JPS605209B2 - electrical insulation wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides improved heat resistance, mechanical properties, and electrical insulation properties obtained by winding mica tape, which has a long shelf life below room temperature and hardens at relatively low temperatures. Concerning the excellent electric wire theory.

Recently, in response to the miniaturization of electrical equipment, electrical insulators are required to have high heat resistance, and progress is being made in the development of class H insulation that can be operated continuously for 180 cm or less.

Conventionally, aromatic polyimide resins, silicone resins, and the like are known as heat-resistant resins for H type insulation. However, this polyimide resin uses a gutter solvent, which poses problems in terms of occupational health, and the final curing temperature is high, and water is generated during the curing reaction process, resulting in the formation of a delicate insulating structure. However, silicone resins require complicated working conditions, and their applications have been limited to electric wires and films.On the other hand, silicone resins also have a high final curing temperature, and the insulators after curing have poor mechanical properties and electrical properties. The problem was that the insulation properties were slightly inferior.
In addition, recently, materials made from maleimide compounds have become known for H type insulation. However, when this maleimide-based compound is used as a raw material, the resin produced by the curing reaction is mechanically brittle and has a disadvantage of being impractical. In view of these points, the present inventors have conducted intensive studies and found that a composition consisting of a maleimide compound and an epoxy resin can be used as a curing catalyst for aluminum compounds such as aluminum triacetylacetonate. It has been found that a cured resin with good mechanical strength and excellent heat resistance can be produced when a heat curing reaction is carried out in the presence of the compound.

However, in this case, the heat curing temperature is usually 150 to 2500.
0, reaction time of several hours to several tens of hours is required. As a result of further investigation, the present inventors developed a composition system consisting of a maleimide compound, an epoxy resin, and an aluminum compound.
When a small amount of a silane compound or polysiloxane compound containing a hydroxyl group is added as a curing accelerator,
It has been found that it is stable at room temperature and has a long shelf life, but exhibits a remarkable curing accelerating effect at moderate temperatures, cures in a short time, and exhibits excellent heat resistance without mechanical brittleness. . For example, Epicort 152 (product name,
Shell Chemical Co., Ltd.) 8 parts by weight and 2 parts by weight of N.N'-methylene di-P-phenylene bismaleimide, and 0 parts by weight of aluminum triacetylacetonate.
．． 1 part by weight, hydroxyl group-containing polysiloxane compound SH6018 (trade name, Toray Silicone Co., Ltd.) 0.
The composition to which 1 part by weight has been added is dissolved in methyl ethyl ketone, and this solution is impregnated into a woven glass fabric bagged mica sheet and dried for a short time at 50 to 70 qo.

It was discovered that the mica tape thus obtained has a shelf life of 3 months or more at room temperature and gels in a few minutes to several tens of minutes at 90 to 110°C. The present invention uses a brypreg-like mica tape that has a long shelf life at room temperature and gels in a short time at a relatively low temperature. The purpose is to provide.

To explain the present invention below, the present invention provides a resin composition containing as essential components a maleimide compound, an epoxy resin, an aluminum compound as a curing catalyst, and a hydroxyl group-containing silane compound or polysiloxane compound as a curing accelerator. This is an electrically insulated wire ring characterized by being made by winding a prepreg-like mica tape containing as an adhesive and curing it by heating.

In the present invention, the maleimide compound used as a component of the mica adhesive has the general formula (where X is a divalent hydrocarbon such as an alkylene group, a cycloalkylene group, or a monocyclic or polycyclic arylene group). group, or one CH
Divalent hydrocarbon groups bonded by divalent atomic groups, such as This is a maleimide compound obtained by the reaction of a mixed polyamine represented by the number (number) with maleic anhydride.

Examples of maleimide compounds of this type include N.N'-phenylene bismaleimide, N.N'-hexamethylene bismaleimide, N.N'-methylene di-P-phenylene bismaleimide, and N.N'-oxydi-P-phenylene bismaleimide. Nylene bismaleimide, N.N'-4.4'-penzophenone-bismaleimide, N.N'-P-diphenylsulfonemaleimide, N.N'-(3.3-dimethyl)-
Methylene di-P-phenylene bismaleimide, N/N
There are reaction products of the above-mentioned mixed polyamines and maleic anhydride, including '-(3,3-diethyl)-methylene di-P-phenylene bismaleimide and N.N-methatolylene di-maleimide. Furthermore, the maleimide compounds used in the present invention also include maleimide compounds synthesized by reacting with polyamines in place of other acid anhydrides within 60 mol% of maleic anhydride. Examples of other acid anhydrides used in combination with maleic anhydride used in the synthesis of the maleimide compound of the present invention include the following.

3 (or 4)-methyl-tetrahydrophthalic anhydride, tetrahydro-phthalic anhydride, nadic acid anhydride,
These include methylnadic anhydride, hexahydro-phthalic anhydride, dodecyl-succinic anhydride, succinic anhydride, methyl-monosuccinic acid, octadecyl-mono-hydrosuccinic acid, and the like.

On the other hand, examples of polyamine compounds include the following.

4,4'-diaminodiphenylmethane, 4,4-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ketone, o(
or m,p)-phenylenediamine, 3,3-dimethyl-4,4-diaminodiphenylmethane, 3,3-diethyl-4,4-diaminodiphenylmethane, 2,2
-bis-(4-aminophenyl)-propane, 4.4
-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, o (or m, p) xylylene diamine, phenylindane diamine, 1,1'-bis(p)
-aminophenyl)-phthalene, 4,4-methylene-bis(2-chloroaniline), 1,3-bis(aminomethyl)-cyclohexane, 1,4-diaminocyclohexane, 2,6-diaminopyridine 2,5-bis-(metamino These include phenyl)-1,3,4-oxadianol, 3,5-diamino1,2,4-triazole, and bis-p-(4-aminophenoxy)-benzene.

These bismaleimide compounds may be used alone or in a mixture of two or more, and monomaleimides such as N-arylmaleimide, N-propylmaleimide, N-hexylmaleimide, N-phenylmaleimide, etc. You may substitute with a compound. In the present invention, examples of epoxy resins constituting other components of the mica adhesive include the following.

That is, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, complex ring-containing epoxy resin such as triglycidyl isocyanate and hydantoin epoxy, Water-added bisphenol A type epoxy resins, aliphatic epoxy resins such as propylene glycol-dicrydyl ether and pentaerythritol-polyglycidyl ether, aromatic, aliphatic or cyclic carboxylic acids and epichlor. Epoxy resin obtained by reaction with hydrin, spiro ring-containing epoxy resin, glycidyl ether type epoxy resin which is a reaction product of orthoarylphenol novolak compound and epichlorohydrin, and the respective hydroxyl groups of bisphenol A. These include glycidyl ether type epoxy resin, which is a reaction product of a diallylbisphenol compound having an allyl group at the ortho position of , and epichlorohydrin. In the present invention, the above maleimide compound,
The composition ratio of the epoxy resin is appropriately selected depending on the application, desired heat resistance, etc., but is generally selected as follows.

That is, the composition ratio of the maleimide compound is preferably selected to be 5 to 95% by weight, and the composition ratio of the epoxy resin is preferably selected to be 5 to 95% by weight. Further, in the present invention, examples of the aluminum compound as a curing catalyst used in coexistence with a silane compound containing a hydroxyl group or a polysiloxane compound include the following.

That is, the general formula (wherein R,, R2 are alkyl groups and B
is a general formula in which R3 to R8 are ligands selected from the group consisting of alkyl groups, e and f are positive numbers from 0 to 3, and e+f does not exceed 3). It is a compound.

Among these aluminum compounds, aluminum trialkylacetoacetate, aluminum trisacetylacetonate, aluminum alcoholate, aluminum acylate, etc. are particularly useful, and are usually about 0.0001 to 5 parts by weight per 100 parts by weight of the resin composition of the present invention. be selected.

On the other hand, in the present invention, examples of the hydroxyl group-containing silane compound or polysiloxane compound used as a curing accelerator in coexistence with an aluminum compound include the following. That is, the general formula (wherein R, R
' is an alkyl group, phenyl group, aralkyl group, pinyl group, or allyl group, which may be the same or different, and q
, r are positive integers from 0 to 3, and q+r does not exceed 3.

) or the general formula (wherein R
, ~R7 represents a monovalent organosiloxane containing an alkyl group, a phenyl group, a vinyl group, an aralkyl group, an allyl group, or a hydroxyl group, but does not contain it, and may be the same or different, e, t, x, y are positive integers between 0 and 2, s+t and x+y do not exceed 2, and u and w are between 0 and 2.
indicates a positive integer. a and b represent 0 or a positive integer of 1 or more. ) There are polysiloxane compounds shown by These organosilanol compounds usually have a resin composition of the present invention, that is, a total of 100% of the maleimide compound and the epoxy resin.
It is preferable to select an amount of at least about 0.0001% by weight based on the weight part, and it may be up to about 5% by weight from the standpoint of promoting curing. On the other hand, in the present invention, radical polymerization initiators such as penzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, azobisisoputyronitrile, methyl ethyl ketone peroxide, and tertiary butyl perbenzoate are used as needed under the molding conditions. is selected as appropriate depending on the purpose of use, but it is usually preferably selected in an amount of about 0.05 to 3 parts by weight based on 100 parts by weight of the resin composition of the present invention. Furthermore, in the present invention, in order to improve the compatibility of the maleimide compound with the epoxy resin and the silane compound or polysiloxane compound, frifuryl alcohol may be added as necessary.

The amount of furfuryl alcohol added is usually preferably selected to be 0.4 equivalent or less based on the active double bond equivalent of the maleimide compound. The reason for this is that if the amount is selected to be 0.4 equivalent or more, the active double bonds of the maleimide compound will react with the frifuryl alcohol, and the heat resistance will tend to decrease when a cured resin is formed. The heat-resistant resin composition as an adhesive according to the present invention has a viscosity that varies depending on the selection of the composition ratio, etc., but as a so-called solvent-free type, it is not only suitable for infiltrating mica sheets, but also methyl ethyl ketone, dioxane, tetrahydrofuran, toluene, etc. Since it is easily dissolved in low boiling point solvents such as, it can be impregnated into mica sheets even in the form of a solvent.

The resin composition for the mica adhesive according to the present invention has good mutual compatibility and good wettability with the mica phosphor pieces and the backing material, so when it is thermally cured, it produces a ``void-free homogeneous insulation''. Furthermore, the insulating structure after hardening maintains and exhibits excellent heat resistance, mechanical properties, and electrical insulation properties, making it possible to provide an excellent dew-proof spring ring. explain.

Example 1 First, a maleimide compound was produced as follows.

That is, 50 parts by weight of maleic anhydride and 650 parts by weight of dimethylformamide were put into a reaction vessel and uniformly melted. A solution prepared by dissolving 496 parts by weight of 414-diaminodiphenylmethane in 30 parts by weight of dimethylformamide was added thereto over 30 minutes while observing the mixture. These mixed systems were heated to 60 to 70 qo and the reaction was continued for 1 hour to obtain an amic acid compound. Next, add acetic anhydride 637 to this reaction system.
．． 25 parts by weight and 82 parts by weight of anhydrous sodium acetate were added. After proceeding with the heating reaction at oq0 for 2 hours and 3 minutes, 8
℃, and pass this cooling solution through ice-cooled water.
A precipitate was obtained, and the product (precipitate) was washed repeatedly with ice-cooled water and then dried under reduced pressure to obtain bismaleimide A, which is the target maleimide compound, in a yield of 84%. 5 parts by weight of Bismaleimide AI, the maleimide compound thus obtained, and 10 parts by weight of Epiquat, a bisphenol A type epoxy resin.
01 (trade name, Shell Chemical Co., Ltd.) 25 parts by weight, novolak type epoxy resin Epicote 152 (trade name, Shell Chemical Co., Ltd.) 60 parts by weight, polysiloxane compound SH-60
18 (trade name, Toray Silicone Co., Ltd.) 2.0 parts by weight to 60
Melted in methyl ethyl ketone at a temperature of ~7000 °C,
A 5% by weight solution was prepared. Add to this solution 2. aluminum triethyl acetoacetate. Part by weight: TSR-160 (trade name, Toshiba Silicone Co., Ltd.), a polysiloxane compound with hydroxyl groups.2. Parts by weight of the tablets and parts by weight of dicumyl peroxide 4 were added and uniformly dissolved and mixed. This resin solution is impregnated and applied to a hard fired type laminated mica sheet with a thickness of about 0.1 yanagi, which is lined with a coarse glass cloth with a 35-shake diameter, and dried at 60 to 70 degrees for 5 to 2 minutes to form an adhesive. A prepreg mica sheet having a weight of about 45% was obtained. This pre-premica sheet was further cut into a width of 30 mm using a slitter to obtain a tape. This mica tape had a shelf life of over 3 months at room temperature. Next, as shown in FIG.
Wrap 5 times with heavy winding, and heat at 150°C for 1 to 10 minutes while applying a pressure of 25k9/min using a press or molding machine (not shown).
Mold for 2 hours.

Thereafter, it is heated and cured in an oven at 150° C. for about 10 hours to obtain an electrically insulating coil. The electrically insulated wire ring thus obtained showed high dielectric breakdown strength of 30KV' or higher using the short-time rise method, and higher bending strength of 15K9/square or higher compared to conventional silicone mica insulation. .

In addition, despite curing at a relatively low temperature and in a short time, the n6 (dielectric loss tangent) at 180 qo IKV/rib is within 10%, as shown in curve 1 in Figure 2, and the electrical loss at high temperatures is low. Few. Katta. Furthermore, after heating this electrically insulated wire ring at 22,500 for 1,000 hours, the dielectric breakdown voltage and bending strength were tested, and there was almost no difference from the initial value. There was also no significant increase in After the dielectric breakdown, the insulating layer was disassembled and visually observed, but no peeling of the insulating layer or carbonization of the resin was observed, indicating that the electrical insulating wire has excellent heat resistance and mechanical properties. It turned out that. Example 2 A polyamine MDA-150 (trade name, Mitsui Nisso Polyurethane Co., Ltd.) 90 having an amino/group content of 15.9% and a viscosity of 16,000 centipoise was placed in a reaction vessel equipped with a thickener, a thermometer, and a cooling tube. parts by weight, 40 parts by weight of sodium acetate and 130 parts by weight of dimethylformamide;
At 70:00, the mixture was heated and concentrated for 1 hour.

Thereafter, it was cooled to room temperature, and 900 parts by weight of maleic anhydride was added at a temperature maintained below 40 qo. After the addition was completed, the Nada group was continued for 1 hour, and then the temperature was raised to 80 to 90 qo and reacted for 2 hours. Ta. After cooling the above reaction system to room temperature, 6-
Bismaleimide, which is a reaction product, is obtained as a precipitate by dropping it into 8 times the amount of water, which is washed twice with 5000 ml of hot water and once with cold water, cleaned, and vacuum dried to obtain a maleimide compound. Bismaleimide B was obtained. Bismaleimide B, which is a maleimide compound thus obtained, was used in place of pismaleimide A in Example 1, and a resin solution was obtained under the same conditions as in Example 1 except for the following.

This resin solution was applied to a sheet of soft unfired laminated mica with a thickness of about 0.1 ribs lined with coarse glass cloth 35 mm thick, dried in an oven at 70 to 90 qo, and subjected to 8-stage pre-bregma. I got a ticket sheet. This mica sheet was further cut with a slitter to a width of 3 meters to obtain a mica tape. The mica tape at this time also had a shelf life of 3 months or more at room temperature. Using this pre-preg mica tape, in exactly the same manner as in Example 1, an exposure-proof line theory was obtained.

This electrically insulated wire ring has a n6 of 3.5 at 180 points.
%, which is not only excellent, but as shown in Figure 3,
American Standard IEEE, No. 275, the insulation according to this embodiment, shown by the straight line N in Figure 3, has higher heat resistance than the conventional F class insulation shown by the straight line m in Figure 3, and is better than the H class insulation. It was found that it has an insulating function. In addition, although the above examples have all been described using a solvent-based prepreg tape, it is also possible to use a solvent-free type by selecting the composition, and other hardened unfired mica sheets, You can also use flake mica, etc., and you can also use heat-resistant film or paper as a backing layer.
Of course, various modifications can be made without changing the gist. As explained above, the prepreg mica tape according to the present invention has a long shelf life at room temperature and at the same time cures at a relatively low temperature in a short time, so the electrical insulation wire theory obtained from this is economical and moreover. , has high heat resistance, strong mechanical strength, excellent electrical insulation properties, and H
This is a lightning stun wire ring suitable for use as insulation.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing Embodiment 1 of the electric disconnection line decommissioning theory of the present invention, Fig. 2 is a temperature-tan6 characteristic curve diagram thereof, and Fig. 3 is a sectional view of Embodiment 2 and the conventional F type feeding decommissioning line. FIG. 3 is a characteristic curve diagram showing a comparison of the heat-resistant life of the two. 1...mica tape, 2...4 wire ring, 1
...Initial characteristic curve, B...Characteristic curve after heating for 100 hours at 22500, m...Characteristic curve of conventional F class insulation, W...Characteristic curve of Example 2 Characteristic curve. Figure 2 Figure 1 Figure 3

Claims (1)

[Scope of Claims] 1. 0.0001 to 5% by weight of an aluminum compound as a curing catalyst and 0.0001 to 5% by weight of a hydroxyl group as a curing accelerator based on the combined maleimide compound and epoxy resin. electrical insulation, characterized in that it is made by winding a mica tape having as an adhesive a resin composition containing as an essential component a silane compound containing 0.0001 to 5% by weight of a polysiloxane compound, and curing it by heating. Line wheel. 2 The composition ratio of the maleimide compound and the epoxy resin is 5 to 95% by weight for the maleimide compound and 95 to 5% by weight for the epoxy resin.
The electrically insulating wire according to claim 1, characterized in that the amount is expressed as % by weight.