JPH0655805B2 - Thermosetting epoxy resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermosetting epoxy resin composition, and in particular,
The present invention relates to a composition useful for packaging electronic and electric parts.

[Conventional technology]

Various thermosetting resins are used for packaging electronic and electric parts. Among them, epoxy resin is the most excellent because it has excellent mechanical properties, electrical properties, heat resistance, adhesiveness, and moldability. Widely used in large quantities. The package of electronic parts is in the direction of thinning and miniaturization as represented by IC, but the conventional epoxy resin composition has a drawback that the package is easily cracked when subjected to a cooling / heating cycle. . As a method of solving this drawback, a method of mixing a spherical silicone powder with an epoxy resin (JP-A-59-96122) and a method of mixing a silicone fine powder treated with a silane coupling agent with an epoxy resin (JP-A-59-96122) Japanese Laid-Open Patent Publication No. Sho 61-101519) has been proposed.

[Problems to be Solved by the Invention] However, in the method described in the above-mentioned 2 gazette, since the silicone fine powder blended in the epoxy resin has a low affinity with the epoxy resin, the dispersibility is poor, and the resulting package It has a problem of low moisture resistance.

Therefore, an object of the present invention is to provide a novel thermosetting epoxy resin composition which is less likely to cause cracks in a package due to a heat cycle and has excellent moisture resistance.

[Means for solving problems]

In order to solve the above problems, the present invention provides: (a) 100 parts by weight of epoxy resin, (b) 1 to 100 parts by weight of a curing agent, and (c) an aqueous solution containing a curable organopolysiloxane composition and a surfactant. Obtained by curing in an emulsion state, 0.001-10% by weight based on the weight of the particles
The present invention provides a thermosetting epoxy resin composition containing 1 to 50 parts by weight of a powder composed of silicone elastomer particles containing an amount of a surfactant.

The epoxy resin of component (a) used in the present invention is preferably a compound having at least two epoxy groups in the molecule, but the molecular structure, molecular weight, etc. are not particularly limited. Examples of such epoxy compounds include 2,
Diglycidyl ether of 2'-bis (4-hydroxyphenyl) propane or halide, butadiene epoxide, vinylcyclohexene dioxide, diglycidyl ether of resorcin, 1,4-bis (2,3-epoxypropoxy) benzene, 4, 4'-bis (2,3-
Epoxypropoxy) diphenyl ether, 1,4-bis (2,3-epoxypropoxy) cyclohexene, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 1,2-dioxybenzene or resorcinol, polyphenol or Epoxy glycidyl ether or polyglycidyl ester obtained by condensation of polyhydric alcohol and epichlorohydrin, epoxy novolak obtained by condensation of novolac type phenol resin (or halogenated novolac type phenol resin) and epichlorohydrin, epoxy by peroxide method Examples thereof include epoxidized polyolefin and epoxidized polybutadiene.

As the component (a), a monoepoxy compound may be appropriately used in combination with the epoxy compound having at least two epoxy groups, and the monoepoxy compound may be styrene oxide, cyclohexene oxide,
Propylene oxide, methyl glycidyl ether, ethyl glycidyl ether, phenyl glycidyl ether,
Examples include allyl glycidyl ether, octyl oxide, dodecene oxide and the like.

The component (a) is not necessarily limited to one type in use, and two or more types may be mixed and used.

Next, as the curing agent which is the component (b) used in the present invention, various conventionally known ones can be used, and examples thereof include diethylenetriamine, triethylenetetramine and diethylaminopropylamine. , N-aminoethylpiperazine, bis (4-amino-3-methylcyclohexyl) methane, metaxylyleneamine, menthanediamine, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxa Amine-based compounds such as spiro (5,5) undecane; epoxy resin-diethylenetriamine adduct, amine-ethylene oxide adduct, modified aliphatic polyamine such as cyanoethylated polyamine; bisphenol A, tri-methylol allyloxyphenol, low polymerization degree phenol Novolac resin, Epoxidized or butylated phenolic resin or "Super Beckicte" 1001 (manufactured by Nippon Reichhold Chemical Co. (Ltd.)), "Hitanol" 4010 (Ltd.)
Hitachi, Ltd.), Scado form L. 9 (Netherlands Scado Zw
Oll), Methylon 75108 (manufactured by General Electric Company, USA) and other known phenolic resins;
"Beckamine" P. 138 (Nippon Reich Hold Co., Ltd.)
Made), "Melan" (made by Hitachi, Ltd.), "U-Van" 1
Carbon resin known under the trade name such as 0R (manufactured by Toyo High Pressure Industrial Co., Ltd.); amino resin such as melamine resin and aniline resin; formula, HSC ₂ H ₄ OCH ₂ OC ₂ H ₄ SSn′C ″ ₂ H A polysulfide resin having at least two mercapto groups in the molecule represented by ₄ OCH ₂ OC ₂ H ₄ SH (n ′: an integer of 1 to 10);
Examples thereof include organic acids such as phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, pyromellitic anhydride, methylnadic acid, dodecyl succinic anhydride and chlorendic anhydride, or their anhydrides.

Among the above-mentioned curing agents, phenolic resin (phenol novolac resin) gives the composition of the present invention good molding workability (transfer molding, injection molding, etc.) and is used for resin encapsulation of IC, LSI and the like. It provides excellent moisture resistance and is desirable because it is non-toxic and relatively inexpensive.

The above-mentioned curing agents are not necessarily limited to one type in use, and two or more types may be used in combination depending on the curing performance of the curing agents.

The suitable amount of the component (b) used varies depending on its specific type, but generally 1 to 100 parts by weight, preferably 5 to 50 parts by weight, relative to 100 parts by weight of the component (a). Ranged. This is because when the amount used is less than 1 part by weight,
It becomes difficult to satisfactorily cure the composition of the present invention,
On the other hand, if it exceeds 100 parts by weight, it is economically disadvantageous, and the component (a) is diluted so that it takes a long time to cure, and further, the physical properties of the cured product deteriorate. Is.

Further, the powder (hereinafter referred to as “silicone elastomer powder”) composed of the silicone elastomer particles used as the component (c) in the present invention is a curable organopolysiloxane composition cured in an aqueous emulsion state containing a surfactant. It is necessary to contain the surfactant in an amount of 0.001 to 10% by weight, preferably 0.01 to 1% by weight, based on the weight of the particles. When the amount of this surfactant is less than 0.001% by weight, the silicone elastomer powder of (C) component,
The effect of improving the dispersibility in the epoxy resin which is the component (a) cannot be expected. On the other hand, when it exceeds 10% by weight, the moisture absorption of the obtained cured product increases and the moisture resistance of the package decreases. The surfactant is usually contained in the powder particles and also present on the surface thereof.

The type of silicone elastomer constituting the component (C) is not particularly limited, but R ₂ Si is used as the siloxy unit constituting the component.
O unit (wherein R is the same or different monovalent organic group, such as an alkyl group such as methyl group, ethyl group, propyl group, butyl group, cycloalkyl group such as cyclohexyl group, vinyl group, etc. , Alkenyl groups such as allyl groups, aryl groups such as phenyl groups and xylyl groups, aralkyl groups such as phenylethyl groups, halogenated monovalent hydrocarbon groups such as γ-chloropropyl groups and 3,3,3 trifluoropropyl groups. Alternatively, an epoxy group, an amino group, a hydroxyl group, a carboxyl group, a carboxylic acid ester group and the like are exemplified.) 80% or more is preferable.

The type of surfactant contained in the component (c) is not particularly limited. There are no particular restrictions on the type of surfactant. For example,
As the nonionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, glycerin fatty acid ester, etc .; as the anionic surfactant, fatty acid salt,
Alkyl sulfate ester salt, alkyl benzene sulfonate, alkyl naphthalene sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate ester salt, etc .; as cationic surfactant, alkyl amine salt, quaternary ammonium salt, etc. can give.

The particle size of the particles constituting the component (C) is preferably 50 μm or less in view of dispersibility of the component (A) in the epoxy resin and moldability of the composition of the present invention obtained.

The silicone elastomer powder of component (c) is obtained by curing a curable organopolysiloxane composition in an aqueous emulsion state containing a surfactant to produce elastomer particles, and then separating by a spray dry method or a salt folding method. To be The curable organopolysiloxane composition used is not particularly limited, and the curing method or curing catalyst may be appropriately selected according to the type of curable organopolysiloxane used and is not particularly limited. For example, with a vinyl group bonded to silicon in the presence of a platinum-based catalyst, An organopolysiloxane system that cures by an addition reaction with a bond; and in the presence of a condensation catalyst such as organotin An organopolysiloxane system that is cured by a dehydrogenation reaction with (Wherein R is an alkyl group such as methyl, ethyl, propyl, etc.) and is cured by an dealcoholation reaction to produce an organopolysiloxane system, Examples thereof include an organopolysiloxane type which is cured by a dehydration reaction with.

As described above, various curable organopolysiloxane compositions can be used. Among them, from the viewpoint of reactivity,
(a) a vinyl group-containing organosiloxane, and (b) It is preferable to cure the organohydrogenpolysiloxane having a bond by addition reaction in the presence of the platinum-based catalyst (c).

The vinyl group-containing organosiloxane as the component (a) must have at least two vinyl groups bonded to silicon atoms in one molecule. This organopolysiloxane includes (CH ₂ = CH) SiO _1.5 units, RSiO _1.5 units, R (CH = CH ₂ ) S
iO units, R ₂ SiO units, R ₂ (CH = CH ₂ ) SiO _0.5 units, and
R ₃ SiO _0.5 unit [wherein R is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an aryl group such as a phenyl group or a tolyl group, a cyclohexyl group or hydrogen bonded to a carbon atom of these groups] It is an unsubstituted or substituted monovalent hydrocarbon group excluding an aliphatic unsaturated group such as a vinyl group selected from a group in which some or all of the atoms are substituted with a halogen atom, a cyano group, etc.] Examples thereof include, but the molecular structure thereof may be linear, branched or cyclic. In addition, this organopolysiloxane is usually a linear one in which both ends of the molecular chain are blocked with dimethylvinylsilyl groups, but this vinyl group may be contained in the chain, and the vinyl group content Is
The content is 0.1 mol% or more, and it is preferable that 50 mol% or more of the organic groups other than the vinyl group are methyl groups, and the following are preferable. It may be a mixture of two or more species.

(P = integer from 10 to 600) (M is an integer of 10 to 1000, n is an integer of 2 to 50) Next, the organohydrogenpolysiloxane as the component (b) has at least two hydrogen atoms bonded to silicon atoms in one molecule. Must be included. As this organohydrogenpolysiloxane, HSiO
_1.5 units, R'SiO _1.5 units, R'HSiO units, (R ') ₂ Si
O unit, (R ′) ₂ HSiO _0.5 unit, (R ′) ₃ SiO _0.5 unit and SiO ₂ unit, and R ′ is selected from the same group as R mentioned above. The molecular structure may be linear, branched, or cyclic. The hydrogen atom bonded to the silicon atom in this organosiloxane (≡SiH bond) is generally considered to be contained in the molecular chain, but it may be at the end of the molecular chain, and the amount of this ≡SiH bond is Usually, the number is 2 or more (preferably 3 or more) in one molecule, but it is preferable that 50 mol% or more of the organic groups other than the ≡SiH bond are methyl groups. The following formula is preferable.

(Q is an integer of 0 to 200, r is an integer of 8 to 100) In addition, the platinum-based catalyst as the component (c) is the above (a).
It may be a known one used for the addition reaction between the component and the component (b), which is platinum black, platinum supported on silica or the like, or chloroplatinic acid, an alcohol compound of chloroplatinic acid, chloroplatinic acid. Examples thereof include platinum compounds such as aldehydes, various olefins, and complexes with vinyl siloxane.

The organosiloxane composition comprising the above components (a), (b) and (c) can be obtained by mixing these predetermined amounts. The mixing ratio of the component (a) and the component (b) can be widely varied depending on the molecular weight of these components and the physical properties required as an elastomer after curing, but it is usually the silicon atom in the component (a). Vinyl group bonded to (≡SiC
The molar ratio of (H = CH ₂ ) to the ≡SiH bond in the component (b) is 4: 1 to
It is desirable that the ratio is within the range of 1: 4. Also,
The amount of component (c) added may be a catalytic amount.
If the total amount of the components (a) and (b) is less than 0.1 ppm, this reaction will not be sufficient, and if it is more than 1,000 ppm, the reaction will be too fast and uneconomical, so it is usually in the range of 0.1 to 1,000 ppm, preferably , 1 to 100 ppm.

When the component (c) of the present invention is produced using the above addition reaction type organopolysiloxane composition, first, the vinyl group-containing organopolysiloxane as the component (a) and the organopolysiloxane as the component (b) are prepared. A predetermined amount of hydrogen polysiloxane is mixed to prepare an organosiloxane composition, and then water and a surfactant are added to the composition, which is then emulsified using a commercially available homogenizer or the like.
The surfactant used here may be any as long as it can emulsify the organosiloxane composition,
For example, nonionic emulsifiers such as polyoxyethylene alkyl phenyl ether and polyoxyethylene alkyl ether having an HLB of 10 to 15 are preferable,
These may be used in combination of two or more thereof.

The amount of the silicone elastomer powder of the component (c) used in the present invention described above is 1 to 50 parts by weight, preferably 2 to 3 parts by weight, relative to 100 parts by weight of the epoxy resin of the component (a).
0 parts by weight. If the blending amount is too small, the effect of adding the component (c), that is, the improvement of the durability against heat and cold cycles and the improvement of the moisture resistance is difficult to appear, and if it exceeds 50 parts by weight, the original properties of the thermosetting epoxy resin are impaired. is there.

Further, the thermosetting epoxy resin composition of the present invention contains various additives generally used in the thermosetting epoxy resin composition, in addition to the components (a), (b) and (c) described above. , Can be blended as necessary according to the intended use and purpose. Examples of such additives include inorganic fillers such as fumed silica, fused silica, crystalline silica and alumina; flame retardants such as antimony oxide, halogen compounds and phosphorus compounds; higher fatty acid metal salts and ester waxes. Examples of the internal release agent include silane coupling agents, pigments and dyes.

The thermosetting epoxy resin composition of the present invention can be prepared by uniformly kneading required components with a mixing device such as a roll or a kneader.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the following, "part" and "%" mean "part by weight" and "% by weight", respectively.

Example 1 (1) Both ends of the molecular chain are blocked with dimethylvinylsilyl groups. The viscosity consisting of 96 mol% of dimethylsiloxane units and 4 mol% of methylvinylsiloxane units has a viscosity of 200 cSt (25
Both ends of the molecular chain are blocked with trimethylsilyl groups in 100 parts of methyl vinyl polysiloxane (° C.). ≡Si by adding 10 parts of methylhydrogenpolysiloxane having a viscosity of 28 cSt (25 ° C.) consisting of 95 mol% of methylhydrogensiloxane unit and 5 mol% of dimethylsiloxane unit.
The molar ratio of H / Si-CH = CH ₂ made the organosiloxane composition is 2.0.

Then, 3 parts of polyoxyethylene octyl phenyl ether with HLB = 13.5 and water 587. %, And homogenously mixed by a homomixer, and then homogenized by passing this through a Gaurin homogenizer at a pressure of 300 kg / cm ² , and the emulsion particles of this product have a maximum particle size of 10 μm. , Its volume average particle size is 1.0 μm
Met.

Next, a mixture of 0.2 part of a chloroplatinic acid-olefin complex salt toluene solution (platinum content: 0.05%) and 0.1 part of polyoxyethylene octyl phenyl ether having HLB = 13.5 was added to this emulsion and mixed, and the mixture was mixed at 25 ° C for 20 hours. When left to react, the emulsion particles had a volume average particle diameter of 0.1 μm. Then, spray dryer GA with an inlet temperature of 150 ° C and an outlet temperature of 80 ° C.
Using -31, a spherical silicone elastomer fine powder having an average particle diameter of 5 μm was obtained. This spherical silicone elastomer fine powder contained 2.7% of a surfactant inside or on the surface thereof.

(2) To 15 parts of this spherical silicone elastomer fine powder,
67.9 parts of epoxy cresol novolac resin (EOCN-102, manufactured by Nippon Yakuhin) having an epoxy equivalent of 220, 32.1 parts of phenol novolac resin (MP-120, manufactured by Gunei Chemical), crystalline quartz powder 3
70.5 parts, carbon black 12 parts, carnauba wax 1.2
Part, and 1.3 parts of C ₁₁ Z azine (trade name, manufactured by Shikoku Kasei) as a curing accelerator are uniformly mixed, further kneaded with a hot two roll at 80 to 95 ° C., and then pulverized to obtain a thermosetting epoxy resin. A composition [I] was obtained.

Example 2 (1) To 100 parts of methylvinylsiloxane having a viscosity of 600 cSt (25 ° C.) composed of 100% of dimethylsiloxane units in which both ends of the molecular chain are blocked with a dimethylvinylsilyl group,
Dimethylhydrogen siloxane unit [(CH ₃ ) ₂ HSiO
_0.5 unit] 2.5 mol of methylhydrogenpolysiloxane consisting of 60 mol% and SiO ₂ unit 40 mol% is added and mixed to obtain an organosiloxane composition having a molar ratio of ≡SiH / ≡Si—CH═CH ₂ of 1.5. Had made.

Then, a surfactant and water were added to this product in the same manner as in (1) of Example 1 to prepare an emulsion using a homogenizer.
The volume average particle diameter was 1.2 μm and 0.9 μm.

Then, a platinum chloride-olefin complex salt was added to this emulsion in the same manner as in (1) of Example 1, and the mixture was heated at 50 ° C. for 6 hours to cause a reaction, and the emulsion particles had a volume average particle diameter of 1.1 μm. Became. Next, 50 parts of Glauber's salt was added to 500 parts of this emulsion, and the mixture was stirred at 70 ° C. for 1 hour, whereby fine particles of silicone elastomer were deposited. The resulting slurry is centrifugally dehydrated, washed twice with 5 times the amount of ion-exchanged water, and then dried with a hot air circulation dryer at 50 ° C.
75 g of spherical silicone elastomer fine powder was obtained. The volume average particle diameter of this product was 4 μm. This spherical silicone elastomer fine powder contains 0.05% surfactant.
Its inclusion was confirmed by extraction with isopropyl alcohol (IPA).

(2) Using this spherical silicone elastomer fine powder, a thermosetting epoxy resin composition [I
I] got.

Comparative Example 1 20 g of the spherical silicone fine powder obtained in Example 2 was added to 100 cc
Extraction was carried out three times at 80 ° C. with IPA No. 3 to obtain a silicone elastomer fine powder substantially free of a surfactant. A thermosetting epoxy resin composition [III] was obtained in the same manner as in Example 1 except that this was used.

Comparative Example 2 A thermosetting epoxy resin composition [IV] was obtained in the same manner as in Example 1 (2) except that the spherical silicone elastomer fine powder was not used in Example 1 (2).

Thermosetting epoxy resin composition [I] [II] [III] [I
V] was used to transfer-mold various test specimens under the conditions of a temperature of 160 ° C. and a pressure of 70 kg / cm ² , and then post-cured at 180 ° C. for 4 hours, and the following measurements and tests were performed. The results are shown in Table 1.

Linear expansion coefficient Measured according to JIS K 6911.

Glass transition point Measured according to JIS K 6911.

Flexural modulus was measured according to ASTM D-790.

Cooling / Heat Cycle Test A 0.35 mm thick silicone wafer was cut into a 16 mm × 4.5 mm rectangle and bonded to a 14-pin IC frame (42 alloy). After molding under the above conditions, each composition was post-cured. The obtained test piece was cooled at -55 ° C for 30 minutes and then at 150 ° C for 3 minutes.
A so-called cooling / heating cycle in which heating was performed for 0 minutes was performed, and the number of cycles until the defective rate due to clutch cracking of the molding resin reached 50% was measured.

Humidity resistance test A monitor IC in which an Amyl simulated element was encapsulated with each composition under the above conditions was subjected to a pressure cooker test at 121 ° C, 2
The number of defects n after leaving for 1000 hours at atmospheric pressure / parameter (50) was measured.

[Effect of the invention] As is clear from the results of the examples, the thermosetting epoxy resin composition of the present invention has a low coefficient of linear expansion and a low bending elastic modulus without lowering the glass transition point of the cured product. In the case where a package of an electronic component is formed, cracks are less likely to occur even in a cooling / heating cycle, and moisture resistance is excellent, so that highly reliable packaging can be performed.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Futatsumori 2-13-1, Isobe, Annaka-shi, Gunma Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (56) Reference JP-A-60-65023 (JP, A)

Claims (1)

[Claims] (1) 100 parts by weight of an epoxy resin (b) 1 to 100 parts by weight of a curing agent and (c) a curable organopolysiloxane composition obtained by curing in an aqueous emulsion state containing a surfactant. , 0.001-10% by weight with respect to the weight of the particles
A thermosetting epoxy resin composition containing 1 to 50 parts by weight of a powder composed of silicone elastomer particles containing an amount of a surfactant.