JPS6123622A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:The titled composition excellent in moisture resistance, rust inhibition and adhesion and useful as a sealing resin for electrical parts, prepared by mixing an epoxy resin with a curing agent and a specified additive. CONSTITUTION:An epoxy resin composition prepared by mixing an epoxy resin (e.g., glycidyl ether or phenol novolak epoxy resin) with an additive comprising a curing agent (e.g., phthalic anhydride), a dithiophosphoric acid (derivative), e.g., diisopropyl dithiophosphate (or its zinc salt) and an organotitanium compound (e.g., tetraisopropyl titanate). The incorporation of said additive makes it possible to prevent moisture or ionic impurities from penetrating into the interface between the resin composition and the substrate, so that this resin composition can show excellent moisture resistance, rust inhibition and adhesion. Therefore, it can be used as a sealing resin for electrical parts or used for paints, adhesives, etc.

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, electrical properties, thermal properties, moldability, etc.), and This is because it is superior to hermetic seal systems for metal and 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 applications.1 For example, there is an increasing tendency for epoxy resin compositions to be used outdoors in extremely cold or hot and humid regions, as typified by automobiles. be.

Furthermore, as typified by the 256-bit VL8I, electronic circuits are rapidly becoming denser and finer. 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.

In other words, since the molded body of the epoxy resin composition itself has moisture permeability, water 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 CI- contained in the epoxy resin and carries them to the surface of electronic components to form local batteries, thereby further promoting corrosion. These ionic impurities contained in the epoxy resin are derived from the synthetic raw material epichloro-μ-hydrin and the subsequent alkaline washing process, so it is virtually impossible to completely remove them. In addition, to a small extent, epichloroμ hydrin undergoes a side reaction, becoming hydrolyzable chlorine and remaining in the epoxy resin, and these hydrolyzable chlorines are catalyzed by heat and other factors.

It ionizes and 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-58-122915,
134112) Selection of internal mold release agent (JP-A-58-
152047).

Addition of additives to trap ionic impurities in epoxy resin compositions (Japanese Unexamined Patent Publication No. 174455/1983,
Although various attempts have been made (Japanese Patent Application Laid-Open No. 58-1'76237), no particularly significant effect has been obtained.

[Problems to be solved by the invention]

As a result of various studies regarding the above problems and levers, the present inventors have formulated an additive that suppresses corrosion and has low compatibility with the epoxy resin in the epoxy resin composition, and has developed a method to prevent corrosion during molding.
By utilizing these blooming (staining) phenomena to form a film on the surface of electronic components, corrosion of aluminum electrodes etc. due to ionic impurities, moisture, etc. can be suppressed, in other words, moisture resistance.

The idea was to improve rust prevention.

[Means for solving problems]

The epoxy resin composition of the present invention is characterized by comprising an epoxy resin, a curing agent, and an additive comprising one or both of dithiophosphoric acid or a dithiophosphoric acid derivative and an organic titanium compound. ``The epoxy resin used in the present invention may have at least two or more epoxy groups in 9 molecules, and is not particularly limited to a molecular weight of 9 molecules. For example, glycidyl ether thread epoxy resin, phenol novolac epoxy resin, cresol novohook evoquine resin.

Any resin commonly used as a molding material may be used, such as alicyclic epoxy resin, glycidium ether-based epoxy resin, linear aliphatic epoxy resin, or halogenated epoxy resin. However.

These epoxy resins may be used alone or in a mixture of two or more. Among the above epoxy resins, those containing less ionic impurities such as chlorine and chlorine, and those containing less hydrolyzable chlorine are preferable, and from the viewpoint of electrical properties and heat resistance, pheno-μ novolac epoxy resins, cresol novolac epoxy resins, etc. Resins are preferred and provide the best properties. These epoxy resins undergo a curing reaction and are solidified by the following curing agent.

Next, as curing agents, phthalic anhydride, succinic anhydride,
Acid anhydrides such as methylnadic anhydride; aliphatic and cycloaliphatic amines such as methamethylene diamine and menthanediamine;
Examples include initial condensates of synthetic resins such as phenol resins and creso p resins.

There are no particular restrictions. The above-mentioned curing agents may be used alone or in a mixture of two or more. However, among the above-mentioned curing agents, synthetic resin initial condensates such as phenol resins and cresol resins are preferred from the viewpoint of electrical properties, heat resistance, and the like.

In the present invention, the compounding ratio of the epoxy 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.

Furthermore, in the present 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 examples include 2-methylimidazole, 2-phenylimidazo-
Imidazo-μ such as 1,,2,4-dimethylimidazo-p
Examples include amines such as triethylamine, diethylaminopropylamine, benzyldimethylamine, and N-aminoethylhiberazine, and complex compounds of triethylamine and boron trifluoride (BFi). Further, these curing accelerators may be used alone or in a mixture of two or more. However, the blending ratio of this curing accelerator may generally be within the range of 0.05 to 5M parts per 100 parts by weight of the epoxy resin.

Some of the additives comprising one or both of dithiophosphoric acid or dithiophosphoric acid derivatives and an organic titanium compound according to the present invention do not react with the epoxy resin and the curing agent, and therefore do not react with the epoxy resin composition during resin sealing of electrical components. Or, after that, it seeps out from inside the resin. The components of this additive reach the surface of the sealed electrical components and prevent ##! Forms a film. The anti-rust film has excellent moisture resistance and can protect electrical components by preventing infiltration of ionic impurities.

The above-mentioned dithiophosphoric acid is generally represented by the following chemical formula (A), and examples include diisobutymu dithiophosphoric acid, diphenyldithiophosphoric acid, diisopropyldithiophosphoric acid, cytodecanebenzenedithiophosphoric acid, and one of these.
It is preferable to use one species or two or more species.

(fc, above formula CA), l R'' and u 2
represents an alkyl group, ary/I/ group, alkeni/V group having 1 to 18 carbon atoms, and may be the same or different;
0 represents oxygen, P represents phosphorus, S represents sulfur, and ■ represents hydrogen.

) The above dithiophosphoric acid derivatives are generally represented by the following chemical formula (B), and include zinc diisopropyldithiophosphate, zinc di-n-butyldithiophosphate, and zinc dithiophosphate.
Zinc S-butyldithiophosphate, zinc diisobutyldithiophosphate, zinc diisoamyldithiophosphate, zinc diamipdithiophosphate.

Zinc di4-methylpentyldithiophosphate, zinc di2-ethylhexyldithiophosphate, zinc diisodecyldithiophosphate, zinc diphenyldithiophosphate.

Examples include metal salts of dithiophosphate such as zinc cytodecane benzenedithiophosphate and molybdenum diisopropyldithiophosphate, and ammonium dithiophosphate salts such as ammonium diisopropyldithiophosphate and ammonium di2-ethylhexy I dithiophosphate, and one or two of these. It is better to use more than just seeds. In the present invention, one or both of dithiophosphoric acid or dithiophosphoric acid derivatives are used.

(However, in the above formula CB, n and i4 represent an alkyl group, an aryl group, and an kenyl group having 1 to 18 carbon atoms, and may be the same or different.

M is zinc (z”)
), Iron ('') +=, KeJv (Ni), Tin (S
n), metal elements such as silver (Ag), lead (Pb), or ammonium salts.

m and n represent integers, O represents oxygen, P represents phosphorus, and S represents sulfur. ) The blending amount of one or both of the dithiophosphoric acid and the dithiophosphoric acid derivative is preferably 0.05 to 10 parts by weight per 100 parts by weight of the epoxy resin. 0
．． If it is less than 0.05 parts by weight.

On the other hand, the moisture resistance and rust prevention effects of the present invention are difficult to exhibit.

When the amount exceeds 10 parts by weight, the effect of addition is improved, but other properties such as heat resistance are improved.

There is a risk of reducing adhesive properties.

The organic titanium compound, which is another important component of the additive in the present invention, is not particularly limited, but preferably a compound with good water repellency.

Generally, titanium alkoxides, monomers and polymers of chelate compounds, coordination compounds, etc. can be mentioned. Specifically, tetraisopropyl titanate.

Tetoptyl titanate, tetra-2-ethylhexyl titanate, tetrastearyl titanate.

Isopropyl tristearyl titanate, tributyl stearyl titanate, butyl titanate dimer, polytripropyl titanate, polybutyl titanate, polytrigyl stearyl titanate, titanium acetylacetonate, titanium ethyl acetoacetate, titanium octylene glycolate, dihydroxyvinu(lactate) Titanium.

Tetraoctylene glycol titanium, dipropoxytitanium bis(lactate), polytitanium acetylacetonate, polyhydroxytitanium stearate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate , tetraoctylbis(ditridecylphosphite) titanate, tetra(2,2-diallyloxymethyIL/-1-buty/L/)bis(di-tridecylphosphite)titanate, bis(dioctylpyrophosphate)oxia Sade titanate.

Examples include bis(dioctylpyrophosphate) ethylene nathanate, and it is preferable to use one or more of these.The amount of the organic titanium compound compounded is 100 parts by weight of the epoxy resin. Te 0.
It is desirable to set it as 01-5 parts by weight. If the amount is less than 0.01 part 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 there is a moisture resistance effect due to the addition of IIA, other properties 1 such as heat resistance and moldability may be deteriorated.

The present invention may be composed only of additives such as the above-mentioned components (a) Epoquine resin, (b) curing agent, (e) organic titanium compound, etc., but an inorganic photonic agent may also be added. By doing so, it is possible to obtain an epoxy resin composition that has several times the dimensional stability, thermal properties, and productivity.

Examples of inorganic photonic agents include zirconia, alumina,
Examples include talc, clay, magnesia, crystalline silica, calcium silicate, calcium ash, barium sulfate, glass fiber, and milled fiber. Among these is fused silica.

Crystalline silica is most preferred.

In addition, the epoxy resin composition according to the present invention may optionally contain 1 natural waxes, 2 synthetic waxes, metal salts of linear fatty acids, acid amides, esters, or mixtures thereof, etc., # type agents, chlorinated Paraffin, brominated bispheno-7Ai epoxy resin, brominated phenol novolak type epoxy resin.

Bromotoluene, hexabromobenzene, trioxide.

Flame retardants such as antimony, silane coupling agents.

A surface treatment agent such as a titanium coupling agent, a colorant such as carbon black, and gold may be appropriately added and blended.

A general method for manufacturing the epoxy resin composition according to the present invention is to thoroughly mix the above raw material components using a mixer such as a Henssier/L' mixer.

There is a method of melting, kneading, cooling, and pulverizing in a mixing machine such as a heat roller machine or a kneader.

〔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 additive consisting of one or both of dithiophosphoric acid or dithiophosphoric acid derivatives mixed with the epoxy resin and an organic titanium compound is used in the epoxy resin composition as a resin sealant, etc. It is thought that this is because when the composition is coated, it is present between the composition and the object to be coated, and exerts the effect of preventing external moisture and ionic impurities from penetrating into the surface of the object to be coated. in this way.

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 moisture resistance, rust prevention,
It has excellent adhesive properties.

- Also, since the epoxy resin composition of the present invention has the above-mentioned effects, it can be used not only as a resin for sealing electrical parts.

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

Second, when the resin composition of the present invention is used as a sealant for electrical parts, the additive forms a rust-preventive film at the interface between the surface of the electrical parts and the epoxy resin during or after the resin sealing. It is thought that it forms. As a result, moisture from the outside and ionic impurities in the epoxy resin are blocked from penetrating into the surface of the electronic component, thereby preventing a decrease in the insulation properties of the electrical component or a decrease in functionality such as an increase in leakage current. This makes it possible to extend the life of electrical components.

Further, since the above-mentioned additive as an anti-M film forming component is contained in the epoxy resin composition, there is no need for a step of applying a rust preventive film to the surface of the electrical component.

〔Example〕

Hereinafter, the present invention will be explained in detail.

100 parts by weight of orthocresol nopolasocuevoquin resin as an epoxy resin, 50 parts by weight of phenol novolac resin as a hardening agent, zinc di-n-butyldithiophosphate and zinc cytodecampene dithiophosphate as dithiophosphoric acid derivatives. , di-2-ethylhexyl ammonium rethiophosphate, and inpropyl tristearyl titanate and tetraoctyl bis(cytridecyl phosphite) titanate as adsorbed titanium compounds are shown in Table 1 (all amounts shown are in parts by weight). ) (mixed on an IJ stand, added 2-phenylimidazo/l/3 as a curing accelerator, 550 parts by weight of fused silica as an inorganic filler, 1 part by weight as a surface treatment agent) 72 parts by weight of epoxy silica and 2 parts by weight of carnauba wax as a mold release agent were added and mixed.Then, this was melt-kneaded for 5 minutes on a roll machine at a temperature of 80 to 90°C, and immediately It was cooled to solidify and pulverized.

Thereafter, this pulverized product was molded into a tablet shape, and one of the present invention K
These four types of epoxy resin compositions (Sample Todoroki 1 in Table 1)
-4) were prepared.

For comparison, as shown in Table 1, only zinc di-n-gutyldithiophosphate was used as an additive.

Or, three types of comparative epoxy resin compositions (Samples A [1 to C5) were prepared using only isopropyl tristearyl titanate and no additives, and using the same ingredients and blending amount as above, except for the same conditions as above. .

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

In order to test the performance of the samples that were run through a transfer molding machine at 175"'C for 13 minutes, the samples were subjected to a pressure puller test at 121 DEG C., 2 & Lm, with a bias of 12 V in saturated steam.

Accordingly, the average lifespan of each sample was measured and its moisture resistance was evaluated. The results are shown in Table 2. The average life here refers to the average time (hr, 50% average for a plurality of samples) until the aluminum wiring or electrode is corroded and loses electrical conductivity.

As is clear from Table 2, when the epoxy resin composition according to the present invention is used, even under high temperature and high humidity, compared to the conventional comparative composition.

It can be seen that the resin composition of the present invention is extremely useful as a sealing resin for electrical parts as the average life is significantly improved.

'JJ1 table

Claims (5)

[Claims] (1) An epoxy resin composition comprising an epoxy resin, a curing agent, and an additive comprising one or both of dithiophosphoric acid or a dithiophosphoric acid derivative and an organic titanium 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) The epoxy resin composition according to claim (1), wherein the dithiophosphoric acid derivative is one or both of a dithiophosphoric acid metal salt and a dithiophosphoric acid ammonium salt. (4) One or both of dithiophosphoric acid or dithiophosphoric acid derivatives is 0.0 parts by weight per 100 parts by weight of the epoxy resin.
The epoxy resin composition according to claim (1), comprising 5 to 10 parts by weight. (5) The epoxy resin composition according to claim (1), wherein the organic titanium compound is blended in an amount of 0.01 to 5 parts by weight per 100 parts by weight of the epoxy resin.