JP4969816B2 - RESIN COMPOSITION, PROCESS FOR PRODUCING THE SAME AND ELECTRIC DEVICE USING THE SAME - Google Patents

Description

  The present invention relates to an electric apparatus having a casting member or a structural member that performs electrical insulation, and particularly to a resin composition that achieves both a high dielectric constant and a low thermal expansion coefficient.

  Switchgears that house vacuum valves, gas-insulated switchgears that contain sulfur hexafluoride gas, and in-pipe power transmission devices are used as switchgears and power transmission devices for high-voltage circuits used in substations, etc. Yes. In these power transmission and transformation equipment, casting members for insulating vacuum valves and high-voltage conductors and structural members for insulating and supporting high-voltage conductors in metal containers are used. In response to demands for reducing the electric field, attempts have been made to reduce the electric field at the interface between the high-voltage conductor and the insulator by changing the dielectric constant of these casting and structural members.

  For example, in the switchgear described in Patent Literature 1, the dielectric constant of the insulator covering the insulating barrier attached to the fixed side and the movable side of the vacuum valve is set to a different dielectric constant from that of other parts, so that The electric field is reduced to improve the dielectric strength between ground and between phases. In addition, in the insulating spacer described in Patent Document 2, an insulating material having a different dielectric constant is used between the high-voltage conductor portion and the grounding vessel between the high-voltage conductor portion and the grounding vessel. We are trying to reduce stress.

  As the material of the casting / structural member as described above, it is common to use a casting made of an epoxy resin having excellent properties such as mechanical strength, heat resistance, and electrical insulation. In order to supplement mechanical and thermal properties that are insufficient with epoxy resin alone, or to provide new functions, inorganic particles, glass fibers, and the like are used as a reinforcing material. For example, Patent Document 3 attempts to improve mechanical strength and suppress thermal expansion by highly filling silica particles and core-shell type rubber particles. Moreover, in patent document 4, the high dielectric constant of the resin mixture is aimed at by filling an epoxy resin with particles having a high dielectric constant such as titanium oxide or barium titanate.

JP 2001-110287 A JP-A-5-260619 JP2002-15621 JP 2004-285105 A

  However, the above-described conventional techniques have the following problems. That is, it is theoretically possible to reduce the electrical stress at the boundary between the high voltage conductor and the insulating spacer by changing the dielectric constant of the insulating casting as described in Patent Document 1 and Patent Document 2. However, these documents do not describe a specific method for changing the dielectric constant or a specific method for manufacturing an insulating casting having a changed dielectric constant. Moreover, it is very difficult to produce the insulating barrier mold or insulating spacer described in Patent Document 1 and Patent Document 2 using the insulating castings described in Patent Document 3 and Patent Document 4.

  In the insulating casting described in Patent Document 3, the fracture toughness is improved and the coefficient of thermal expansion is suppressed by highly filling silica particles and core-shell rubber particles. Since the rate is about 2 to 3 times that of the epoxy resin, the dielectric constant cannot be changed greatly. Moreover, in the insulating composition described in Patent Document 4, it is possible to change the dielectric constant by filling titanium oxide particles having a dielectric constant as high as about 100 times that of an epoxy resin. Since the diameter is generally smaller than that of the silica particles, when the titanium oxide particles are highly filled, the resin viscosity increases and workability is remarkably lowered. For this reason, it is difficult to suppress the coefficient of thermal expansion due to high filling with titanium oxide particles.

  The present invention has been proposed in order to solve the problems of the prior art as described above, and its purpose is to appropriately select a material to be filled in the epoxy resin, thereby to achieve a high dielectric constant and a low coefficient of thermal expansion. In addition to providing a resin composition capable of providing an insulating material having excellent mechanical strength and a method for producing the same, the use of such an insulating material enables a small, high-performance and highly reliable electrical device. Is to provide.

In order to solve the above-described problems, the present invention provides an oxide-based particle comprising a layered silicate compound and silica in an epoxy resin comprising an epoxy compound having two or more epoxy groups per molecule and a curing agent for epoxy resin. In the resin composition in which high dielectric constant particles made of titanium oxide are dispersed, 10 to 60 parts by weight of the layered silicate compound and 200 to 250 of the oxide-based particles are used with respect to 100 parts by weight of the epoxy compound. Part by weight and the high dielectric constant particles are filled at a ratio of 200 to 250 parts by weight, respectively, and the total filling amount of the oxide-based particles and the high dielectric constant particles is 500 parts by weight or less.

  That is, by filling both oxide-based particles and high dielectric constant particles, it is possible to impart the necessary dielectric constant to the epoxy resin while suppressing thermal expansion, and to suppress an increase in the viscosity of the epoxy resin. There is no decline. Furthermore, the layered silicate compound is dispersed in the epoxy resin at the nanoscale, thereby restraining the polymer chain of the epoxy resin and suppressing the movement of the molecular chain due to heat, thereby suppressing thermal expansion and generating cracks. In such a case, since the progress can be suppressed, the fracture toughness can be improved.

  In addition, by using an insulating material that has both a high dielectric constant and a low thermal expansion coefficient and excellent mechanical strength as an insulator for casting members and structural members of electrical equipment, The electrical stress at the boundary can be reduced, and the thermal expansion coefficient of the insulator can be made the same as that of the high-voltage conductor, so that the interface between the high-voltage conductor and the insulator due to heat generation during operation can be prevented and destroyed. Mechanical strength such as toughness can be secured. Therefore, it is possible to provide a small, high-performance and highly reliable electric apparatus.

  As described above, according to the present invention, an insulating material having both a high dielectric constant and a low coefficient of thermal expansion and excellent mechanical strength can be provided by appropriately selecting a material to be filled in an epoxy resin. A resin composition and a manufacturing method thereof can be provided, and by using such an insulating material, a small, high-performance and highly reliable electric apparatus can be provided.

  Hereinafter, embodiments for carrying out the present invention as described above will be described with reference to the drawings.

[Configuration of Resin Composition]
FIG. 1 is a schematic view showing one embodiment of a resin composition according to the present invention. As shown in FIG. 1, a resin composition 1 includes a layered silicate compound 3 and an oxide-based particle in an epoxy resin 2 composed of an epoxy compound having two or more epoxy groups per molecule and a curing agent for epoxy resin. 4 and high dielectric constant particles 5 are constituted by uniformly dispersing three kinds of inorganic particles. Below, each component 2-5 is demonstrated in detail.

[Epoxy compound]
The epoxy compound having two or more epoxy groups per molecule used for the epoxy resin 2 can be cured with two or more three-membered rings composed of two carbon atoms and one oxygen atom in one molecule. Any compound can be used as appropriate, and the type of the compound is not limited. Specific epoxy compounds include, for example, bisphenol A type epoxy resins, brominated bisphenol A type epoxy resins, hydrogenated bisphenol A types obtained by condensation of epichlorohydrin with polyhydric phenols such as bisphenols and polyhydric alcohols. Epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, novolac type epoxy resin, phenol novolac type epoxy resin, orthocresol novolak Type epoxy resins, tris (hydroxyphenyl) methane type epoxy resins, tetraphenylolethane type epoxy resins and other glycidyl ether type epoxy resins, and epichlor Dorin and glycidyl Jijiru ester epoxy resins obtained by condensation of Garubon acid, and heterocyclic epoxy resins such as hydantoin epoxy resin obtained by the reaction of triglycidyl isocyanate or epichlorohydrin with Hidaiton acids and the like. These epoxy compounds can be used alone or as a mixture of two or more.

[Curing agent for epoxy resin]
The curing agent for epoxy resin used for the epoxy resin 2 can be appropriately used as long as it can chemically react with the above-described epoxy compound to cure the epoxy compound, and the kind thereof is not limited. Specific epoxy resin curing agents include, for example, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, hexamethylenediamine, dipropylenediamine, polyether diamine, 2,5-dimethylhexamethylenediamine, Trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis (hexamethyl) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aminoethylethanolamine, tri (methylamino) hexane, dimethylaminopropylamine, diethylamino Propylamine, methyliminobispropylamine, mensendiamine, isophoronediamine, bis (4-amino-3-methyldicyclohexyl) methane, diaminodi Chlohexylmethane, bis (aminomethyl) cyclohexane, N-aminoethylpiperazine, 3,9-bis (3-aminopropyl) 2,4,8,10-tetraoxaspiro (5,5) undecane, m- Amine-based curing agents such as xylenediamine, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiethyldiphenylmethane, dicyandiamide, organic acid dihydrazide, dodecenyl succinic anhydride, polyadipic acid anhydride, polyazeline acid anhydride, polysebacic acid anhydride , Poly (ethyloctadecanedioic acid) anhydride, poly (phenylhexadecanedioic acid) anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydro Water phthalic acid, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid, ethylene glycol bistrimellitate, glycerol tris trimellitate, Acid anhydride hardeners such as het anhydride, tetrabromophthalic anhydride, nadic anhydride, methyl nadic anhydride, polyazeline anhydride, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-heptadecylimidazole, etc. Imidazole-based curing agents, polymercaptan-based curing agents such as polysulfide and thioester, phenol-based curing agents, Lewis acid-based curing agents, and isocyanate-based curing agents. These epoxy resin curing agents can be used alone or as a mixture of two or more.

[Curing accelerator for epoxy resin]
In the epoxy resin 2, an epoxy resin curing accelerator capable of accelerating or controlling the curing reaction of the epoxy resin can be used in combination with the epoxy resin curing agent described above. In particular, when an acid anhydride curing agent is used as a curing agent for an epoxy resin, the curing reaction is slow compared to other curing agents such as an amine curing agent, so use an epoxy resin curing accelerator. Is desirable. Suitable curing accelerators for acid anhydride curing agents include, for example, tertiary amines or salts thereof, quaternary ammonium compounds, imidazoles, alkali metal alkoxides, and the like.

[Layered silicate compound]
The layered silicate compound 3 may be at least one selected from a mineral group consisting of a smectite group, a mica group, a vermiculite group, and a mica group. Here, examples of the layered silicate compound belonging to the smectite group include montmorillonite, hectorite, saponite, sauconite, beidellite, stevensite, nontronite and the like. Examples of the layered silicate compound belonging to the mica group include chlorite, phlogopite, lepidrite, mascobite, biotite, paragonite, margarite, teniolite, tetrasilicic mica and the like. Examples of layered silicate compounds belonging to the vermiculite group include trioctahedral vermiculite and dioctahedral vermiculite, and examples of layered silicate compounds belonging to the mica group include muscovite, biotite, paragonite, levitrite, margalite. Light, clintnite, anandite, etc. are mentioned. Any layered silicate compound can be selected. From the viewpoint of dispersibility in an epoxy resin, a layered silicate compound belonging to the smectite group is particularly desirable. These layered silicate compounds can be used alone or as a mixture of two or more.

  Further, these layered silicate compounds have a structure in which silicate layers are laminated, and various substances such as ions, molecules, clusters, etc. can be held between the layers by an ion exchange reaction (intercalation). Therefore, various organic compounds can be inserted between the silicate layers. The organic compound inserted between the layers of the layered silicate compound can be used as long as it is an organic compound that can impart affinity to the epoxy resin to the layered silicate compound, and the type thereof is not limited, but ion exchange treatment Considering the degree of intercalation between the quaternary ammonium ions, it is desirable.

  Examples of the quaternary ammonium ion include tetrabutylammonium ion, tetrahexylammonium ion, dihexyldimethylammonium ion, dioctyldimethylammonium ion, hexatrimethylammonium ion, octatrimethylammonium ion, dodecyltrimethylammonium ion, hexadecyltrimethylammonium ion. , Stearyltrimethylammonium ion, dococenyltrimethylammonium ion, cetyltrimethylammonium ion, cetyltriethylammonium ion, hexadecylammonium ion, tetradecyldimethylbenzylammonium ion, stearyldimethylbenzylammonium ion, dioleyldimethylammonium ion, N-methyldi Tanol lauryl ammonium ion, dipropanol monomethyl lauryl ammonium ion, dimethyl monoethanol lauryl ammonium ion, polyoxyethylene dodecyl monomethyl ammonium ion, dimethyl hexadecyl octadecyl ammonium ion, trioctyl methyl ammonium ion, tetramethyl ammonium ion, tetrapropyl ammonium ion, etc. Is mentioned. These quaternary ammonium ions can be used alone or as a mixture of two or more.

Examples of the oxide-based particles 4 include silica, alumina , bismuth trioxide, cerium dioxide, cobalt monoxide, copper oxide, iron trioxide, holmium oxide, indium oxide, manganese oxide, tin oxide, yttrium oxide, and zinc oxide. Is mentioned. These oxide-based particles can be used alone or as a mixture of two or more.

[High dielectric constant particles]
Examples of the high dielectric constant particles 5 include titanium oxide, barium titanate, calcium titanate, strontium titanate, bismuth titanate, barium neodymium titanate, magnesium titanate, barium tin titanate, barium zirconate titanate, and carbon. Examples thereof include black, silicon carbide, titanium-barium-neodymium composite oxide, and lead-calcium composite oxide. These high dielectric constant particles can be used alone or as a mixture of two or more.

[Coupling agent or surface modifier]
Further, for the purpose of improving the adhesion between the epoxy resin and the layered silicate compound by modifying the surface of the layered silicate compound 3, the oxide-based particles 4 and the high dielectric constant particles 5, the dispersed layered silicate compound is used. For the purpose of suppressing the reaggregation of 3 in the epoxy resin 1, a coupling agent or a surface treatment agent can be used. Examples of the coupling agent or surface treatment agent include γ-glycidoxy-propyltrimethoxysilane, γ-aminopropyl-trimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidyloxypropyl- Examples include silane coupling agents such as trimethoxysilane, titanate coupling agents, and aluminum coupling agents. These coupling agents or surface treatment agents can be used alone or as a mixture of two or more.

[Combination ratio]
In order to obtain an insulating material having both a high dielectric constant and a low thermal expansion coefficient and excellent mechanical strength, a combination of three types of inorganic particles, that is, a layered silicate compound, an oxide-based particle, and a high dielectric constant particle with respect to an epoxy compound The ratio is desirably set within the range shown in FIG. As shown in FIG. 2, the ratio of 1 to 50 parts by weight of the layered silicate compound, 100 to 400 parts by weight of the oxide-based particles, and 100 to 400 parts by weight of the high dielectric constant particles with respect to 100 parts by weight of the epoxy compound. Respectively. And the sum total of the filling amount of an oxide type particle | grain and a high dielectric constant particle shall be 500 weight part or less with respect to 100 weight part of epoxy compounds. The limitation of the blending ratio of such inorganic particles is due to the following reason.

  The amount of the layered silicate compound is 1 to 50 parts by weight with respect to 100 parts by weight of the epoxy compound, thereby suppressing the thermal expansion of the resin composition and improving the fracture toughness. The increase in viscosity can be suppressed, and the work efficiency of casting and structural member manufacturing can be prevented from being lowered. That is, when the compounding amount of the layered silicate compound is less than 1 part by weight with respect to 100 parts by weight of the epoxy compound, it becomes difficult to suppress the thermal expansion of the resin composition, and it becomes difficult to improve the fracture toughness. . On the contrary, when the compounding amount of the layered silicate compound exceeds 50 parts by weight with respect to 100 parts by weight of the epoxy compound, the viscosity of the resin composition increases, so that the oxide particles and the high dielectric constant particles are uniformly dispersed. Is difficult, and also leads to a decrease in work efficiency of casting and structural member manufacturing.

  The compounding amount of the oxide particles can be 100 to 400 parts by weight with respect to 100 parts by weight of the epoxy compound, thereby suppressing the thermal expansion and viscosity increase of the resin composition. That is, when the compounding amount of the oxide-based particles is less than 100 parts by weight with respect to 100 parts by weight of the epoxy compound, it is difficult to suppress the thermal expansion of the resin composition. Conversely, when the compounding amount of the oxide-based particles exceeds 400 parts by weight with respect to 100 parts by weight of the epoxy compound, the viscosity of the resin composition increases, so that the oxide-based particles and the high dielectric constant particles are uniformly dispersed. It becomes difficult.

  The blending amount of the high dielectric constant particles is 100 to 400 parts by weight with respect to 100 parts by weight of the epoxy compound, thereby giving the resin composition a necessary dielectric constant and suppressing an increase in the viscosity of the resin composition. I can do it. That is, when the blending amount of the high dielectric constant particles is less than 100 parts by weight with respect to 100 parts by weight of the epoxy compound, it is difficult to impart a necessary dielectric constant to the resin composition. On the contrary, when the blending amount of the high dielectric constant particles exceeds 400 parts by weight with respect to 100 parts by weight of the epoxy compound, the viscosity of the resin composition increases, so that the oxide particles and the high dielectric constant particles are uniformly dispersed. It becomes difficult.

  By making the total filling amount of the oxide-based particles and the high dielectric constant particles 500 parts by weight or less with respect to 100 parts by weight of the epoxy compound, an increase in the viscosity of the resin composition can be suppressed. That is, even when the individual blending ratio of the oxide particles and the high dielectric constant particles is within the above range, if the total filling amount exceeds 500 parts by weight with respect to 100 parts by weight of the epoxy compound, the resin composition The increase in the viscosity of the product becomes significant, making it difficult to use as a casting resin.

[Production process of resin composition]
FIG. 3 is a flowchart showing an example of the manufacturing process of the resin composition described above. As shown in FIG. 3, in the production of the resin composition, first, a layered silicate compound is added to an epoxy compound, and mixed and dispersed while applying a shearing force (S01). By applying a shearing force, the layered silicate compound can be uniformly dispersed in the epoxy resin.

  That is, the layered silicate compound is nano-sized particles with a large aspect ratio laminated with a length and width of about 100 nm each and a thickness of several nanometers. There is a need to do. In this case, if a particle having a particle size larger than that of the layered silicate compound, such as an oxide-based particle or a high dielectric constant particle, is present in the epoxy compound, the shearing force from the mixer does not sufficiently reach the layered silicate compound. Therefore, it becomes difficult to uniformly disperse. For this reason, in the particle dispersion step for the epoxy compound, it is necessary to first disperse the layered silicate compound as shown in FIG.

  In addition, as a mixing apparatus for performing shear mixing, any apparatus that can mix while applying a shearing force can be used as appropriate, and the type of the mixing apparatus is not particularly limited. , Three roll mill mixer, homogenizer mixer, lab plast mill mixer (manufactured by Toyo Seiki Seisakusho Co., Ltd.), Miracle KCK (manufactured by Asada Iron Works), Distromix (manufactured by ATEC Japan Co., Ltd.), Clear S55 (M Technic Co., Ltd.).

  During the shear mixing (S01) of the layered silicate compound, it is also desirable to modify the surface of the layered silicate compound with the coupling agent or the surface treatment agent by mixing the coupling agent or the surface treatment agent together. By performing the surface modification of the layered silicate compound in this manner, the interface adhesion between the epoxy resin and the layered silicate compound can be strengthened. Further, the layered silicate compound can be improved in affinity for the epoxy compound by organic modification with a quaternary ammonium ion in advance.

  Subsequently, oxide particles and high dielectric constant particles are added to the epoxy compound in which the layered silicate compound is dispersed, and mixed and dispersed (S02). In this case, if the coupling agent or the surface treatment agent is mixed during the shear mixing (S01) of the layered silicate compound, the surface modification can be performed also on the oxide particles and the high dielectric constant particles. The interfacial adhesion can be strengthened.

  As described above, the epoxy resin curing agent is added to the mixture obtained by dispersing the layered silicate compound in the epoxy compound by shear mixing, and subsequently dispersing the oxide-based particles and the high dielectric constant particles. By mixing (S03), the above resin composition can be obtained. Furthermore, the target insulating material can be produced by heat-curing the resin composition.

[Operations and effects of the embodiment]
As described above, according to the present embodiment, a layered silicate compound, an oxide-based particle, and a high dielectric constant are contained in an epoxy resin composed of an epoxy compound having two or more epoxy groups per molecule and an epoxy resin curing agent. By dispersing the rate particles, an insulating material having both a high dielectric constant and a low coefficient of thermal expansion and excellent mechanical strength can be provided.

  That is, by filling both oxide-based particles and high dielectric constant particles, it is possible to impart the necessary dielectric constant to the epoxy resin while suppressing thermal expansion, and to suppress an increase in the viscosity of the epoxy resin. There is no decline. Furthermore, the layered silicate compound is dispersed in the epoxy resin at the nanoscale, thereby restraining the polymer chain of the epoxy resin and suppressing the movement of the molecular chain due to heat, thereby suppressing thermal expansion and generating cracks. In such a case, since the progress can be suppressed, the fracture toughness can be improved.

  In addition, by using an insulating material that has both a high dielectric constant and a low thermal expansion coefficient and excellent mechanical strength as an insulator for casting members and structural members of electrical equipment, The electrical stress at the boundary can be reduced, and the thermal expansion coefficient of the insulator can be made the same as that of the high-voltage conductor, so that the interface between the high-voltage conductor and the insulator due to heat generation during operation can be prevented and destroyed. Mechanical strength such as toughness can be secured. Therefore, it is possible to provide a small, high-performance and highly reliable electric apparatus.

[Application to electrical equipment]
As a specific application to an electric device, a cast insulator 42 for molding a vacuum valve 41 as shown in FIG. 4 is manufactured from the resin composition of this embodiment, or a high-voltage conductor as shown in FIG. Insulating spacers 52 that insulate and support 51 can be manufactured. Such cast insulator 42 and insulating spacer 52 can reduce the electrical stress at the boundary between the high-voltage conductor and the insulator, and the thermal expansion coefficient of the metal (copper, aluminum, etc.) such as the high-voltage conductor and the insulator is comparable. Therefore, separation of the interface between the high-voltage conductor and the insulator due to heat generated during operation can be prevented, and mechanical strength such as fracture toughness can be secured.

  Therefore, in a switchgear such as a gas insulated switchgear or a pipeline air power transmission device, a small, high-performance and highly reliable switch can be obtained by using the vacuum valve 41 and the insulating spacer 52 as shown in FIGS. Gear can be realized.

  Next, specific examples of the present invention and comparative examples according to the prior art will be shown, and actions and effects of the present invention will be described in more detail by contrasting evaluation of these examples and comparative examples.

[Example 1]
In Example 1, an organically modified layered silicate compound and a surface treatment coupling agent were epoxy-modified by the production process described in the above-described embodiment (FIG. 3) at a desirable blending ratio within the range described in FIG. It was added to the compound and shear mixed, followed by mixing of oxide-based particles and high dielectric constant particles. The details of Example 1 are as follows.

  First, 100 parts by weight of an epoxy compound (bisphenol A type epoxy resin, manufactured by Japan Epoxy Resin Co., Ltd.) and 10 parts by weight of a layered silicate compound that is organically modified with a quaternary ammonium ion (primary particle size of 1 to several hundred nm, Coop Chemical Co., Ltd.) And silane coupling agent: 1 part by weight of γ-glycidoxy-propyltrimethoxysilane (manufactured by Nihon Unicar Co., Ltd., trade name: A187) was added and mixed by applying shearing force.

  To this mixture, 200 parts by weight of silica (Crystallite A1, Tatsumori) as oxide-based particles and 200 parts by weight of titanium oxide (MT-100S, manufactured by Teika) as high-permittivity particles are added. (Dalton Co., Ltd., trade name: 5DMV-r type). To this mixture, 86 parts by weight of an acid anhydride curing agent for epoxy resin (manufactured by Nippon Nippon Chemical Co., Ltd., trade name: Ricacid MH-700) and a curing accelerator for acid anhydride curing agent (manufactured by NOF Corporation, product Name: M2-100) 1 part by weight was added and mixed at 80 ° C. for 10 minutes to prepare a resin composition.

  The resin composition thus adjusted is poured into a mold heated to 100 ° C. in advance, and after vacuum degassing, a curing treatment is performed under conditions of 100 ° C. × 3 hours (primary curing) + 150 ° C. × 15 hours (secondary curing). By applying, the target insulating material was produced. This insulating material was subjected to the characteristic evaluation described later.

  In the other Examples 2 and 3 and Comparative Examples 1 and 2, the product identification (manufacturer and product name) such as the type of material used and the type of device is the same as in Example 1. In the following description, description of individual product identification is omitted.

[Example 2]
As Example 2, the same mixing ratio as in Example 1 was used, but the oxide particles and the high dielectric constant particles were bonded to the epoxy particles without using a surface treatment coupling agent by a production process different from Example 1. After mixing with the compound, the non-organically modified layered silicate compound was mixed without applying shear. The details of Example 2 are as follows.

  First, 200 parts by weight of silica as oxide-based particles and 200 parts by weight of titanium oxide as high dielectric constant particles were added to 100 parts by weight of epoxy resin, and mixed using a universal mixing stirrer. To this mixture, 10 parts by weight of a layered silicate compound not organically modified was added and mixed using a universal mixing stirrer. To this mixture, 86 parts by weight of an acid anhydride curing agent for epoxy resin and 1 part by weight of a curing accelerator for acid anhydride curing agent are added and mixed at 80 ° C. for 10 minutes to obtain a resin composition. Prepared.

  The resin composition thus adjusted was subjected to a curing treatment under the same conditions as in Example 1 to produce a target insulating material. This insulating material was subjected to the characteristic evaluation described later.

[Example 3]
In Example 3, except that the blending ratio of the inorganic particles deviates from the range shown in FIG. 2, the organically modified layered silicate compound and the coupling agent for surface treatment were produced by the same production process as in Example 1. Was added to the epoxy compound and shear mixed, followed by mixing of oxide-based particles and high dielectric constant particles. The details of Example 3 are as follows.

  First, 60 parts by weight of a layered silicate compound organically modified with quaternary ammonium ions and 1 part by weight of a silane coupling agent: γ-glycidoxy-propyltrimethoxysilane are added to 100 parts by weight of an epoxy resin, and shear force is applied. And mixed.

  To this mixture, 250 parts by weight of silica as oxide-based particles and 250 parts by weight of titanium oxide as high dielectric constant particles were added and mixed using a universal mixing stirrer. To this mixture, 86 parts by weight of an acid anhydride curing agent for epoxy resin and 1 part by weight of a curing accelerator for acid anhydride curing agent were added and mixed at 80 ° C. for 10 minutes to obtain a resin composition. Was prepared.

  The resin composition thus adjusted was subjected to a curing treatment under the same conditions as in Example 1 to produce a target insulating material. This insulating material was subjected to the characteristic evaluation described later.

[Comparative Example 1]
As Comparative Example 1, except that no layered silicate compound is used, oxide-based particles and high dielectric constant particles having the same blending ratio as in Example 1 are added to the epoxy compound together with a coupling agent for surface treatment. And mixed. Details of Comparative Example 1 are as follows.

  First, 200 parts by weight of silica as oxide-based particles, 100 parts by weight of titanium oxide as high dielectric constant particles, and 1 part by weight of silane coupling agent: γ-glycidoxy-propyltrimethoxysilane are added to 100 parts by weight of epoxy resin. And mixed using a universal mixing stirrer. To this mixture, 86 parts by weight of an acid anhydride curing agent for epoxy resin and 1 part by weight of a curing accelerator for acid anhydride curing agent were added and mixed at 80 ° C. for 10 minutes to obtain a resin composition. Was prepared.

  The resin composition thus adjusted was subjected to a curing treatment under the same conditions as in Example 1 to produce a target insulating material. This insulating material was subjected to the characteristic evaluation described later.

[Comparative Example 2]
As Comparative Example 2, except that high dielectric constant particles are not used, an organically modified layered silicate compound and a surface treatment using a layered silicate compound and oxide-based particles having the same mixing ratio as Example 1 are used. A coupling agent was added to the epoxy compound and shear mixed, followed by mixing of the oxide-based particles. Details of Comparative Example 2 are as follows.

  First, 10 parts by weight of a layered silicate compound organically modified with quaternary ammonium ions and 1 part by weight of a silane coupling agent: γ-glycidoxy-propyltrimethoxysilane are added to 100 parts by weight of an epoxy resin, and the shearing force is increased. Added and mixed.

  To this mixture, 250 parts by weight of silica as oxide-based particles was added and mixed using a universal mixing stirrer. To this mixture, 86 parts by weight of an acid anhydride curing agent for epoxy resin and 1 part by weight of a curing accelerator for acid anhydride curing agent were added and mixed at 80 ° C. for 10 minutes to obtain a resin composition. Was prepared.

  The resin composition thus adjusted was subjected to a curing treatment under the same conditions as in Example 1 to produce a target insulating material. This insulating material was subjected to the characteristic evaluation described later.

Table 1 below summarizes the blending compositions used in Examples 1 to 3 and Comparative Examples 1 and 2 described above, the blending ratios, and the differences in the manufacturing process.

[Method for measuring physical properties of insulating materials obtained in Examples and Comparative Examples]
Next, the linear expansion coefficient, dielectric constant, fracture toughness, and resin viscosity of the insulating materials obtained in Examples 1 to 3 and Comparative Examples 1 and 2 described above were measured by the following methods.

<Measuring method of linear expansion coefficient>
The linear expansion coefficient was calculated | required with the thermomechanical analyzer (TMS-110: Seiko Instruments) using the test piece of 5 mm long x 5 mm wide x 15 mm in height. The measurement temperature range was 20 to 200 ° C., and the heating rate was 2 ° C./min.

<Measurement method of dielectric constant>
In accordance with JIS-K6911, a dielectric constant was measured by a GR bridge (GR1616: General Radio) at room temperature using a circular test piece having a diameter of 100 mm and a thickness of 2 mm. The measurement frequency is 60 Hz.

<Measurement method of fracture toughness>
According to ASTM D5045-91, an initial crack was generated in the compact tension test piece, a tensile load was applied, and the fracture toughness value (K _IC ) was calculated from the load when the crack progressed and broke. The moving speed of the crosshead is 1 mm / min, and the measurement temperature is room temperature.

<Measurement method of resin viscosity>
After dispersing each particle in the epoxy resin compound and subsequently adding an epoxy resin curing agent, the resin composition before heat curing was warmed to 60 ° C., and the resin viscosity was measured with a B-type viscometer.

[Measurement results of physical properties of insulating materials obtained in Examples and Comparative Examples]
Table 2 below shows the measurement results obtained by the above measurement method. As the measurement results in Table 2 show, the insulating material according to Examples 1 to 3 of the present invention has a thermal expansion coefficient comparable to that of copper as a conductor material, compared with the insulating material according to Comparative Examples 1 and 2. It can be seen that it is small, has a high dielectric constant, has high fracture toughness, and has a viscosity suitable for casting operations. In the following, the operations and effects of the present invention will be described in more detail by comparing and referring to Examples 1 to 3 and Comparative Examples 1 and 2 in Tables 1 and 2.

[Comparison between Example 1 and Comparative Examples 1 and 2]
First, by comparing Example 1 and Comparative Examples 1 and 2 in Tables 1 and 2, the action and effect of filling three types of inorganic particles, a layered silicate compound, an oxide-based particle, and a high dielectric constant particle, are shown. Can be explained. That is, as shown in Table 1, the insulating material according to Example 1 is filled with three types of layered silicate compound, oxide-based particles, and high dielectric constant particles. On the other hand, in Comparative Example 1, only the oxide particles and the high dielectric constant particles are filled, and the layered silicate compound is not filled. In Comparative Example 2, only the layered silicate compound and the oxide-based particles are filled, and the high dielectric constant particles are not filled.

  As shown in Table 2, in Example 1, the linear expansion coefficient is smaller than that of Comparative Example 1, and the fracture toughness is high. This is because the layered silicate compound dispersed on the nanoscale in the epoxy resin restrains the polymer chain of the epoxy resin and suppresses the movement of the molecular chain due to heat, thereby suppressing thermal expansion and causing cracks. In this case, the progress can be suppressed, which is considered to improve the fracture toughness. In Example 1, since the high dielectric constant particles are filled, the dielectric constant is higher than that of Comparative Example 2.

[Comparison between Example 1 and Example 3]
Next, by comparing Example 1 and Example 3 in Tables 1 and 2, the action and effect due to the limitation of the filling amount of inorganic particles (mixing ratio with respect to the epoxy compound) can be explained. That is, as shown in Table 1, the filling amount of the inorganic particles in Example 1 is within a desirable range shown in FIG. On the other hand, the filling amount of the inorganic particles in Example 3 deviates from the range shown in FIG.

  As shown in Table 2, the viscosity of the resin in Example 3 is significantly higher than the viscosity of the resin in Example 1 is sufficiently low. This means that the increase in the viscosity of the resin can be suppressed if the filling amount of the inorganic particles is within the desirable range shown in FIG. 2, while the increase in the viscosity of the resin is remarkable when the amount exceeds the range. ing. In addition, each physical property value other than the viscosity shown in Table 2 is not greatly different between Example 1 and Example 3. However, when the resin viscosity is very high as in Example 3, workability such as casting is improved. Is significantly reduced.

[Comparison between Example 1 and Example 2]
Subsequently, by comparing Example 1 and Example 2 in Tables 1 and 2, the layered silicate compound was shear mixed before the oxide-based particles and the high dielectric constant particles, and the layered silicate compound was quaternary ammonium ion. The effect | action and the effect by the point which carries out organic modification by (1) and the point which surface-treats an inorganic particle with a silane coupling agent can be demonstrated. That is, as shown in Table 1, the manufacturing process of Example 1 has these characteristics, whereas the manufacturing process of Example 2 does not have these characteristics.

  First, in Example 1, compared with Example 2, the linear expansion coefficient is small and the fracture toughness is high. That is, in Example 1, since the layered silicate compound having a nano-size particle size is dispersed in the epoxy compound by shear mixing before the oxide-based particles having a large particle size and the high dielectric constant particles, It can be considered that the layered silicate compound can be efficiently mixed with a shearing force and can be uniformly dispersed in the epoxy compound, so that the linear expansion coefficient is small and the fracture toughness is high. On the other hand, in Example 2, since the oxide-based particles and the high dielectric constant particles are dispersed in the epoxy compound, the layered silicate compound is dispersed by a general-purpose mixing device that does not apply a large shearing force. Since the silicate compound cannot be dispersed as uniformly as in Example 1, it is considered that the linear expansion coefficient is slightly large and the fracture toughness value is slightly small.

  Furthermore, in Example 1, since the layered silicate compound is organically modified with quaternary ammonium ions, the surface energy of the silicate layer is reduced by the quaternary ammonium ions, and the interlayer becomes an oleophilic atmosphere. In Example 1, due to the effect of such organic modification with quaternary ammonium ions, the affinity of the layered silicate compound to the epoxy resin is increased, and the layered silicate compound is peeled off between the layers by applying shear stress and mixing. Thus, it is considered that each layer can be more uniformly dispersed in the insulating material. On the other hand, in Example 2, since the layered silicate compound is not organically modified with quaternary ammonium ions, the effect of organic modification with such quaternary ammonium ions cannot be obtained.

  In Example 1, the inorganic particles are surface-treated with a silane coupling agent. However, since such a surface treatment chemically bonds the interface between the inorganic particles and the resin, the polymer chain of the epoxy resin is restrained. It becomes easy, the movement of the molecular chain due to heat can be suppressed, and the adhesion of the particle / resin interface, which is a weak point of crack propagation, can be strengthened. On the other hand, in Example 2, since the surface treatment of the inorganic particles with the silane coupling agent is not performed, the above-described effect due to the surface treatment cannot be obtained. This is also considered to contribute to the fact that the fracture toughness value of Example 1 is higher than that of Example 2.

[Other Embodiments]
Note that the present invention is not limited to the above-described embodiments and examples, and various other modifications can be implemented within the scope of the present invention. For example, the types and compositions of materials and the types of devices shown in the embodiments and examples are merely examples, and the types and compositions of materials specifically used and specific types of devices can be selected as appropriate. In addition, specific manufacturing processes, processing conditions, and the like can be selected as appropriate in accordance with the type and composition of the material used, the type of apparatus, and the like.

The schematic diagram which shows one Embodiment of the resin composition by this invention. The conceptual diagram which shows the desirable range of the filling amount of the layered silicate compound in one embodiment of this invention, an oxide type particle | grain, and a high dielectric particle. The flowchart which shows an example of the manufacturing process of the resin composition by this invention. The schematic diagram which shows the vacuum valve molded with the resin composition by this invention. The schematic diagram which shows the insulating spacer produced with the resin composition by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Resin composition 2 ... Epoxy resin 3 ... Layered silicate compound 4 ... Oxide type particle | grain 5 ... High dielectric constant particle 41 ... Vacuum valve 42 ... Casting insulator 51 ... High voltage conductor 52 ... Insulating spacer

Claims (6)

A layered silicate compound, oxide particles composed of silica, and high dielectric constant particles composed of titanium oxide are dispersed in an epoxy resin composed of an epoxy compound having two or more epoxy groups per molecule and a curing agent for epoxy resin. In the resin composition obtained,
For 100 parts by weight of the epoxy compound,
10 to 60 parts by weight of the layered silicate compound, 200 to 250 parts by weight of the oxide-based particles, and 200 to 250 parts by weight of the high dielectric constant particles, respectively, The total filling amount of dielectric particles is 500 parts by weight or less. 2. The layered silicate compound is at least one selected from a mineral group consisting of a smectite group, a mica group, a vermiculite group, and a mica group, or a mixture of two or more types. Resin composition. The layered silicate compound is organically modified with a quaternary ammonium ion,
Prior to the oxide-based particles and the high dielectric constant particles, dispersed in the epoxy compound by shear mixing,
And the surface of the said layered silicate compound, the said oxide type particle | grain, and the said high dielectric constant particle is modified by the coupling agent. The resin composition of Claim 1 or Claim 2 characterized by the above-mentioned. . In an electrical device having a casting member or a structural member that performs electrical insulation,
The said casting member or structural member hardens | cures the resin composition of any one of Claim 1 thru | or 3. Electric equipment characterized by the above-mentioned. In a method for producing a resin composition by dispersing a material for improving physical properties in an epoxy resin comprising an epoxy compound having two or more epoxy groups per molecule and an epoxy resin curing agent,
After the layered silicate compound is dispersed by shear mixing in the epoxy compound, the curing agent for epoxy resin is added to a mixture in which oxide particles made of silica and high dielectric constant particles made of titanium oxide are dispersed. ,
For 100 parts by weight of the epoxy compound,
10 to 60 parts by weight of the layered silicate compound, 200 to 250 parts by weight of the oxide-based particles, and 200 to 250 parts by weight of the high dielectric constant particles, respectively, The total filling amount of dielectric constant particles is 500 parts by weight or less. A method for producing a resin composition, comprising: The layered silicate compound is previously organically modified with a quaternary ammonium ion before the dispersion,
6. The method for producing a resin composition according to claim 5, wherein surfaces of the layered silicate compound, the oxide-based particles, and the high dielectric constant particles are modified with a coupling agent during the dispersion. .

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