JPS6042418A - Sealing resin composition - Google Patents

Abstract

PURPOSE:To provide the titled composition scarcely forming ionic or hydrolyzable chlorine and excellent in moisture resistance, containing an epoxy resin, a novolak phenolic resin, magnesium aluminum oxide, and an inorganic filler. CONSTITUTION:A composition containing an epoxy resin, (B) a novolak phenolic resin, magnesium aluminum oxide of the formula (wherein n, m, and X are each >=0.1 integer), and an inorganic filler, wherein said filler is contained in an amount of 25-90wt%, based on the resin composition. The mixing ratio of the novolak phenolic resin is preferably such that the molar ratio of the epoxy groups in the epoxy resin to the phenolic hydroxyl groups in the novolak phenolic resin falls within the range of 0.1-10. the magnesium aluminum oxide used can be obtained by calcining hydrotalcite, for example.

Description

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

[Technical background of the invention and its problems] In recent years, methods have been used to seal electronic components such as diodes, transistors, and integrated circuits using thermosetting resins.

This resin sealing method is economically advantageous compared to hermetic sealing methods using glass, metal, and ceramics! It has been 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. The epoxy resin composition uses curing agents such as acid anhydrides, aromatic amines, and novolak-type phenolic resins. Among these, epoxy resin compositions using novolac-type phenolic resin as a curing agent have excellent moldability and moisture resistance, are non-toxic, and are inexpensive compared to those using other curing agents, so they are suitable for semiconductor encapsulation. Widely used as a material.

However, in epoxy resin compositions, 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 are drawbacks. For these reasons, there has been a desire to develop a sealing resin composition that generates less ionic chlorine and hydrolyzable chlorine and has excellent resistance.

F. 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 to achieve the above object, the present inventors have found that the sealing resin composition described below produces less ionic chlorine or hydrolyzable chlorine than conventional ones. It was found that this product has low moisture content, 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 1y1g n A l m OX [wherein n.

m, x are positive numbers of 0.1 or more] Magnesium aluminum cum oxide (D>inorganic filler is an essential component, and the resin composition (D>inorganic filler is This is a sealing resin composition characterized by containing 25 to 90% by weight.

The epoxy resin (A) used in the present invention is not particularly limited in molecular structure, molecular weight, etc., as long as it is a compound having at least two epoxy groups in its molecule, and can include a wide range of commonly used epoxy resins. can. Examples include aromatic resins such as bisphenol type, alicyclic resins such as cyclohexane derivatives, and epoxy resins such as epoxy novolak resins represented by the following general formula.

(In the formula, R' represents a hydrogen atom, a halogen atom, or an alkyl group, R2 represents a hydrogen atom or an alkyl group, and n represents an integer of 1 or more.) These epoxy resins are used alone or in a mixture of two or more. be able to.

The (B) novolak type phenolic resin used in the present invention includes novolak type phenol resins obtained by reacting phenols such as phenol and alkylphenols with formaldehyde or paraformaldehyde, and modified resins thereof, such as epoxidized or butylated novolaks. Examples include type phenolic resins.

The blending ratio of the novolac type phenolic resin is as described in (A) above.
It is desirable that the molar ratio (a/b) between the epoxy group (a) of the epoxy resin and (B) the phenolic hydroxyl group (b) of the novolac type phenolic resin is within the range of 0.1 to 10. If it is less than 0.1 or more than 10, the moisture resistance, molding workability J3, and electrical properties of the cured product will deteriorate, which is not preferable. Therefore, it is limited to the above range.

(C) Magnesium aluminum oxide represented by the general formula IVIgn Al m OX [where n, m, and x are represented by positive numbers of 0.1 or more] used in the present invention includes one example: M obtained by firing hydrotalcites! :I O, 7A I O, 301, +q. Since this magnesium aluminum oxide absorbs free ionic chlorine and hydrolyzable chlorine into itself, the generation of these free chlorine is reduced. Therefore, by adding this, corrosion disconnection due to free chlorine is eliminated, and a sealing resin composition with excellent moisture resistance can be obtained.

The inorganic fillers used in the present invention (D> include silica powder, alumina, antimony trioxide, talc, calcium carbonate, titanium white, clay, asbestos, mica,
Examples include red iron oxide, glass fiber, and carbon fiber, with silica powder and alumina being particularly preferred. The blending ratio of the inorganic filler is preferably 25 to 90% by weight based on the entire resin composition. If it is less than 25% by weight, there will be no effect on moisture resistance, heat resistance, mechanical properties, and moldability, and if it exceeds 90% by weight, the coverage will be large and moldability will be poor, making it unsuitable for practical use. Therefore, it is limited to the above range.

The sealing resin composition of the present invention includes epoxy resin, novolac type phenol resin, magnesium aluminum oxide 1. An inorganic filler is an essential component, but if necessary, natural waxes, metal salts of straight chain fatty acids,
Mold release agents such as acid amides, esters, paraffins, and chlorinated paraffins.

Flame retardants such as bromotoluene, hexabromobenzene and antimony trioxide, colorants such as carbon black and red iron oxide, and silane coupling agents may be appropriately added and blended.

A general method for preparing the sealing resin composition of the present invention as a molding material includes epoxy resin, novolac type phenolic resin, magnesium/)1luminium oxide, inorganic filler, and other prescribed compositions. After mixing the raw material composition selected according to the ratio sufficiently uniformly using a mixer, etc., it is further melted and mixed using hot rolls, or mixed using a kneader, etc., and then cooled and solidified and pulverized to an appropriate size to form a molding material. obtain.

When the encapsulating resin composition according to the present invention is applied to encapsulating, covering, 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 little ionic chlorine or hydrolyzable chlorine, is free from corrosion, and has excellent moisture resistance, so it can be used for electronic or electrical parts. When used for sealing etc., sufficient reliability can be obtained.

[Examples of the Invention] The present invention will be specifically explained by 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 phenol resin (phenol equivalent: 107) 12%, Mgo7A+ 0.30
．． ,．． 51% and 69% silica powder were mixed at room temperature.9
After kneading and cooling at 0 to 95°C, the mixture was pulverized 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 hardened to produce a molded product. This molded article was subjected to chlorine quantitative determination and moisture resistance testing, and the results are shown in Table 1.

Example 2 Talesol novolac epoxy resin (epoxy equivalent weight 21
5>16%, 8% of novolak type phenolic resin (phenol base 107), 30.155% of M (JO,7A lo) and 70% of silica powder were treated in the same manner as in Example 1 to obtain a molding material, Next, a molded article was obtained.The obtained molded article was subjected to chlorine quantitative determination and moisture resistance test, and the results were used in the first article.
Shown in the table.

Comparative Example Talesol novolak epoxy resin (1 boxy ff1
215), 10% novolac type phenol resin (phenol 1107) and 70% silica powder were treated in the same manner as in the example to prepare a molding material, and then a molded article was made. This molded article was subjected to chlorine window b1 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 aluminum wirings was transfer-molded at 170'C for 3 minutes, and then cured at 180C for 8 hours. In this way, 100 977J sealed electrical components were subjected to a moisture resistance test in high-pressure steam at 120° C., and the time required for 50% disconnection (defect occurrence) due to aluminum corrosion was evaluated.

Patent applicant: Toshiba Chemical Corporation

Claims (1)

[Claims] 1 (A> Epoxy resin (B) Novolac type phenolic resin (C) General formula Mg'n At m OX [In the formula, n
. A sealing resin composition characterized by containing 25 to 90% by weight.2 Molar ratio of epoxy W (a) of the epoxy resin to phenolic hydroxyl group (b) of the novolac type phenolic resin (
The sealing resin composition according to claim 1, wherein a/b) is within the range of 0.1 to 10.