JPS6144365B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to an electrically insulating material, and more particularly to an electrically insulating material that has good storage stability and excellent electrical properties. [Technical background of the invention and its problems] Conventionally, electrical insulating materials for generators, electric motors, etc.
Prepreg tapes are used, such as mica tapes impregnated with thermosetting resin compositions. When such a prepreg tape is used, it is heated and cured after covering a member to be insulated. The requirements for such electrically insulating materials are:
It has good electrical insulation properties, is highly flexible to improve workability, and does not require a separate material between electrically insulating materials to prevent them from sticking together (separateless) from the viewpoint of workability. It is. A conventionally used electrical insulating material includes, for example, a laminated mica paper impregnated with a resin composition comprising an epoxy resin and an acid anhydride. However, in such prepreg tapes, it is difficult to suppress the viscosity of the tape surface, so it is necessary to insert a separate material between the tapes, and it is necessary to use a highly flexible tape. The problem is that it is difficult to obtain. Therefore, in practice, glass cloth, nonwoven fabric, heat-resistant synthetic paper, etc. are attached to both the front and back sides of laminated mica paper impregnated with a resin composition, or a film or paper with release properties is inserted between the tapes. Then, the tape is wound around the core. The manufacturing process for such electrically insulating materials is complicated, and separates must be removed before use, which poses problems in terms of workability. [Object of the Invention] The object of the present invention is to solve the conventional problems and to provide a highly flexible and separate-less product using a resin composition mainly composed of an epoxy resin and an acid anhydride as an impregnating resin. The object of the present invention is to provide an electrically insulating material that exhibits excellent electrical properties when cured by heating. [Summary of the Invention] The electrical insulating material of the present invention includes a base material made of laminated mica paper and a reinforcing material, an epoxy resin, an acid anhydride,
It is characterized by being impregnated with a resin composition comprising an organosilicon compound and an organoaluminium compound having a hydrolyzable group. In the following, the invention will be explained in more detail. The laminated mica paper used as the base material of the electrically insulating material of the present invention may be of any material as long as it is normally used for electrically insulating purposes, such as soft or hard mica, baked After cutting into pieces by or by physical method,
Examples include those made into paper form. In addition, the reinforcing material for the base material is used for the purpose of reinforcing the mechanical strength of the laminated mica paper, and examples include glass cloth, polyimide film, aramid paper, etc., which are highly flexible and heat resistant. Examples include those with gender. In the present invention, the resin composition used to impregnate the base material consists of the following. The epoxy resin used in the present invention is 1
There is no particular restriction as long as it has at least one epoxy group in the molecule and is generally known as an epoxy resin, such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, Phenol novolac type epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin such as triglycidyl isocyanurate and hydantoin epoxy, hydrogenated bisphenol A type epoxy resin, propylene glycol-diglycidyl ether and pentaerythritol-polyglycidyl ether aliphatic epoxy resins such as, glycidyl ester type epoxy resins obtained by the reaction of aromatic, aliphatic or alicyclic carboxylic acids with epichlorohydrin, reaction products of O←allyl-phenol novolak compounds and epichlorohydrin. It is a reaction product of epichlorohydrin and glycidyl ether type epoxy resin, which is a glycidyl ether type epoxy resin, and an allyl bisphenol compound having an allyl group at the O-position (3, 3', 5 and 5' position) of each hydroxyl group of bisphenol A. Examples include certain glycidyl ether type epoxy resins, and one or more resins selected from the group consisting of these resins are used. Among these, among others, epoxy equivalent 170
It is preferred to use liquid bisphenol A type epoxy resins having an epoxy equivalent weight of 170 to 190. The epoxy resin is preferably blended in the resin composition in an amount of 20 to 80% by weight, more preferably 40 to 60% by weight. The acid anhydride used in the present invention is not particularly limited as long as it is an aliphatic, alicyclic or aromatic carboxylic anhydride or a substituted carboxylic anhydride thereof; examples thereof include maleic anhydride, anhydride Succinic acid, methylsuccinic anhydride, dodecynylsuccinic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, nadic anhydride , methylnadic anhydride, 3,3',4,4'-benzophenonetetracarboxylic anhydride, tetrapromphthalic anhydride, and chlorendicic anhydride, and one or more selected from the group consisting of these. Two or more types are used. Among these, it is particularly preferable to use methylnadic anhydride because it is liquid. Such acid anhydride is preferably blended in the resin composition in an amount of 5 to 60% by weight, and more preferably,
It is 20-50% by weight. The organosilicon compound having a hydrolyzable group used in the present invention constitutes the curing catalyst system of the resin composition according to the present invention, and is hydrolyzed at a certain temperature or higher in the presence of water to form silanol hydroxyl groups.

There are no particular limitations as long as the compound has a residue directly bonded to a silicon atom that forms the formula.
Examples of such organosilicon compounds include organosilane compounds and organosiloxane compounds described below. The organosilane compound having a hydrolyzable group used in the present invention has the following general formula [] [In the formula, R is a hydrolyzable group, an alkoxyl group having 1 to 5 carbon atoms; an aryl group such as a phenoxy group, tolyloxy group, p-methoxyphenoxy group, p-nitrophenoxy group, p-chlorophenoxy group Oxy group; araloxy group such as benzyloxy group, phenethyloxy group; acetoxy group,
Acyloxy groups such as propionyloxy group, butyryloxy group, benzoyloxy group, phenylacetoxy group, formyloxy group; or the following formula (In the formula, R' and R'' may be the same or different and represent an alkyl group having ¹ to ⁵ carbon atoms.) X ³ may be the same or different, and have 1 to 12 carbon atoms
alkyl groups; phenyl group, tolyl group, p-methoxyphenyl group, p-nitrophenyl group, p-
Aryl group such as chlorophenyl group; benzyl group,
Aralkyl groups such as phenethyl group, p-methoxybenzyl group, p-methylbenzyl group; alkenyl groups such as vinyl group, allyl group, propenyl group, butenyl group; or acyl groups such as acetyl group, benzoyl group, trifluoroacetyl group etc., p, q
and r is an integer from 0 to 3. However, p+q+r
≦3. ]. These organosilanes include, for example, trimethylmethoxysilane,
Triethylmethoxysilane, tripropylmethoxysilane, tributylethoxysilane, triphenylmethoxysilane, triphenylethoxysilane, tri(p-methoxyphenyl)methoxysilane, tri(p-methoxyphenyl)ethoxysilane, tri(p-nitrophenyl) ) Methoxysilane, triacetylmethoxysilane, triacetylethoxysilane, diphenylmethylmethoxysilane, diphenylethylethoxysilane, diphenylpropylethoxysilane, 2-butenyldiphenylmethoxysilane, di(2-pentenyl)phenylethoxy Silane, phenyldipropylmethoxysilane, phenyldivinylpropoxysilane,
Phenylvinylmethylmethoxysilane, triisobutylacetoxysilane, triphenylacetoxysilane, diphenylmethylacetoxysilane,
Diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldipropoxysilane, di(p-chlorophenyl)diethoxysilane, p-
Methylbenzyltrimethoxysilane, trifluoroacetyltrimethoxysilane, (In the formula, φ represents a phenyl group. The same applies hereinafter.) and etc. Furthermore, the organosiloxane compound having a hydrolyzable group used in the present invention has a molecular chain consisting of a bifunctional unit represented by the following formula [] and/or a trifunctional unit represented by the following formula [], Depending on the case, it may contain a tetrafunctional unit represented by the following formula [], and is a linear, branched or cyclic siloxane, and when the siloxane chain has a terminal, it may contain a tetrafunctional unit represented by the following formula []. It is capped by the monofunctional unit shown.

【formula】

【formula】

【formula】

[Formula] [In the formula, Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ and Y ⁶ may be the same or different, and are a hydrolyzable group; an alkyl group having 1 to 5 carbon atoms; Aryl groups such as phenyl group, tolyl group, p-methoxyphenyl group, p-chlorophenyl group, p-nitrophenyl group, p-cyanophenyl group; Aralkyl groups such as benzyl group, phenethyl group, p-methoxybenzyl group;
It represents an alkenyl group such as a vinyl group, allyl group, propenyl group, butenyl group; or an acyloxy group such as an acetyl group, benzoyl group, trifluoroacetyl group, etc. ] At least one of the above structural units contains one or more hydrolyzable groups. Among these organosiloxane compounds, it is particularly preferable to use those having a degree of polymerization of 50 or less and an equivalent weight of a hydrolyzable group of 1000 or less, and more preferably one having an equivalent weight of a hydrolyzable group of 50 to 500. It is something. Examples of such organosiloxane compounds include 1,3-dimethoxy-1,3-dimethyl-
1,3-diphenyldisiloxane, 1,5-diethoxy-1,3,5-trimethyl-1,3,5-
Triphenyltrisiloxane, 1,7-dimethoxy-1,3,5,7-tetramethyl-1,3,
5,7-tetraphenyltetrasiloxane, 1,
3-dimethoxy-tetraphenyldisiloxane,
1,5-dimethoxy-3,3-dimethyl-1,
1,5,5-tetraphenyltrisiloxane,
1,3,5-trimethoxy-pentaphenyltrisiloxane, 1,5-dimethoxy-hexa(p-
methoxyphenyl)trisiloxane,

【formula】

In addition, silicone resins having trade names such as Q1-3037 (methoxy group content: 18% by weight) can also be used. As the organosilicon compound having a hydrolyzable group used in the present invention, one or more compounds selected from the group consisting of the above-mentioned organosilanes and organosiloxane compounds are used. Such an organosilicon compound is preferably blended in an amount of 0.0001 to 30% by weight, more preferably 0.01 to 10% by weight, based on the epoxy resin. The organoaluminum compound used in the present invention constitutes another component of the curing catalyst of the resin composition according to the present invention. The organoaluminum compound is preferably an aluminum chelate compound in which various organic groups are coordinated to an aluminum atom. Examples of ligands that coordinate to aluminum atoms include alkyl groups having 1 to 5 carbon atoms; haloalkyl groups having 1 to 5 carbon atoms; carbon atoms such as methoxy, ethoxy, and isopropoxy groups. 1 to 5 alkoxyl groups; Acyloxy groups such as acetoxy, propionyloxy, isopropionyloxy, butyryloxy, stearoyloxy, and benzoyloxy groups; phenoxy, tolyloxy, p-methylphenoxy, p-methoxyph Aryloxy groups such as enoxy groups; and acetylacetone, trifluoroacetylacetone, pentafluoroacetylacetone, ethylacetoacetate, salicylaldehyde, diethylmalonate, β-diketone, and the like. Specifically, for example, tris(acetylacetonato)aluminum, tris(ethylacetoacetato)aluminum, tris(diethylmalonato)aluminum, mono(ethylacetoacetato)aluminum diisopropoxide, salicylaldehydatoaluminum, etc. One or more types selected from the group consisting of these are used. The organic aluminum compound is preferably blended in an amount of 0.001 to 10% by weight, more preferably 0.1 to 6% by weight, based on the epoxy resin. The electrical insulating material of the present invention is preferably one in which the base material is impregnated with 1 to 150% by weight, more preferably 10 to 150% by weight of the above-described resin composition.
~85% by weight. The resin composition to be impregnated into the base material is solvent-free because it does not require drying of volatile components for the purpose of impregnating a large amount of it, and the electrical and physical properties of the heat-cured product are excellent. It is preferable to use a type. However, the electrical insulating material of the present invention uses a resin composition such as
There is no problem even if the base material is impregnated with a relatively low boiling point solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, etc. do not have. [Effects of the Invention] The electrical insulating material of the present invention is produced by using a resin composition containing an epoxy resin, an acid anhydride, an organosilicon compound, and an organoaluminum compound as a resin composition to be impregnated into a mica tape. Surface tackiness is extremely reduced. Therefore, it can be manufactured without separates, and there is no need to remove the separates during use, resulting in good workability and extremely excellent workability. Furthermore, since it can be impregnated with a solvent-free resin composition, when it is made into a prepreg tape, there is no volatilization of the solvent, and it has stable performance. Furthermore, the storage stability of this prepreg tape is extremely good, with temperatures ranging from 10 to 15℃.
The rate of change in flexibility after being stored in a cool, dark place for three months was within 10%, and the impregnated resin had an appropriate amount of heat flow when heated and cured, and had extremely excellent electrical insulation properties. In the following, the present invention will be explained in more detail with reference to Examples. In the description, all parts represent parts by weight. Preparation Example 1 Into a 5-volume flask, put 2250 parts of Epicote 152 (manufactured by Ciel Chemical Co., Ltd.) as an epoxy resin, 250 parts of Epicote 1001 (same as above) as an epoxy resin, and 12.5 parts of tris(acetylacetonato)aluminum as an organic aluminum compound. , while stirring the contents 90
Hold at °C for 20 minutes. The contents were then cooled to 60°C, and methylnadic anhydride 2125 was added as the acid anhydride.
and 25 parts of triphenylethoxysilane as an organosilicon compound, and the contents were mixed with 60 parts while stirring.
After being held at ℃ for 20 minutes, it was cooled to room temperature to obtain a solvent-free resin composition. The viscosity of this resin composition was measured using a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd.) by placing 250 parts of the sample in a 0.3 peak and keeping the temperature of the contents constant using a constant temperature water bath. As a result, 32poise at 30℃, 60℃
So it was 2poise. Next, this resin composition was applied to a thickness of 1 mm and 2 mm.
After molding into a plate-like body having the following properties, the mixture was heated at 150°C for 5 hours and then at 180°C for 24 hours to obtain a cured product. Regarding this plate-shaped cured product, the volume resistivity value,
The dielectric loss tangent (tanδ) value and bending strength are respectively
Measurements were made in high temperature atmospheres of 20°C and 180°C. The results are shown in the table.

[Table] Furthermore, the degree of linear thermal expansion of the resin composition cured at 200°C for 72 hours is the glass transition point.
It was confirmed that the temperature below Tg was 5.26×1 ^-5 /°C, and the temperature above Tg was 18.1×10 ^-5 /°C, and Tg was 179°C. Example 1 Appropriate amounts of a resin composition obtained in the same manner as in Preparation Example 1 were placed in a tank and maintained at 60°C. A rotating roll was placed in this tank, and using this rotating roll, the resin composition was applied to one side of a Kapton film having a thickness of 0.025 mm and a width of 500 mm. Then,
After laminating mica paper on this coated surface, it was dried in a drying oven at 120° C. for 20 minutes and wound around a core to obtain a prepreg tape. At this time, the resin composition was adjusted to be 15 to 20% by weight based on the Kapton mica base material. The obtained prepreg tape had a finished thickness of 0.13 mm.
The rolled prepreg tape was cut into a width of 25 mm to obtain a Kapton aggregated mica prepreg tape. The surface of such prepreg tape has almost no adhesiveness, and the tape can be easily undone, and its flexibility is
When measured by the method, it was confirmed to be 0.85. Example 2 An appropriate amount of the resin composition obtained in the same manner as in Preparation Example 1 was put into a tank equipped with a rotating roll, and the mixture was heated for 60 minutes.
It was kept at ℃. The glass cloth tape was placed in contact with a rotating roll, and the resin composition was applied to one side by moving the glass cloth tape. After laminating mica paper on this coated surface, it was dried in a drying oven at 120° C. for 40 minutes, cooled to near room temperature, and wound around a core to obtain a prepreg tape. At this time, the resin composition was adjusted to be 64 to 69% by weight based on the laminated mica glass cloth base material. The obtained prepreg tape had a finished thickness of 0.27 mm. The rolled prepreg tape was cut into a width of 30 mm to obtain a laminated mica glass cloth prepreg tape. It was confirmed that the obtained prepreg tape had extremely good unwinding properties, and that the workability during winding work was good. Furthermore, when its flexibility was measured by the SH method, it was 1.05, confirming that it was highly flexible. Using the above-mentioned laminated mica glass cloth prepreg tape, it was wrapped around a rectangular aluminum test piece 12 times with a 1/2 wrap, at 150°C for 5 hours, and then
It was heated and cured at 180°C for 48 hours. When the dielectric loss tangent (tan δ) value of this cured product was measured, it was 0.25% at 20°C and 1.5% in a high temperature atmosphere of 180°C, confirming that it has excellent electrical properties. Preparation Example 2 Into a flask with a capacity of 1, 272 parts of Epicote 154 (manufactured by Ciel Kagaku Co., Ltd.) as an epoxy resin, 182 parts of Epicote 1001 (same as above) and 2.2 parts of tris(acetylacetate)aluminum as an organoaluminum compound were added. While stirring things, 90~
Hold at 100℃ for 20 minutes, confirm that the contents have become transparent, and then cool to 60℃. Next, 170 parts of methylnadic anhydride was added as an acid anhydride, and triphenylethoxysilane was added as an organosilicon compound.
Add 8.3 parts and 69 parts of methyl ethyl ketone as a solvent and stir the contents at a temperature of 50-60 °C for 30 minutes.
After holding for a minute, the mixture was cooled to room temperature to obtain a solvent-based resin composition. The viscosity of this resin composition was measured in the same manner as in Preparation Example 1, and was found to be 6 poise at 40°C. Next, this resin composition was applied onto an aluminum plate so that the coating thickness of the cured product was 0.08 to 0.1 mm, and after 3 hours at 150°C, it was heated at 180°C for 24 hours to cure. I forced it. Regarding this cured product,
When we measured the dielectric loss tangent value, it was 0.43% at 20℃.
In a high temperature atmosphere of 180°C, it was 3.45%. Example 3 A resin composition obtained in the same manner as in Preparation Example 2 was applied to a base material consisting of laminated mica paper and glass cloth in the same manner as in Example 2 so that the resin amount was 60 to 67% by weight. After impregnating the prepreg tape, it was dried at 120 to 130°C for 30 to 45 minutes and wound around a core to obtain a prepreg tape. This prepreg tape has a width of 30
It was confirmed that the surface of the sample cut into mm pieces showed a tack-free B-stage state and was highly flexible. Apply this separate-less prepreg tape to a rectangular wire-shaped aluminum test piece in 1/2 laps.
The material was wound around the film and heated at 180°C for 24 hours to cure it. When the dielectric loss tangent value of such a cured product was measured,
It was 0.53% at 20°C and 3.4% in a high temperature atmosphere of 180°C, and although it was slightly inferior to that of Example 2, it was confirmed that it had excellent electrical properties.

Claims (1)

[Claims] 1. An electrical insulation characterized by impregnating a base material made of laminated mica paper and a reinforcing material with a resin composition made of an epoxy resin, an acid anhydride, an organosilicon compound having a hydrolyzable group, and an organoaluminium compound. material.