JPS6040124A - Resin composition for sealing - Google Patents

Abstract

PURPOSE:The titled resin evolving a small amount of ionic chlorine and hydrolyzable chlorine, having improved humidity resistance, consisting of epoxy resin, novolak phenolic resin, Mg.Al.hydroxy.carbonate hydrate and a filler. CONSTITUTION:(A) Epoxy resin is blended with (B) novolak phenolic resin in amounts to give a molar ratio of epoxy group a of the component A to phenolic hydroxyl group b of the component B of a/b=0.1-10, (C) basic magnesium aluminum hydroxy carbonate hydrate (hydrotalcite, etc.), and (D) 25-90wt% (based on the resin composition) inorganic filler, to give the desired composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a 1" heavy duty resin composition that generates little ionic chlorine or hydrolyzable chlorine and has excellent moisture resistance.

[Technical Background of the Invention and Problems thereof] In recent years, a method of -C sealing electronic components such as diodes, transistors, and integrated circuits using a thermosetting resin has been used. This method of sealing with resin is economically advantageous compared to hermetic sealing methods using glass, metal, or ceramic, and is therefore widely put into practical use. Among thermosetting resin compositions, epoxy resin compositions are most commonly used as sealing resin compositions in terms of reliability and cost. Epoxy resin compositions use curing agents such as acid anhydrides, aromatic amines, and novolac-type phenolic resins. Among these, epoxy resin compositions using novolac-type phenolic resin as a curing agent are popular for semiconductor encapsulation because they have excellent moldability and moisture resistance, are nontoxic, and are inexpensive compared to those using other curing agents. It is widely used as a food.

However, epoxy resin compositions have the disadvantage that ionic chlorine and hydrolyzable chlorine generated during the epoxy resin manufacturing process remain as impurities, causing corrosion of aluminum wiring in moisture resistance tests, resulting in poor moisture resistance. There is. For these reasons, it has been desired to develop a sealing resin composition that generates less ionic chlorine and hydrolyzable chlorine and has excellent moisture resistance.

[Purpose of the Invention] The present invention was made in view of the above-mentioned drawbacks, and its purpose is to provide a sealing resin composition that generates less ionic chlorine or hydrolyzable chlorine and has excellent moisture resistance. This is what we are trying to provide.

[Summary of the Invention] As a result of intensive research aimed at achieving the above object, the present inventors have discovered that the sealing resin composition described below has a higher content of "C ionic chlorine or hydrolyzable chlorine" than conventional ones. Occurrence is low,
It has been found that it has excellent moisture resistance and is suitable for use in sealing resin compositions.

That is, the present invention provides (A) an epoxy resin (B) a novolac type phenolic resin (C) a general formula Ma , AI IIl <0f-1) x
CO3'VH20 [in the formula, n, m, x, and y do not represent positive numbers of 1 or more, and are basic magnesium represented by 1.
Aluminum hydroxy carbonate hydrate (D) An inorganic filler is an essential component, and the inorganic filler (D) is contained in an amount of 25 to 90% by weight based on the resin composition. Resin composition (・Yes.

As long as the (A) 1-boxy resin used in the present invention is a compound having at least two layers of epoxy groups in its molecule, there are no particular restrictions on the molecular structure or between molecules, and commonly used resins can be used. can be included. Examples include aromatic resins such as bisphenol type, 5 group resins such as cyclohexane derivatives, and poxy novolak resins represented by the following general formula (wherein R1 is a hydrogen atom, a halogen atom, or R2 is a hydrogen atom or an alkyl group, n is an integer of 1 or more (Table 1) These epoxy resins can be used alone or in a mixture of two or more.

The novolak type phenolic resin (B) used in the present invention is a novolak type phenol resin obtained by reacting phenols such as phenol or alkylphenol with formaldehyde or paraformaldehyde, and modified resins thereof, such as ■boxylated or butyl Chemical novolak type phenol resins and the like can be mentioned. The blending ratio of the novolac type phenolic resin is as described above in (A)J.
It is desirable that the molar ratio (a/b) between the 1-boxy group (a) of the -boxy resin and the phenolic hydroxyl group (b) of the novolac type phenol resin (B) is within the range of 0.1 to 10. If the molar ratio is less than 0.1 or more than 10, the moisture resistance, molding workability, and electrical properties of the cured product will deteriorate, which is undesirable.

Therefore, it is limited within the above range.

The basic magnesium aluminum hydroxy carbonate hydrate (C) used in the present invention is, for example, hydrotalcium 1 to Mg6 Al 2 (OH), CO3 4H, which are produced as natural minerals.
20 and synthetic M (Ill, sp, +2 (o)I),
, CO, 3.5H20, etc. This basic magnesium aluminum hydroxy carbonate hydrate absorbs free ionic chlorine and hydrolyzable chlorine into itself, thereby reducing the generation of free chlorine. Therefore, corrosion due to free ions is eliminated, there is no disconnection, and moisture resistance is improved.

Examples of the inorganic filler (D) used in the present invention include silica powder, alumina, antimony trioxide, talc, calcium carbonate, ditambo wide, clay, asbestos, mica, red iron, glass mat, carbon fiber, etc. In particular, silica Powders and alumina are preferred. The blending ratio of the inorganic filler is 25 to 90% of the total resin composition.
It is desirable to contain % by weight. If it is less than 25% by weight, it has no effect on moisture resistance, heat resistance, mechanical properties, or moldability, and if it exceeds 90% by weight, burrs become large and moldability is poor, making it unsuitable for practical use. Therefore, it is limited to the above range.

The sealing resin composition of the present invention contains an epoxy resin, a novolac type phenolic resin, basic magnesium aluminum hydroxy carbonate hydrate, and an inorganic filler as essential components, but if necessary, for example, natural Waxes, metal salts of straight chain fatty acids, acid amides, esters, mold release agents such as paraffins, chlorinated paraffins, flame retardants such as bromine, toluene, hexabromobenzene, antimony trioxide, carbon black, red iron. Coloring agents such as, silane coupling agents, etc. may be added and blended as appropriate.

A general method for preparing the sealing resin composition of the present invention as a molding material is as follows: epoxy resin, novolac type phenol resin, salt M magnesium aluminum hydride oxygen carbonate 1~,
After thoroughly mixing the inorganic filler and other raw material components selected at a predetermined composition ratio using a mixer, etc., heat [1
The mixture is melt-mixed using a kneader or the like, and then solidified using cold fl11 and pulverized to an appropriate size to obtain a molding material.

When the encapsulating resin composition of the present invention is applied to encapsulating, coating, insulating, etc. electronic or electrical components, it is possible to provide components with excellent properties and high reliability.

[Effects of the Invention] The sealing resin composition of the present invention generates less ionic chlorine or hydrolyzable chlorine, is free from corrosion, and has excellent moisture resistance, so it is suitable for electronic and electrical applications. When used for sealing parts, etc., sufficient reliability can be obtained.

[Examples of the Invention] The present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples.

In the Examples and Comparative Examples below, "%" means "% by weight".

Example 1 Talesol novolak epoxy resin (epoxy 121
5) 18%, novolak type phenolic resin (phenol equivalent 107) 12%, Mg6Al2(01-(
), 301% CO3.4H, and 69% silica powder were mixed at room temperature, kneaded at 90 to 95°C, cooled, and then ground to obtain a molding material. The obtained molding material was made into a tablet, injected into a mold that had been preheated and heated to 170°C by transfer molding, and cured to obtain a °C molded product. This molded article was subjected to chlorine determination and moisture resistance tests, and the results are shown in Table 1.

Example 2 Cresol novolac epoxy resin (earth boxy equivalent weight 21
5) 1e% Novosic type phenolic resin ()lNol mother 107) 8%, M (I a5Δ1゜(OH)+s
205% CO3.5H and 10% silica powder were treated in the same manner as in Example 1 to obtain a molded product. The results are shown in Table 1.

Comparative example Cresol novolak epoxy resin (epoxy!t2
15) 20%, novolac type phenolic resin (107) 10%, and 70% silica powder were treated in the same manner as in the example to obtain a molding material, and then a molded article was made. This molded article was subjected to chlorine determination J5 and moisture resistance tests, and the results are shown in Table 1.

Table 1*1: Using the sealing resin composition, an electrical component having two -C aluminum wirings was transfer-molded at 170°C for 3 minutes, and then cured at 180°C for 8 hours. The 100 sealed electrical components obtained in this way were subjected to a moisture resistance test in high-pressure steam at 120°C, and 50% of the electrical components were disconnected due to aluminum corrosion.
The time at which defects occurred was evaluated.

Patent applicant: Toshiba Chemical Corporation

Claims (1)

[Claims] 1 (A) Epoxy resin (B) Novolak phenolic resin (C) General formula MgnAl m (OH) x Co3'
V H20 [wherein n, m. x, y represent positive numbers of 1 or more] A basic magnesium aluminum hydroxy carbonate hydrate (D) inorganic filler is an essential component, and the above (D) inorganic filler is an essential component of the resin composition. A sealing resin composition characterized by containing 25 to 90% by weight of a filler. 2. A patent characterized in that the molar ratio (a/b) between the epoxy group (a) of the epoxy resin and the phenolic hydroxyl m (b) of the novolac type phenolic resin is within the range of 0.1 to 10. The sealing resin composition according to claim 1.