesion were all good, but blisters were generated. However, when amino resins (No. 11, 12, 20) or phenol resins (No. 13 to 18, 21) are added, and when amino resins and phenol resins are blended (No. 19), In all cases, no blistering occurred. It was confirmed that the occurrence of blistering, which is a weak point of phenoxy resin, can be suppressed for amino resins and other phenol resins as well as xylene / formaldehyde resins.

However, when amino resin is used (No. 11, 12, 19, 20), when phenolic resins are used (No. 13 to 18), it adheres at a higher temperature than when phenoxy resin is used alone (No. 22). A tendency to be slightly inferior was observed. And No. 11 and no. From the comparison of 20, even if it changed to trifunctional type as blocked isocyanate, the effect which suppresses the fall of high temperature adhesiveness was hardly recognized. From these facts, it is understood that phenol resins are more effective in preventing blister generation of phenoxy resin.

The insulated wire of the present invention has improved mechanical strength and high adhesion to mechanical stimulation as compared to conventional wires, and can suppress the generation of blisters even in an environment exposed to a refrigerant atmosphere. . For this reason, it is particularly useful as an insulated wire such as a coil for an air conditioner compressor, which requires processing resistance, strength, and refrigerant resistance.

Claims (11)

1. A resin composition comprising: a conductor; a base layer covering the conductor; and an insulating layer formed on the base layer, wherein the base layer includes an epoxy resin and a thermosetting resin having a reactive functional group An insulated wire composed of a cured body of
   The insulated wire according to claim 1, wherein the thermosetting resin is contained in an amount of 1 to 10 parts by mass per 100 parts by mass of the epoxy resin.
2. The insulated wire according to claim 1, further comprising 5 to 30 parts by mass of blocked isocyanate per 100 parts by mass of the epoxy resin.
3. The insulated wire according to claim 1 or 2, wherein the reactive functional group is a methylol group.
4. The insulated wire according to any one of claims 1 to 3, wherein the thermosetting resin is a phenol resin and / or an amino resin.
5. The insulated wire according to claim 4, wherein the thermosetting resin is a phenol resin.
6. The insulated wire according to claim 5, wherein the thermosetting resin is a xylene resin having a number average molecular weight of 100 to 3000.
7. The insulated wire according to any one of claims 1 to 6, wherein the epoxy resin is a phenoxy resin.
8. The insulated wire according to any one of claims 1 to 7, wherein the insulating layer is made of a polyesterimide resin.
9. The insulated wire according to any one of claims 1 to 8, wherein a lubricating overcoat layer is further formed on the insulating layer.
10. A coil obtained by winding the insulated wire according to any one of claims 1 to 9.
11. A motor having the coil according to claim 10.