JP2608094B2 - Dipping material for condenser - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a dipping material for a capacitor. In detail, the present invention has a storage stability for a long time at a temperature near normal temperature as a first feature, and a short-time irradiation of energy rays as a second feature when dipping and sealing a capacitor, particularly a film capacitor. And a dipping material for a capacitor, which reduces dripping of the resin at the time of curing by heating at a relatively low temperature and has extremely excellent moisture resistance.

[Problems to be solved by conventional technology and invention]

Conventionally, film capacitors have been dipped and sealed with resin, but conventional dipping materials are heat-curable two-pack epoxy resins or energy-ray-curable acrylate or unsaturated polyester resins. Was used. A disadvantage common to both is lack of storage stability near room temperature. Further, heat-curable two-pack type epoxy resins require a long curing time of 2 to 10 hours to cause a resin sagging phenomenon, and energy ray-curable acrylate or unsaturated polyester resins. However, although the resin sagging was improved, each had a disadvantage that the moisture resistance was remarkably inferior to that of the two-pack type epoxy resin system.

Attempts have also been made to use a cationically polymerizable substance in combination with a photo-curing catalyst and a thermo-curing catalyst (Japanese Patent Application Laid-Open No. 58-198532), but this method is satisfactory in curability but satisfactory in moisture resistance. It didn't work.

Therefore, an object of the present invention is to provide a capacitor which is excellent in storage stability at around normal temperature, and which gives a capacitor with little resin dripping and excellent moisture resistance by short-time irradiation of energy rays and heating at relatively low temperature. To provide a dipping material.

[Means for solving the problem]

The present inventors have conducted intensive studies to achieve the above object, and as a result, completed the present invention.

That is, the capacitor dipping material of the present invention comprises, as an essential component, (I) a cationically polymerizable substance (I-
1) 70 to 100% by weight of a cationically polymerizable substance (I-1) which does not have cationic polymerizability by itself but does not contain an aromatic nucleus, or a cationically polymerizable substance containing an aromatic nucleus (II-1) An aromatic nucleus-free organic material containing no aromatic nucleus (I-2), which can be copolymerized with an aromatic nucleus-containing component, and (II) an aromatic nucleus-containing cationically polymerizable material (II-
1) 50 to 100% by weight of an organic compound containing an aromatic nucleus which does not have cationic polymerizability by itself but can be copolymerized with the cationic polymerizable substance (I-1) or the cationic polymerizable substance (II-1) Substance (II-2-1) and an organic substance containing a polymerizable non-polymerizable aromatic nucleus having a molecular weight of 800 or more (II-2-1)
One or more organic substances selected from 2) (II-
2) A component containing an aromatic nucleus consisting of 0 to 50% by weight is 1 to 40% by weight based on the total amount of (I) and (II). (III) Lewis acid is generated by irradiation with energy rays. The aromatic onium salt of a non-nucleophilic anion is used in an amount of 0.01 to 4% by weight based on the total amount of the cationically polymerizable substance (I-1) and the cationically polymerizable substance (II-1); The organic sulfonium salt of a non-nucleophilic anion which generates an acid is added to the cationic polymerizable substance (I-1) and the cationic polymerizable substance (II-1) in an amount of 0.05 to 0.05%.
-10% by weight.

Component (I) containing no aromatic nucleus used in the present invention
Cationic polymerizable substance containing no aromatic nucleus (I-
Examples of 1) include epoxides of cycloalkyl esters such as (3,4-epoxycyclohexyl) methyl-3,4-epoxycyclohexanecarboxylate and bis [(3,4-epoxy-6-methylcyclohexyl) methyl] adipate. Epoxides of cycloalkyl hydrocarbons such as vinyl hexane oxide, dicyclopentadiene dioxide, etc., and epoxides of alicyclic ethers such as bis (2,3-epoxycyclopentyl) ether, and aliphatic polyhydric alcohols. Or a polyglycidyl ether of an alkylene oxide adduct thereof,
For example, diglycidyl ether of 1,6-hexanediol, diglycidyl ether of 1,4-butanediol, triglycidyl ether of trimethylolpropane, diglycidyl ether of polypropylene glycol, diglycidyl ether of hydrogenated bisphenol A, and diglycidyl ether of polypropylene glycol An aliphatic epoxy resin such as diglycidyl ether or a monoglycidyl ether of an aliphatic higher alcohol can also be blended.

Other cationically polymerizable substances (I-
1) includes cyclic ethers, aliphatic vinyl ethers,
Examples thereof include aliphatic vinyl esters, lactones, and organosilicone cyclics.

The object of the present invention cannot be achieved unless the amount of the cationically polymerizable substance (I-1) containing an aromatic nucleus used in the present invention is 70% by weight or more of the component (I).

In the present invention, the component (I) containing no aromatic nucleus is optionally contained in an amount of 30% by weight or less of the component (I).
A cationically polymerizable substance (I-1) having no cationically polymerizable itself or an organic substance containing no aromatic nucleus capable of copolymerizing with the cationically polymerizable substance (II-1) (I-2)
Can be blended.

Examples of the organic substance that can be used as (I-2) include aliphatic polyols such as 1,4-butanediol, polypropylene glycol, and polyester polyol.

Examples of the aromatic nucleus-containing cationically polymerizable substance (II-1) in the aromatic nucleus-containing component (II) used in the present invention include, for example, a polyhydric phenol having at least one aromatic nucleus or a polyhydric phenol having the same. Polyglycidyl ether of an alkylene oxide (eg, ethylene oxide, propylene oxide, etc.) adduct can be used, and specifically, for example, diglycidyl ether of bisphenol A or F,
Polyglycidyl ether of phenol novolak or cresol novolak, diglycidyl ether of a propylene oxide adduct of bisphenol A or F, or polyglycidyl ether of halogenated polyphenol such as diglycidyl ether of tetrabromobisphenol A can be used.

Further, aromatic nucleus-containing vinyl ethers and aromatic nucleus-containing vinyl esters can also be used.

The content of the aromatic nucleus-containing cationically polymerizable substance (II-1) used in the present invention is 50% by weight or more, preferably 70% by weight or more in the component (II). The object of the invention cannot be achieved.

In the present invention, as the component (II) containing an aromatic nucleus, if desired, the component (II) does not have cationic polymerizability by itself in the range of 50% by weight or less, preferably 30% by weight or less. The cationic polymerizable substance (I-1) or the organic substance (II-2-1) containing an aromatic nucleus capable of copolymerizing with the cationic polymerizable substance (II-1) and a non-polymerizable aromatic substance having a molecular weight of 800 or more Organic substance containing group nucleus (II-2
-2) one or more organic substances (II-
2) can be blended.

Examples of the organic substance (II-2-1) containing an aromatic nucleus copolymerizable with the cationic polymerizable substance include aromatic nuclei such as alkylene oxide (eg, ethylene oxide and propylene oxide) adducts of bisphenol A. Polyols and aromatic nucleus-containing polyester resins.

Further, as the organic substance (II-2-2) containing a non-polymerizable aromatic nucleus having a molecular weight of 800 or more, for example, an aromatic nucleus-containing synthetic resin such as polycarbonate and polystyrene is preferable, and phenol / formaldehyde is more preferable. Resins and the like can also be used.

In the present invention, the content of the component (II) containing an aromatic nucleus is 1 to 40% by weight based on the total amount of the component (I) containing no aromatic nucleus and the component (II) containing an aromatic nucleus. %, Preferably 3 to 30% by weight. When the content of the component (II) containing an aromatic nucleus is out of the above range, the moisture resistance becomes insufficient.

The aromatic onium salt (III) of a non-nucleophilic anion which generates a Lewis acid upon irradiation with energy rays used in the present invention is represented by the following general formula (1).

[A] ⁺ [B] ^- (1) (. Wherein A represents a substituted onium structure comprising an energy-sensitive organic group, and B represents a non-nucleophilic anion) the non-nucleophilic anion Preferred as the ion B is a general formula MQ _m (where M is an atom selected from B, P, Sb, As, Fe, Al, Cu, Ti, Cd, Zn, Sn, Q is a halogen atom, and m is 1 to An integer of 6), for example, tetrafluoroborate (BF ₄ ), hexafluorophosphate (PF ₆ ), hexafluoroantimonate (SbF ₆ ), hexachloroantimonate (SbCl ₆ ), hexafluoroarsenate (AsF ₆ ).

Further, an anion represented by the general formula MQ _m-1 OH (where M, Q, and m are the same as above) can also be used. Still other non-nucleophilic anions include perchlorate ion (ClO ₄ ⁻ ), trifluoromethyl sulfite ion (CF ₃ SO ₃ ⁻ ), fluorosulfonic acid ion (FSO ₃ ⁻ ), toluenesulfonic acid anion, And trinitrobenzenesulfonic acid anion.

In the general formula (1), A is a cation component of an onium salt having an energy-sensitive ray structure, and is decomposed efficiently by irradiation with energy rays. Many compounds having a desirable structure have been found, and among them, aromatic halonium salts described in JP-A-50-158680, JP-A-50-151996 and the like, JP-A-50-151997, JP-A-52-30899. , 56
Nos. -55420, 56-8428, and 56-149402, and the like. VI A aromatic onium salts (aromatic sulfonium salts,
Oxosulfonium salts), and the VA group aromatic onium salts described in JP-B-50-1558698 and the like are preferred.

Further, these onium salts which can constitute the cation moiety A are described in Japanese Patent Application Laid-Open No. 55-125105.
It may be in the form of an onium salt or a tris-onium salt.

Particularly preferred for the purposes of the present invention are aromatic (oxo) sulfonium salts and aromatic iodonium salts, in particular aromatic sulfonium salts being effective.

In the present invention, the aromatic onium salt of a non-nucleophilic anion that generates a Lewis acid upon irradiation with energy rays (II
The content of I) is 0.01 to 4% by weight based on the total amount of the cationically polymerizable substance (I-1) and the cationically polymerizable substance (II-1).

Another important component of the present invention, an organic sulfonium salt (IV) of a non-nucleophilic anion which generates a Lewis acid by heat, is activated at a temperature of 150 ° C. or lower in the presence of an epoxy resin or the like. It is selected from sulfonium salts that can cause cationic polymerization. Further, although not necessarily essential as other conditions, in order to effectively achieve the object of the present invention, substantially no large ultraviolet absorption in a wavelength region of 260 mm to 400 mm, and an activity of thermal decomposition. The activation energy is preferably 17 to 20 kcal / mole or more.

Preferred as the organic sulfonium salt (IV) satisfying the above conditions are those having a special organic group selected from aliphatic sulfonium salts, and can be represented by the following general formula (2).

Here, R ₁ and R ₂ are the same or different and are substituted or unsubstituted aliphatic or aliphatic groups, and R ₁ and R ₂ may form a ring. , Nitro group,
It may contain a functional group such as a halogen group, a hydroxyl group, a carboxyl group, an ester group, an ether group, a cyano group, a carbonyl group, a sulfone group, and a thioether group.

Y is a resinous group having an electron-withdrawing functional group at the α-position or the β-position with respect to the sulfur atom, and is preferably represented by the following general formula (3) or (4).

Here, R _{3 to} R ₆ are each a group selected from a hydrogen atom and a substituted or unsubstituted aliphatic group, and R ₃ and R ₄ or R ₅ and R ₆ may be the same or different. X is an electron-withdrawing functional group.

Here, the term "electron-withdrawing functional group" refers to a substance that exerts an attraction on electrons of adjacent carbon atoms, and includes nitro, cyano, alkenyl, alkynyl, carboxyl, and carbonyl groups. Group, hydroxyl group, ester group, sulfone group, halogen group and the like.

Among them, particularly preferred are those wherein Y is an allyl group or a tertiary aliphatic group substituted with at least one aliphatic group, and which has a group represented by the following general formula (5) or (6). It is.

Wherein R ₇ to R ₁₀ are each a hydrogen atom or a substituted or unsubstituted aliphatic group, preferably an alkyl group, R ₇ ~
At least one of R ₉ must be a substituted or unsubstituted aliphatic group, preferably an alkyl group. R _{11 to} R ₁₃ are selected from a substituted or unsubstituted aliphatic group, preferably an alkyl group.

In some cases, the curability by heat may be slightly reduced, but Y may be a substituted or unsubstituted benzyl group. B has the same meaning as in the general formula (1).

Such organic sulfonium salts are relatively easily synthesized, for example, by reacting the corresponding sulfide with a highly active alkyl halide to synthesize a sulfonium salt having a halogen anion, and then HMQ _m , NaMQ _m , KMQ _m , NH ₄ MQ _m (M,
Q and m can be obtained by performing anion exchange with a reagent such as the same as described above), or in a good yield by directly reacting a sulfide with a mail wine reagent such as triethyloxonium tetrafluoroborate. It is also possible to synthesize them.

When a tertiary aliphatic group is reacted with a sulfide, the reaction can be carried out under acidic conditions using the corresponding alcohol as a starting material to obtain a sulfonium salt.

In the present invention, the content of the organic sulfonium salt (IV) of a non-nucleophilic anion which generates a Lewis acid by heat is determined by the cationic polymerizable substance (I-1) and the cationic polymerizable substance (II).
It is in the range of 0.05 to 10% by weight based on the total amount of -1).

As long as the effects of the present invention are not impaired, various paint additives such as coloring agents such as pigments and dyes, sensitizers, defoamers, leveling resins, thickeners, flame retardants, silica, talc, and the like can be used. , Glass powder, asbestos powder, mica powder, and other fillers can be used in appropriate amounts.

Suitable energy rays that can be applied to the dipping material of the present invention may be any energy rays as long as they have energy that induces the decomposition of the photosensitive aromatic onium salt (III). Obtained from xenon lamps, germicidal lamps, laser light, sun lamps, etc.
Electromagnetic energy having a wavelength of 2,000 to 7,000 mm and high energy rays such as electron beams, X-rays, and radiations are used.

Exposure to energy rays varies depending on the type and strength of the energy ray and the type, amount, thickness and the like of the compound in the dipping material of the present invention, but usually about 1 second to 2 minutes is sufficient.

The dipping material of the present invention can be cured more effectively and effectively by using heating, preferably after irradiation with energy rays. The temperature at which the cured product is obtained by using energy rays and then completely cured by heating is kept in the range of 100 to 200 ° C, in the range of several seconds to several hours, depending on the type of capacitor. Is preferred. For example, when the dipping material of the present invention is applied to a polypropylene or polyester film capacitor, heating at 100 to 110 ° C. for 0.5 to 2 hours is preferable.

〔The invention's effect〕

The effect of the present invention is that it has a long-term storage stability at around normal temperature, and can be used as a dipping material for capacitors. Resin dripping can be reduced as compared with the case of using epoxy resin, and the use of a cationically polymerizable component containing no aromatic nucleus and a cationically polymerizable component containing an aromatic nucleus makes it extremely resistant to moisture. I got the dipping material.

〔Example〕

Hereinafter, the present invention will be specifically described based on examples,
The present invention is not limited to these examples.

 The parts in the examples are on a weight basis.

Examples-1 to 7 Using the method described in JP-A-55-125104,
Give [4- (diphenylsulfonio) phenyl] sulfide bis chloride, aqueous solution KAsF _6, or by performing NaSbF ₆ and salt exchange, the corresponding non-nucleophilic photosensitive sulfonium salt having an anion (A・ 2AsF ₆ ,
A.2SbF ₆ ) was obtained (hereinafter, the cation component, ie, bis- [4- (diphenylsulfonio) phenyl] sulfide is represented as A).

On the other hand, prenyl tetramethylene sulfonium hexafluoroantimonate and crotyl tetramethylene sulfonium hexafluoroantimonate were obtained as heat-sensitive organic sulfonium salts using the method described in JP-A-58-37004. Thermal catalysts B and C).

Using these photosensitive sulfonium salts and heat-sensitive sulfonium salts, dipping materials for capacitors having the compositions shown in Table 1 were obtained.

Comparative Example-1 Bisphenol A type epoxy acrylate (viscosity 1.5
100 parts of (100,000 cps / 50 ° C), 200 parts of Aronix M-101 (manufactured by Toa Gosei), 10 parts of benzophenone, 5.0 parts of dicumyl peroxide, and 2 parts of Aerosil R-972 are mixed to prepare a dipping material for capacitors. Obtained.

Comparative Example-2 Adeka Resin EP-4100E 80 parts, Adekaglycylol ED
-503 20 parts, Adeka Hardener EH-700 (methyltetrahydrophthalic anhydride) 85 parts, Adeka Hardener EHC-30
2 parts of [tris (dimethylaminomethyl) phenol] and 2 parts of AERYL®R-972 were mixed to obtain a dipping material for a capacitor.

Comparative Examples -3 to 5 Dipping materials for capacitors were obtained in the same manner as in Examples -1 to 7 with the composition shown in Table 1.

The dipping materials for capacitors obtained in Examples 1 to 7 and Comparative Examples 1 to 5 were impregnated and cured using a PET film capacitor having a capacity of 100 nF to obtain a resin-sealed film capacitor.

 The conditions for the impregnation hardening were as follows.

Impregnation conditions: The sample was immersed in a vacuum of 20 mmHg for 5 minutes.

Curing conditions: 80 W / cm for Examples-1 to 7 and Comparative Examples 3 to 5
UV irradiation at a distance of 20 cm from the lamp for 5 seconds, followed by heat curing for 1 hour in a 110 ° C. curing furnace. For Comparative Example-1, the UV irradiation time was
The heat curing was performed at 110 ° C. for 2 hours for 15 seconds.
With respect to Comparative Example-2, heating was performed for 4 hours in a curing oven at 110 ° C without irradiation with ultraviolet rays.

Thereafter, the initial capacity C _{0 of} the above-mentioned resin-encapsulated film capacitor and the capacity C after performing a humidity resistance test at 85 ° C. and a relative humidity of 95% for 120 hours were measured, and the quantitative change rate ΔC was calculated by the following equation. I asked.

The capacity was measured using a YHP LCR meter and the frequency
Performed at 1 KHz.

The results are shown in Table 1. The results using the dipping materials of Examples -1 to 7 were all excellent in moisture resistance as compared with the comparative examples, without resin dripping unlike Comparative Example 2, and Comparative Example 2 The same level of moisture resistance was obtained.

Also, in the storage stability test, good results were obtained as compared with Comparative Examples 1-2.

* 1: Alicyclic epoxide manufactured by Union Carbide, epoxy equivalent 131-143.

* 2: Alicyclic low viscosity epoxide manufactured by Union Carbide, epoxy equivalent 120-130.

* 3: Asahi Denka Kogyo's aliphatic glycidyl ether, epoxy equivalent 150-180.

* 4: Bisphenol A type epoxide manufactured by Asahi Denka Kogyo, epoxy equivalent 185-195.

* 5: Nippon Kayaku phenol novolak epoxide,
Epoxy equivalent 175-195.

* 6: Asahi Denka Kogyo's aromatic nucleus-containing polyol, hydroxyl equivalent
300-320 mgKOH / g.

* 7: Polycarbonate manufactured by Mitsubishi Gas Chemical, melting point 230 ° C, molecular weight 23000.

* 8: Modified polystyrene manufactured by Rika Hercules, softening point 75
° C, molecular weight 917.

* 9: Viscosity 15,000 cps / 50 ° C.

* 10: Acrylic acid monoester manufactured by Toa Gosei Chemical.

* 11: Fine powder silica made by Nippon Aerosil.

* 12: Methyltetrahydrophthalic anhydride manufactured by Asahi Denka Kogyo.

* 13: Tris (dimethylaminomethyl) phenol manufactured by Asahi Denka Kogyo.

* 14: The time it takes for the viscosity (/ 25 ° C) to double after storing at 40 ° C.

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C08G 59/68 NKM C08G 59/68 NKM 63/02 NLY 63/02 NLY 65/00 NQC 65/00 NQC 77/06 NUB 77/06 NUB 77/08 NUD 77/08 NUD

Claims (1)

(57) [Claims] (1) As an essential component, (I) a cationically polymerizable substance containing no aromatic nucleus (I-
1) 70 to 100% by weight of a cationically polymerizable substance (I-1) which does not have cationic polymerizability by itself but does not contain an aromatic nucleus, or a cationically polymerizable substance containing an aromatic nucleus (II-1) An aromatic nucleus-free organic substance (I-2) which can be copolymerized with an aromatic nucleus-free component consisting of 0 to 30% by weight; (II) an aromatic nucleus-containing cationic polymerizable substance (II-
1) 50 to 100% by weight of an organic material containing no cationically polymerizable substance by itself but containing an aromatic nucleus capable of copolymerizing with the cationically polymerizable substance (I-1) or the cationically polymerizable substance (II-1) Substance (II-2-1) and an organic substance containing a polymerizable non-polymerizable aromatic nucleus having a molecular weight of 800 or more (II-2-1)
One or more organic substances selected from 2) (II-
2) 0 to 50% by weight of a component containing an aromatic nucleus, 1 to 40% by weight based on the total amount of (I) and (II); (III) Lewis acid is generated by irradiation with energy rays The aromatic onium salt of a non-nucleophilic anion is used in an amount of 0.01 to 4% by weight based on the total amount of the cationically polymerizable substance (I-1) and the cationically polymerizable substance (II-1), and (IV) heat-induced Lewis The organic sulfonium salt of a non-nucleophilic anion that generates an acid is added to the cationic polymerizable substance (I-1) and the cationic polymerizable substance (II-1) in an amount of 0.05 to 0.05%.
A dipping material for a capacitor, characterized by containing about 10% by weight.