JP2011054769A - Adhesive for bonding electric element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive for bonding electric element with superior coating properties and storage stability, the adhesive preventing the increase of viscosity caused by addition of an imidazole compound. <P>SOLUTION: The adhesive for bonding electric element contains a curable compound, the imidazole compound and a polyvinyl phenol. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an adhesive for bonding electronic parts that is excellent in storage stability and excellent in applicability that can suppress an increase in viscosity due to the addition of an imidazole compound.

Conventionally, when a semiconductor product is manufactured using a semiconductor chip, a process (die bonding process) in which the semiconductor chip is bonded and fixed to a substrate or the like using an adhesive has been performed. In such a die bonding step, an epoxy adhesive in which a curing agent is blended with an epoxy resin is frequently used, and, for example, an imidazole compound is used as the curing agent.
As an epoxy-based adhesive using an imidazole compound, for example, Patent Document 1 discloses a die attach paste containing an epoxy resin, a phenol aralkyl resin, an imidazole compound, and the like. Patent Document 1 describes that the die attach paste described in the same document is excellent in adhesiveness, fast curability, and reliability, and that high adhesion reliability can be obtained by curing in a short time. In the Example of patent document 1, the adhesive strength at the time of making it harden | cure at 200 degreeC, 30 second, and 60 second is evaluated.

In recent years, there has been an increasing demand for higher integration of semiconductor packages, and semiconductor chips have been stacked in multiple layers. For this reason, using an adhesive that requires several tens of seconds for curing, such as the die attach paste described in Patent Document 1, there is a problem that the time required to manufacture one semiconductor package becomes longer. It was happening. In addition, due to the multi-layer stacking, a slight chip shift can be a fatal defect as a stacked body, but there is also a problem that a shift is likely to occur if it takes too much time for curing.

In order to eliminate the prolonged manufacturing time of the semiconductor package, for example, the use of a fast-curing adhesive has been studied.
However, in general, a fast-curing type adhesive uses a highly reactive curing agent, and thus has a problem of poor storage stability. For the purpose of enhancing the storage stability, the curing agent is used in a form to which latents such as various adducts and salts are given, but sufficient storage stability is not yet obtained. In addition, in the conventional adhesive, when an imidazole compound is added as a curing agent, the viscosity of the adhesive is increased more than necessary, and there is a problem that applicability is lowered.

JP 2004-172443 A

An object of this invention is to provide the adhesive for electronic component joining excellent in the storage stability and excellent in the applicability | paintability which can suppress the viscosity raise by addition of an imidazole compound.

The present invention is an electronic component bonding adhesive containing a curable compound, an imidazole compound, and polyvinylphenol.
The present invention is described in detail below.

The present inventors have found that adhesives for joining electronic parts containing a curable compound, an imidazole compound and polyvinylphenol are excellent in storage stability and can suppress an increase in viscosity due to the addition of an imidazole compound. The inventors have found that the present invention is superior and have completed the present invention.

The electronic component bonding adhesive of the present invention contains a curable compound.
Although the said curable compound is not specifically limited, It is preferable to contain an epoxy compound.
The epoxy compound is not particularly limited, and examples thereof include bisphenol type epoxy compounds such as bisphenol A type, bisphenol F type, bisphenol AD type, and bisphenol S type. In addition, a resorcinol-type epoxy compound is also preferable as the epoxy compound because the adhesive for bonding electronic parts can have a low viscosity. These epoxy compounds may be used independently and 2 or more types may be used together.

The curable compound may contain a reactive polymer compound having a functional group capable of reacting with the epoxy compound or the like (hereinafter also simply referred to as a reactive polymer compound).
By containing the reactive polymer compound, the bonding reliability of the adhesive for bonding electronic components when heat distortion occurs is improved.

The reactive polymer compound is not particularly limited, and examples thereof include a polymer compound having an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, an epoxy group, and the like. Among these, a polymer compound having an epoxy group is preferable.
By containing the polymer compound having the epoxy group, the cured product of the adhesive for bonding electronic parts exhibits excellent flexibility. Therefore, when both the epoxy compound and the polymer compound having an epoxy group are contained, the cured product of the adhesive for electronic component bonding has excellent mechanical strength, heat resistance and moisture resistance derived from the epoxy compound. And excellent flexibility derived from the above-mentioned polymer compound having an epoxy group, excellent thermal cycle resistance, solder reflow resistance, dimensional stability, etc., and high bonding reliability and connection reliability. Expresses sex.

The polymer compound having an epoxy group is not particularly limited as long as it is a polymer compound having an epoxy group at a terminal and / or side chain (pendant position). For example, an epoxy group-containing acrylic rubber, an epoxy group-containing butadiene rubber Bisphenol type high molecular weight epoxy resin, epoxy group-containing phenoxy resin, epoxy group-containing acrylic resin, epoxy group-containing urethane resin, epoxy group-containing polyester resin, and the like. Among these, an epoxy group-containing acrylic resin is preferable because it can contain a large amount of epoxy groups, and the mechanical strength and heat resistance of the cured product of the adhesive for bonding electronic parts are more excellent. These polymer compounds having an epoxy group may be used alone or in combination of two or more.

Moreover, it is preferable that the said sclerosing | hardenable compound contains an episulfide compound.
By containing the episulfide compound, the adhesive for bonding electronic parts is excellent in fast curing properties, and is cured very quickly once a curing reaction is initiated by an imidazole compound described later.

The episulfide compound is not particularly limited as long as it has an episulfide group, and examples thereof include compounds in which the oxygen atom of the epoxy group of the epoxy compound is substituted with a sulfur atom. Specifically, the episulfide compound is, for example, a bisphenol type episulfide compound (a compound in which the oxygen atom of the epoxy group of the bisphenol type epoxy compound is substituted with a sulfur atom), a hydrogenated bisphenol type episulfide compound, a dicyclopentadiene type episulfide compound, Biphenyl type episulfide compound, phenol novolak type episulfide compound, fluorene type episulfide compound, polyether modified episulfide compound, butadiene modified episulfide compound, triazine episulfide compound and the like can be mentioned. These episulfide compounds may be used independently and 2 or more types may be used together.
In the episulfide compound, at least some of the epoxy groups of the epoxy compound may be substituted with sulfur atoms, or all of the epoxy groups may be substituted with sulfur atoms.

Among the episulfide compounds, examples of commercially available products include YL-7007 (hydrogenated bisphenol A type episulfide compound) manufactured by Japan Epoxy Resin Co., Ltd.
The episulfide compound can be easily synthesized from an epoxy compound using a sulfurizing agent such as potassium thiocyanate or thiourea.

When the said curable compound contains the said episulfide compound, the compounding quantity of the said episulfide compound is not specifically limited, The preferable minimum which occupies for a total of 100 weight part of a curable compound is 5 weight part, A preferable upper limit is 70 weight part. . When the compounding amount of the episulfide compound is less than 5 parts by weight, the quick curability of the electronic component bonding adhesive may be lowered. When the compounding amount of the episulfide compound exceeds 70 parts by weight, the storage stability of the electronic component bonding adhesive may be lowered. As for the compounding quantity of the said episulfide compound, the more preferable minimum which occupies for a total of 100 weight part of a sclerosing | hardenable compound is 10 weight part, and a more preferable upper limit is 50 weight part.

The adhesive for joining electronic parts of the present invention contains an imidazole compound.
Since the said imidazole compound has high reactivity with the said sclerosing | hardenable compound, the adhesive agent for electronic component joining of this invention is excellent in quick curability by containing the said imidazole compound. In particular, since the imidazole compound is excellent in reactivity with the episulfide compound, when the episulfide compound is contained, the adhesive for bonding electronic parts further improves fast curability.

The imidazole compound is not particularly limited, but an epoxy adduct imidazole compound is preferable because the curing reaction starts at a relatively low temperature. In addition, in this specification, an epoxy adduct imidazole compound means the compound obtained by carrying out addition reaction of an epoxy compound to the secondary amine part of an imidazole compound.
The epoxy adduct imidazole compound is not particularly limited, and examples thereof include imidazole bisphenol type epoxy adduct compounds. The imidazole bisphenol-type epoxy adduct compound is not particularly limited, and examples thereof include a bisphenol A diglycidyl ether adduct of 2-methylimidazole and a bisphenol A diglycidyl ether adduct of 2-ethyl-4-methylimidazole.

Examples of the imidazole compound include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-n-propylimidazole, 2-undecyl-1H-imidazole, 2-heptadecyl-1H-imidazole, 1 , 2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-1H-imidazole, 4-methyl-2-phenyl-1H-imidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2- Methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl- -Ethyl-4-methylimidazolium trimellitate, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2 ' -Methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- (2'-undecylimidazolyl-)-ethyl-s-triazine, 2,4-diamino-6- [2 '-Ethyl-4-imidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxyme Ruimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenyl-4,5-di (2-cyanoethoxy) methylimidazole, 1-dodecyl-2-methyl-3-benzyl Imidazolium chloride, 1-benzyl-2-phenylimidazole hydrochloride, 1-benzyl-2-phenylimidazolium trimellitate, etc. may be used.

Although the compounding quantity of the said imidazole compound is not specifically limited, The preferable minimum with respect to 100 weight part of said curable compounds is 1 weight part, and a preferable upper limit is 20 weight part. When the compounding amount of the imidazole compound is less than 1 part by weight, the quick curability of the electronic component bonding adhesive may be lowered. When the compounding amount of the imidazole compound exceeds 20 parts by weight, the storage stability of the adhesive for bonding electronic parts may decrease, the viscosity may increase more than necessary, and the coating property may decrease. As for the compounding quantity of the said imidazole compound, the more preferable minimum with respect to 100 weight part of said curable compounds is 5 weight part, and a more preferable upper limit is 15 weight part.

The adhesive for joining electronic parts of the present invention contains polyvinylphenol.
Since the imidazole compound is highly reactive with the curable compound, an adhesive containing such an imidazole compound is generally excellent in rapid curability, but the storage stability is lowered. On the other hand, in the adhesive for bonding electronic parts of the present invention, the polyvinylphenol coordinates to the imidazole compound at room temperature, that is, the phenolic hydroxyl group of the polyvinylphenol forms a hydrogen bond with the imidazole compound. In addition, the imidazole compound is stabilized and the curing reaction hardly proceeds. On the other hand, when heated to a predetermined temperature or higher, the hydrogen bond due to the phenolic hydroxyl group of the polyvinylphenol is broken, the reactivity of the imidazole compound is increased, and the curing reaction proceeds.
Therefore, the adhesive for bonding electronic parts of the present invention is excellent in storage stability at room temperature, and on the other hand, it cures extremely fast when heated above a predetermined temperature, and the time required for manufacturing electronic parts (tact time) is remarkably shortened. can do.

Furthermore, generally, the said imidazole compound is a powder form, and the adhesive agent containing such an imidazole compound will raise a viscosity more than needed, and applicability | paintability will fall. On the other hand, in the adhesive for electronic component bonding of the present invention, the polyvinylphenol is coordinated to the imidazole compound to lower the surface of the highly polar imidazole compound, and the compatibility with the curable compound is improved. Since it increases, the increase in viscosity due to the addition of the imidazole compound is suppressed, and coatability is improved.
In addition, since the said polyvinyl phenol reacts with the said curable compounds, such as the said epoxy compound, when a hardening reaction advances by heating, it will be taken in into a hardening system, and it may have a bad influence on the hardened | cured material of the adhesive for electronic component joining. Absent.

Although the weight average molecular weight of the said polyvinylphenol is not specifically limited, A preferable minimum is 300 and a preferable upper limit is 10,000. When the weight average molecular weight is less than 300, polyvinyl phenol volatilizes when the curable compound is cured, and voids may be generated. When the weight average molecular weight exceeds 10,000, polyvinylphenol cannot be uniformly dispersed in the curable compound, and a desired effect by adding polyvinylphenol may not be obtained.
In addition, in this specification, the weight average molecular weight is a measuring device manufactured by Waters (column is “Shodex GPC LF-804” (length: 300 mm, 2 columns) manufactured by Showa Denko KK), measuring temperature is 40 ° C., flow rate is 1 mL / min, using tetrahydrofuran as a solvent and polystyrene as a standard substance) means a value obtained using polystyrene as a standard by gel permeation chromatography (GPC).

Although the compounding quantity of the said polyvinyl phenol is not specifically limited, The preferable minimum with respect to 100 weight part of said imidazole compounds is 10 weight part, and a preferable upper limit is 100 weight part. When the blending amount of the polyvinyl phenol is less than 10 parts by weight, the adhesive for bonding electronic parts may have a reduced storage stability, an excessive increase in viscosity, and a decrease in applicability. . When the blending amount of the polyvinylphenol exceeds 100 parts by weight, the curing speed of the adhesive for joining electronic components may be slow. As for the compounding quantity of the said polyvinylphenol, the more preferable minimum with respect to 100 weight part of said imidazole compounds is 20 weight part, and a more preferable upper limit is 70 weight part.

The adhesive for joining electronic parts of the present invention may contain other curing agents in addition to the imidazole compound as long as the effects of the present invention are not impaired.
The said other hardening | curing agent is not specifically limited, For example, a thiol compound, an acid anhydride, a phenol, etc. are mentioned. Of these, thiol compounds are preferred.
By containing the thiol compound, the adhesive for bonding electronic components is such that the curing reaction hardly proceeds while the polyvinylphenol is coordinated to the imidazole compound, and the coordination is removed and the reaction of the imidazole compound is performed. As the properties increase, the curing reaction proceeds very quickly. In general, various curing agents such as acid anhydrides are conceivable. However, by containing the thiol compound, the adhesive for bonding electronic parts further improves quick curability.

The thiol compound is not particularly limited as long as it has a thiol group, and examples thereof include an alkyl polythiol compound, a terminal thiol group-containing polyether, and a terminal thiol group-containing polythioether.
The alkyl polythiol compound is not particularly limited, and examples thereof include 1,4-butanedithiol, 1,6-hexanedithiol, 1,10-decanedithiol, triazinethiol and the like.

In addition, as the thiol compound, a thiol compound obtained by a reaction between an epoxy compound and hydrogen sulfide, a thiol compound having a terminal thiol group obtained by a reaction between a polythiol compound and an epoxy compound, bis (dicycloethyl) formal, and sodium polysulfide The thiol compound obtained by this reaction, etc., which uses a basic substance as a reaction catalyst in the production process, which is dealkalized to use a thiol compound etc. having an alkali metal ion concentration of 50 ppm or less Can do.

The acid anhydride is not particularly limited as long as it does not inhibit the effects of the present invention. For example, alicyclic acid anhydride, alkyl-substituted glutaric acid anhydride, aromatic acid anhydride, trialkyltetrahydrophthalic anhydride And succinic anhydride.
The alicyclic acid anhydride is not particularly limited. For example, polyazeline acid anhydride, methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, 5-norbornene-2, 3-dicarboxylic acid anhydride, norbornane-2,3-dicarboxylic acid anhydride, methyl-5-norbornene-2,3-dicarboxylic acid anhydride, methyl-norbornane-2,3-dicarboxylic acid anhydride, cyclohexane-1, Examples include 2,3-tricarboxylic acid-1,2 anhydride and cyclohexane-1,2,4-tricarboxylic acid-1,2 anhydride.

The alkyl-substituted glutaric anhydride is not particularly limited. For example, 3-alkyl glutaric anhydride having an optionally branched alkyl group having 1 to 8 carbon atoms such as 3-methylglutaric anhydride, 2- 2,3-dialkyl glutaric anhydride, 2,4-diethyl glutaric anhydride, 2,4 having an alkyl group having 1 to 8 carbon atoms which may be branched, such as ethyl-3-propyl glutaric anhydride -2,4-dialkyl glutaric acid anhydrides having an optionally branched alkyl group having 1 to 8 carbon atoms such as dimethyl glutaric acid anhydride.

The aromatic acid anhydride is not particularly limited, and examples thereof include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like.

When the adhesive for bonding electronic parts of the present invention contains the other curing agent, the compounding ratio of the imidazole compound and the other curing agent is not particularly limited as long as the effect of the present invention is not impaired. The preferable lower limit of the compounding amount of the imidazole compound relative to 1 part by weight of the other curing agent is 0.01 part by weight, and the preferable upper limit is 20 parts by weight. When the compounding amount of the imidazole compound is less than 0.01 parts by weight, the quick curability of the electronic component bonding adhesive may be lowered. When the compounding amount of the imidazole compound exceeds 20 parts by weight, the storage stability of the adhesive for bonding electronic parts may decrease, the viscosity may increase more than necessary, and the coating property may decrease. The more preferable lower limit of the compounding amount of the imidazole compound with respect to 1 part by weight of the other curing agent is 0.05 part by weight, and the more preferable upper limit is 15 parts by weight.

The adhesive for joining electronic components of the present invention preferably further contains a thixotropic agent. By containing the thixotropy-imparting agent, the adhesive for electronic component bonding can be adjusted so as to have an optimum viscosity behavior for bonding electronic components.
The thixotropy imparting agent is not particularly limited, and examples thereof include fine metal particles, calcium carbonate, fumed silica, inorganic fine particles such as aluminum oxide, boron nitride, aluminum nitride, and aluminum borate. Of these, fumed silica is preferable.

The thixotropy imparting agent may be subjected to a surface treatment as necessary. The thixotropy imparting agent subjected to the surface treatment is not particularly limited, but particles having a hydrophobic group on the surface are preferable. Examples of the particles having a hydrophobic group on the surface include fumed silica having a hydrophobic surface.

When the thixotropy-imparting agent is in the form of particles, the average particle size of the particulate thixotropy-imparting agent is not particularly limited, but a preferred upper limit is 1 μm. When the average particle diameter of the particulate thixotropy-imparting agent exceeds 1 μm, the adhesive for joining electronic components may not be able to express desired thixotropy.

When the electronic component bonding adhesive of the present invention contains the thixotropy imparting agent, the blending amount of the thixotropy imparting agent is not particularly limited, but the preferred lower limit in the electronic component bonding adhesive of the present invention is 0.5 weight. %, And a preferred upper limit is 20% by weight. If the blending amount of the thixotropy-imparting agent is less than 0.5% by weight, the thixotropy of the adhesive for joining electronic components may be insufficient. When the blending amount of the thixotropy-imparting agent exceeds 20% by weight, the detachability of the adhesive for joining electronic parts may be lowered when joining electronic parts such as semiconductor chips.

The adhesive for bonding electronic parts of the present invention may contain a solvent, if necessary.
The solvent is not particularly limited, and examples thereof include aromatic hydrocarbons, chlorinated aromatic hydrocarbons, chlorinated aliphatic hydrocarbons, alcohols, esters, ethers, ketones, glycol ethers (cellosolves), and fats. Examples thereof include cyclic hydrocarbons and aliphatic hydrocarbons.

The adhesive for bonding electronic parts of the present invention may contain an inorganic ion exchanger as necessary. Among the inorganic ion exchangers, examples of commercially available products include IXE series (manufactured by Toagosei Co., Ltd.).
Although the compounding quantity of the said inorganic ion exchanger is not specifically limited, The preferable minimum in the adhesive agent for electronic component joining of this invention is 1 weight%, and a preferable upper limit is 10 weight%.

The adhesive for joining electronic parts of the present invention may contain additives such as an anti-bleeding agent and an adhesion-imparting agent such as an imidazole silane coupling agent, if necessary.

In the adhesive for electronic component bonding of the present invention, an increase in viscosity due to the addition of the imidazole compound is suppressed by containing the polyvinyl phenol. The viscosity of the adhesive for bonding electronic parts of the present invention is not particularly limited, but the preferred lower limit of the viscosity measured with an E-type viscometer at 23 ° C. is 0.1 Pa · s, and the preferred upper limit is 100 Pa · s. When the viscosity is less than 0.1 Pa · s, the adhesive for bonding electronic components may sag during application. If the viscosity exceeds 100 Pa · s, the electronic component bonding adhesive may not be stably applied. In addition, as said E-type viscosity meter, for example, TOKI SANGYO CO. Examples include trade name “VISCOMETER TV-22” manufactured by LTD.

The method for producing the adhesive for bonding electronic parts of the present invention is not particularly limited. For example, the curable compound, the imidazole compound, the polyvinylphenol, and the other curing agent added as necessary, the thixotropy is imparted. A method of blending a predetermined amount of the agent, the solvent and the like and mixing them.
The mixing method is not particularly limited, and examples thereof include a method using a homodisper, a universal mixer, a Banbury mixer, a kneader and the like.

The adhesive for bonding electronic parts of the present invention is excellent in storage stability and suppresses an increase in viscosity due to the addition of an imidazole compound and is excellent in coating properties. For example, a semiconductor chip is bonded to a substrate or another semiconductor chip, etc. It is suitably used for joining electronic components.
In addition, the adhesive for bonding electronic parts of the present invention is also excellent in rapid curability, and specifically, curing can be completed by heating at about 150 to 200 ° C. for 1 to 10 seconds. It can be significantly shortened. Moreover, since the adhesive for electronic component joining of this invention can complete hardening at comparatively low temperature, when using for adhesion | attachment of a thin electronic component, the effect which suppresses generation | occurrence | production of curvature can also be exhibited. Furthermore, the adhesive for bonding electronic parts according to the present invention can complete the curing within 5 seconds when heating at about 240 to 260 ° C., which is the melting point region of the solder alloy for connection. It is also suitably used as an NCP used in flip chip connection of chips, lamination of semiconductor chips having through electrodes, and the like.
In the present specification, completion of curing means that adherends have a shear strength of 0.1 N / mm or more at room temperature.

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in storage stability and can provide the adhesive agent for electronic component joining excellent in the applicability | paintability which can suppress the viscosity raise by addition of an imidazole compound.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Examples 1-5, Comparative Examples 1-5)
According to the composition shown in Table 1, each material (parts by weight) shown below was stirred and mixed using a homodisper to prepare an adhesive for joining electronic components.

(1) Epoxy compound bisphenol A type epoxy compound (YL-980, manufactured by Japan Epoxy Resin Co., Ltd.)

(2) Episulfide compound hydrogenated bisphenol A type episulfide compound (YL-7007, manufactured by Japan Epoxy Resin Co., Ltd.)

(3) Imidazole compound epoxy adduct imidazole (P-0505, manufactured by Shikoku Chemicals)
Imidazolyl triazine (2MZA, manufactured by Shikoku Chemicals)
Imidazolyl triazine isocyanuric acid adduct (2MA-OK, manufactured by Shikoku Kasei Kogyo Co., Ltd.)

(4) Polyvinylphenol Polyvinylphenol (molecular weight 1100) (Marcalinker S1P, manufactured by Maruzen Petrochemical Co., Ltd.)

(5) Other additive silica filler (SE-4050-SPE, manufactured by Admatechs)

<Evaluation>
The following evaluation was performed about the adhesive agent for electronic component joining prepared in the Example and the comparative example. The results are shown in Table 1.

(1) Viscosity and storage stability Initially using an E-type viscometer (trade name “VISCOMETER TV-22”, manufactured by TOKI SANGYO CO. LTD, used rotor φ15 mm) at 23 ° C. The viscosity η ₀ (Pa · s) and the viscosity η _t (Pa · s) after 48 hours from the preparation were measured.
The case where the viscosity η _t did not reach twice the initial viscosity η ₀ was evaluated as “◯”, and the case where it reached 2 times as “×” was evaluated for storage stability.

(2) A 10 mL syringe (manufactured by Musashi Engineering Co., Ltd.) is filled with an adhesive for bonding electronic parts to be coated, a precision nozzle (manufactured by Musashi Engineering Co., Ltd., nozzle tip diameter 0.3 mm) is attached to the syringe tip, and a dispenser device (SHOT MASTER300 (manufactured by Musashi Engineering Co., Ltd.) was used to apply an electronic component bonding adhesive onto a glass substrate under conditions of a discharge pressure of 0.4 MPa, a gap between a semiconductor chip and a needle of 200 μm, and an average application amount of 5 mg. The applicability was evaluated as “◯” when the application variation was within ± 0.5 mg and “×” when the application variation was greater than ± 0.5 mg.

(3) Measurement of gelation time About 0.1 mL of an adhesive for bonding electronic parts is dropped on a glass substrate on a hot plate set at 150 ° C. and 200 ° C., and each temperature at 150 ° C. and 200 ° C. in advance. The glass warmed on the hot plate set to was pressed from above. The time until the pressed glass was not removed was measured as the gel time (seconds).

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in storage stability and can provide the adhesive agent for electronic component joining excellent in the applicability | paintability which can suppress the viscosity raise by addition of an imidazole compound.

Claims (3)

An adhesive for joining electronic parts, comprising a curable compound, an imidazole compound, and polyvinylphenol. The adhesive for bonding electronic parts according to claim 1, wherein the imidazole compound is an epoxy adduct imidazole compound. The adhesive for electronic component joining according to claim 1, wherein the curable compound contains an episulfide compound.