JPS6136316A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide the titled composition composed of an epoxy resin, a curing agent and an additive consisting of an oxidized wax (derivative) and an organotin compound, having excellent moisture resistance and rustproofing property, and useful for the sealing of electronic circuit parts, etc. CONSTITUTION:The objective composition can be prepared by compounding (A) an epoxy resin with (B) a curing agent and (C) an additive consisting of (i) oxidized wax and/or oxidized wax derivative and (ii) an organotin compound. Preferably, the component A is phenol novolac or cresol novolac resin, the component B is a phenolic resin, the component (i) is paraffin wax, etc., and the component (ii) is an alkyltin compound, and the amounts of the components (i) and (ii) are 0.1-10pts.(wt.) and 0.01-5pts. per 100pts. of the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an epoxy resin composition used as a sealing resin for semiconductor devices and other electronic circuit components.

[Conventional technology]

Acid anhydrides have traditionally been used as sealing materials for electronic components such as transistors, diodes, ICs, and LSIs.

Epoxy resin compositions using amines, phenolic resins, etc. as curing agents are widely used.

This is because epoxy resins are superior to other thermosetting and thermoplastic resin materials in terms of mechanical properties, gas properties, thermal properties, moldability, etc. This is because it is superior to hermetic seal systems using metal or ceramic materials in terms of productivity and economy.

However, in recent years, with the development of the electronics field, epoxy resin compositions have come to be used in a wide variety of applications2.For example, their use outdoors in extremely cold, hot and humid regions, as typified by automobiles, is also increasing. .

Furthermore, as typified by 256-bit VLSI, electronic circuits are rapidly becoming denser and thinner. As a result, cases have frequently been reported in which electronic components suffer catastrophic failures due to the effects of external heat and moisture, especially during practical operation.

Many of these defects are said to be due to the effects of ionic impurities contained in the epoxy resin composition and moisture that has entered from the outside world.

That is, since the molded body of the epoxy resin composition itself has moisture permeability, moisture that has entered the molded body permeates to the surface of the resin-sealed electronic component, causing corrosion and deterioration of metal electrodes such as aluminum. Also.

Along with moisture permeation, moisture also infiltrates from the lead frame interface.
Corrodes as well. Furthermore, water dissolves organic acids and ionic impurities such as Na'' and C4- contained in the epoxy resin, and carries them to the surface of electronic components to form local batteries, further promoting corrosion. These ionic impurities contained in epoxy resin are derived from the synthetic raw material epichlorohydrin and the subsequent synthesis process, so it is virtually impossible to completely remove them. However, epichlorohydrin causes a side reaction and remains as hydrolyzable chlorine in the epoxy resin.These hydrolyzable chlorines are ionized by the catalytic action of heat and other factors.

Corrodes aluminum electrodes, etc.

Therefore, various proposals have been made to deal with these problems.

For example, reduction of ionic impurities in epoxy resin (JP-A-58-122915, JP-A-58-13411)
No. 2], selection of internal mold release agent (Japanese Patent Application Laid-Open No. 1520-1983
No. 47), addition of additives to capture ionic impurities in epoxy resin compositions (Japanese Patent Application Laid-Open No. 1744-1983)
Publication No. 35.

Japanese Unexamined Patent Publication No. 58-176237) has been carried out, but no particularly significant effect has been obtained.

[Problem that the invention seeks to solve]

As a result of various studies regarding the above-mentioned problems, the present inventors have formulated an additive that suppresses corrosion and has low compatibility with the epoxy resin into an epoxy resin composition, and has developed an additive that suppresses the blooming (seepage) of these additives during molding. ) phenomenon to form a film on the surface of electronic components to suppress corrosion of aluminum electrodes caused by ionic impurities, moisture, etc., in other words, to improve moisture resistance and rust prevention. .

[Means for solving problems]

The present invention is an epoxy resin composition characterized by comprising an epoxy resin, a curing agent, one or both of an oxidized wax or a fermented wax derivative, and an additive comprising an organic tin compound.

The epoxy resin used in the present invention has at least two or more 1 boxy groups in the molecule, and is not particularly limited to a structure with a molecular weight of 1 molecule.For example, glycidyl ether-based epoxy resin, phenol Novolac epoxy resins, Talezol novolac epoxy resins, alicyclic epoxy resins, glycidyl ester epoxy resins, linear aliphatic epoxy resins, halogenated epoxy resins, etc., as long as they are commonly used as molding materials. However, these epoxy resins may be used alone or in a mixture of two or more.

In this case, it is desirable to have less ionic impurities such as sodium and chlorine, and less hydrolyzable chlorine. Furthermore, among the above-mentioned epoxy resins, phenol novolac epoxy resins and cresol novolac epoxy resins are preferred from the viewpoint of electrical properties, heat resistance, etc., and excellent properties can be obtained. These epoxy resins undergo a curing reaction and are solidified by the curing agent shown below.

Next, as a curing agent, 7-talic anhydride, cohelic anhydride,
Acid anhydrides such as methylnadic anhydride, aromatic amines such as metaphenylene diamine, diaminodiphenylsulfone, and aromatic amine adducts, aliphatic or alicyclic amines such as polymethylene diamine and menthanediamine, phenolic resins, cresol resins, etc. Examples include synthetic resin initial condensates, but are not particularly limited. These curing agents may be used alone or in a mixture of two or more. However, among the above curing agents, the electrical properties.

In view of heat resistance, etc., synthetic resin initial condensates such as 7-enol resin and cresol resin are preferred.

In the present invention, the compounding ratio of the Nigeki resin and the curing agent is such that the chemical equivalent ratio between the number of functional groups in the curing agent and the number of epoxy groups in the epoxy resin is within the range of 0.5 to 1.5. It is preferable to blend them in terms of curing properties such as storage stability, curing speed, and thermal and mechanical properties after curing. Furthermore, excellent curing properties can be obtained when the chemical equivalent ratio is within the range of 0.8 to 1.2.

Further, in the second invention, when the above curing agent is used, a curing accelerator may be used to accelerate the curing speed.

The curing accelerator is not particularly limited, but may be
For example, imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2,4-dimethylimidazole, amines such as triethylamine, diethylaminopropylamine, benzyldimethylamine, N-amine ethylpiperazine, triethylamine, etc. Examples include complex compounds with boron (BF).Also.

These curing accelerators may be used alone or in a mixture of two or more, and the amount added is 0.05 to 5 % based on the resin.
A range of parts by weight is desirable.

A part of the additive consisting of one or both of the oxidized wax or the oxidized wax derivative and the organotin compound does not react with the epoxy resin and the curing agent, and does not react with the epoxy resin and the curing agent during resin sealing of electrical parts with the epoxy resin composition. Or, after that, it seeps out from inside the resin. Furthermore, this additive reaches the surface of the sealed electrical component and forms a rust-preventing film. The anticorrosive film has excellent moisture resistance and can prevent the infiltration of ionic impurities and protect electrical components.

The above oxidized waxes are oxidized paraffin wax, microcrystal wax, petrolatum, etc. separated and purified from 9 petroleum oils, and one or two of these are used.
It is better to use more than just seeds. Further, the oxidized wax derivative is obtained by adding reaction operations such as saponification and esterification dipolymerization to the above-mentioned oxidized wax to improve the antirust effect.

For example, metal salts of oxidized waxes such as barium salts, lead salts, magnesium salts, calcium salts, and aluminum salts, esters of oxidized waxes such as alkyl esters such as methyl, ethyl, and oleyl, sulfonated products of oxidized waxes, and sulfones of oxidized waxes. Acid alkyl esters include polyoxyethylene esters of oxidized wax, etc.
It is preferable to use IFlt or two or more of these. In addition, there are no particular restrictions on the purification method, degree of purification, acid value, saponification value, esterification value, iodine value, melting point, etc. for oxidized wax and oxidized wax derivatives.
Regarding the acid value, preferably one having an acid value of 30 or less is preferable. Furthermore, oxidized waxes or oxidized wax derivatives diluted with mineral oil or the like can also be used.

In the present invention, one or both of the oxidized wax derivatives are used as the oxidized wax layer.

The blending amount of one or both of the oxidized wax and oxidized wax derivative is preferably 0.1 to 10 parts by weight per 100 parts by weight of Nigekishi. When the blending amount is less than 0.1 part by weight, the moisture resistance of the present invention
The rust prevention effect is demonstrated.

On the other hand, if the amount exceeds 10 parts by weight, although the addition provides a moisture-resistant effect, other properties such as heat resistance and moldability may deteriorate.

Further, although there is no particular restriction on the above-mentioned organic tin compound, it is preferably a stable compound with good hydrophilicity.

For example, alkyltin compounds, alkyltin mercaptide compounds, alkyltin sulfide compounds.

Alkyltin unsubstituted carboxylic acid salt compounds, alkyltin maleic acid compounds, alkyltin heptamalic acid compounds,
Alkyltin substituted carboxylate compounds, alkyltin acid compounds, alkyltin inorganic acid chlorides, bis(alkyltin) oxide compounds.

Organotin stabilizers added to polyvinyl chloride such as alkylhydroxytin compounds, alkylalkoxytin compounds, aryltin compounds, Fe/lardtin compounds, tin-nuclear carbonyl compounds, tin side-chain carboxylate compounds, tin aliphatic carboxylates, etc. Agents, etc. are thrown in the fist.

More specifically, tetrabutyltin, dibutyltin dilauryl mercaptide, butyltin trisdodecyl mercaptide, dimethyltin sulfide, monooctyltin sulfide, tributyltin laurate, and tributyltin oleate.

Dibutyltin dilaurate, dibutyltin distearate, dibutyltin laurate maleate.

Dioctyltin laurate maleate, tributyltin acetate, trimethyltin maleate.

Examples include tributyltin maleate, tributyltin gluconate, dibutyltin oxide, bitributyltin oxide, tetraphenyltin, tributyltin butylferrate, tributyltin benzoate, triphenyltin benzoate, triphenyltin terephthalate, and tributyltin cinnamate. In the present invention, it is preferable to use one or more of these organotin compounds.

The amount of the organic tin compound compounded is 1:1 of the epoxy resin.
It is desirable that the amount is 0.01 to 5 parts by weight per 900 parts by weight. If the amount is less than 0.011 parts by weight, the moisture resistance and rust prevention effects of the present invention will be difficult to exhibit.

On the other hand, if the amount exceeds 5 parts by weight, although the addition provides an anti-immersion effect, there is a risk that heat resistance and moldability may deteriorate.

The present invention may be composed only of the above-mentioned components (a) epoxy resin, (b) curing agent, (C) additives consisting of the above-mentioned organic tin compound, etc., but it is also possible to further incorporate all of the inorganic photonic agents. 9 dimensional stability and thermal properties than K.

An epoxy resin composition with improved workability etc. can be obtained.

Examples of inorganic photonic agents include zirconia, alumina,
Talc, clay, magnesia, fused silica, crystalline silica, calcium silicate, calcium carbonate, barium sulfate,
Examples include glass fiber and milled fiber, among which fused silica.

Crystalline silica is most preferred. The blending amount of these inorganic photonic agents is 150 to 45 parts by weight per 100 parts by weight of the epoxy resin.
A range of 0 parts by weight is desirable.

In addition, the epoxy resin composition according to the present invention may optionally be used with a mold release agent such as natural waxes, synthetic waxes, metal salts of linear fatty acids, acid amides, esters, or mixtures thereof, and chlorinated NONORAFUIN, brominated bisphenol A type epoxy resin, brominated phenol novolac type epoxy resin.

Antiflammants such as bromotoluene, hexabromobenzene, antimony E oxide, and silane coupling agents.

A surface treatment agent such as a ditan coupling agent, a coloring agent such as carbon black, etc. may be appropriately added and blended.

Using the epoxy resin composition according to the present invention as a molding material
In the case of W@, the general method is to thoroughly mix all of the above raw materials with a mixer such as a Henschel mixer, then melt-knead with a kneader such as a hot roll machine or kneader, and then cool and grind. A molding material of an epoxy resin composition can be obtained in a well-formed manner.

〔Effect of the invention〕

According to the present invention, it is possible to provide an epoxy resin composition having excellent moisture resistance, rust prevention, and adhesiveness.

In the present invention, such an effect can be obtained because the epoxy resin composition is mixed with the epoxy resin, and the additive consisting of one or both of the oxidized waxes or the oxidized wax derivatives and the organic tin compound is used to convert the epoxy resin composition into a resin sealant. This is thought to be due to the fact that when used as a coating material, it acts between the composition and the object to be coated and prevents external moisture and ionic impurities from penetrating into the surface of the object to be coated. It will be done.

As described above, the resin composition of the present invention prevents moisture and ionic impurities from entering the interface with the object to be coated, so it has excellent moisture resistance, rust prevention, and adhesiveness.

Moreover, since the epoxy resin composition of the present invention has the above-mentioned effects, it can be used in addition to the resin for sealing W1 electrical products.

It can also be used in paints, adhesives, etc.

Next, when the resin composition of the present invention is used as a sealant for electrical parts, the above-mentioned additive will form a rust-preventing film at the interface between the surface of the electrical part and the epoxy resin during or after sealing with the resin. It is thought to form a As a result, moisture from the outside and ionic impurities in the epoxy resin are blocked from penetrating into the surface of the electronic components, thereby preventing functional deterioration such as low F of insulation or increased leakage current of the electrical components. As a result, it is possible to extend the life of electrical parts.

In addition, since the epoxy beak composition contains an additive consisting of one or both of oxidized wax or oxidized wax derivatives and an organic tin compound as a rust-preventing film-forming component, electrical parts There is no need to apply a rust preventive film to the surface.

〔Example〕

Next, the present invention will be explained in detail.

50 parts by weight of orthocresol novolak epoxy resin fjrioo as an epoxy resin and 50 parts by weight of phenol novolak resin' as a curing agent.

Oxidized paraffin wax with acid value 21 M19KOH/9 as oxidized wax or oxidized wax methyl ester with [j 10 jlf KOH/7 as oxidized wax derivative, petrolatum oxide calcium salt with acid value 4jvKOH/7 and tetra as organotin compound Butyltin or dioctyltin distearate was mixed in the proportions shown in Table 1 (all amounts are in parts by weight). Furthermore, 3 parts by weight of 2-phenylimidazole as a curing accelerator, 350 parts by weight of fused silica as an inorganic filler, 2 parts by weight of epoxy silane as a surface treatment agent, 2 parts by weight of carnauba wax as a molding agent were added. and mixed. Next, this material was melt-kneaded using a roll machine for 5 minutes at a temperature of 80 to 90°C, immediately cooled to solidify, and pulverized. after that.

This pulverized product is molded into a tablet shape, and the method according to the present invention is
All types of epoxy resin compositions (samples &1 to 4 in Table 1) were prepared.

For comparison, as shown in Table 1, only the oxidized paraffin wax or tetrabutyltin was used as an additive, and no additives were used, but the ingredients were the same as above, and the amounts were 9. Three comparative epoxy resin compositions (Samples ACI-C3 in Table 1) were prepared.

Using the above seven types of epoxy resin compositions, for a model element having aluminum wiring and electrodes.

Sealing was carried out using a transfer molding machine at 175°C for 3 minutes, and then post-cured by heating at 165°C for 8 hours to complete resin sealing. In order to test the performance of these sealed samples, a pressure puller test was performed on these samples in saturated steam at 121'C* 2 atm with a bias of 12V applied. The average lifespan of each sample was measured to evaluate its moisture resistance.

The results are shown in Table 2. What is the average lifespan here?

It refers to the average time (hr, 50% average for multiple samples) until the aluminum wiring or electrode becomes corroded and loses its WL air groove conductivity.

As is clear from Table 2, when the epoxy resin composition according to the present invention is used, the average life is improved by 9M compared to the comparative composition even under high temperature and high humidity. 9 The resin composition of the present invention is found to be extremely useful as a resin for sealing electrical parts.

Kyo Tsune 7.・ /″ Table 1 Table 2

Claims (4)

[Claims] (1) An epoxy resin composition comprising an epoxy resin, a curing agent, one or both of an oxidized wax or an oxidized wax derivative, and an additive comprising an organic tin compound. (2) Epoxy resins include glycidyl ether epoxy resins, phenol novolak epoxy resins, cresol novolak epoxy resins, alicyclic epoxy resins, glycidyl ester epoxy resins, linear aliphatic epoxy resins, and halogenated epoxy resins. The epoxy resin composition according to claim (1), which is at least one of: (3) One or both of the oxidized wax and the oxidized wax derivative is 0.1 parts by weight per 100 parts by weight of the epoxy resin.
The epoxy resin composition according to claim (1), wherein the epoxy resin composition contains 10 parts by weight. (4) The epoxy resin composition according to claim (1), wherein the organic tin compound is blended in an amount of 0.01 to 5 parts by weight per 100 parts by weight of the epoxy resin.