JPH10120761A - Epoxy resin composition, molding material for sealing, and electronic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition capable of giving cured products excellent in flexibility, toughness, adhesive properties and moisture proof reliability and suitable for molding materials for sealing of electronic parts by bringing the composition to contain a specific phenol resin, an epoxy resin and a curing agent as essential components. SOLUTION: This epoxy resin composition contains 100 pts.wt. of (A) an epoxy resin of bisphenol A type, etc., preferably 200-4000 pts.wt. of (B) a phenoxy resin having a structure expressed by the formula (R<1> and R<2> are each H or an alkyl; R<3> to R<10> are each H, a 1-4C alkyl or a halogen), a curing agent for the epoxy resin such as phenol (the amount to be used is preferably 0.7-1.2 equivalent aromatic hydroxyl groups based on 1 equivalent epoxy groups) and a curing agent for the phenoxy resin such as a block isocyanate (the amount to be added is preferably 0.05-0.4 in terms of the ratio of the equivalence of the isocyanate groups to the equivalence of the hydroxyl groups in the phenoxy resin as essential components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition used for an adhesive material, a molding material, a film material, etc., a molding material containing the same, and an IC sealed with the molding material. The present invention relates to an electronic component having elements such as a transistor and a capacitor.

[0002]

2. Description of the Related Art LCD televisions, word processors, personal computers, ICs
As electronic devices such as cards and electronic organizers have become smaller and thinner, there has been an increasing demand for smaller and thinner IC packages. To satisfy this demand, TCP (Tap
e Carrier Package), COB (Ch
ip on Board), COG (Chip on
Glass), MCM (Multi Chip Mod)
ule), etc., in the field of bare chip mounting, IC chips are sealed using a liquid sealing material.
As a driving IC for a D (liquid crystal display) panel, TCP using a liquid sealing material is mainly used. This TCP is LCD
It is expected that demand will increase sharply in the future along with the growth of and other related products. A major feature of TCP using a film tape as a base material is that it can be bent and mounted. In this case, tension acts on the sealing material when the tape is bent. Therefore, the sealing material is required to have flexibility (low elasticity), toughness, and high adhesiveness to a film tape, and low water absorption is also an important technical issue from the viewpoint of sealing reliability. ing.

[0003] As a sealing material, an epoxy resin generally excellent in electric characteristics, heat resistance, adhesiveness and the like is widely used. However, the cured product generally has a high modulus of elasticity, has a hard and brittle defect, and has reduced adhesiveness such as peel strength. For this reason, attempts have been made for a long time to modify the epoxy resin with a reactive elastomer to impart flexibility and toughness and to alleviate internal stress. on the other hand,
As another method of reducing internal stress, there is a method utilizing relaxation by a chain polymer such as a phenoxy resin. This phenoxy resin has a high molecular weight (typically 2000
(0 or more), and is classified as an independent and unique resin different from a low-molecular-weight (generally 5,000 or less) thermosetting epoxy resin (Plastic Handbook) , 49th
9-501 pages, published in 1986, published by Asakura Shoten). Journal of the Adhesion Society of Japan, Vol. 22, No. 5, 255-261 (198
6 years), bisphenol type epoxy resin (molecular weight 3
80, Epicoat 828 (trade name), it is shown that adding 50 to 70 parts by weight of a phenoxy resin to 100 parts by weight reduces the internal stress of the cured product. JP-A-61-228060 discloses an epoxy resin composition comprising an epoxy resin modified with a butadiene-acrylonitrile copolymer having a carboxyl group (prereaction), a phenoxy resin and a curing agent.
Japanese Patent Publication No. 7-30284 discloses a baking coating composition comprising a hydroxyl group-containing high molecular weight resin and a blocked isocyanate and having room temperature drying properties. In addition, Japanese Unexamined Patent Publication
JP-A-147618 discloses a resin composition using a liquid epoxy resin, a phenoxy resin, and a fine powder of blocked isocyanate and / or dicyandiamide as a curing agent.

[0004]

[Problems to be Solved by the Invention] Journal of the Adhesion Society of Japan No. 22
No. 5, pp. 255-261 (1986) and JP-A-61-228060 do not have a compound that reacts with a hydroxyl group in the phenoxy resin. When the molecular weight of the phenoxy resin is low or the composition contains a large amount of an inorganic filler, it becomes difficult to impart sufficient toughness to the cured product. Further, when a large amount of a thermoplastic phenoxy resin is contained, heat resistance is reduced. JP-A-2-
Japanese Patent No. 147618 discloses that a polymer obtained by reacting bisphenol A and epichlorohydrin is used as a phenoxy resin. However, sufficient adhesive strength (peeling strength) to a polyimide tape as a base material of TCP is described. I can't get it. Even the composition described in Japanese Patent Publication No. 7-30284 cannot provide a sufficient adhesive strength (peel strength) to a polyimide tape because it does not contain an epoxy resin having a low molecular weight (generally 5,000 or less). . Further, when a blocking agent such as a non-volatile epoxy resin curing agent is used for the blocked isocyanate, after the blocked isocyanate is dissociated, an unreacted blocking agent remains in the cured product, and water resistance, It is expected to adversely affect mechanical properties, adhesiveness, and the like.
Therefore, it is difficult to apply such a baking paint composition or a sealing adhesive as it is to a semiconductor field such as a liquid sealing material for TCP, and in various resin compositions, elasticity, toughness, adhesiveness, and moisture resistance are considered. It is a major challenge to design a material that satisfies the characteristics of the molding compound for sealing in terms of reliability.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems in the resin properties required as a liquid sealing material for TCP in the field of semiconductors, and as a result, have found that a specific structure has been obtained. It has been found that by using a phenoxy resin having a low elasticity, toughness, low water absorbability, and a cured product having excellent adhesion to an adherend, particularly a TCP film tape, can be obtained. Reached.

That is, the present invention relates to (A) an epoxy resin, (B) a phenoxy resin having the structure of the formula (I) in the molecular structure.

Embedded image (Where R ¹ and R ² are a hydrogen atom or an alkyl group, at least one of which is an alkyl group having 4 or more carbon atoms, and R ^{3 to} R ¹⁰
May be the same or different, and include a hydrogen atom, a carbon number of 1 to 4.
(C) a curing agent for an epoxy resin; and (D) a curing agent for a phenoxy resin. An epoxy resin composition containing the curing agent as an essential component, and a molding material for sealing containing the same. An electronic component having an element sealed with the molding material for sealing.

[0007]

DETAILED DESCRIPTION OF THE INVENTION (A) used in the present invention
As the epoxy resin of the component, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin,
Bisphenol AD epoxy resin, Bisphenol S
Type epoxy resins and their alkylene oxide adducts, halides, hydrogenated products, linear alkyl groups, branched alkyl groups, aryl groups, methylol groups, allyl groups, cyclic aliphatic groups on the aromatic rings of these phenol skeletons, Halogen, nitro group introduced, these bisphenol skeleton in the middle carbon atom straight chain alkyl group, branched alkyl group, allyl group, substituted allyl group, cycloaliphatic group, alkoxycarbonyl group Introduced, phenol novolak type epoxy resin, epoxidized novolak resin of phenols and aldehydes including o-cresol novolak type epoxy resin, diaminodiphenylmethane, metaxylenediamine, diaminomethylcyclohexane, isocyanuric acid, etc. Polyamine and epichlor Glycidylamine type epoxy resin obtained by reaction with drin, glycidyl ether type epoxy resin such as triphenyl glycidyl ether ethane, tetraphenyl glycidyl ether ethane, diglycidyl phthalate, diglycidyl tetrahydrophthalate, dihydrohexaphthalate Glycidyl ester, glycidyl ester type epoxy resin obtained by reaction of carboxylic acid and epichlorohydrin, including polyglycidyl ester of polymerized fatty acid, and cycloaliphatic epoxy that is epoxidized by oxidizing the double bond of cyclohexene ring with peracetic acid Resin, linear aliphatic epoxy resin obtained by oxidizing olefin bond with peracetic acid, etc.
YX-4000H (trade name) as a hydatoin-type epoxy resin having a glycidylation of a hydatoin ring such as diglycidyl hidatoin and glycidyl glycidoxyalkyl hidatoin, a polysulfide-modified epoxy resin having a polysulfide skeleton, and other special commercially available epoxy resins
(Biphenyl type epoxy resin, manufactured by Yuka Shell Co., Ltd.), trade names E-XL-3L, E-OCX-3L, SPI-DG
(Manufactured by Mitsui Toatsu), trade names EXA-7200, EXA-
4750, EXA-4700, HP-4032 (manufactured by Dainippon Ink and Chemicals), trade names EPPN-502, NC-700
0 (manufactured by Nippon Kayaku Co., Ltd.), trade names ESN-175, ESN-
375, ESLV-80XY, ESLV-90CR, E
SLV-120TE, ESLV-80DE (manufactured by Nippon Steel Chemical Co., Ltd.) and the like are used. Carboxyl group, amino group,
An elastomer-modified epoxy resin obtained by pre-reaction of an epoxy resin with various reactive elastomers such as a polybutadiene elastomer having a functional group such as a vinyl group can also be used. As these epoxy resins, those having a molecular weight of 5,000 or less are preferably used, and they can be used alone or in combination of two or more. The purity of the epoxy resin, particularly the amount of hydrolyzable chlorine, is preferably smaller because it is related to the corrosion of aluminum wiring on devices such as ICs. The total amount of chlorine is 1000 ppm or less, preferably 800 ppm or less, and the amount of hydrolyzable chlorine is 500 pp.
m or less, preferably 300 ppm or less is suitably used. Here, the amount of hydrolyzable chlorine means that 1 g of a sample epoxy resin is dissolved in 30 ml of dioxane, and 1N-KO is dissolved.
After adding 5 ml of H methanol solution and refluxing for 30 minutes, the value obtained by potentiometric titration was used as a scale.

The component (B) used in the present invention comprises:
A phenoxy resin having the structure of the formula (I) in the molecular structure.

Embedded image Here, R ¹ and R ² are a hydrogen atom or an alkyl group, at least one of which is an alkyl group having 4 or more carbon atoms, and R ^{3 to} R ^3
10 may be the same or different; a hydrogen atom;
4 represents an alkyl group and halogen. Specifically, R ¹ ,
R ² is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group,
4 or more carbon atoms such as decyl group, dodecyl group, isobutyl group, isopentyl group, isohexyl group, isoheptyl group, isooctyl group, isononyl group, isodecyl group, isododecyl group, neoheptyl group, neooctyl group, neononyl group, neodecyl group, neododecyl group, etc. R ^{3 to} R ¹⁰ are a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group,
An alkyl group such as a methylpropyl group, and a halogen such as a bromo group and a chloro group.

A phenoxy resin is a resin obtained by reacting a bifunctional phenol with epihalohydrin to a high molecular weight. For example, bifunctional phenols 1
Mol of epihalohydrin and 0.985 to 1.015 mol of epihalohydrin in a non-reactive solvent in the presence of an alkali metal hydroxide.
It is obtained by reacting at a temperature of 〜120 ° C. As epihalohydrin, epichlorohydrin, epibromohydrin, epiiodohydrin and the like can be used.
This phenoxy resin can also be obtained by a polyaddition reaction between a bifunctional epoxy resin and a bifunctional phenol. For example, the blending equivalent ratio of the bifunctional epoxy resin and the bifunctional phenol is determined as follows: epoxy group / phenol hydroxyl group = 1 /
0.9 to 1.1, having a boiling point of 1 in the presence of an alkali metal compound, an organic phosphorus compound, or a cyclic amine compound catalyst.
It can be obtained by heating at 50 to 200 ° C. in a amide-based, ketone-based, or alcohol-based solvent at a reaction solid concentration of 50% by weight or less at 50 to 200 ° C. to perform a polyaddition reaction. Such a phenoxy resin is preferable from the viewpoint of mechanical properties and thermal properties when used for a molding material for sealing.

Examples of the bifunctional epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, alkylene oxide adduct thereof, and halide thereof (tetrabromobisphenol type epoxy resin). Etc.), hydrogenated products, epoxidized bifunctional phenols of the formula (II) described below, furthermore, alicyclic epoxy resins, aliphatic chain epoxy resins, and halides and hydrogenated products thereof. These compounds may have any molecular weight. Particularly, when the compounds are reacted with a bifunctional phenol, those having as high a purity as possible are preferred. Some of these compounds can be used in combination.

The bifunctional phenols include phenols having a structure of the formula (II).

Embedded image Here, R ¹ and R ² are a hydrogen atom or an alkyl group, at least one of which is an alkyl group having 4 or more carbon atoms, and R ^{3 to} R ^3
10 may be the same or different; a hydrogen atom;
4 represents an alkyl group or halogen, specifically, the substituent described in the description of the formula (I). Such a bifunctional phenol having the structure of the formula (II) can be used alone or in combination. Further, any other compound having two phenolic hydroxyl groups may be used in combination, for example, hydroquinone,
Monocyclic bifunctional phenols such as 2-bromohydroquinone, resorcinol, catechol, bisphenol A,
Bisphenols such as bisphenol F, bisphenol AD and bisphenol S; dihydroxybiphenyls such as 4,4'-dihydroxybiphenyl;
Dihydroxyphenyl ethers such as hydroxyphenyl) ether, 1,4-naphthalenediol, 1,5
-Naphthalene diol, 1,6-naphthalene diol,
Examples include polycyclic bifunctional phenols such as naphthalene diols such as 1,7-naphthalene diol and 2,7-naphthalene diol. These bifunctional phenols other than the structure of the formula (II) can be introduced into the phenoxy resin skeleton by mixing and reacting with the phenol compound of the formula (II) during the synthesis of the phenoxy resin.

In the present invention, since the alkyl substituents of R ¹ and R ^{2 in} the formula (I) are considered to contribute to flexibility, hydrophobicity and adhesion, the curing required for the target electronic component is considered. The content of the structure of formula (I) can be adjusted arbitrarily according to the desired values of the flexibility, toughness and adhesive strength of the product. That is, when imparting more flexibility, the content of the structure of the formula (I) is increased, and when the substituent is a long-chain alkyl group, the content (molar number) is smaller than when the substituent is a short-chain alkyl group. ) Can provide flexibility. From the viewpoint of achieving the object of the present invention, the proportion of the component of the formula (I) in the phenoxy resin (B) is preferably from 10 to 90 mol%, more preferably from 20 to 80 mol%. If it is less than 10 mol%, sufficient flexibility and toughness may not be provided, and if it is more than 90 mol%, thermal properties such as glass transition temperature may be reduced. The content of the structure of the formula (I) can be adjusted by adjusting the amount of the phenol of the formula (II) and / or the epoxy resin obtained by epoxidizing the phenol of the formula (II).

The solution after the completion of the reaction can be purified by reprecipitation using a poor solvent such as methanol to obtain a solid phenoxy resin. The phenoxy resins thus produced can be used as a mixture of two or more. In order to show excellent properties such as flexibility, toughness, and film forming properties,
Average molecular weight (weight average molecular weight in terms of polystyrene by gel permeation chromatography) of 20,000
Above, preferably 30,000 or more phenoxy resins are used.

The amount of the phenoxy resin of the component (B) used in the present invention can be arbitrarily set according to the target values of flexibility, toughness and adhesive strength of the cured product required for the target electronic component. Is 70 to 96% by volume based on 100% by volume of the epoxy resin and the phenoxy resin in total.
And more preferably 75 to 94% by volume.
If it exceeds 96% by volume, the adhesiveness is reduced, and if it is less than 70% by volume, good mechanical properties (toughness, flexibility) of the phenoxy resin are not easily exhibited in the sealing material properties, which is not preferable. When the amount of the phenoxy resin is expressed in parts by weight, it depends on the specific gravity of the phenoxy resin and the specific gravity of the epoxy resin, but preferably 200 to 4000 parts by weight of the phenoxy resin with respect to 100 parts by weight of the epoxy resin (A).

If necessary, natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber,
Butyl rubber, ethylene-propylene rubber, chloroprene rubber, acrylonitrile-butadiene rubber, hydrogenated nitrile rubber, silicone rubber, acrylic rubber, epichlorohydrin rubber, fluorine rubber, polyolefin polyol, styrene-butadiene-methacrylate terpolymer A core-shell type rubber, a crosslinked rubber of a butadiene-acrylonitrile-butyl acrylate terpolymer, a styrene-based thermoplastic elastomer having a styrene-butadiene-styrene structure, and the like can also be added. These rubbers have epoxy groups, carboxyl groups, amino groups,
A functional group such as a vinyl group may be introduced. Also,
When dispersing and mixing these rubbers, it is preferable to disperse them in advance in a liquid epoxy resin or phenoxy resin solution by a kneading means such as a three-roll mill, a homomixer, or a grinder.

The curing agent for the epoxy resin (C) used in the present invention includes (1) phenol, cresol, xylenol, hydroquinone, resorcinol,
Catechol, phenols such as bisphenol A and bisphenol F or α-naphthol, β-naphthol,
Naphthols such as dihydroxynaphthalene and formaldehyde, acetaldehyde, propionaldehyde,
Resin obtained by condensing or co-condensing aldehydes such as benzaldehyde and salicylaldehyde in the presence of an acidic catalyst; phenol aralkyl resin having a xylylene skeleton synthesized from phenols and dimethoxyparaxylene; phenol having a dicyclopentadiene skeleton Resins; phenolic compounds such as naphthol resins having a xylylene skeleton; (2) phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, dodecyl Acid anhydrides such as succinic anhydride, (3) 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole Imidazole compounds such as 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, (4) diaminodiphenylmethane, Examples include amine compounds such as diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, and dicyandiamide; and (5) a polyamide resin synthesized from a dimer of linoleic acid and ethylenediamine. When used as a molding compound for stopping, the phenolic compound of the above (1) is particularly preferred from the viewpoint of excellent heat resistance and moisture resistance. The amount of the phenolic compound used is not particularly limited.
It is preferable from the viewpoint of heat resistance that the amount of the aromatic hydroxyl group be 0.7 to 1.2 equivalents.

The curing agent for the phenoxy resin (D) used in the present invention has two or more functional groups which react with the hydroxyl groups in the phenoxy resin in the molecular structure. When is used as a molding compound for sealing, a blocked isocyanate obtained by blocking an isocyanate group of an isocyanate compound with a blocking agent is preferable from the viewpoint of storage stability of the molding material for sealing.

The isocyanate compound in the blocked isocyanate is a compound having two or more isocyanate groups in the molecule, for example, toluene diisocyanate, isophorone diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, hexamethylene diisocyanate, trimethyl hexaisocyanate. Methylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, metaphenylene diisocyanate, hydrogenated metaphenylene diisocyanate, P-phenylene diisocyanate, tetramethyl xylene diisocyanate, triphenylmethane triisocyanate, tris (isocyanate phenyl) thiophosphate, 1,6 , 11-undecane triisocyanate, 1,8- Isocyanate-4-isocyanate methyl octane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate and isomers thereof, alkyl substitution products, such as halides. Further, a triisocyanate compound or a tetraisocyanate compound obtained by further introducing an isocyanate group into these diisocyanate compounds can also be used. These isocyanate compounds can be used alone or in combination of two or more.

The blocking agent for the blocked isocyanate is a compound containing an active hydrogen capable of reacting with an isocyanate group. Examples thereof include (1) phenol, cresol, xylenol, trimethylphenol, butylphenol, phenylphenol, naphthol, hydroquinone and resorcinol. , Catechol, bisphenol A,
Bisphenol F, bisphenol AD, 4,4′-biphenol, phenol novolak having an average of 2 to 5 nuclei,
Novolak resins such as ο-cresol novolak; naphthol resins; phenolic resins having a xylylene skeleton;
A phenolic resin having a dicyclopentadiene skeleton; a phenolic compound such as a naphthol resin having a xylylene skeleton; (2) butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, benzyl alcohol, ethanediol, propanediol; Methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, 2- (methoxymethoxy) ethanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether Alcohol compounds such as dipropylene glycol monomethyl ether and dipropylene glycol monoethyl ether , (3) dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, active methylene compounds such as acetylacetone, (4) acetanilide, acetic acid amide, .epsilon.-caprolactam, .delta.
Acid amide compounds such as valerolactam and γ-butyrolactam; (5) acid imide compounds such as succinimide and maleic imide; (6) imidazole, 2-methylimidazole, 2-ethylimidazole and 2-ethyl-
Imidazole compounds such as 4-methylimidazole and 2-phenylimidazole, (7) formaldoxime, acetoaldoxime, methylethylketoxime,
Oxime compounds such as methyl isobutyl ketoxime, methyl isoamyl ketoxime and cyclohexanone oxime; (8) amine compounds such as phenylnaphthylamine, diphenylamine, aniline and carbazole;
(9) Imine compounds such as ethyleneimine and polyethyleneimine. Of these, phenolic compounds, oxime compounds, alcohol compounds,
Lactam compounds are preferred.

The blocking reaction can be performed with or without the presence of a solvent. When a solvent is used, it is necessary to use a solvent inert to isocyanate groups. The blocking reaction can be generally performed at -20 to 150 ° C, but preferably at 0 to 100 ° C. If the temperature is too high, a side reaction may occur, and if the temperature is too low, the reaction rate decreases, which is disadvantageous. In addition, it is preferable to be blocked so that substantially no active isocyanate group is substantially eliminated. In the blocking reaction, an organic metal salt and a tertiary amine may be used as a catalyst.

The proportion of the isocyanate group equivalent to the hydroxyl equivalent of the phenoxy resin is 1 depending on the desired values of the flexibility, toughness and adhesive strength of the cured product required for the target electronic component. It can be blended so as to be as follows, but is preferably 0.05 to 0.6 in order to achieve both flexibility, high adhesiveness and heat resistance. More preferably, it is 0.05 to 0.4. If it is less than 0.05, the thermal characteristics may decrease due to a decrease in the degree of crosslinking of the phenoxy resin. If it exceeds 0.6, the degree of crosslinking may increase and the number of hydroxyl groups in the phenoxy resin may decrease, or the flexibility may decrease, so that the adhesiveness may decrease.

Further, a curing accelerator for epoxy resin and phenoxy resin can be used as required. Specifically, as curing accelerators for both resins, (1) diazabicycloalkenes such as 1,8-diazabicyclo (5,4,0) undecene-7 and derivatives thereof, triethylamine,
Tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; (2) 2-methylimidazole, 2-ethyl-4-
Methylimidazole, 2-phenylimidazole, 2-
Phenyl-4-methylimidazole, 2-heptadecylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-
Cyanoethyl-2-ethyl-4-methylimidazole,
Imidazoles such as 1-cyanoethyl-2-phenylimidazole; (3) organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine and phosphonium salts; and (4) tetraphenylphosphonium tetraphenyl. Tetraphenylboron salts such as borate, triphenylphosphinetetraphenylborate, 2-ethyl-4-methylimidazole / tetraphenylborate, and N-methylmorpholine / tetraphenylborate are used. Further, as a curing accelerator for the phenoxy resin, various types of zinc naphthenate, lead naphthenate, 2-ethylhexoate lead, 2-ethylhexoate cobalt, tin octoate, zinc octoate, antimony trioxide, etc. A metal compound or the like can be used. These curing agents and curing accelerators may be used alone or in combination of two or more.

The epoxy resin composition of the present invention may optionally contain an inorganic filler or an organic solvent.
Examples of the inorganic filler include powders such as fused silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate, magnesium carbonate, silicon carbide, boron nitride, beryllia, zirconia, and spherical beads of these, titanium One or more kinds of single crystal fibers such as potassium acid, silicon carbide, silicon nitride, and alumina, glass fibers, and the like can be blended. The amount of the inorganic filler can be arbitrarily determined depending on the characteristics, but is preferably 3 to the total solid content.
The content is preferably 0% by volume or more, and more preferably 50% by volume or more from the viewpoint of reducing the hygroscopicity, reducing the linear expansion coefficient and improving the strength. Furthermore, when imparting thixotropic property to the resin composition, a small amount of ultrafine silica or the like can be added in accordance with a desired thixotropic ratio.

As the organic solvent, an epoxy resin, a phenoxy resin, various curing agents and other additives can be dissolved, dispersed and mixed. Specifically, (1) N,
Amide solvents such as N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone, N-methylacetamide, formamide, (2) ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol Monoethyl ether acetate, ethylene glycol monobutyl ether acetate, dipropylene glycol methyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate Ether solvents such as diethylene glycol diacetate, (3) cyclohexanone, 2
-Methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2-octanone, 3-octanone, 4-octanone, 2-nonanone, 3-nonanone, 4-nonanone,
Ketone solvents such as 5-nonanone, (4) β-butyrolactone, γ-butyrolactone, β-valerolactone, δ
Lactone solvents such as valerolactone and γ-valerolactone; (5) alcohol solvents such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether; and ethylene glycol diacetate. And a solvent such as diethylene glycol diacetate can be used alone or in combination of two or more. When a blocked isocyanate is used, it is necessary to use a solvent that is inert to isocyanate groups, such as an amide solvent, an ether solvent, a ketone solvent, and a lactone solvent. The content of the solvent can be arbitrarily set according to the viscosity, the film thickness and the like of the molding material, but is generally 70% by volume or less, preferably 60% by volume or less based on the total volume. These solvents can be used as solvents at the time of synthesizing the phenoxy resin or the blocked isocyanate, and may be contained in the resin composition in the state of a reaction solution. Further, a low-boiling solvent that volatilizes quickly at normal temperature is not preferred because heating causes rapid volatilization of the solvent, causing voids and pinholes.

As other additives, it is preferable to use coupling agents such as isocyanate silane, epoxy silane, amino silane, ureido silane, vinyl silane, alkyl silane, mercapto silane, organic titanate and aluminum alcoholate. The method of using these coupling agents is not particularly limited, and may be used after treating the inorganic filler in advance. Further, it may be used by the integral blend method when other materials are blended. In addition, carbon black, titanium black pigment,
A coloring agent such as an organic dye, a flame retardant, and a flame retardant auxiliary (such as antimony trioxide) can be used as needed.

In the method of preparing the composition of the present invention, any method may be used as long as various materials can be uniformly dissolved and dispersed. As such a technique, for example, use of a device such as a grinder, a three-roll mill, a ball mill, a planetary mixer, a homomixer and the like can be mentioned.

As described above, the epoxy resin composition of the present invention comprises (A) an epoxy resin, (B) a phenoxy resin having the structure of the formula (I) in the molecular structure, and (C) a curing agent for the epoxy resin. , (D) a phenoxy resin curing agent as an essential component, a rubber component, an epoxy resin and / or
Alternatively, a phenoxy resin curing accelerator, an inorganic filler, an organic solvent, a coupling agent, a coloring agent, a flame retardant, an additive such as a flame retardant auxiliary can be added, and such an epoxy resin composition of the present invention can be used. It can be used as a molding material for encapsulating elements such as active elements such as semiconductor chips, transistors, diodes and thyristors, and passive elements such as capacitors, resistors and coils. When used as a molding compound for sealing, preferably (A) an epoxy resin, (B) a phenoxy resin having the structure of the formula (I) in the molecular structure,
(C) A curing agent for an epoxy resin and (D) a curing agent for a phenoxy resin are essential components, and a curing accelerator for an epoxy resin and / or a phenoxy resin, an inorganic filler, an organic solvent, and a coupling agent are added.

The elements such as the active element and the passive element described above are mounted on a support member such as a wired tape carrier, wiring board, glass, or silicon wafer, and necessary parts are sealed with the molding material of the present invention. Then, the electronic component can be manufactured. As such an electronic component, for example, there is a TCP in which a semiconductor chip connected to a tape carrier by a bump is sealed with the sealing molding material of the present invention. Active elements and / or capacitors such as semiconductor chips, transistors, diodes, and thyristors connected to wiring formed on a wiring board or glass by wire bonding, flip chip bonding, soldering, etc.
COB modules, hybrid ICs, in which passive elements such as resistors and coils are sealed with the sealing molding material of the present invention.
A multi-chip module can be used.

[0029]

EXAMPLES Next, examples of the present invention will be described, but the present invention is not limited to these examples.

Synthesis Example 1 A 500 mL four-necked flask equipped with a nitrogen inlet tube, a thermometer, a cooling tube and a mechanical stirrer was charged with 4,4 ′.
-(1-methyl-heptylidene) bisphenol (Bi
59.82 g of sP-OT, manufactured by Honshu Chemical Industry Co., Ltd., bisphenol A type epoxy resin (YD-8125, molecular distilled product, epoxy equivalent: 172 g / eq., manufactured by Toto Kasei Co., Ltd.) 6
5 g and N, N-dimethylacetamide 374.46 g
And stirred under a nitrogen atmosphere until uniform. Next, 0.3 g of lithium hydroxide was added and reacted at 120 ° C. for 4 hours while gradually increasing the temperature. For tracking the reaction, the viscosity of the reaction solution was measured at regular intervals, and the reaction was continued until the viscosity did not increase. After completion of the reaction, the reaction solution was allowed to cool, about 95 g of activated alumina (200 mesh) was added thereto, and the mixture was allowed to stand overnight. After filtering the activated alumina, the filtrate (reaction solution) was poured into a large amount of methanol to precipitate a solid resin, which was washed with methanol and dried under reduced pressure to obtain a desired phenoxy resin. The synthesized phenoxy resin is
Having the structure shown in formula (III),

Embedded image The hydroxyl equivalent in the resin was 319 (g / eq.), And gel permeation chromatography [column: TSKge
l G5000HXL + TSKgel G2000HX
L (trade name, manufactured by Tosoh Corporation), eluent: tetrahydrofuran, sample concentration: 0.5%], and the weight average molecular weight in terms of polystyrene is 45,000.

Comparative Synthesis Example 1 Tetrabromobisphenol A (FG-2000, manufactured by Teijin Chemicals Limited) 33 was placed in a 2 L four-necked flask equipped with a nitrogen inlet tube, a thermometer, a cooling tube, and a mechanical stirrer.
6.12 g, bisphenol A type epoxy resin (YD-
8125, molecular distilled product, epoxy equivalent 172g / e
q. 205.56 g and N, N-dimethylacetamide (1266 g) were added and mixed with stirring under a nitrogen atmosphere until uniform. Next, 0.93 g of lithium hydroxide was added, and the temperature was gradually increased to 120 ° C.
For 9 hours. For tracking the reaction, the viscosity of the reaction solution was measured at regular intervals, and the reaction was continued until the viscosity did not increase. After the completion of the reaction, the reaction solution was allowed to cool, and about 420 g of activated alumina (200 mesh) was added thereto and left overnight. Filtrate (reaction solution) after filtering activated alumina
Was poured into a large amount of methanol to precipitate a solid resin, which was washed with methanol and dried under reduced pressure to obtain a desired phenoxy resin. The synthesized brominated phenoxy resin has a structure represented by the formula (IV),

Embedded image The hydroxyl equivalent in the resin was 442 (g / eq.), Gel permeation chromatography [column: TSKge
l G5000HXL + TSKgel G2000HX
L (trade name of Tosoh Corporation), eluent: tetrahydrofuran,
The weight average molecular weight in terms of polystyrene determined by [sample concentration 0.5%] is 53,000.

Comparative Synthesis Example 2 In a 500 mL four-necked flask equipped with a nitrogen inlet tube, a thermometer, a cooling tube and a mechanical stirrer, 41.84 g of bisphenol A (manufactured by Tokyo Chemical Industry Co., Ltd.) and a bisphenol A type epoxy resin (YD- 8125, molecular distilled product, epoxy equivalent: 172 g / eq., Manufactured by Toto Kasei Co., Ltd.) and N, N-dimethylacetamide (305.52 g) were stirred and mixed under a nitrogen atmosphere until uniform. Next, 0.28 g of lithium hydroxide was added and reacted at 120 ° C. for 6 hours while gradually increasing the temperature. For tracking the reaction, the viscosity of the reaction solution was measured at regular intervals, and the reaction was continued until the viscosity did not increase. After completion of the reaction, the reaction solution was allowed to cool, and activated alumina (200 mesh) of about 7
8 g was added and left overnight. After filtering the activated alumina, the filtrate (reaction solution) was poured into a large amount of methanol to precipitate a solid resin, which was washed with methanol and dried under reduced pressure to obtain a desired phenoxy resin. The synthesized phenoxy resin is
Having the structure shown in formula (V),

Embedded image The hydroxyl equivalent in the resin was 284 (g / eq.), Gel permeation chromatography [column: TSKge
l G5000HXL + TSKgel G2000HX
L (trade name, manufactured by Tosoh Corporation), eluent: tetrahydrofuran, sample concentration 0.5%], and the weight average molecular weight in terms of polystyrene is 32,000.

Synthesis Example 2 [Synthesis of methyl ethyl ketoxime-blocked isocyanate] Metaphenylene diisocyanate (Millionate MT, Nippon Polyurethane Industry Co., Ltd.) 27.9 g and γ
78.8 g of butyrolactone is added, and the temperature is 55 ° C. in a nitrogen atmosphere.
While heating the mixture. Next, 20.4 g of methyl ethyl ketoxime was added dropwise over about 30 minutes.
For 5 hours. The block isocyanate / γ-butyrolactone solution thus obtained was used as it was. In addition, the isocyanate group equivalent of the obtained blocked isocyanate is 212 (g / eq.).

Example 1 An o-cresol novolak type epoxy resin (Y) was prepared such that the ratio of isocyanate group equivalent to hydroxyl group equivalent became 0.1.
DCN702S, epoxy equivalent 201 g / eq. 200 parts by weight of 100 parts by weight of γ-butyrolactone dissolved in 100 parts by weight of γ-butyrolactone, and 976 parts by weight of phenoxy resin (specific gravity 1.14) obtained in Synthesis Example 1 were mixed with γ-butyrolactone solution 2930 3906 parts by weight of a solution dissolved in parts by weight, phenol novolak resin (H-40)
0, hydroxyl equivalent 106 g / eq. , 53, manufactured by Meiwa Kaseisha)
Solution 1 obtained by dissolving parts by weight in 53 parts by weight of γ-butyrolactone
06 parts by weight, the blocked isocyanate obtained in Synthesis Example 2 /
172 parts by weight of γ-butyrolactone solution (block isocyanate content: 65 parts by weight), 4.7 parts by weight of 2-ethyl-4-methylimidazole / tetraphenylborate (EMZ-K, manufactured by Hokuko Chemical Co., Ltd.), fused silica (SE-8) 2840 parts by weight, γ-ureidopropyltriethoxysilane (AY43-031, manufactured by Toray Dow Corning Silicone Co., Ltd.) 4.5 parts by weight, isocyanatopropyltriethoxysilane (KBE-9007, Shin-Etsu Chemical Co., Ltd.) 14 parts by weight of an organic black dye (VA)
23 parts by weight of LIFAST BLACK 3820 (manufactured by Orient Chemical Industry Co., Ltd.) were mixed, and the mixture was stirred and mixed under reduced pressure for 25 minutes using a raikai machine (manufactured by Ishikawa Plant). The viscosity of the resin composition thus obtained is about 46 P (20 rpm)
Met. This was cast on a surface A of a 75 μm-thick polyimide film (UPILEX 75S, manufactured by Ube Industries, Ltd.) with a spacer of about 300 μm in thickness.
After heating for 0 minutes, the mixture was heated at 150 ° C. for 2 hours to obtain a cured product. The peel strength of the cured product from the polyimide film is 350 g / 25 mm width at room temperature and 500 g / 25 m at 120 ° C.
m width, and showed high adhesiveness in a wide temperature range. The cured product obtained had a flexural strength of 70 MPa and a flexural modulus of 10500 MPa, and had low elasticity while maintaining toughness. The glass transition temperature was 100 ° C. (measured viscoelasticity) and the coefficient of linear expansion was 2.3 × 10 ⁻⁵ / ° C. Furthermore, the water absorption of the cured product after 50 hours of the pressure cooker test (121 ° C., 2.1 atm) was as low as 0.1% by weight, and had low water absorption.

Comparative Example 1 333 parts by weight of a solution obtained by dissolving 100 parts by weight of the phenoxy resin obtained in Comparative Synthesis Example 1 in 233 parts by weight of γ-butyrolactone, and 12.6 parts by weight of the blocked isocyanate / γ-butyrolactone solution obtained in Synthesis Example 2 ( Blocked isocyanate content: 4.8 parts by weight), fused silica (SE-8, manufactured by Tokuyama Corporation): 249 parts by weight, isocyanatopropyltriethoxysilane (KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.)
1.6 parts by weight and an organic black dye (VALIFAST)
BLACK3820, manufactured by Orient Chemical Industries) 2.1
Parts by weight were blended, and stirred and mixed under reduced pressure for 25 minutes using a raii machine (manufactured by Ishikawa Plant). The resin composition containing no low-molecular-weight epoxy resin is cast on a surface A of a 75-μm-thick polyimide film (UPILEX 75S, manufactured by Ube Industries) with a spacer of about 300 μm in thickness,
After heating at 90 ° C. for 20 minutes, it was heated at 150 ° C. for 2 hours to obtain a cured product. The peel strength of the cured product from the polyimide film was 30 g / 25 mm width at room temperature, and had little adhesion.

Comparative Example 2 A bisphenol A type epoxy resin (YD-81) was prepared such that the ratio of isocyanate group equivalent to hydroxyl group equivalent became 0.1.
25, epoxy group equivalent 172 g / eq. 5. 100 parts by weight of Tohoku Kasei Co., Ltd.), 200 parts by weight of a solution obtained by dissolving 50 parts by weight of the phenoxy resin obtained in Comparative Synthesis Example 2 in 150 parts by weight of γ-butyrolactone, and the blocked isocyanate / γ-butyrolactone solution obtained in Synthesis Example 2. 124 parts by weight of a solution prepared by dissolving 3 parts by weight (block isocyanate content: 2.4 parts by weight) and 62 parts by weight of a phenol novolak resin (H-400, hydroxyl equivalent: 106 g / eq., Manufactured by Meiwa Kasei Co., Ltd.) in 62 parts by weight of γ-butyrolactone , 2-ethyl-4-methylimidazole tetraphenylborate (EMZ-K,
3 parts by weight, manufactured by Hokuko Chemical Co., Ltd., 510 parts by weight of fused silica (SE-8, manufactured by Tokuyama), 2.9 parts by weight of γ-ureidopropyltriethoxysilane (AY43-031, manufactured by Dow Corning Toray Silicone Co., Ltd.) 0.5 part by weight of isocyanatepropyltriethoxysilane (KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) and an organic black dye (VALI)
FAST BLACK 3820 (manufactured by Orient Chemical Industry Co., Ltd.) (4.3 parts by weight) was blended, and the mixture was stirred and mixed under reduced pressure for 25 minutes using a raikai machine (manufactured by Ishikawa Plant). This resin composition was coated with a spacer 7 having a thickness of about 300 μm.
5 μm polyimide film (UPILEX 75S,
The mixture was cast on side A of Ube Industries, Ltd.), heated at 90 ° C. for 20 minutes, and then heated at 150 ° C. for 2 hours to obtain a cured product. The peel strength of the cured product from the polyimide film was 100 g /
25 mm, and did not have sufficient adhesiveness. Further, the obtained cured product had a bending strength of 75 MPa and a flexural modulus of 13500 MPa, and was a hard and brittle cured product.

In order to clarify the above effects, an evaluation using an IC was performed. IC used for evaluation is about 2 × 10m
m is a tape carrier on which an element of m is mounted.
The resin compositions obtained in Comparative Examples 1 and 2 were applied as shown in FIG. 1 and cured at 150 ° C. for 2 hours.
The reliability of moisture resistance was examined by leaving the device in an atmosphere of 121 ° C./2 atm and checking for any disconnection due to aluminum wiring corrosion on the device. Table 1 shows the results. In Example 1 using a phenoxy resin having a long-chain alkyl group, ie, a hexyl group in the molecular structure, as a base resin, high adhesive performance was obtained as compared with a comparative example using a phenoxy resin having no long-chain alkyl group. And had excellent moisture resistance. Further, in Comparative Example 1 having no low molecular weight epoxy resin, the adhesiveness and the moisture resistance were remarkably inferior. In FIG. 1, 1 is a cured product of a resin composition, 2 is a semiconductor chip, 3 is polyimide, 4 is a bump, 5 is a tape carrier, and 6 is a lead.

[0038]

Table 1 Table 1 Evaluation items Example 1 Comparative example 1 Comparative example 2 ─────────────────────────── Peel strength (g / 25mm) Room temperature 350 30 100 120 ° C 500 ― ― Appearance Excellent Excellent Bendability ^{( 1)} Inferior inferior Moisture resistance ⁽²⁾ 450h 50h or less 100h ────────────────────────────── ⁽¹⁾ Observe the state of the cured product when bent nearly 180 degrees. Excellent: no crack, poor: crack or break ⁽²⁾ Time of occurrence of disconnection failure

[0039]

The epoxy resin composition of the present invention is capable of providing a cured product having excellent flexibility, toughness, adhesiveness, and moisture resistance reliability. Adhesive materials, sealing adhesive materials, etc.), molding materials, film materials, and the like. Particularly, when used for a molding compound for sealing represented by a liquid sealing material for TCP, excellent performance can be exhibited.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of TCP using a resin composition of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cured resin composition 2 ... Semiconductor chip 3 ... Polyimide 4 ... Bump 5 ... Tape carrier 6 ... Lead

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 23/29 H01L 23/30 R 23/31

Claims (3)

[Claims] (A) an epoxy resin; (B) a phenoxy resin having the structure of the formula (I) in the molecular structure. (Where R ¹ and R ² are a hydrogen atom or an alkyl group, at least one of which is an alkyl group having 4 or more carbon atoms, and R ^{3 to} R ¹⁰
May be the same or different, and include a hydrogen atom, a carbon number of 1 to 4.
(C) a curing agent for an epoxy resin; and (D) a curing agent for a phenoxy resin. 2. A molding compound for sealing comprising the epoxy resin composition according to claim 1. 3. An electronic component having an element sealed with the molding material for sealing according to claim 2.