JP2002145996A - Thermosetting resin composition and insulated coil using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermosetting resin composition having good curability and good storage stability, and to provide an insulated coil which uses the thermosetting resin composition, has high reliability, and can be produced at a low cost and in good production workability. SOLUTION: This thermosetting resin composition comprising (A) an epoxy resin having two or more epoxy groups in the molecule, (B) a liquid polycarboxylic acid anhydride, and (C) a curing catalyst is characterized in that the content of water contained at the compounding early time is <=800 ppm. The insulated coil comprising a coil conductor and an insulating layer which is obtained by winding the coil conductor which an insulating tape prepared by adhering an insulating material to a reinforcing material with a binder resin, impregnating the obtained insulating tape layer with the thermosetting resin composition, and then curing the impregnated resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to, for example, an insulating coil for a rotating machine for a generator, a rotating machine for general industry or a rotating machine for a vehicle, and an insulating coil for a rotating electric machine manufactured by a single impregnation method or a full impregnation method. The present invention relates to a thermosetting resin composition and an insulating coil using the thermosetting resin composition.

[0002]

2. Description of the Related Art A rotating machine for a generator, a rotating machine for general industry, or a rotating machine for a vehicle is required to have a higher voltage and a smaller size, and an insulating coil incorporated in the rotating machine has withstand voltage and heat resistance. What is required is excellent.

[0003] A usual insulated coil is formed by winding an insulating tape on a coil conductor formed in a predetermined shape by combining wires having an appropriate insulation coating, and drying this by vacuum drying in an impregnation tank. After removing volatile components and air from the product, it is manufactured by injecting an impregnated resin consisting of a thermosetting resin, further pressurizing and infiltrating the wound layer, taking out and curing it, and forming an insulating layer. Was.

[0004] Here, the insulation treatment method of the insulation coil is performed by impregnating the coil with a resin alone, heating and hardening the coil by a heat press, and then incorporating the coil into a stator core slot and connecting the coil before the resin impregnation. There is a full impregnation method in which a stator core slot is assembled and connected and then impregnated collectively. The simple impregnation method has an advantage that a dense insulating layer can be formed. On the other hand, the total impregnation method has the following advantages. (1) Since only one impregnation and curing step is required, the processing cost can be reduced. (2) Since the coil and the stator core are firmly fixed by the impregnating resin, the mechanical rigidity of the entire winding is improved. (3) Since the impregnating resin is filled between the coil and the stator core slot, the thermal resistance during this period is smaller than that of the simple impregnation method. The temperature rise can be suppressed more efficiently than in the simple impregnation method. For this reason, in the past, small impregnated coils have been all impregnated, and large insulated coils have been treated as a single impregnated coil. It is desired to.

On the other hand, as the impregnating resin, a low-viscosity thermosetting resin such as unsaturated polyester, epoxy resin or silicone resin is used, and the epoxy resin having excellent electrical and mechanical properties of the cured product is used as an acid resin. Resin systems that cure with anhydrides are commonly used.

[0006] The epoxy resin-acid anhydride-cured impregnated resin is generally used by blending a curing accelerator because of its slow curing speed. However, when a curing accelerator is added to the impregnated resin, there is a problem that the increase in the resin viscosity is accelerated and the pot life is shortened. In particular, in the full impregnation method, the temperature of the impregnated resin is increased to improve the impregnation property of the resin, and the viscosity of the impregnated resin is reduced to impregnate the insulating layer. Therefore, the resin is stored in a heated state during the impregnation. Therefore, there is a problem that the pot life is further shortened.

In addition, in the impregnated resin of the epoxy resin-acid anhydride cured system, the acid anhydride opens a ring when the impregnated resin absorbs moisture, and the free acid (carboxylic acid) is generated, whereby the epoxy resin and the free acid are separated. There is also a problem that the resin reacts and the viscosity of the resin increases quickly, so that the pot life is shortened. This increase in viscosity
This is a serious problem in the total impregnation method using a large amount of resin.

[0008] The resin impregnation of the insulating layer of the insulating coil is performed by immersing the insulating coil in an impregnation tank filled with the impregnating resin, and when the impregnation is completed, a new insulating coil is added.
Since the impregnated resin is used repeatedly, it is desired that the impregnated resin has a long pot life without a rise in viscosity during impregnation or storage.

Heretofore, in order to extend the pot life of the impregnated resin, the amount of the curing accelerator added to the impregnated resin has been reduced, or a new impregnated resin has been frequently added every time the impregnated resin thickens. . However, reducing the addition amount of the curing accelerator requires a long time to cure the impregnated resin, lowers the productivity of the insulating coil, and increases the manufacturing cost. In addition, complicated addition of a new impregnating resin also has a problem in that the productivity of the insulating coil is reduced and the manufacturing cost is increased.

[0010] A liquid epoxy resin composition which has good surface curability and curing of epoxy resin impregnated in details, has improved pot life and storage stability, and gives a cured product having an appropriate curing rate. 6-2
No. 7183, which contains (A) a liquid epoxy resin, (B) a liquid carboxylic anhydride, (C) a curing accelerator comprising a complex compound of boron trichloride, and (D) a microcapsule-type latent curing agent. Liquid epoxy resin compositions are disclosed.

However, the above publication has the following drawbacks because a microcapsule-type latent curing agent is used. (1) Since the microcapsule-type latent curing agent does not dissolve in the thermosetting resin composition composed of an epoxy resin and an acid anhydride, and becomes a dispersed state, it precipitates during storage. (2) The shell of the microcapsule is broken by mechanical shearing force such as stirring, and storage stability is reduced. (3) The shell of the microcapsule is dissolved by long-term storage, and storage stability is reduced. Further, neither the effect of moisture absorption on the pot life nor the use in insulating coils has been studied.

Further, as thermosetting epoxy resin systems having good reactivity / stability, JP-A-7-278269 discloses (a) at least one epoxy resin, and (b) at least one polycarboxylic anhydride. (C) a 1,4-diazabicyclo (2,2,2) octane or a 1,4-diazabicyclo (2,2,2) octane derivative substituted with an alkyl group having 1 to 4 carbon atoms as a curing accelerator; A thermosetting epoxy resin composition is disclosed in which the curing accelerator (c) is partially replaced by (d) a complex of a boron halide and an amine. However, the above publication does not discuss the curability and storage stability of the curing composition in the thin film portion. Further, no consideration has been given to the case where the coil is used for an insulating coil.

[0013]

That is, an epoxy resin
There was no thermosetting resin composition using a curing accelerator that uniformly dissolves in a thermosetting resin composition composed of an acid anhydride and having good curability and storage stability. In addition, there has been no insulating coil having high reliability, low cost, and good manufacturing workability using a thermosetting resin composition having good curability and storage stability.

The present invention has been made in order to solve such problems, and has as its object to obtain a thermosetting resin composition having good curability and storage stability.
It is another object of the present invention to obtain an insulated coil having high reliability, low cost, and good manufacturing workability. It is another object of the present invention to obtain an insulated coil manufactured by the total impregnation method, which has high reliability, is low in cost, and has good workability.

[0015]

The first thermosetting resin composition according to the present invention comprises (A) an epoxy resin having two or more epoxy groups in a molecule, (B) a liquid polycarboxylic anhydride. And an epoxy resin composition containing (C) a curing catalyst, wherein the amount of water contained in the composition at the initial stage of blending is 8
It is a thermosetting resin composition characterized by being at most 00 ppm.

In the second thermosetting resin composition according to the present invention, the curing catalyst comprises (D) a complex of tetraphenylborate and / or boron trichloride with an amine.

In the third thermosetting resin composition according to the present invention, the curing catalyst comprises (D) a complex of amine with tetraphenylborate and / or boron trichloride, and (E) a metal salt of an organic acid. Things.

In the first or second thermosetting resin composition, tetraphenylborate and / or a complex of boron trichloride and amine is contained in an amount of 0.005% of the entire resin composition.
~ 1.0 weight percent.

In the first or third thermosetting resin composition, a complex of amine with tetraphenylborate and / or boron trichloride may be contained in an amount of 0.005% of the entire resin composition.
To 1.0% by weight, and the organic acid metal salt comprises 0.005 to 1.0% by weight of the whole resin composition.

The fourth thermosetting resin composition according to the present invention is the same as the first, second or third thermosetting resin composition, wherein the amine is a quaternary salt in the salt of tetraphenylborate and amine. It consists of an amine compound, an imidazole compound or 1,8-diazabicyclo (5,4,0) undecene-7.

The fifth thermosetting resin composition according to the present invention is the same as the first, second or third thermosetting resin composition, wherein the amine is N, N in the complex of boron trichloride and amine. -A dimethyloctylamine complex.

A first insulating coil according to the present invention is obtained by winding a coil conductor and an insulating tape formed by bonding an insulating material to a reinforcing material with a binder resin, and impregnating with a thermosetting resin to cure the coil. In the insulating coil provided with an insulating layer, the thermosetting resin may be any one of the first, second, third, fourth through fifth
Is a thermosetting resin composition.

In a second insulating coil according to the present invention, an insulating layer formed by winding an insulating tape obtained by bonding an insulating material to a reinforcing material with a binder resin is provided on a coil conductor, and is housed in a stator core slot. A thermosetting resin is impregnated and cured together with the stator core, and is cured with the cured product of the thermosetting resin. The insulating coil is integrated with the stator core. 3, 4 to the fifth thermosetting resin composition.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The thermosetting resin composition of the present invention comprises (A) an epoxy resin having two or more epoxy groups in a molecule, (B) a liquid polycarboxylic anhydride, and (C) a curing catalyst. The composition has a water content of 800 ppm or less at the initial stage of blending, and has good curability and storage stability.

The insulated coil of the present invention comprises a coil conductor, an insulating tape formed by winding an insulating tape obtained by bonding an insulating material to a reinforcing material with a binder resin, impregnating with a thermosetting resin, and curing the coil. Insulation coil with thermosetting resin composition with good curability and storage stability with good impregnating resin, capable of dense insulation element formation, high reliability, low cost An insulating coil having good manufacturing workability can be obtained. Such an insulated coil is applied to insulation treatment of a single impregnation method.

Further, the insulating coil of the present invention is provided with an insulating layer in which an insulating tape formed by bonding an insulating material to a reinforcing material with a binder resin is wound around a coil conductor, and is housed in a stator core slot. An insulating coil that is impregnated and cured with a thermosetting resin together with the iron core, and is integrated with the stator core by a cured product of the thermosetting resin, and the impregnated resin has good curability and storage stability. It consists of a thermosetting resin composition. For this reason, the insulation treatment of the full impregnation method can simplify the process by impregnating the coil and shortening the thermosetting time, so that an insulated coil having high reliability, low cost, and good manufacturing workability can be obtained.

Hereinafter, the thermosetting resin composition and the insulating coil of the present invention will be described. The epoxy resin according to the present invention is not particularly limited as long as it contains two or more epoxy groups in the molecule. If such a compound, the cured product is excellent in heat resistance, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, diallyl bisphenol A type epoxy resin, diallyl bisphenol F type epoxy resin, Diallyl bisphenol AD epoxy resin, tetramethylbiphenol epoxy resin, biphenol epoxy resin, cyclopentadiene epoxy resin, terpene phenol novolak epoxy resin, tetrabromobisphenol A epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy Resin, triphenylmethane epoxy resin, cycloaliphatic epoxy resin, glycidyl ester epoxy resin, heterocyclic epoxy resin, etc. Mention may be made of mixtures thereof.

Of the above epoxy resins, it is desirable to use a liquid epoxy resin having a low viscosity from the viewpoint of impregnation. Further, from the viewpoint of storage stability, a low-viscosity liquid epoxy resin having no secondary hydroxyl group in the molecule, and a moisture absorption rate of 1000 pp
It is desirable to use a liquid epoxy resin of m or less. In particular, from the viewpoint of the moisture absorption of the epoxy resin, bisphenol A type epoxy resin or bisphenol F type epoxy resin having 95% or more of n = 0 obtained by molecular distillation or the like is more preferable.
dite MY 790-1 (manufactured by Bantico Co., Ltd.) and E1750 (manufactured by Yuka Shell Epoxy Co., Ltd.).

The liquid acid anhydride according to the present invention is not particularly limited as long as it is a liquid acid anhydride capable of undergoing a curing reaction with an epoxy resin. Examples of such a compound include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, and trialkyltetrahydrophthalic anhydride, and a single compound or a mixture thereof. From the viewpoint of storage stability, it is desirable to use a liquid acid anhydride having a free acid concentration (ring-opened dicarboxylic acid compound) of 1,000 ppm or less in the liquid acid anhydride. The compounding amount of the liquid polycarboxylic acid anhydride is a total equivalent of 1 to 1 of epoxy groups derived from an epoxy resin having two or more epoxy groups in a molecule.
Is preferably 0.7 to 1.2 equivalents. If it is less than 0.7 equivalent, the viscosity increases due to a decrease in the proportion of the acid anhydride as a low-viscosity component in the thermosetting resin composition, and the heat resistance and mechanical properties of the cured product are reduced. If it exceeds 1.2 equivalents, the heat resistance and mechanical properties of the cured product will be reduced.

In order to realize good storage stability, the thermosetting resin composition of the present invention desirably has a water content of 800 ppm or less in the resin composition at the initial stage of compounding.
pm or less is more preferable. When the water content in the thermosetting resin composition exceeds 800 ppm, the storage stability of the thermosetting resin composition is impaired. This is because the water in the thermosetting resin composition opens the ring of the liquid acid anhydride, and the generated free acid is
It is considered that storage stability is impaired by reacting with the epoxy resin to increase the molecular weight.

The curing accelerator according to the present invention preferably contains a tetraphenylborate salt and / or a boron trichloride complex and a metal salt of an organic acid. The epoxy resin-acid anhydride system has a problem that if the resin thickness is small, curing failure occurs. As a result of elucidation of the cause, in a portion where the resin thickness is thin, at the time of heating for curing, an acid anhydride having a low boiling point is volatilized, so that the balance of the mixing ratio of the epoxy resin and the acid anhydride in the resin composition is broken. I understand. In particular, in an epoxy resin-anhydride system containing a latent curing accelerator such as a tetraphenylborate salt or a boron trichloride complex, the accelerator is latent, so that the epoxy resin and the acid anhydride cannot be dissolved until a certain temperature. Most of the acid anhydride is volatilized in a region at or below the temperature at which the effect of the curing accelerator is exhibited during heating for curing without promoting the curing and curing failure is likely to occur. In order to prevent poor curing, it is necessary to sufficiently cure the epoxy resin remaining by volatilization of the acid anhydride as a curing agent alone.

The tetraphenylborate salt according to the present invention is not particularly limited as long as it has an effect of accelerating the reaction between the epoxy resin and the acid anhydride. For example, tetraphenyl borate salts such as quaternary amine compounds, imidazole compounds, phosphorus compounds, and heterocyclic compounds can be mentioned.

Examples of such compounds include 2-methylimidazolium tetraphenylborate, 2-ethyl-4
-Methylimidazolium tetraphenylborate, 2-
Phenylimidazolium tetraphenylborate, 1-
Benzyl-2-methylimidazolium tetraphenylborate, 1-benzyl-2-ethylimidazolium tetraphenylborate, 1-cyanoethyl-2-methylimidazolium tetraphenylborate, 1-cyanoethyl-2-ethyl-4-methylimidazolium Tetraphenylborate, 1-methyl-2-ethylimidazolium tetraphenylborate, or 1-isobutyl-2
Tetramethyl borate salts of imidazole compounds such as -methyl imidazolium tetraphenyl borate, tetramethyl ammonium tetraphenyl borate, tetraethyl ammonium tetraphenyl borate, tetrapropyl ammonium tetraphenyl borate, tetrabutyl ammonium tetraphenyl borate, trioctyl methyl ammonium tetraphenyl Borate, triurarylmethylammonium tetraphenylborate, benzyltriethylammonium tetraphenylborate, benzyltributylammonium tetraphenylborate, or tetraphenylborate salts of quaternary amine compounds such as phenyltrimethylammonium tetraphenylborate, tetrabutylphosphonium tetraphenylborate, Te Tetraphenylborate salts of phosphorus compounds such as laphenylphosphonium tetraphenylborate, tetratolylphosphonium tetraphenylborate or tetraoctylphosphonium tetraphenylborate; 1,8-diazabicyclo (5,4,0) undecenium tetraphenylborate; There are tetraphenylborate salts of heterocyclic compounds and the like, and single or mixtures thereof.

Of these, 1,8-diazabicyclo (5,4,0) undecenium tetraphenyl borate is preferred from the viewpoint of storage stability of the resin composition. Moreover, tetraphenyl borate salts of quaternary amine compounds are desirable from the viewpoint of storage stability of the resin composition and insulation properties of the cured product.
Further, from the viewpoint of the appearance of hardening of the thin film portion by the addition of a small amount, tetraphenyl borate salts of imidazole compounds are desirable. Tetraphenyl borate salts can be obtained in high yield by reacting sodium tetraphenyl borate with a predetermined amine compound, imidazole compound, and phosphorus compound. This reaction can be carried out in a known manner. For example, if both compounds are mixed in a water solvent, they are formed as insolubles. After filtration, drying yields the desired compound.

The boron trichloride complex according to the present invention is not particularly limited as long as it has an effect of accelerating the reaction between the epoxy resin and the acid anhydride. Examples of such compounds include boron trichloride monoethylamine complex, boron trichloride phenol complex, boron trichloride piperidine complex, boron trichloride dimethyl complex, boron trichloride N, N-dimethyloctylamine complex, boron trichloride N, N-dimethyldodecylamine complex, boron trichloride N, N-diethyldioctylamine complex (trade name: DY9577 (manufactured by Ciba SC Co., Ltd.))
And the like or a mixture thereof. Among these, boron trichloride N, N-dimethyloctylamine complex is desirable from the viewpoint of storage stability of the resin composition and insulation properties of the cured product.

The amount of the tetraphenylborate salt and / or boron trichloride complex is not particularly limited.
0.005 to 1% by weight of the whole resin composition is desirable. More preferably, the content is 0.01 to 0.15% by weight. 0.00
If it is less than 5% by weight, a sufficient cured product cannot be obtained. On the other hand, if it exceeds 1% by weight, the storage stability of the thermosetting resin composition deteriorates and the pot life becomes short.

The metal salt of an organic acid according to the present invention is not particularly limited as long as it has an effect of accelerating the reaction between an epoxy resin and an acid anhydride. Examples of such compounds include zinc 2-ethylhexanoate, cobalt 2-ethylhexanoate, lead 2-ethylhexanoate, manganese 2-ethylhexanoate, tin naphthenate, lead naphthenate, manganese naphthenate, and zinc naphthenate. , Zinc laurin, zinc palmitate, zinc stearate, zinc acetylacetate, tin acetylacetate, cobalt acetylacetate or manganese acetylacetonate, and the like, or a mixture thereof. Among these, metal carboxylate is desirable from the viewpoint of storage stability of the resin composition and solubility in the resin composition.

The amount of the metal salt of the organic acid (E) is not particularly limited, but may be 0.005 to 1% by weight of the whole resin composition.
Is desirable. More preferably, the content is 0.01 to 0.05% by weight. The compounding ratio of (D) a complex of tetraphenylborate and / or boron trichloride with an amine and (E) a metal salt of an organic acid is as follows: (D) :( E) = 0.005 to 1.0:
0.005 to 1.0% by weight, preferably (D):
(E) = 0.01-0.1: 0.01-0.05% by weight
It is. If the amount is less than 0.005% by weight, a sufficient cured product cannot be obtained. On the other hand, if it exceeds 1% by weight, the storage stability of the thermosetting resin composition deteriorates and the pot life becomes short.

As a method for preparing the thermosetting resin composition according to the present invention, a predetermined amount of an epoxy resin and an acid anhydride are blended and mixed in a stirring vessel, and then a predetermined amount of a tetraphenylborate salt and / or trichloride is mixed. It can be obtained by blending a boron complex and a metal salt of an organic acid and uniformly mixing them. Since the organic acid metal salt has poor solubility, a predetermined amount of the epoxy resin and the organic acid metal salt are mixed in advance in a container capable of being heated and stirred.
After heating and mixing at 120 ° C. for 30 to 60 minutes to completely dissolve the organic acid metal salt, the mixture is cooled to room temperature, and then a predetermined amount of an acid anhydride and a tetraphenylborate salt and / or a boron trichloride complex are blended. By mixing, a thermosetting resin composition can be obtained. In the preparation of the thermosetting resin composition according to the present invention, it is desirable to prepare the composition under a stream of dry air or nitrogen gas or under reduced pressure to suppress moisture absorption of the composition.

The insulating tape relating to the insulating coil of the present invention is obtained by reinforcing the insulating material with a binder resin.
The insulating tape is produced by dissolving a binder resin in a solvent, applying the solution to an insulating material and a reinforcing material, and evaporating the solvent. The insulating material of the insulating tape is a mica foil consisting of flakes obtained by stripping mica raw ore, and the remaining mica raw ore or mica foil, etc., processed by firing, water jet, etc. into fine scales. And a laminated mica foil formed into a sheet by making it into a sheet. The reinforcing material of the insulating tape is not particularly limited as long as it can reinforce the mica foil. For example, an insulating backing material such as a glass cloth, a polyester film, a polyimide film, or a polyester nonwoven fabric is used.

The insulated coil of the present invention can be obtained by insulation treatment by a simple impregnation method. In this simple impregnation method, the coil is impregnated with a resin alone, heat-cured by a heat press, and then incorporated into a stator core slot and connected. That is, the insulating tape is wound on a coil conductor formed in a predetermined shape by combining the insulating tape with an element wire provided with an insulating coating, and this is dried in a vacuum in an impregnation tank to remove volatile components such as moisture in the insulating layer. After removing air and the like, an impregnated resin made of a thermosetting resin is injected, further pressurized and penetrates the wound layer, and is taken out and cured to form an insulating layer. It is also possible to form a surface corona prevention layer for preventing corona discharge between the stator core and the insulation layer of the insulation coil outside the insulation layer. Further, in order to alleviate the shear stress caused by the difference in the coefficient of thermal expansion between the insulating coil and the stator core, it is possible to form a stress relieving layer releasable from the stator core outside the insulating layer.

On the other hand, another insulated coil of the present invention can be obtained by performing insulation treatment by a total impregnation method. In the total impregnation method, a coil before resin impregnation is assembled into a stator core slot, connected, and then impregnated collectively. That is, this insulating coil is provided with an insulating layer in which the above-mentioned insulating tape is wound around a coil conductor, is housed in a stator core slot, is impregnated with the thermosetting impregnating resin together with the stator core, and is hardened. It is obtained by being integrated with the above-mentioned stator core by a cured product.

In the present invention, by blending a tetraphenylborate salt and / or a boron trichloride complex and a metal salt of an organic acid as a curing accelerator, good curability in a thin film portion and a water content of 800 ppm in the composition can be obtained. By doing so, a thermosetting resin composition having excellent storage stability can be obtained.

A thermosetting resin composition containing a tetraphenyl borate salt and / or a boron trichloride complex and a metal salt of an organic acid as a curing accelerator has excellent curability in a thin film portion and storage stability. By using the impregnated resin made of this thermosetting composition, an insulating coil having high reliability, low cost, and good manufacturing workability can be obtained.

[0045]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments. The present invention is not limited to these examples. Incidentally, epoxy resin, acid anhydride, used in Examples and Comparative Examples,
Abbreviations of curing accelerators are as follows.

1) Tetraphenylborate salt BTEA-TPB: benzyltriethylammonium tetraphenylborate TEA-TPB: tetraethylammonium tetraphenylborate 2E4MZ-TPB: 2-ethyl-4-methylimidazolium tetraphenylborate DBU-TPB: 1, 8-diazabicyclo (5,4,
0) Undecenium tetraphenylborate [trade name:
U-CAT5002: manufactured by San Apro Co., Ltd.] 2) Boron trichloride complex DY9577: Boron trichloride N, N-dimethyloctylamine complex [trade name: DY9577: manufactured by Vantico Co., Ltd.] 3) Organic acid metal salt ZnOct : Zinc 2-ethylhexanoate [trade name: zinc octylate, manufactured by Nippon Chemical Industry Co., Ltd.] ZnNp: zinc naphthenate [trade name: zinc naphthenate,
Nippon Chemical Industry Co., Ltd.]

4) Other curing accelerators DBU: 1,8-diazabicyclo (5,4,0) undecene-7 [trade name: DBU: manufactured by San Apro Co.] BTEA-Cl: benzyltriethylammonium chloride [ TEA-Cl: Tetraethylammonium chloride [Tokyo Kasei Co., Ltd.] 2E4MZ: 2-Ethyl-4-methylimidazole [Trade name: 2E4MZ, Shikoku Kasei Kogyo] 5) Epoxy resin E825: bisphenol A type epoxy resin (epoxy equivalent 178) [trade name: E825, manufactured by Yuka Shell Epoxy Co., Ltd.] YX4000: tetramethylbiphenol type epoxy resin (epoxy equivalent 173 [tradename: YX4000, oily shell Epoxy Co., Ltd.] MY790: Bisphenol A type epoxy Resin (epoxy equivalent: 175) [trade name: Araldite MY-790-
E1750: Bisphenol F type epoxy resin (epoxy equivalent 165) [trade name: E1750, manufactured by Yuka Shell Epoxy Co., Ltd.] E834: Bisphenol A type epoxy resin (epoxy equivalent 250) [product] Name: E834, manufactured by Yuka Shell Epoxy Co., Ltd.] E1001: Bisphenol A type epoxy resin (epoxy equivalent: 475) [Product name: E1001, manufactured by Yuka Shell Epoxy Co., Ltd.] 6) Acid anhydride QH-200 : Methyl tetrahydrophthalic anhydride (acid anhydride equivalent: 166) [trade name: QH-200, manufactured by Zeon Corporation]

Synthesis Example 1 (benzyltriethylammonium tetraphenylborate) Benzyltriethylammonium chloride (22.7)
8 g, 0.1 mol) and sodium tetraphenylboride (34.22 g, 0.1 mol) were dissolved in 250 g of ion-exchanged water. An aqueous solution of sodium tetraphenylboron was slowly added dropwise to the aqueous solution of tetraethylammonium chloride, and the mixture was reacted with stirring. After the reaction solution was refluxed at 80 ° C. for 30 minutes, the obtained white precipitate was separated by filtration. The precipitate is N, N-
Recrystallization from dimethyl sulfoxide gave the desired compound.

Synthesis Example 2 (tetraethylammonium tetraphenylborate) Tetraethylammonium chloride (16.57 g,
0.1 mol) and sodium tetraphenylboride (34.22 g, 0.1 mol) were dissolved in 250 g of ion-exchanged water. An aqueous solution of sodium tetraphenylboron was slowly added dropwise to the aqueous solution of tetraethylammonium chloride, and the mixture was reacted with stirring. After the reaction solution was refluxed at 80 ° C. for 30 minutes, the obtained white precipitate was separated by filtration. The precipitate is N, N-
Recrystallization from dimethyl sulfoxide gave the desired compound.

Synthesis Example 3 (2-ethyl-4-methylimidazolium tetraphenylborate) 2-ethyl-4-methylimidazole (11.02 g,
0.1 mol) and sodium tetraphenylboride (34.22 g, 0.1 mol) were dissolved in 250 g of ion-exchanged water, respectively. An aqueous solution of sodium tetraphenylboron was slowly added dropwise to an aqueous solution of 2-ethyl-4-methylimidazole, and the mixture was reacted with stirring.
After the reaction solution was refluxed at 80 ° C. for 30 minutes, the resulting milky white precipitate was filtered off. The precipitate was recrystallized from distilled and purified acetone to obtain the target compound.

Embodiment 1 (1) Preparation of thermosetting resin composition 54.4 parts of epoxy resin (trade name: E825), 45.6 parts of acid anhydride curing agent (trade name: QH-200), boron trichloride amine complex curing accelerator (DY9577) 0.05
Parts were blended to obtain a thermosetting resin composition for impregnation. (2) Evaluation of curability of thin film portion About 1 g of the thermosetting resin composition of the above (1) was weighed on an aluminum Petri dish to form a resin layer having a thickness of about 300 μm, and 0.36 ° C./minute from room temperature. The temperature was raised to 155 ° C. under the temperature raising conditions described above, the temperature was maintained at 155 ° C. for 16 hours, and the thermosetting resin was cured and evaluated. The curability was evaluated at room temperature based on the presence or absence of tackiness on the surface of the cured product, and the results are shown in Table 1. In Table 1, ○ indicates that there is no tack, and × indicates that there is tack.
, Respectively.

(3) Evaluation of water content in the composition The water content of the thermosetting resin composition of the above (1) was measured by the Karl Fischer method. That is, an accurately weighed thermosetting resin composition was injected into a titration flask, and titration was performed with a Karl Fischer reagent until the inside of the flask became anhydrous. Then, based on the following equation, the amount of water contained in the composition was calculated from the titer of the Karl Fischer reagent. Table 1 shows the results.

[0053]

(Equation 1)

(4) Storage stability test The storage stability test of the thermosetting resin composition of the above (1)
The test was performed for about 3 months in a constant temperature bath at a temperature of 40 ° C., and the change with time of the viscosity was measured using an E-type viscometer [manufactured by Toki Sangyo Co., Ltd.]. The judgment was made as the number of days when the viscosity of the thermosetting resin composition reached twice the initial value. The results are shown in Table 1. FIG. 1 shows the viscosity stability with time.

(5) Preparation of Resin Plate The resin plate was prepared by setting a 1.0 mm spacer on a glass plate to which a Teflon (registered trademark) tape was attached and released, and the thermosetting resin of the above (1) was poured. Type, from room temperature to 0.
The temperature was raised to 155 ° C under the temperature increasing condition of 36 ° C,
By holding for 6 hours, the thermosetting resin was cured to obtain a resin plate for evaluation.

(6) Measurement of dielectric loss tangent and volume resistance of resin plate The temperature dependence of the dielectric loss tangent (tan δ) and volume resistance was determined by the method described in (4) above.
The measurement was performed according to JIS C2103 using a resin plate of m as an evaluation sample. The results are shown in Table 1.

Embodiment 2 FIG. A thermosetting resin composition and a resin plate were prepared and evaluated in the same manner as in Example 1 except that 0.094 parts of DY9577 was added. The results are shown in Table 1.

Embodiments 3-6. DY9 blended in Example 1
DBU-TPB (Example 3), BTEA-T as a tetraphenyl borate salt-based curing accelerator instead of 577
PB (Example 4), TEA-TPB (Example 5), 2E
Example 1 except that 4MZ-TPB (Example 6) was blended.
In the same manner as in the above, a thermosetting resin composition and a resin plate were prepared and evaluated. The results are shown in Table 1.

Embodiment 7 FIG. Same as Example 1 except that DBU-TPB was used as a tetraphenylborate salt-based hardening accelerator, and / or DY9577 was used as a boron trichloride complex-based hardening accelerator, and ZnOct was blended as an organic acid metal salt-based hardening accelerator. Then, a thermosetting resin composition and a resin plate were prepared and evaluated. The results are shown in Table 1.

Embodiment 8 FIG. MY as a thermosetting resin composition
790: 23.5 parts, E1750: 23.5 parts, YX4
000: 5 parts and QH200: 48.0 parts,
Tetraphenylborate salt curing accelerator DBU-TPB
And / or boron trichloride complex-based accelerator DY957
7, and ZnOct as an organic acid metal salt-based curing accelerator
A thermosetting resin composition and a resin plate were prepared and evaluated in the same manner as in Example 1 except that was added. The results are shown in Table 1.

Embodiment 9 FIG. MY as a thermosetting resin composition
790: 23.5 parts, E1750: 23.5 parts, YX4
000: 5 parts and QH200: 48.0 parts,
A thermosetting resin composition and a resin plate were prepared and evaluated in the same manner as in Example 1 except that ZnOct was blended as an organic acid metal salt-based curing accelerator. The results are shown in Table 1.

Comparative Example 1 A thermosetting resin composition and a resin plate were prepared and evaluated in the same manner as in Example 1 except that 2000 ppm of water was added. The results are shown in Table 1. FIG. 1 shows the viscosity stability with time. As is clear from Table 1 and FIG. 1, when the amount of water contained in the thermosetting resin composition exceeds 800 ppm, the viscosity of the thermosetting resin composition increases rapidly, and storage stability is impaired. Also,
As compared with Example 1, the characteristics of the resin plate are deteriorated.

Comparative Examples 2 to 9 800 ppm to 20 moisture
Except for adding 00 ppm, in the same manner as in Examples 2 to 9,
A thermosetting resin composition and a resin plate were prepared and evaluated.
The results are shown in Table 1. As is clear from Table 1, storage stability is impaired.

Example 10 (1) Preparation of Binder Solution for Insulating Tape As a binder resin solution for producing an insulating tape according to the present invention, 50 parts of an epoxy resin (trade name: E1001) was used.
Parts, a composition comprising 50 parts of an epoxy resin (trade name: E834) and 7 parts of a curing accelerator (zinc octylate), dissolved in a 1: 1 mixed organic solvent of acetone and toluene, and Was prepared so as to have a concentration of about 25% by weight.

(2) Preparation of Insulating Tape Using the binder resin solution for an insulating tape obtained in the above (1), the thickness of a laminated mica sheet [trade name: DR-2, manufactured by Okabe Mica Industry Co., Ltd.] 0.07mm, width 1000m
m and a glass cloth having a thickness of 0.03 mm are bonded together, and the mixed organic solvent of the binder resin solution is heated and dried at 140 ° C. for 5 minutes, and the binder resin content is 6 to 10% by weight.
Was produced.

(3) Manufacture of Insulated Coil by Total Impregnation Method FIG. 2 is an explanatory view for explaining an insulated coil according to an embodiment of the present invention. Show. In the figure, 1 is a stator core laminated with silicon steel plates, 2 is an insulating coil of the embodiment of the present invention, 3 is a conductor, 4 is an insulating layer, 5 is a wedge, 6 is an intermediate filler, 7
Is a stator core slot, and 8 is a protective insulating layer. The insulating coil 2 is formed by winding the insulating tape obtained in the above (1) a predetermined number of times around the conductor 3 to form an insulating layer 4 of the coil. A glass tape is wound around the surface of the insulating layer 4 for protective insulation. Layer 8. This is inserted into the core slot 7 and the wedge 5
And the coil 2 was fixed. Thereafter, after impregnating the thermosetting resin prepared in Example 1 at 40 ° C., the temperature was raised from room temperature to 155 ° C. at a rate of 0.36 ° C./min.
For 16 hours to cure the thermosetting resin to obtain an insulating coil.

(4) Production of Insulated Coil by Single Impregnation Method An insulating tape is wound around the coil conductor a predetermined number of times to form a ground insulating layer, and a glass tape is further wound as a protective insulating layer. After the thermosetting resin prepared in 1 was impregnated at 40 ° C., it was inserted into a mold, and the mold temperature was set to 155.
° C., to obtain an insulating coil is heated and pressurized and held at a pressure of 20 kg / cm ² 16 hours to cure the thermosetting resin.

(5) Measurement of Insulation Characteristics of Insulation Coil The insulation characteristics of the insulation coil were as follows: dielectric loss tangent-voltage characteristics (Δtan
δ) (difference in dielectric loss tangent between 12 kV and 2 kV) and breakdown voltage (BDV) (measured in oil at a constant boost of 1 kV / sec). Table 2 shows the results. (6) Evaluation of Curability of Insulated Coil Thin Film Resin Part The insulated coil thin film resin part of (3) and (4) was evaluated. The curability was evaluated at room temperature based on the presence or absence of tackiness, and the results are shown in Table 2. In Table 2, the case where there is no tack is represented by ○, and the case where there is tack is represented by ×.

Examples 11 to 18 Insulating coils were prepared in the same manner as in Example 1 except that the thermosetting resin compositions for impregnation prepared in Examples 2 to 9 were used. Was evaluated. The results are shown in Table 2.

Comparative Examples 10 to 15 Insulating coils were produced in the same manner as in Example 10 except that the thermosetting resin compositions for impregnation were used, and the thermosetting resin compositions for impregnation prepared in Comparative Examples 1 to 6 were used. Was evaluated. The results are shown in Table 2.

As is apparent from Table 2, since the organic acid metal salt-based curing accelerator was not blended and only the tetraphenyl borate salt-based curing accelerator was blended, the insulating coil was compared with Examples 10 to 15. The curability of the thin film resin part is reduced.

COMPARATIVE EXAMPLES 16 AND 17 The thermosetting resin compositions for impregnation prepared in Comparative Examples 7 and 8 were the same as those of the impregnating thermosetting resin compositions except that the catalyst used was not a tetraphenylborate salt. Using things,
Otherwise, an insulated coil was manufactured and evaluated in the same manner as in Example 10. The results are shown in Table 2. As is apparent from Table 2, the viscosity of the thermosetting resin composition increases during storage and impregnation of the resin because the curing accelerator not formed as a tetraphenylborate salt is blended, and the resin is reduced to details. Since it was not impregnated, the insulation characteristics of the insulation coil were lower than those of Examples 16 and 17. Further, since the storage stability is as short as two days, frequent resin replacement is required, and the cost of the insulating coil increases.

Comparative Example 18 An insulating coil was prepared and evaluated in the same manner as in Example 10 except that the thermosetting resin composition for impregnation used was the thermosetting resin composition for impregnation prepared in Comparative Example 9. went. The results are shown in Table 2. As is clear from Table 2, the curability of the resin portion of the insulating coil thin film is reduced because only the organic acid metal salt-based curing accelerator is blended without using the tetraphenyl borate salt-based curing accelerator. .

[0074]

[Table 1]

[0075]

[Table 2]

[0076]

The first thermosetting resin composition according to the present invention comprises (A) an epoxy resin having two or more epoxy groups in a molecule, (B) a liquid polycarboxylic anhydride, and (C) )
An epoxy resin composition containing a curing catalyst, wherein the water content in the composition at the initial stage of blending is 800 ppm or less, and has an effect of providing excellent curability and storage stability in a thin film portion.

In the second thermosetting resin composition according to the present invention, since the curing catalyst is (D) a complex of tetraphenylborate and / or boron trichloride with an amine, good curability in a thin film portion is obtained. And the storage stability can be easily achieved, and a favorable effect of accelerating the reaction between the epoxy resin and the acid anhydride can be obtained.

In the third thermosetting resin composition according to the present invention, the curing catalyst may comprise (D) a complex of tetraphenylborate and / or boron trichloride and an amine, and (E)
Since it is an organic acid metal salt, it is possible to easily achieve good curability and storage stability in a thin film portion, and to obtain a more favorable effect of accelerating the reaction between an epoxy resin and an acid anhydride.

In the first and second thermosetting resin compositions according to the present invention, tetraphenyl borate and / or a complex of boron trichloride and amine may be used in an amount of 0.1% based on the total amount of the resin composition. When the content is from 005 to 1.0% by weight, a sufficient cured product can be obtained, and good storage stability can be obtained.

In the first and third thermosetting resin compositions according to the present invention, tetraphenyl borate and / or a complex of boron trichloride and an amine may be used in an amount of 0.1% based on the total amount of the resin composition. 005 to 1.0% by weight, and the organic acid metal salt is 0.0
When the amount is from 0.05 to 1.0% by weight, a more sufficient cured product can be obtained, and more favorable storage stability can be obtained.

The fourth thermosetting resin composition according to the present invention is characterized in that, in the above-mentioned first, second or third thermosetting resin composition, the tertiary borate and the amine salt, wherein the amine is a quaternary amine compound or Imidazole compound or 1,
Since it is 8-diazabicyclo (5,4,0) undecene-7, a resin composition having excellent storage stability and excellent insulation properties of a cured product can be obtained.

In the fifth thermosetting resin composition according to the present invention, since the amine is N, N-dimethyloctylamine in the complex of boron trichloride and amine, the storage stability and cured product of the resin composition Can be obtained with particularly good insulation properties.

The first insulated coil according to the present invention was cured by winding a coil conductor and an insulating tape formed by bonding an insulating material to a reinforcing material with a binder resin, impregnating with a thermosetting resin, and curing the coil conductor. In an insulating coil provided with an insulating layer, since the thermosetting resin is made of the thermosetting resin composition, it is most suitable for a simple impregnation type insulating system, and a dense insulating layer can be formed. This is advantageous in that it has high efficiency, is low in cost, and has good workability.

In the second insulating coil according to the present invention, the coil conductor is provided with an insulating layer formed by winding an insulating tape obtained by bonding an insulating material to a reinforcing material with a binder resin, and is accommodated in a stator core slot. A thermosetting resin is impregnated and cured together with a stator core, and in an insulating coil integrated with the stator core by a cured product of the thermosetting resin, the thermosetting resin includes the thermosetting resin. Since it is composed of the composition, the process can be simplified by impregnating the coil and shortening the thermosetting time, which has the effects of high reliability, low cost and good workability.

[Brief description of the drawings]

FIG. 1 is a graph for explaining the viscosity stability of a resin composition according to an example of the present invention.

FIG. 2 is an explanatory diagram illustrating an insulated coil according to an embodiment of the present invention.

[Explanation of symbols]

1 stator core, 2 insulating coils, 3 conductors, 4 insulating layers, 5 wedges, 6 intermediate fillers, 7 stator core slots, 8 protective layers.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takamitsu Fujimoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Mitsubishi Electric Corporation (reference) 4J036 AC02 AC05 AD07 AD08 AD09 AE07 AF06 AF08 AG00 AJ08 DB17 DB21 DC19 GA06 GA11 JA05 5G305 AA02 AA12 AB02 AB24 AB36 BA09 CA06 CA15 CB16 CB24 CB27 CD08

Claims (9)

[Claims] 1. An epoxy resin composition comprising (A) an epoxy resin having two or more epoxy groups in a molecule, (B) a liquid polycarboxylic anhydride, and (C) a curing catalyst. The amount of water contained in the composition at the initial stage of blending is 80
A thermosetting resin composition having a content of 0 ppm or less. 2. The thermosetting resin composition according to claim 1, wherein the curing catalyst is (D) a complex of tetraphenyl borate and / or boron trichloride with an amine. 3. The thermosetting resin composition according to claim 1, wherein the curing catalyst is (D) a complex of amine with tetraphenyl borate and / or boron trichloride, and (E) a metal salt of an organic acid. 4. The compounding amount of the curing catalyst is such that the complex of the amine with tetraphenyl borate and / or boron trichloride is 0.005 to 1.0% by weight of the whole resin composition. 3. The thermosetting resin composition according to 1 or 2. 5. The amount of the curing catalyst is as follows: tetraphenyl borate and / or a complex of boron trichloride and an amine is 0.005 to 1.0% by weight of the whole resin composition; 0.0
The thermosetting resin composition according to claim 1 or 3, wherein the amount is from 0.5 to 1.0% by weight. 6. The tetraphenylborate and amine salt, wherein the amine is a quaternary amine compound, an imidazole compound, or 1,8-diazabicyclo (5,4,0) undecene-7. 3,
The thermosetting resin composition according to claim 4 or claim 5. 7. A complex of boron trichloride and an amine,
6. The thermosetting resin composition according to claim 1, wherein the amine is N, N-dimethyloctylamine. 8. An insulating coil comprising: a coil conductor; and an insulating layer formed by winding an insulating tape formed by bonding an insulating material to a reinforcing material with a binder resin, winding the insulating tape around the conductor, impregnating the thermosetting resin, and curing the insulating tape. , Wherein the thermosetting resin is
An insulated coil, which is the thermosetting resin composition according to claim 3, 4, 5, 6, or 7. 9. An insulating layer in which an insulating tape formed by bonding an insulating material to a reinforcing material with a binder resin is wound around a coil conductor, housed in a stator core slot, and made of a thermosetting resin together with the stator core. An insulating coil which is impregnated and cured, and is integrated with the stator core by a cured product of the thermosetting resin, wherein the thermosetting resin comprises:
An insulating coil comprising the thermosetting resin composition according to claim 5, 6 or 7.