KR20110008048A - Epoxy resin composition and molded object - Google Patents

Abstract

The epoxy resin composition which is excellent in moldability and high in thermal conductivity at the time of compounding with an inorganic filler and giving hardened | cured material excellent in low thermal expansion property and heat resistance and moisture resistance is provided.
This epoxy resin composition contains (A) epoxy resin and (B) hardening | curing agent, and makes 50 weight% or more of an epoxy resin 4,4'- benzophenone type epoxy resin, and makes 50 weight% or more of a hardening | curing agent 4,4 '. It is an epoxy resin composition which set it as the benzophenone type phenolic resin, and made the equivalence ratio of the epoxy group in epoxy resin and the functional group in a hardening | curing agent within the range of 0.8-1.5. This epoxy resin composition can contain 50-95 wt% of inorganic fillers, and is suitable for semiconductor encapsulation.

Description

Epoxy resin composition and molding {EPOXY RESIN COMPOSITION AND MOLDED OBJECT}

The present invention relates to an epoxy resin composition useful for insulating materials for electrical and electronic parts such as semiconductor encapsulation, laminates, and heat dissipation substrates with excellent reliability, and moldings using the same.

Conventionally, as a sealing method of electrical, electronic components such as diodes, transistors, integrated circuits, semiconductor devices, etc., for example, a hermetic seal using an encapsulation method of epoxy resin, silicon resin, etc., or glass, metal, ceramic, etc. The seal method has been adopted. Recently, resin encapsulation by transfer molding, which has improved reliability and is capable of mass production, and has a merit of cost, has become mainstream.

In the resin composition used for the resin sealing method by transfer molding, the sealing material which consists of an epoxy resin and the resin composition which has a phenol resin as a main component of a resin component as a hardening | curing agent is generally used.

Background Art Currently, epoxy resin compositions used for the purpose of protecting devices such as power devices are filled with inorganic fillers such as crystalline silica at high density in order to cope with a large amount of heat emitted by the devices.

In recent years, power devices include one-chips or modular ones incorporating IC technology, and further improvement in heat dissipation and thermal expansion properties of encapsulating materials is desired.

In order to meet these demands, attempts have been made to use crystalline silica, silicon nitride, aluminum nitride, and spherical alumina powders in order to improve thermal conductivity (Patent Documents 1 and 2). Along with the viscosity increase at the time of shaping | molding, there exists a problem that fluidity | liquidity falls and moldability is impaired. Therefore, there was a limit to only the method of increasing the content rate of an inorganic filler.

From the said background, the method by the high thermal conductivity of the matrix resin itself is also examined, For example, patent document 3 and patent document 4 are proposed the resin composition using liquid crystalline resin which has rigid mesogenic group. However, these epoxy resins having mesogenic groups are highly crystalline and high melting point epoxy compounds having rigid structures such as a biphenyl structure and an azomethine structure, and thus have a disadvantage of poor handleability when used as an epoxy resin composition. Further, in order to efficiently orient the molecules in the hardened state, special operations such as hardening by applying a strong magnetic field are required, and in order to be widely used industrially, there have been great limitations on equipment. In addition, in the blending system with the inorganic filler, the thermal conductivity of the inorganic filler is overwhelmingly large compared to that of the matrix resin, and even though the thermal conductivity of the matrix resin itself is increased, there is a reality that it does not contribute significantly to the improvement of the thermal conductivity of the composite material, thereby improving the sufficient thermal conductivity. No effect was obtained.

Patent Document 5 shows a 4,4'-benzophenone type epoxy resin, but the cured product obtained by using an acid anhydride as a curing agent is disclosed as an example, and a controlled cured product having a higher order structure expressing high thermal conductivity is disclosed. It is not granted.

Japanese Patent Laid-Open No. 11-147936 Japanese Patent Laid-Open No. 2002-309067 Japanese Patent Application Laid-Open No. 11-323162 Japanese Unexamined Patent Publication No. 2004-331811 Japanese Patent Laid-Open No. 2-202512

Accordingly, an object of the present invention is to solve the above problems, to provide an epoxy resin composition which is excellent in formability and has a high thermal conductivity when it is complexed with an inorganic filler, and which gives a cured product having low thermal expansion and excellent heat resistance and moisture resistance. It also provides a molding using the same.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that when hardening a specific epoxy resin and a specific hardening | curing agent, after hardening, the controlled molding of a higher order structure is obtained, and the specificity of high thermal conductivity, low thermal expansion, high heat resistance, and high moisture resistance improves specifically, The present invention has been reached.

That is, the present invention, in the epoxy resin composition comprising (A) epoxy resin and (B) hardener, 4,4'- benzophenone-based epoxy represented by the general formula (1) at least 50wt% of the epoxy resin It is set as resin, and 50 weight% or more of a hardening | curing agent is made into 4,4'- benzophenone type phenolic resin represented by following General formula (2), and the equivalence ratio of the epoxy group in epoxy resin and the functional group in a hardening agent is 0.8-1.5. The present invention relates to an epoxy resin composition.

(N represents the number of 0-15.)

(M shows the number of 0-15.)

The epoxy resin composition of this invention can contain an inorganic filler, and it is preferable that content of an inorganic filler in this case is 50-95 wt%. And the epoxy resin composition of this invention is suitable as an epoxy resin composition for semiconductor sealing.

The present invention also relates to a prepreg comprising the epoxy resin composition as a semi-cured state by impregnating a sheet-like fibrous substrate.

The present invention also relates to a molded article obtained by curing and molding the epoxy resin composition. It is preferable that this cured molding satisfies any one or more of the following. 1) the thermal conductivity is 4W / mK or more, 2) the peak of the melting point in the scanning differential thermal analysis is in the range of 150 ° C to 300 ° C, and 3) the endothermic amount in terms of the resin component in the scanning differential thermal analysis. 5 J / g or more.

According to the present invention, there is provided an epoxy resin composition which is excellent in moldability and has a high thermal conductivity when it is complexed with an inorganic filler and which provides a cured product having low thermal expansion and excellent heat resistance and moisture resistance, and further provides a molded article using the same.

4,4'-benzophenone type epoxy resin (also called a benzophenone type epoxy resin) represented by the said General formula (1) An epoxy resin is manufactured by making 4,4'- dihydroxy benzophenone and epichlorohydrin react. can do. This reaction can be performed similarly to a normal epoxidation reaction. For example, after dissolving 4,4'-dihydroxybenzophenone in excess epichlorohydrin, it is 50-150 degreeC in presence of alkali metal hydroxides, such as sodium hydroxide and potassium hydroxide, Preferably it is 60-100 degreeC The method of making it react for 1 to 10 hours can be mentioned. The use amount of alkali metal hydroxide at this time is 0.8-1.2 mol with respect to 1 mol of hydroxyl groups in 4,4'- dihydroxy benzophenone, Preferably it is the range of 0.9-1.0 mol. Epichlorohydrin is used in an excess amount with respect to the hydroxyl group in 4,4'- dihydroxy benzophenone, and is usually 1.5 to 15 mol with respect to 1 mol of the hydroxyl group in 4,4'- dihydroxy benzophenone. After completion of the reaction, excess epichlorohydrin is distilled off, and the residue is dissolved in a solvent such as toluene, methyl isobutyl ketone, filtered, washed with water to remove the inorganic salt, and then the solvent is distilled off. A benzophenone type epoxy resin can be obtained.

In the general formula (1), n is a number from 0 to 15, and the value of n is the molar ratio of epichlorohydrin to 4,4'-dihydroxybenzophenone used in the synthesis reaction of the epoxy resin. It can be adjusted easily by changing. The value of n can be suitably selected according to the application to be used. For example, in the use of a semiconductor encapsulation in which high filling rate of a filler is desired, it is preferable to have low viscosity and crystallinity, and to select in the range of 0.01-1.0 as an average value of n suitably. When larger than this, a viscosity will become high and handleability will fall.

The benzophenone epoxy resin used for this invention can be synthesize | combined using what mixed with 4,4'- dihydroxy benzophenone and another phenolic compound as a raw material. In this case, the mixing ratio of 4,4'- dihydroxy benzophenone is 50 wt% or more. Although there is no restriction | limiting in particular in a phenolic compound, It is preferable that it is bifunctional which has two hydroxyl groups in 1 molecule.

The epoxy resin used for this invention contains 50 wt% or more, Preferably it is 80 wt% or more, More preferably, 90 wt% or more of the benzophenone type epoxy resin represented by General formula (1). Although the epoxy equivalent of this benzophenone series epoxy resin is normally the range of 160-20,000, a suitable epoxy equivalent is suitably selected according to a use. For example, in the use of a semiconductor encapsulation, it is preferable that it is low viscosity from the viewpoint of the high filling rate of an inorganic filler and the improvement of fluidity | liquidity. It is preferable that it is the range of. Moreover, in uses, such as a laminated board, it is the range of 400-20,000 preferably from a viewpoint of film property and flexibility provision.

The form of the benzophenone epoxy resin represented by General formula (1) is also suitably selected according to a use. For example, in the use of a semiconductor encapsulation, since it is often handled as a powder, it is preferable that it is solid crystalline at normal temperature, preferable melting | fusing point is 80 degreeC or more, and preferable melt viscosity in 150 degreeC is 0.005 to 0.2 Pa. s. In addition, in applications, such as a laminated board, since it dissolves in a solvent and is used in many cases, there is no restriction | limiting in particular in the form of an epoxy resin.

The purity of the epoxy resin used in the present invention, particularly the amount of hydrolyzable chlorine, is preferably less from the viewpoint of improving the reliability of the electronic component to be applied. Although not specifically limited, Preferably it is 1000 ppm or less, More preferably, it is 500 ppm or less. In addition, the hydrolysable chlorine used by this invention means the value measured by the following method. That is, 0.5 g of the sample was dissolved in 30 ml of dioxane, 1 N-KOH and 10 ml were added thereto, and the mixture was refluxed for 30 minutes at room temperature. After cooling to room temperature, 100 ml of 80% acetone water was added, followed by a potential difference of 0.002 N-AgNO ₃ aqueous solution. It is the value obtained by performing titration.

In addition to the benzophenone type epoxy resin represented by General formula (1) used as an essential component of this invention, the epoxy resin composition of this invention may use together another epoxy resin which has 2 or more epoxy groups in a molecule | numerator. For example bisphenol A, 4,4'-dihydroxydiphenylmethane, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxydiphenylmethane, 4,4'-dihydrate Oxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfide, fluorenebisphenol, 4,4'-biphenol, 3,3 ', 5,5'-tetramethyl-4,4'-dihydrate Oxybiphenyl, 2,2'-biphenol, resorcin, catechol, t-butylcatechol, t-butylhydroquinone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4 -Dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene , 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, the dihydroxy Bivalent phenols such as allylated or polyallylated naphthalene, allylated bisphenol A, allylated bisphenol F, allylated phenol novolac, or Phenol novolac, bisphenol A novolac, o-cresol novolak, m-cresol novolak, p-cresol novolak, xylenol novolak, poly-p-hydroxystyrene, tris- (4-hydroxyphenyl) methane , 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2, Halogenation, such as trivalent or more phenols, such as 4-benzene triol, 2,3, 4- trihydroxy benzophenone, a phenol aralkyl resin, a naphthol aralkyl resin, dicyclopentadiene type resin, or tetrabromobisphenol A, etc. Glycidyl ether derivatives derived from bisphenols. These other epoxy resins can be used 1 type or in mixture of 2 or more types.

Although the epoxy resin composition of this invention may contain the epoxy resin of another kind as long as the compounding ratio in the epoxy resin composition of the benzophenone type epoxy resin represented by General formula (1) is 50 wt% or more in an epoxy resin component, From the viewpoint of improving the thermal conductivity at the time of using, the total amount of the bifunctional epoxy resin is preferably 80 wt% or more, and more preferably 90 wt% or more.

As an epoxy resin other than the benzophenone epoxy resin, especially preferable epoxy resin is bisphenol-type epoxy resin represented by following General formula (3).

Wherein R ₁ to R ₃ represent a halogen atom, a hydrocarbon group of 1 to 8 carbon atoms, or an alkoxy group of 1 to 8 carbon atoms, m is a number of 0 to 5, X is a single bond, a methylene group, an oxygen atom, Pongi or sulfur atoms.)

The bisphenol epoxy resin is 4,4'-dihydroxybiphenyl, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, 4,4'-dihydroxydi Phenylmethane, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenylether, 4,4'-dihydroxydiphenyl It can synthesize | combine by performing normal epoxidation reaction using sulfide as a raw material. These epoxy resins can be synthesized using those mixed with 4,4'-dihydroxybenzophenone in the raw material step. Particularly preferred among them are epoxy resins synthesized from 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenylmethane and 4,4'-dihydroxydiphenyl ether, and excellent in handleability. The molded article which is excellent also in thermal conductivity while providing a crystalline epoxy resin can be provided.

The epoxy resin composition of this invention uses the benzophenone series phenolic resin represented by the said General formula (2) as an essential component as a hardening | curing agent. Here, as said benzophenone series phenolic resin, Preferably, m is 0 and 4,4'- dihydroxy benzophenone.

In addition, when applying the epoxy resin composition of this invention as a prepreg for laminated materials, in the said General formula (2), the number of benzophenone series phenolic resin whose number is larger than 0 is used suitably as an average value. The preferable value of m in this case is 1-15 as an average value, More preferably, it is 2-15. Moreover, although the manufacturing method of the benzophenone type phenolic resin which m number increased was not limited, For example, an excess of 4,4'- dihydroxy benzophenone is reacted with respect to the benzophenone type epoxy resin of the said General formula (1). The technique to make it work is mentioned. Or it can synthesize | combine by making 1 mol or less of epichlorohydrin react with 1 mol of hydroxyl groups in 4,4'- dihydroxy benzophenone and 4,4'- dihydroxy benzophenone.

The hydroxyl equivalent of the benzophenone-based phenolic resin represented by the general formula (2) is usually in the range of 100 to 20,000. Like the epoxy resin, a suitable hydroxyl equivalent is appropriately selected depending on the application. For example, in the use of a semiconductor encapsulation, it is preferable that it is low viscosity from the viewpoint of the high filling rate of an inorganic filler and the improvement of fluidity | liquidity, In the said General formula (2), the hydroxyl equivalent whose main component is m = 0 is 100-200 It is preferable that it is a range. Moreover, in use, such as a laminated board, it is the range of 200-20,000 preferably from a viewpoint of film property and flexibility provision. It is preferable to satisfy this also when this hydroxyl group equivalent uses two or more types of epoxy resins, and in this case, a hydroxyl group equivalent is computed in total weight (g) / hydroxyl group (mol).

As a hardening | curing agent used for the epoxy resin composition of this invention, what is generally known as an epoxy resin hardening | curing agent other than the benzophenone type phenolic resin represented by General formula (2) which is an essential component of this invention can be combined as needed. Preferably, another phenolic hardener which has a phenolic hydroxyl group is selected. Specific examples of other phenolic curing agents include bisphenol A, bisphenol F, 4,4'-dihydroxydiphenyl ether, 1,4-bis (4-hydroxyphenoxy) benzene, and 1,3-bis (4- Hydroxyphenoxy) benzene, 4,4'-dihydroxydiphenylsulfide, 4,4'-dihydroxydiphenylketone, 4,4'-dihydroxydiphenylsulfone, 4,4'-di Hydroxybiphenyl, 2,2'-dihydroxybiphenyl, 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, Bisphenol A novolac, o-cresol novolak, m-cresol novolak, p-cresol novolak, xylenol novolak, poly-p-hydroxystyrene, hydroquinone, resorcin, catechol, t-butylcatechol, t-butylhydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxy Benzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydrate Loxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2, 5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated or polyallylate of the dihydroxynaphthalene, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak, allylated pyrogallol, etc. are mentioned.

Although the epoxy resin composition of this invention may contain the other phenolic compound (resin) as the compounding ratio of the benzophenone series phenolic resin represented by General formula (2) is 50 wt% or more in a hardening | curing agent component, hardened | cured material From the standpoint of improving the thermal conductivity when used, the total amount of the bifunctional phenolic compound (resin) is preferably 80 wt% or more, more preferably 90 wt% or more.

As a phenolic compound (resin) other than benzophenone series phenolic resin, what is especially preferable is hydroquinone, 4,4'- dihydroxy biphenyl, 4,4'- dihydroxy diphenylmethane, 4, 4'-dihydroxydiphenylether, 1,4-bis (4-hydroxyphenoxy) benzene, 4,4'-dihydroxydiphenylsulfide, 1,5-naphthalenediol, 2,7-naphthalene Diol and 2, 6- naphthalenediol can be illustrated. The usage-amount of these bifunctional phenolic compounds or phenolic resin is 50 weight% or less in hardening | curing agent component, Preferably it is 20 weight% or less.

As a hardening | curing agent used for the epoxy resin composition of this invention, other hardening | curing agent generally known as a hardening | curing agent other than said phenolic hardening | curing agent can be used together and used. For example, an amine hardener, an acid anhydride hardener, a phenol type hardener, a polymercaptan type hardener, a polyaminoamide type hardener, an isocyanate type hardener, a block isocyanate type hardener, etc. are mentioned. What is necessary is just to set the compounding quantity of these hardening | curing agents suitably in consideration of the kind of hardening | curing agent mix | blended and the physical property of the heat conductive epoxy resin molded object obtained.

Specific examples of the amine curing agent include aliphatic amines, polyether polyamines, alicyclic amines, aromatic amines, and the like. Examples of the aliphatic amines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, Bis (hexamethylene) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethylethylenediamine, tetra (hydroxyethyl) ethylenediamine and the like. Examples of the polyether polyamines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis (propylamine), polyoxypropylene diamine, polyoxypropylene triamine, and the like. Examples of the alicyclic amines include isophoronediamine, metacenediamine, N-aminoethylpiperazine, bis (4-amino-3-methyldicyclohexyl) methane, bis (aminomethyl) cyclohexane, 3,9-bis (3- Aminopropyl) 2, 4, 8, 10- tetraoxaspiro (5, 5) undecane, norbornene diamine, etc. are mentioned. Examples of the aromatic amines are tetrachloro-p-xylenediamine, m-xylenediamine, p-xylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2, 4-toluenediamine, 2,4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 2,4-diaminodiphenyl Sulfone, 4,4'-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-dimethylaminomethyl) phenol, triethanolamine, methylbenzylamine, α- (m-aminophenyl ) Ethylamine, (alpha)-(p-aminophenyl) ethylamine, diamino diethyl dimethyl diphenylmethane, (alpha), (alpha) '-bis (4-aminophenyl) -p- diisopropyl benzene, etc. are mentioned.

Specific examples of the acid anhydride curing agent include dodecenyl succinic anhydride, polyadipic anhydride, polyazelanic anhydride, polycebacic anhydride, poly (ethyloctadecanoic acid) anhydride, poly (phenylhexadecanoic acid) anhydride, methyltetrahydro phthalic anhydride , Methyl hexahydro phthalic anhydride, hexahydro phthalic anhydride, methyl himic acid, tetrahydro phthalic anhydride, trialkyltetrahydro phthalic anhydride, methylcyclohexenedicarboxylic anhydride, methylcyclohexete tetracarboxylic anhydride, phthalic anhydride, trihydric anhydride Mellitic acid, pyromellitic anhydride, benzophenonetetracarboxylic acid anhydride, ethylene glycol bistrimellitate, hept anhydride, nadic acid anhydride, methylnadic acid anhydride, 5- (2,5-dioxotetrahydro-3-fura Nil) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid Water, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride, and the like.

In the epoxy resin composition of this invention, the compounding ratio of an epoxy resin and a hardening | curing agent is the range of 0.8-1.5 in an equivalence ratio of the functional group in an epoxy group and a hardening | curing agent. Outside of this range, since unreacted epoxy group or functional group in a hardening | curing agent remains after hardening, since reliability as an electrical insulation material falls, it is unpreferable.

You may add an inorganic filler to the epoxy resin composition of this invention. The amount of the inorganic filler added is 50 to 95 wt% with respect to the epoxy resin composition, preferably 80 to 95 wt%. When less than this, effects, such as high thermal conductivity, low thermal expansion property, and high heat resistance, are not fully exhibited. Although these effects are so good that the addition amount of an inorganic filler is large, it does not improve according to the volume fraction, but improves dramatically from a specific addition amount. These physical properties are due to the controlled effect of the higher order structure in the polymer state, and since the higher order structure is mainly achieved on the surface of the inorganic filler, it is considered that a specific amount of the inorganic filler is required. On the other hand, when the addition amount of an inorganic filler is larger than this, since a viscosity becomes high and moldability deteriorates, it is unpreferable.

The inorganic filler is preferably spherical, and is not particularly limited as long as it is spherical including an elliptic cross section, but it is particularly preferable that the inorganic filler be as close to a spherical form as possible from the viewpoint of fluidity improvement. Thereby, it is easy to take the closest packing structure, such as a face-centered cubic structure and a hexagonal dense structure, and sufficient filling amount can be obtained. If it is not spherical, it is not preferable because the amount of filling increases the friction between the fillers, the fluidity is extremely lowered before the upper limit is reached, the viscosity increases, and the moldability deteriorates.

From the viewpoint of thermal conductivity improvement, it is preferable to use 50 wt% or more of the inorganic filler whose thermal conductivity is 5 W / m * K or more among inorganic fillers, and alumina, aluminum nitride, crystalline silica, etc. are used suitably. Particularly preferred among these is spherical alumina. In addition, you may use together an amorphous inorganic filler, for example, fused silica, crystalline silica, etc. regardless of a shape as needed.

It is preferable that the average particle diameter of an inorganic filler is 30 micrometers or less. When the average particle diameter is larger than this, the fluidity of the epoxy resin composition is impaired and the strength is also lowered, which is not preferable.

The inorganic filler may be a combination of a fibrous substrate such as glass fiber or a fibrous substrate and a particulate inorganic filler. When compounding with a fibrous base material, it can be used as a varnish using a solvent, it can be made to impregnate the sheet-like fibrous base material, and it can be made to be the prepreg of this invention. The prepregs thus prepared are made of metal substrates such as copper foil, aluminum foil, stainless steel foil, polymer substrates such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, liquid crystal polymer, polyamide, polyimide, and Teflon (registered trademark). By laminating | stacking and heat-molding, it can apply as a printed wiring board, a heat radiation board | substrate, etc.

Conventionally well-known hardening accelerator can be used for the epoxy resin composition of this invention. For example, there are amines, imidazoles, organic phosphines, Lewis acids, and the like, specifically 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, triethanol Tertiary amines such as amine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecyl imida Organic phosphines such as imidazoles such as sol, tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium Tetra substituted phosphonium tetra substituted borate, such as ethyl triphenyl borate and tetrabutyl phosphonium tetrabutyl borate, 2-ethyl-4-methylimidazole tetraphenyl borate, N-methylmorpholine tetraphenyl borate, etc. Tetraphenyl boron salts; As addition amount, it is the range of 0.2-10 weight part with respect to 100 weight part of epoxy resins normally. These may be used independently and may be used together.

As for the addition amount of the said curing catalyst, 0.1-10.0 mass% is preferable with respect to the sum total of an epoxy resin (including the halogen containing epoxy resin as a flame retardant) and a hardening | curing agent. If it is less than 0.1 mass%, molding time becomes long, and workability | operativity is reduced by the rigidity fall at the time of shaping | molding, On the contrary, when it exceeds 10.0 mass%, hardening advances during molding and it is easy to generate unfilled.

In the epoxy resin composition of the present invention, wax can be used as a release agent generally used in the epoxy resin composition. As the wax, for example, stearic acid, montanic acid, montanic acid ester, phosphate ester or the like can be used.

In the epoxy resin composition of this invention, in order to improve the adhesive force of an inorganic filler and a resin component, the coupling agent generally used for an epoxy resin composition can be used. As a coupling agent, epoxysilane can be used, for example. As for the addition amount of a coupling agent, 0.1-2.0 mass% is preferable with respect to an epoxy resin composition. If it is less than 0.1 mass%, the matching of resin and a base material will not be good, and moldability will worsen, On the contrary, if it exceeds 2.0 mass%, the molded article contamination in continuous moldability will arise.

In addition, thermoplastic oligomers can be added to the epoxy resin composition of the present invention from the viewpoint of improving fluidity during molding and improving adhesion to substrates such as lead frames. Thermoplastic oligomers include C5 and C9 petroleum resins, styrene resins, indene resins, indene styrene copolymer resins, indene styrene phenol copolymer resins, indene coumarone copolymer resins, and indene benzothiophene copolymer resins. Is illustrated. As addition amount, it is the range of 2-30 weight part with respect to 100 weight part of epoxy resins normally.

Moreover, what is generally usable for an epoxy resin composition can be mix | blended suitably for the epoxy resin composition of this invention. For example, phosphorus flame retardants, flame retardants such as bromine compounds and antimony trioxide, and colorants such as carbon black and organic dyes can be used.

The epoxy resin composition of the present invention is prepared by uniformly mixing an epoxy resin, a curing agent, an inorganic filler, and other components other than the coupling agent with a mixer or the like, and then adding the coupling agent and mixing and kneading with a heating roll or kneader. . There is no restriction | limiting in particular in the compounding order of these components. It is also possible to grind the molten mixed dough after mixing the dough, to powder and to tablet. The epoxy resin composition of this invention has an epoxy resin and a hardening | curing agent as a main component of a resin component. Preferably at least 60 wt%, more preferably at least 80 wt% are epoxy resins and curing agents.

The epoxy resin composition of the present invention is useful as an electrical insulating material, and is particularly suitably used for sealing in semiconductor devices.

In order to obtain a molded article using the epoxy resin composition of the present invention, for example, a method such as transfer molding, press molding, mold molding, injection molding, extrusion molding or the like is applied, but from the viewpoint of mass productivity, transfer molding is preferable. At the time of this shaping | molding, heating is performed and hardening (polymerization) generate | occur | produces. Therefore, since the molded object obtained is a molded object of superposed | polymerized resin (thermoplastic or thermosetting resin), it is also called a hardened molding. In addition, hardening used in this specification is used by the meaning containing superposition | polymerization, and cured resin is used by the meaning containing a thermoplastic resin.

Although the molded article of the present invention is generally three-dimensionally crosslinked, it is not always necessary to be a three-dimensional crosslinked product, and may be a molded article made of a thermoplastic two-dimensional polymer. In particular, when a bifunctional epoxy resin is reacted with a bifunctional curing agent, a secondary hydroxyl group generated in the ring-opening reaction of an epoxy group is usually a three-dimensional crosslinked product by further reacting with an epoxy group, thereby selecting a curing condition to form a thermoplastic two-dimensional polymer molded body. Can be. It is preferable to use a crystalline molded article from the viewpoint of high thermal conductivity. Since a three-dimensional crosslinking point generally inhibits crystallinity, it is preferable to use a molded article mainly composed of two-dimensional polymers with less crosslinking. Expression of the crystallinity of the molded product can be confirmed by observation with the endothermic peak accompanying melting of the crystal as the melting point in the scanning differential thermal analysis. Usually, melting | fusing point range is 120 to 320 degreeC, Preferably it is the range of 150 to 300 degreeC, More preferably, it is the range of 200 to 280 degreeC.

The higher the crystallinity of the molded article of the present invention, the better. The degree of crystallization can be evaluated from the endothermic amount accompanying the melting of the crystal in the scanning differential thermal analysis. Usually, the endothermic amount is 5 J / g or more per unit weight of the resin component excluding the filler, and the preferred endothermic amount is 10 J / g or more. More preferably, it is 20 J / g or more, Especially preferably, it is 30 J / g or more. When smaller than this, the thermal conductivity improvement effect as an epoxy resin molding is small. Also, from the viewpoint of low thermal expansion and heat resistance improvement, higher crystallinity is preferable. In addition, the endothermic amount here refers to the endothermic amount obtained by measuring on the conditions of the temperature increase rate of 10 degree-C / min under nitrogen stream using the sample which measured about 10 mg accurately by the differential thermal analyzer.

Although the molded object of this invention can be obtained by heat-molding by the said shaping | molding method, Usually, although molding temperature is 80 degreeC-250 degreeC, in order to raise the crystallinity degree of a molded object, it is preferable to shape | mold at the temperature lower than melting | fusing point of a molded object. Preferred molding temperature is in the range of 100 ° C to 220 ° C, more preferably 150 ° C to 200 ° C. Moreover, preferable molding time is 30 second to 1 hour, More preferably, it is 1 to 30 minutes. In addition, the degree of crystallinity can be further increased by postcure after molding. Usually, the postcure temperature is from 130 ° C. to 250 ° C., and the time ranges from 1 hour to 20 hours, preferably from 5 ° C. to 40 ° C. below the endothermic peak temperature in the differential thermal analysis, from 1 hour to 24 hours. It is preferable to perform postcure over time. Moreover, the preferable thermal conductivity of a molded object is 4 W / m * K or more, Especially preferably, it is 6 W / m * K or more.

<Examples>

Hereinafter, the present invention will be described in more detail with reference to Examples.

(Reference Example 1)

1070 g of 4,4'-dihydroxydibenzophenone was dissolved in 6500 g of epichlorohydrin, and 808 g of a 48% aqueous sodium hydroxide solution was added dropwise at 60 DEG C under reduced pressure (about 130 Torr). In the meantime, the produced water was removed out of the system by azeotroping with epichlorohydrin, and the outflowed epichlorohydrin was returned to the system. After completion of the dropwise addition, the reaction was further continued for 1 hour, after which dehydration was carried out, epichlorohydrin was distilled off, 3500 g of methyl isobutyl ketones were added, and water washing was performed to remove salt. Thereafter, 100 g of 20% sodium hydroxide was added at 80 ° C, stirred for 2 hours, and washed with 1000 mL of warm water. Thereafter, water was removed by liquid separation, and methyl isobutyl ketone was distilled off under reduced pressure to obtain 1460 g of a pale yellow crystalline epoxy resin (epoxy resin A).

Melting | fusing point by the capillary method of epoxy resin A was 131 degreeC from 128 degreeC, and the viscosity in 150 degreeC was 11.6 mPa * s. The epoxy equivalent was 179, 270 ppm of hydrolyzable chlorine, and each component ratio in General formula (1) calculated | required from GPC measurement of obtained resin were n1.0 for 91.0% and n = 1 for 8.2%. Here, with hydrolyzable chlorine, 0.5 g of a sample was dissolved in 30 ml of dioxane, 10 ml of 1N-KOH was added thereto, and the mixture was refluxed for 30 minutes. After cooling to room temperature, 100 ml of 80% acetone water was further added. to a measured value by performing a potentiometric titration with 0.002N-AgNO ₃ aqueous solution. In addition, melting | fusing point is a value obtained at the temperature increase rate of 2 degree-C / min by the capillary method. Viscosity was measured by BROOKFIELD Co., Ltd., CAP2000H, and the softening point was measured by a round ball method according to JIS K-6911. GPC measurements also include devices; Nihon Waters, Form 515A, Column; TSK-GEL2000 × 3 and TSK-GEL4000 × 1 (both manufactured by Tosoh Corporation), solvents; Tetrahydrofuran, flow rate; 1 ml / min, temperature; 38 ° C., detector; In accordance with the terms of RI.

(Examples 1-6, Comparative Examples 1-5)

As the epoxy resin component, the epoxy resin (epoxy resin A) of Reference Example 1, the epoxide of 4,4'-dihydroxydiphenyl ether (epoxy resin B: manufactured by Toto Kasei Co., YSLV-80DE, epoxy equivalent weight 174) or 4,4'- dihydroxy dibenzophenone (curing agent A), 4,4 'using biphenyl type epoxy resin (Epoxy resin C: the Japan epoxy resin company, YX-4000H, epoxy equivalent 195), are used as a hardening | curing agent. -Dihydroxydiphenylether (curing agent B), 4,4'-dihydroxydiphenylmethane (curing agent C), 4,4'-dihydroxydibenzophenone (curing agent D) or phenol novolac (curing agent E : PSM-4261 from Group A, Kakuku Co., Ltd., OH equivalent 103, softening point of 82 ° C.) was used. Moreover, triphenylphosphine was used as a hardening accelerator, and spherical alumina (average particle diameter 12.2 micrometers) was used as an inorganic filler. After mix | blending the component shown in Table 1, and fully mixing with a mixer, the thing mix | blended and mixed for about 5 minutes with the heating roll was cooled, it grind | pulverized, and the epoxy resin composition of Examples 1-6 and Comparative Examples 1-5, respectively was obtained. Using this epoxy resin composition, molding and postcure were performed under the conditions shown in Table 1 to evaluate the physical properties of the molded product.

The results are collectively shown in Table 1 and Table 2. In addition, the number of each compound in a table | surface represents a weight part. In addition, evaluation was performed by the following.

(1) Thermal conductivity: It measured by the unsteady heat wire method using the LFA447 type | mold thermal conductivity meter by NETZSCH.

(2) Measurement of melting point and heat of melting (DSC method): It measured at the temperature increase rate of 10 degree-C / min using the differential scanning calorimetry apparatus (type DSC6200 by Seiko Instruments).

(3) Linear expansion coefficient and glass transition temperature: It measured at the temperature increase rate of 10 degree-C / min using the TMA120C type | mold thermometer measuring apparatus by Seiko Instruments.

(4) Absorption rate: The disk of diameter 50mm and thickness 3mm was shape | molded, and it was set as the weight change rate after moisture absorption for 100 hours on 85 degreeC and 85% of the relative humidity after postcure.

The epoxy resin composition of the present invention is excellent in formability and reliability, and gives a cured molded article excellent in high thermal conductivity, low water absorption, low thermal expansion, and high heat resistance, and is used for insulating materials for electrical and electronic parts such as semiconductor encapsulation, laminates, and heat dissipation substrates. It is suitably applied as an example, and excellent high heat dissipation property and dimensional stability are exhibited.

Claims (8)

In the epoxy resin composition comprising (A) an epoxy resin and (B) a curing agent, at least 50 wt% of the epoxy resin is represented by the following general formula (1),

(N represents the number of 0-15.)
A 4,4'-benzophenone-based epoxy resin represented by

(M shows the number of 0-15.)
An epoxy resin composition comprising 4,4'-benzophenone-based phenolic resins represented by the above formula, having an equivalence ratio between the epoxy group in the epoxy resin and the functional group in the curing agent in the range of 0.8 to 1.5. The method of claim 1,
An epoxy resin composition comprising 50 to 95 wt% of an inorganic filler. The method of claim 1,
Epoxy resin composition, characterized in that the epoxy resin composition for semiconductor encapsulation. A prepreg made by impregnating the epoxy resin composition according to claim 1 or 2 into a sheet-like fibrous base material in a semi-cured state. It is obtained by heat-molding the epoxy resin composition of any one of Claims 1-3, The molded object characterized by the above-mentioned. The method of claim 5,
A molded article characterized by a thermal conductivity of 4 W / m · K or more. The method of claim 5,
A molding characterized in that the peak of the melting point in the scanning differential thermal analysis is in the range of 150 ° C to 300 ° C. The method of claim 5,
A molded article characterized in that the endothermic amount of the resin component in terms of scanning differential thermal analysis is 5 J / g or more.