JPH02138329A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. retaining a high glass transition temp. and having a low elasticity and low thermal expansion by compounding an epoxy resin, an optionally incorporated phenol resin curing agent, a curing accelerator, a filler and a specified silicone compd. CONSTITUTION:An epoxy resin (A), a phenol resin curing agent (B) incorporated if necessary, a curing accelerator (C), a filler (D) and a silicone compd. (E) are compounded. The component E is an organopolysiloxane (a) having two or more vinyl groups directly bound with Si in the molecule, a hydrogenorganopolysiloxane (b) having 2 or more hydrogen atoms directly bound with Si in the molecule, an organopolysiloxane (c) contg. an epoxy group and a polyalkylene group in the molecule, a platinum (compd.) (d) which is a reaction catalyst for the components (a) and (b) and a compd. (e) obtd. by reacting a phenol resin heated at 100-200 deg.C in advance. An epoxy resin compsn. retaining a high glass transition temp. and having excellent low elasticity and low expansion and suitable for a sealing resin for a semiconductor device and other electronic circuit parts.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an epoxy resin composition that maintains a high glass transition temperature, has low elasticity and low thermal expansion, and is suitably used for electrical and electronic parts.

(Prior art and problems to be solved by the invention) Conventionally, a packaging method has been used in which electronic components such as diodes, transistors, IC11, SI, etc. are sealed using epoxy resin. The stop is glass,
It has been widely put into practical use because it is economically advantageous compared to hermetic sealing methods using metals and ceramics. However, with this resin encapsulation, the element is directly encapsulated with resin by transfer molding, so the element may be distorted or damaged due to the difference in linear expansion coefficient and thermal stress between the element and the resin, and the bonding line may be distorted or damaged. Since there are problems such as disconnection and poor electrical continuity, it is desired to reduce the stress on the element. Particularly in recent years, as semiconductor devices have become larger and more highly integrated, the demand has become stronger. Therefore, in order to reduce the stress on the element, materials have been devised to lower the elastic modulus and linear expansion coefficient of the cured product (sealing resin), and one way to reduce stress is to add flexibility. Methods of blending agents are known.

However, when a flexibility imparting agent such as conventionally known polypropylene glycol diglycidyl ether or bisphenol A type epoxy resin with a long side chain is blended, although a low elastic modulus effect is observed, at the same time the glass transition temperature (Tg) is sudden.

Another problem is that the electrical properties at high temperatures deteriorate because of the rapid drop.

Furthermore, when a Talesol novolac type epoxy resin modified with a rubber having unsaturated double bonds is used as a flexibility imparting agent, the elastic modulus may be lowered, but at the same time the glass transition temperature is also considerably lowered. (Japanese Patent Application Laid-open No. 5 EI-174416, Japanese Patent Application Laid-Open No. 6
No. 0-8315).

Furthermore, in recent years, epoxy resin compositions containing silicone oil have been reported as stress-reducing materials that also improve heat resistance and moisture resistance (Japanese Patent Laid-Open No. 54-54168).
However, silicone oil may bleed onto the molded product or contaminate the mold. Therefore, LSI and VLSI
The fine dispersion of silicone oil or rubber particles required for this purpose has not been achieved, and at present, no resin composition that makes full use of such silicone is known.

Therefore, an object of the present invention is to provide an epoxy resin composition that maintains a high glass transition temperature and has excellent low elasticity and low thermal expansion properties and is suitable for use as a sealing resin for semiconductor devices and other electronic circuit components. It's about making chinogu.

[Means to solve the problem]

As a result of various studies, the present inventors have found that by reacting a curable organopolysiloxane with a phenol resin in advance, it is possible to stably disperse the organopolysiloxane in the form of fine rubber particles, and the above objective has been achieved. I found out that this happens.

The present invention was made based on the above findings, and includes (a) an epoxy resin, Φ) a phenolic resin curing agent added as necessary, (c) a curing accelerator, (d) a filler, and the following (e)
An object of the present invention is to provide an epoxy resin composition characterized by containing a silicone compound.

(e) vinyl group-containing organopolysiloxane ([), which has two or more vinyl groups directly bonded to a silicon atom in one molecule;
Hydrodiene organopolysiloxane (n) having two or more hydrogen atoms directly bonded to a silicon atom in one molecule, organopolysiloxane (■) having an epoxy group and a polyoxyalkylene group in one molecule, the above-mentioned vinyl group-containing organosiloxane A silicone compound obtained by reacting platinum or a platinum compound (IV), which is a catalyst for the reaction between polysiloxane (I) and the above hydrogen organopolysiloxane (U), and a phenol resin preheated to 100 to 200°C.

Hereinafter, the epoxy resin composition of the present invention will be explained in detail.

The (a) epoxy resin used in the present invention is not particularly limited, and is a commonly known polyfunctional epoxy compound;
For example, novolak type epoxy resin, bisphenol A
Examples include type epoxy resins, alicyclic epoxy resins, glycinyl ester epoxy resins, and linear aliphatic epoxy resins. The above epoxy resin may be used alone,
Alternatively, a mixture of two or more types may be used. Among the above epoxy resins, novolac type epoxy resins are preferred from the viewpoint of electrical properties, heat resistance, and the like. Examples of the novolac type epoxy resin include cresol novolac type epoxy resin and phenol novolac type epoxy resin.

The preferable epoxy equivalent and softening point of the above epoxy resin are appropriately selected depending on the type of epoxy resin. It is used. Furthermore, Talesol novolac type epoxy resin has an epoxy equivalent of 180 to 210 and a softening of 60 to 210.
A temperature of 110°C is preferable, and in the case of a phenol novolac type epoxy resin, one having an epoxy weight of 13,160 to 250°C and a softening point of 60 to 110°C is preferable.

(b) As the phenolic resin curing agent, phenol, 0
- Reacting formaldehyde with at least one phenol compound selected from alkyl-substituted phenols such as cresol, m-cresol, p-cresol, ethylphenol, xylenols, p-tert-butylphenol, octylphenol, and nonylphenol; Examples include prepared resins. This phenolic resin curing agent can be added as necessary, and if the amount of phenolic resin used for preparing the silicone compound (e) described later is sufficient, the above phenolic resin curing agent can be added. can reduce the amount,
In addition, there are cases where it is not necessary to add it.

(c) As a curing accelerator, imidazoles such as 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2,4.6-tris(dimethylamino methyl)
Phenol, tertiary amines such as benzyldimethylamine, organic phosphines such as triphenylphosphine, tributylphosphine, methyldiphenylphosphine, tricyclohexylphosphine, 1,8-diazabicyclo(
5,4°0) Undecene-7,1,8-diazabicyclo(7,20) Undecene-8,1,8-diazabicyclo(7,5°O) Tetradecene-8,1,5-diazabicyclo(4°3. 0) Diazabicycloalkenes such as nonene-5,1,5-diazabicyclo(4,2,0)octene-5, and their phenol salts, formates, adipates, and the like. One or more types selected from these groups are used.

(d) Fillers include fused silica, crystalline silica, magnesium oxide, alumina, calcium carbonate, and the like.

The silicone compound (e) used in the present invention includes a vinyl group-containing organopolysiloxane (I) having two or more vinyl groups directly bonded to a silicon atom in one molecule, and a hydrogen bonded directly to a silicon atom in one molecule. Hydrodiene organopolysiloxane (II) having two or more atoms, organopolysiloxane (■) having an epoxy group and a polyoxyalkylene group in one molecule, the above vinyl group-containing organopolysiloxane (I) and the above hydrogen organopolysiloxane It is prepared by reacting platinum or a platinum compound (IV), which is a catalyst for the reaction with polysiloxane (It), and a phenol resin preheated to 100 to 200°C.

Among the above organopolysiloxane components, the vinyl group-containing organopolysiloxane (CI) must always have two or more vinyl groups directly bonded to a silicon atom in one molecule. The reason for this is that when the number of vinyl groups is less than 2, a good silicone crosslinked product cannot be produced.

Furthermore, (n) hydrogen organopolysiloxane is not particularly limited in its structure as long as it has two or more hydrogen atoms directly bonded to a silicon atom in one molecule.
That is, any hydrogen organopolysiloxane that is linear, branched, or cyclic may be used. And the above (II
) The mixing ratio of the components is an amount sufficient to provide 0.75 to 2.5 equivalents of hydrogen atoms directly bonded to silicon atoms per equivalent of vinyl groups directly bonded to silicon atoms in component (I) above. It is preferable.

In addition, (III) an organopolysiloxane having both a polyoxyalkylene group and an epoxy group in one molecule, the polyoxyalkylene group is (I1'ff1OiC
z If a 0h-Hc z If b 0h-R”
(Here, R1 is a divalent organic group, Rt is a hydrogen atom or a terminal capping group, a is 0 or 1, b and C are O to 50 (however,
b+c is 1-100). ), the epoxy group is represented by glycidyl ether or alicyclic epoxy, and organopolysiloxanes having one or more polyoxyalkylene groups and one or more epoxy groups in one molecule are preferred.

Furthermore, platinum or a platinum compound as a catalyst (IV) has conventionally been used as a catalyst for an addition reaction between a vinyl group-containing organopolysiloxane and a hydrogen organopolysiloxane.
Any known material may be used, such as methylvinyl cyclic siloxane platinum complexes, such as chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid and olefins, platinum black, alumina, silica, etc. Examples include those that are supported.

As the phenol resin to be reacted with the organopolysiloxane, the same phenol resin curing agent as shown in (b) above can be used. The temperature at which the phenol resin is heated in advance for reaction is 10
The temperature is 0 to 200°C, preferably 120 to 180°C. If the temperature is less than 100"C, the phenolic resin curing agent will not be melted sufficiently, resulting in insufficient dispersion of the organopolysiloxane, and if it exceeds 200"C, the resin will deteriorate.

Next, the formulation will be explained in detail.

In the combination of (a) epoxy resin and phenolic resin curing agent, it is preferable to use them in a ratio such that the number of phenolic hydroxyl groups is 0.5 to 2.0 per epoxy group contained in the epoxy resin. .

(c) The amount of curing accelerator added is 0 in the epoxy resin composition.
．． 1 to 1.0% by weight is preferred.

(d) The amount of inorganic filler (filler) added is preferably 60 to 85% by weight based on the total composition, and if it exceeds 85% by weight, the fluidity of the composition becomes low and moldability becomes poor. Also,
If it is less than 60% by weight, problems such as an increase in linear expansion coefficient will occur. Therefore, although it varies depending on the type of inorganic filler, the amount added is suitably blended in the range of 60 to 85% by weight.

The amount of all organopolysiloxanes (I) to (III) added is (total epoxy resin + phenolic resin curing agent) 10
It is preferably 3 to 50 parts by weight, and 5 to 40 parts by weight relative to 0 parts by weight! More preferably, it is
If it is less than 3 parts by weight, the elastic modulus decreases little, and if it exceeds 50 parts by weight, Tg, mechanical strength, and electrical properties at high temperatures decrease significantly.

The total amount of organopolysiloxane added is divided into the total amount of vinyl group-containing organopolysiloxane (I), hydrogen organopolysiloxane (n), and platinum or platinum compound (IV) as a catalyst, and the total amount of polyoxyalkylene Weight ratio to the amount of organopolysiloxane (I[I) having both a group and an epoxy group in one molecule; ((I)+
It is best to blend so that (■) + (IV)) / (III) is within the range of 1 to 20. Within this range, the silicone rubber (silicone compound) will be in the epoxy resin matrix. Without secondary agglomeration of the particles,
Moreover, the particle size distribution is 0.1 to 5 μm, allowing for uniform dispersion. When the above weight ratio is less than 1, there is no particular advantage in dispersing the silicone rubber, and moisture resistance and electrical properties deteriorate. Moreover, when the above weight ratio exceeds 20, the dispersibility of the silicone rubber becomes poor and secondary aggregation of particles occurs.

In addition to the ingredients (a) to (e), in the present invention, if necessary, mold release agents such as natural waxes, synthetic waxes, higher fatty acids and metal salts thereof, silane coupling agents, and titanium-based cups may be used. Coupling agents such as ring agents,
Coloring agents such as carbon, flame retardants such as brominated phenol novolak type epoxy resins, brominated bisphenol A type epoxy resins, and flame retardant aids such as antimony dioxide and antimony pentoxide can also be added.

In addition, in the present invention, the ingredients (a) to (e) and other ingredients are blended, mixed with a Henschel mixer, etc., and kneaded at 70 to 110°C with a roll, kneader, etc. to achieve the desired purpose. An epoxy resin composition with excellent properties can be obtained.

〔Example〕

Next, the epoxy resin composition of the present invention will be explained in more detail based on Examples.

The ingredients and raw materials used in Examples and Comparative Examples are shown below, and Table 1 shows the silicone resins prepared and their raw material compositions (parts by weight).

(a) Epoxy resin (I) Orthocresol novolak type epoxy resin (epoxy equivalent weight 197, softening point 73°C) (2) Brominated phenol novolak type epoxy resin (epoxy equivalent weight 275,
Softening point: 84°C) C#3) Phenol resin curing agent: Phenol novolank resin (hydroxyl equivalent: 10B, softening point: 96°C) (c) Curing accelerator: triphenylphosphine (d) Filler: fused silica (e) Raw material for silicone compound Component (r) A vinyl group-containing organopolysiloxane represented by the average compositional formula.

(II) Average compositional formula (Ill) Organopolysiloxane having an epoxy group and a polyoxyalkylene group represented by the average compositional formula (rV) Methyl necessary for crosslinking the organopolysiloxanes of (I) and (II) above Vinylcyclosiloxane platinum complex (f) Other components (I) Mold release agent carnauba wax (2) Coupling agent γ-glycidoxypropyltrimethoxysilane (3) Flame retardant aid antimony dioxide (4) Colorant carbon black Table 1 (Examples 1 to 2) With the raw material composition shown in Table 1 above (numbers represent parts by weight),
Silicone resins A and B were synthesized as shown below.

First, a predetermined amount of phenol resin and triphenylphosphine were placed in a 12 separable flask equipped with a stirrer and a condenser, and heated to 140'C without nitrogen flow to melt the phenol resin. Then, each of the organopolysiloxanes (I), (■), and (■) and the platinum catalyst (IV) were added to the above phenol resin while stirring, and the mixture was allowed to react for 5 hours. After the reaction was completed, the contents were taken out into a stainless steel vat, cooled, and then ground to obtain the desired silicone compound. In addition, the above platinum complex (IV
) was added so that the amount of platinum was 10 ppm based on the total amount of organopolysiloxanes (I) and (II).

Next, each compounded component was mixed under the conditions shown in Table 2 below,
This was kneaded using heated rolls. Then, after cooling, the mixture was pulverized to prepare an epoxy resin molding material (epoxy resin composition). (Example 1 and Example 2 each contain silicone resin A and silicone resin B as blended components.

Test pieces were prepared from the molding materials of these Examples under molding conditions of 175°C for 3 minutes, and after curing at 175°C for 6 hours, the properties were evaluated and the results are shown below in Comparative Example 1.
The results are shown in Table 3 below along with the results of 3.

The bending strength and bending modulus of elasticity are measured according to JISK6911.
Measurement of linear expansion coefficient and glass transition temperature T
It was performed using the MA method. In addition, [embossment during kneading and molding]
When the ingredients were kneaded using a heated roll, the judgment was made based on whether or not the roll surface was stained.

(Comparative Example 1) A test piece was prepared in the same manner as in Example 1, except that organopolysiloxane (Ill) and phenol novolac resin were mixed in the composition shown in Table 2 without reacting in advance. .

(Comparative Example 2) Organopolysiloxanes (I), (II) and (Ill
) and the phenol novolak resin were mixed in the composition shown in Table 2 without reacting them in advance, but all the procedures were as in Example 1.
The same procedure as above was carried out to prepare test pieces as shown in Table 2, Table 3. It has excellent properties and is also characterized by excellent processability since the olkali polysiloxane does not stand out on the surface when the ingredients are kneaded and molded. Therefore, the epoxy resin composition of the present invention has extremely high industrial value.

From the results in Table 3 above, it is clear that the epoxy resin composition of the present invention maintains a high glass transition temperature, and has low elasticity and low thermal expansion.

The present invention has been specifically described above based on examples, but
It goes without saying that the epoxy resin composition of the present invention is not limited to those shown in the above examples.

Claims (1)

[Claims] Comprising (a) an epoxy resin, (b) a phenolic resin curing agent added as necessary, (c) a curing accelerator, (d) a filler, and (e) a silicone compound below. An epoxy resin composition characterized by: (e) Vinyl group-containing organopolysiloxane (I) having two or more vinyl groups directly bonded to silicon atoms in one molecule
, Hydrodiene organopolysiloxane (II) having two or more hydrogen atoms directly bonded to a silicon atom in one molecule, Organopolysiloxane (III) having an epoxy group and a polyoxyalkylene group in one molecule, and the above-mentioned vinyl group-containing A silicone compound obtained by reacting platinum or a platinum compound (IV), which is a catalyst for the reaction between organopolysiloxane (I) and the above hydrogen organopolysiloxane (II), and a phenol resin preheated to 100 to 200°C. .