JPS6162514A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide the titled low-stress composition having excellent molda bility, moisture resistance, and crack resistance caused by thermal shock, and useful for the sealing of semiconductor, etc., by uniformly dispersing or reacting and fixing a specific synthetic rubber in an epoxy resin component. CONSTITUTION:The objective composition can be prepared by (1) melting and mixing (A) an epoxy resin (e.g. bisphenol-type epoxy resin) and (B) a synthetic rubber containing epoxy group at the terminal or in the molecular chain, preferably in the presence of (C) one or more compounds selected from tertiary amine, its derivative, organic phosphine compound, organic Al compound, titanium compound, and acid, and (2) compounding the obtained mixture e.g. to (D) an epoxy resin hardener, a cure accelerator, a filler, a mold-release agent, a surface-treating agent, and if necessary, other epoxy resin, etc.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a low stress epoxy resin composition that has excellent crack resistance and moisture resistance when subjected to thermal shock.
Its characteristics can be improved by uniformly dispersing synthetic rubber containing epoxy groups at the ends or within the molecule into the resin, or by reacting and fixing it with the resin component.

[Prior art]

Various low-stress epoxy resin compositions using synthetic rubber have been studied in the past, but both when adding synthetic rubber and when using synthetic rubber-modified epoxy resin, moldability (especially curability, parity) There were problems with the construction of the building (e.g., detachability), etc. For example, when a carboxyl group-containing diene-based rubbery polymer is added [JP-A-58-176958]
In this case, not only did the rubber elute and formability was problematic, but it also contained a hydrophilic carboxyl group, resulting in significantly poor moisture resistance. Further, even when a carboxyl group-containing diene-based rubbery polymer is pre-reacted with an epoxy resin, it tends to be thermally decomposed and has the same drawback as addition.

Various low stress resin compositions that do not use synthetic rubber are also being studied. For example, using a silicone-modified resin), a method of adding silicone [JP-A-56-129
No. 246, JP-A No. 58-47014, etc.), but they not only have the same drawbacks as rubber-modified epoxy resins, but also have the problem of being expensive, that is, lacking in versatility. .

Epoxy resin compositions have superior moisture resistance compared to phenolic resin compositions and polyester resin compositions. For example, it is used in circuit boards, semiconductor sealing materials, and the like. Currently, there is a strong demand for lower stress in these applications, especially in connection with sealing materials. This is to internationalize the final product, allowing it to be used at any time and place.

In other words, because it is used in many different ways and by many people,
They are required to be resistant to rough handling and rapid temperature changes.

[Purpose of the invention]

The present invention improves these drawbacks of low-stress epoxy resin compositions made of synthetic rubber, which conventionally had problems with moldability and could not be applied at the market level, and can be applied at the industrial level. As a result of research aimed at developing practical products, we found that by uniformly dispersing synthetic rubber containing epoxy groups at the ends or within the molecule into a resin component, or by reacting and fixing it with the resin component, it is possible to achieve the desired molding. It has been discovered that a low stress epoxy resin composition can be obtained which has excellent properties such as hardness, moisture resistance, and crack resistance when subjected to thermal shock.

[Structure of the invention]

The present invention includes (1) a heat-melted mixture of an epoxy resin and a synthetic rubber containing an epoxy group at the end or in the molecule, a curing agent, a curing accelerator, a filler, a mold release agent, and a surface treatment. An epoxy resin composition (2) containing an epoxy resin and an epoxy group at the end or in the molecule, a tertiary amine or a derivative thereof, A curing agent, a curing accelerator, and a filler, characterized by containing a mixture heated and melted in the presence of one or more selected from organic phosphine compounds, organic aluminum compounds, titanium compounds, and acids;
It is an epoxy resin composition comprising a mold release agent, a surface treatment agent, and other epoxy resins as necessary.

As used herein, epoxy resins refer to all resins having epoxy groups. For example, it refers to bisphenol epoxy resin, novolac type epoxy resin, triazine nucleus-containing epoxy resin, etc.

Synthetic rubber containing an epoxy group at one end is a diene rubbery polymer having an epoxy group at one or both ends that can react with a curing agent, preferably having epoxy groups at both ends. In addition, synthetic rubber containing epoxy groups in the molecule refers to diene-based rubbery polymers having one or more epoxy groups that can react with a curing agent in the molecule, and - the number of epoxy groups per molecule. The number is preferably 2 to 15, particularly preferably 3 to 10. The molecular weight of epoxy group-containing synthetic rubber is SO
O to 10QOOO, preferably 500 to IQOOO1, particularly preferably 700 to 3ooo. Examples of commercially available synthetic rubbers containing epoxy groups include R-4.
5EPI, EPT (Idemitsu Petrochemical), Nl5S
Examples include O-PB-BF resin (Nippon Soda), 8-stone polybutadiene E series (Nippon Petrochemical), and the like.

Such synthetic rubbers containing epoxy groups at the ends or within the molecule not only have excellent compatibility with epoxy resins and are easy to disperse uniformly, but also can be heated and melt-mixed in the absence or presence of a catalyst. Yes, it reacts easily and immobilizes. By using this, a low-stress epoxy resin composition was obtained in which the synthetic rubber does not easily dissolve out of the resin, has excellent moldability, and has excellent crack resistance when subjected to thermal shock. .

The curing agent mentioned here is preferably phenol novolacs, but may also include acid anhydrides and amines. These may be used alone or in combination. Phenol novolacs refer to all compounds containing a phenolic hydroxyl group or a derivative thereof in the novolak skeleton. It includes not only single-component novolaks of phenols (phenol, alkylphenol, resorcinol, etc.), but also co-condensed novolacs of any combination of phenols, and co-condensed novolaks of phenols and other resins.

Examples of reaction catalysts include tertiary amine or its derivatives trimethylamine, triethylamine, 2.3.4.6
．． 7.8.90.10-octahydro-pyramide (1
12a) Azepine, etc. or quaternary ammonium salts thereof ■Organophosphine compounds (a) First, 'IX 2, tJ 3 phosphine: octylphosphine, diphenylphosphine, butylphenylphosphine, tricyclohexylphosphine, triphenylphosphine, etc. b) Betaine type adducts of organic tertiary phosphine and compounds having a π bond: maleic anhydride-triphenylphosphine adduct, thioisocyanate-triphenylphosphine adduct, diazodiphenylmethane-triphenylphosphine adduct, etc. 1' ( c) Yes m * Suhoniu A tlL: (if!'s PGI112
$ )eCle.

Cl253pEt )eIe 1(a3pEt )ΦB
r"etc ■ Organoaluminum compound (a) A/, C0R)3 (R: H, alkyl group,
Aryl group, aryl group-containing hydrocarbon group]: aluminum isopropoxide, aluminum n-butoxide,
aluminum tert-butoxide, aluminum 5e
e-butyrate, aluminum benzoate, etc. (b)
Beta-diketone complexes of aluminum (aluminum chelate) Nialuminum acetylacetonate, aluminum triple-oacetylacetonato, aluminum pentafluoroacetylacetonato, etc.; ■Titanium compounds butyl titanate, titanium white, etc.; ■Acids such as para-toluenesulfonic acid, etc. be able to.

Note that as the ratio of epoxy group-containing synthetic rubber to epoxy resin 7 increases, the stress decreases; however, the reactivity of epoxy resin 7 decreases. The characteristics can be maximized by selecting the mixing ratio and molecular weight of the epoxy group-containing synthetic rubber/epoxy resin, and the ratio of use in the composition depending on the purpose. Particularly for low-pressure epoxy resin-encapsulated molding materials, it is preferable that the proportion of the epoxy group-containing synthetic rubber in the molding material is 0.1 to 5% by weight. l) In a range other than the above, disadvantages such as poor moldability may occur.

〔Effect of the invention〕

According to the method of the present invention, it is possible to obtain a low-stress epoxy resin composition that has excellent moldability, moisture resistance, and excellent clubbing and scuffing resistance when subjected to thermal shock. Particularly in semiconductor encapsulation applications, it is expected that plastic packaging will be increasingly used in the future, and as a result, there is a demand for low stress in plastics, so the present invention plays a very important role in industry.

〔Example〕

The following is an explanation using a study example of molding materials for semiconductors and soil. All parts used in the examples are parts by weight. The examples according to the present invention are superior in moldability, moisture resistance, and crack resistance compared to comparative examples using conventional techniques, and have high added value that can be used industrially. The epoxy group-containing synthetic rubber is as follows.

Synthetic rubber A: 1,4 trans-type polybutadiene containing epoxy groups at both terminals (epoxy equivalent: 1450) Synthetic rubber B: 1.4 trans-type polybutadiene containing epoxy groups within the molecule (number average molecular weight: 3 ooo, epoxy equivalent: 200) Synthetic rubber C: Molecule Synthetic rubber D 1,2 vinyl type polybutadiene containing internal epoxy groups (number average molecular weight L000, epoxy equivalent weight 190) Synthetic rubber E : 1,2 vinyl type polybutadiene containing epoxy groups in the molecule (number average molecular weight L8001 epoxy equivalent weight 220) The reaction catalyst used in this example is as follows.

Catalyst α Nitriphenylphosphine catalyst β Nialuminum acetylacetonato catalyst γ: 2.
3.4.6.7.8, 9.10-octahydrobyramide (1,2-a) acevin Examples 1 to 7 Epoxy group-containing synthetic rubber X part and epoxy resin (Asahi Chipa: ECN-1273) 7 parts were heated and mixed at 150°C for 1 hour in the presence and absence of a reaction catalyst, then cooled and pulverized to give 7[
A synthetic rubber-modified epoxy resin was obtained. To these synthetic rubber-modified epoxy resins, 70 parts of fused silica (Tatsumori), 0.4 parts of surface treatment agent (Nippon Unicar A-186), and 20-yiL of epoxy resin (Order Chemical ESCN-1028)
Phenol novolac (order made by Bakelite) 10 parts, curing accelerator (KAI Kasei PP-360/Shikoku Kaseikyo = 9/1) 0.2 parts, pigment (Mitsubishi Kasei) 0.5 parts, mold release agent (Hoechst Japan Hoechst) OP/Hoechst S = 1
/1) 0.4 part was added and mixed, and then kneaded in a co-kneader to obtain seven types of epoxy resin compositions. As a result of measuring the moldability and crack resistance of these molding materials, it was found that they were superior to the comparative examples as shown in the table. Moreover, the more synthetic rubber there is, the better the crack resistance is, but when it is too much, the moldability is poor.

Comparative Example 1 Terminal carboxyl group polyisoprene (Clan: LIR-
403) 2 parts and epoxy resin (Asahi Chipa: ECN-1
273) After heating and mixing 20 parts at 150°C for 1 hour, cooling and pulverizing, 70 parts of fused silica, 0 and 4 parts of surface treatment agent,
10 parts of phenol novolak, 0.2 part of curing accelerator, 0.5 part of pigment, and 0.4 part of mold release agent (all the same raw materials as in the example) were added, and the material was prepared in the same manner as in the example. The results of the moldability, crack resistance, and moisture resistance of this material are shown in the table, and the material is significantly inferior to the Examples in terms of moldability and moisture resistance.

Comparative Example 2 2 parts of carboxyl group-containing acrylonitrile-butadiene copolymer (Hiker CTBN1300 After heating and mixing in the presence of the mixture, cooling and pulverizing, 70 parts of fused silica, 04 parts of surface treatment agent, and 1 part of hardening agent were added.
0 parts, curing accelerator 0.2 parts, pigment 0.5 parts, mold release agent 0.
4 parts (all the same raw materials as in the example) were added, and the material was prepared in the same manner as in the example. The results of the moldability, crack resistance, and moisture resistance of this material are shown in the table, and the material is significantly inferior to the Examples in terms of moldability and moisture resistance.

Comparative Example 3 70 parts of fused silica, 20 parts of epoxy resin, 10 parts of phenol novolak, 0.4 part of surface treatment agent, 0.0 parts of curing accelerator.
2 parts of pigment, 0.5 part of pigment, and 0.4 part of mold release agent (all the same raw materials as in Examples) were mixed and kneaded in a co-kneader to obtain an epoxy resin composition. The results of the moldability, crack resistance, and moisture resistance of this molding material are as shown in the table, and as shown in the table, it is significantly inferior to the Examples in terms of crack resistance.

*1.16 pin Judgment based on the degree of occurrence of paris on the lead bin when forming DIP (exceeded)D Judging by the number of cracks generated/total number given for 200 cycles *3TST, 165℃ (2 minutes) 15
200 cycles of thermal shock of 0←℃ (2 minutes) and judgment based on the number of cracks generated/total number *4 Moisture resistant, aluminum, aluminum simulating element sealed 16 pi
nDIP for 1000 hours at 135℃ and 100q6
Determined by defective rate/number of meters due to aluminum corrosion during storage

Claims (2)

[Claims] (1) An epoxy resin composition comprising a heat-melted mixture of an epoxy resin and a synthetic rubber containing an epoxy group at the end or within the molecule. (2) Epoxy resins and synthetic rubber containing an epoxy group at the end or within the molecule, a tertiary amine or its derivative, an organic phosphine compound, an organic aluminum compound,
An epoxy resin composition comprising a mixture heated and melted in the presence of one or more selected from titanium compounds and acids.