JP2002275445A - Adhesive for printed circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive for a printed circuit, capable of exhibiting further excellent heat resistance, adhering property, processing property, etc., comparing with conventional epoxy resin-based adhesive. SOLUTION: This adhesive for the printed circuit is characterized by consisting of (A) a methoxy group-containing silane-modified epoxy resin obtained by performing a de-alcohol reaction of (1) a bisphenol type epoxy resin with (2) a methoxysilane partially condensed material, (B) a synthetic rubber, (C) a curing agent for an epoxy resin, (D) a sol-gel curing accelerator and (E) a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an adhesive for printed wiring boards. In particular, the present invention relates to an adhesive composition suitable for an adhesive composition for a flexible printed board and a tape for mounting a semiconductor integrated circuit called a TAB (tape automated bonding) method (hereinafter, abbreviated as “TAB tape”). The adhesive for printed wiring boards of the present invention is particularly excellent in adhesiveness, heat resistance and workability.

[0002]

2. Description of the Related Art In general, a flexible printed wiring board is formed by bonding a conductor such as a copper foil to a heat-resistant organic insulating film made of polyimide or the like having excellent heat resistance and electrical insulation properties via an adhesive. However, an epoxy resin adhesive is used as the adhesive from the viewpoint of high adhesiveness. However, recently, with the remarkable increase in wiring density and mounting density, there is a demand for further improvement in heat resistance and adhesiveness of epoxy resin-based adhesives due to heat generated from wiring locations and mounted components. The TAB tape is basically the same as a flexible printed wiring board,
Although the material composition and various required characteristics are basically common, both are used properly according to the required characteristic level at present.

[0003] Further, when dissimilar materials are bonded using an epoxy resin-based adhesive, a large distortion is generated in the adhesive layer due to thermal cycling, and the joint may be broken. Attempts have been made to make the adhesive flexible by absorbing such internal strain and preventing the generation of internal stress.
For example, Japanese Patent Application Laid-Open No. H10-335768 discloses a method of adding a synthetic rubber or the like to an adhesive. The adhesive obtained by adding a synthetic rubber to an epoxy resin has excellent peel strength, but has a high heat resistance. Not satisfactory.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a print which can exhibit more excellent heat resistance, adhesiveness, workability and the like as compared with a conventional epoxy resin adhesive which is an adhesive for printed wiring boards. An object of the present invention is to provide an adhesive for a wiring board.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have obtained a methoxy group-containing silane-modified epoxy resin obtained by modifying a specific epoxy resin with a specific methoxysilane compound. By using a resin composition as an essential component, it has been found that an adhesive for printed wiring boards meeting the above-mentioned object can be obtained, and the present invention has been completed.

That is, the present invention provides a methoxy group-containing silane-modified epoxy resin (A), a synthetic rubber (B) obtained by subjecting a bisphenol-type epoxy resin (1) and a methoxysilane partial condensate (2) to a dealcoholization reaction. The present invention relates to an adhesive for printed wiring boards, comprising an epoxy resin curing agent (C), a sol-gel curing accelerator (D) and a solvent (E). The present invention also relates to an adhesive for a flexible printed wiring board and an adhesive for a tape automated bonding tape.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, a methoxy group-containing silane-modified epoxy resin (A) used in the present invention comprises a bisphenol-type epoxy resin (1) and a methoxysilane partial condensate (2). The bisphenol type epoxy resin (1) is obtained by reacting a bisphenol with a haloepoxide such as epichlorohydrin or β-methylepichlorohydrin. Examples of bisphenols include a reaction product of phenol or 2,6-dihalophenol with an aldehyde or ketone such as formaldehyde, acetaldehyde, acetone, acetophenone, cyclohexanone, and benzophenone;
Examples include those obtained by oxidation of dihydroxyphenyl sulfide with a peracid, etherification reaction between hydroquinones, and the like.

Further, the bisphenol type epoxy resin (1) has a hydroxyl group capable of undergoing a dealcoholization reaction with the methoxysilane partial condensate (2). The hydroxyl group does not need to be contained in all molecules constituting the bisphenol-type epoxy resin (1), and it is sufficient that the bisphenol-type epoxy resin (1) has a hydroxyl group. Since the epoxy equivalent of the bisphenol-type epoxy resin (1) varies depending on the structure of the bisphenol-type epoxy resin (1), an epoxy equivalent having an appropriate epoxy equivalent can be appropriately selected and used depending on the application.
Those having g / eq or less are preferable. 350g / eq
If it is less than 1, the adhesiveness of the obtained adhesive layer at high temperatures tends to decrease, and if it exceeds 1000 g / eq, the storage stability of the methoxy group-containing silane-modified epoxy resin tends to decrease. Among these bisphenol-type epoxy resins (1), bisphenol A-type epoxy resins are particularly most commonly used and are inexpensive and preferable.

As the methoxysilane partial condensate (2) constituting the methoxy-containing silane-modified epoxy resin (A), methoxysilane generally used in the sol-gel method is partially hydrolyzed and condensed. Oligomers can be used. For example, the general formula: R _p Si (OCH ₃ )
_4-p (where p represents an integer of 0 or 1 and R represents a lower alkyl group or a phenyl group having 6 or less carbon atoms), and a partial condensate of the compound represented by _4-p and the like can be exemplified. Note that p
Is 2 to 4, three-dimensional crosslinking does not occur, and thus the desired high heat resistance cannot be imparted to the finally obtained adhesive for printed wiring boards.

Specific examples of the methoxysilane partial condensate (2) include partial condensates of tetramethoxysilane; methyltrimethoxysilane, ethyltrimethoxysilane,
and partial condensates of trimethoxysilanes such as n-propyltrimethoxysilane, isopropyltrimethoxysilane, vinyltrimethoxysilane, and phenyltrimethoxysilane. Among these, a partial condensate such as tetramethoxysilane or methyltrimethoxysilane is preferable as the adhesive for printed circuit boards because of its high sol-gel curing rate.

As the methoxysilane partial condensate (2), one or more of the above substances may be appropriately selected, but the average number of Si per molecule is preferably 3 to 12. If the average number of Si is less than 3, the amount of toxic methoxysilanes flowing out of the system together with the by-product alcohol during the dealcoholization reaction with the bisphenol-type epoxy resin (1) is not preferred. Also one
If it exceeds 2, the reactivity with the bisphenol-type epoxy resin (1) decreases, and it takes a long time to obtain the desired methoxy group-containing silane-modified epoxy resin (A).

In particular, the general formula:

[0013]

Embedded image

(In the formula, Me represents a methyl group, and the average number of repeating units of n is 2 to 7.) A partial condensate of tetramethoxysilane represented by the following formula: The partial condensate has almost no toxic tetramethoxysilane that can flow out of the system together with the by-product methanol in the demethanol reaction, and is preferable from the viewpoint of reaction operation and safety and health.

The methoxy group-containing silane-modified epoxy resin (A) used in the present invention is obtained by a dealcoholation reaction between the bisphenol type epoxy resin (1) and the methoxysilane partial condensate (2). The usage ratio of the bisphenol type epoxy resin (1) and the methoxysilane partial condensate (2) is not particularly limited as long as the methoxy group remains in the obtained methoxy group-containing silane-modified epoxy resin (A). However, it is preferable that the weight (weight ratio) of the methoxysilane partial condensate (2) in terms of silica / the weight of the bisphenol-type epoxy resin (1) is in the range of 0.25 to 1.2. Here, the silica equivalent weight of the methoxysilane partial condensate (2) is the weight when the methoxysilane partial condensate (2) is cured to silica by a sol-gel reaction.

In the production of the methoxy group-containing silane-modified epoxy resin (A), for example, a bisphenol type epoxy resin (1) and a methoxysilane partial condensate (2) are charged and heated to distill off by-produced alcohol. It is carried out by refluxing in a cooling pipe and returning the system. The reaction temperature is about 50 to 130 ° C, preferably 70 to 110 ° C, and the total reaction time is about 1 to 15 hours. This reaction is preferably performed under substantially anhydrous conditions in order to prevent a polycondensation reaction of the methoxysilane partial condensate (2) itself.

In the above-mentioned dealcoholization reaction, among the conventionally known catalysts for promoting the reaction, those which do not open the epoxy ring can be used. Examples of the catalyst include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, barium, strontium, zinc, aluminum, titanium,
Cobalt, germanium, tin, lead, antimony, arsenic,
Metals such as cerium, boron, cadmium, manganese;
Examples thereof include oxides, organic acid salts, halides, and methoxides of these metals. Among them, organic tin and organic acid tin are particularly preferable, and specifically, dibutyltin dilaurate, tin octylate and the like are effective.

The above reaction can be carried out with or without a solvent. The solvent is not particularly limited as long as it is an organic solvent that dissolves the bisphenol-type epoxy resin (1) and the methoxysilane partial condensate (2) and is inactive against these. Examples of such an organic solvent include ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone; esters such as ethyl acetate and butyl acetate; aromatics such as toluene and xylene; cellosolve acetate; methyl cellosolve acetate; , Alcohols such as isopropyl alcohol and n-butyl alcohol, and aprotic polar solvents such as dimethylformamide. Among them, those having a boiling point of 70 to 110 ° C. at normal pressure, such as methyl ethyl ketone, are particularly preferable for the following reasons. That is, when using the adhesive for a printed wiring board, a B-stage layer (a semi-cured layer of the present adhesive) is formed on a heat-resistant organic insulating film such as polyimide, and a conductor such as a copper foil is hot-pressed. It goes through a manufacturing process of forming a C-stage layer (completely cured layer of the present adhesive) by further heating. However, when a large amount of volatile matter (solvent, etc.) is generated during heating after bonding the conductor, the conductor and the adhesive This is because air bubbles are generated between the conductive layer and the layer, causing problems such as unevenness on the conductor surface. for that reason,
When the B-stage layer is formed, it is preferable to reduce the residual amount of volatile components such as a solvent as much as possible and to adjust the residual ratio of volatile components in the cured residue of the C-stage layer to 5% by weight or less. When a solvent having a boiling point higher than 110 ° C. is used, it is necessary to excessively raise the formation temperature of the B-stage layer in order to lower the residual ratio of the solvent. It is not preferable because the property becomes insufficient. When the boiling point of the solvent used is lower than 70 ° C., it is not preferable because the alcohol removal reaction between the bisphenol-type epoxy resin (1) and the methoxysilane partial condensate (2) requires a long time.

The methoxy group-containing silane-modified epoxy resin (A) thus obtained contains, as a main component, an epoxy resin in which the hydroxyl group in the bisphenol type epoxy resin (1) is silane-modified. The epoxy resin (A) may contain an unreacted bisphenol-type epoxy resin (1) or an unreacted methoxysilane partial condensate (2).

The methoxy group-containing silane-modified epoxy resin (A) has in its molecule a methoxysilyl moiety derived from a methoxysilane partial condensate (2) and an epoxy group derived from a bisphenol-type epoxy resin. The methoxysilyl moiety forms a mutually bonded cured product by evaporation or heat treatment of the solvent or by reaction with water (moisture). Such a cured product has a gelled fine silica site (high-order network structure of siloxane bonds). Therefore, the methoxy group contained in the methoxy group-containing silane-modified epoxy resin (A) accounts for 60 mol% of the methoxyl group of the methoxysilane partial condensate (2) used.
It is preferable to hold the above. The epoxy group reacts with the epoxy resin curing agent (C).

The synthetic rubber (B) used in the present invention includes:
What is necessary is just to be able to give a moderate flexibility to the obtained adhesive for printed wiring boards. For example, polyisobutene,
Examples thereof include butadiene rubber, styrene-butadiene rubber, nitrile rubber, and chloroprene rubber. Considering the interlayer adhesion between the cured adhesive layer and the conductor and the electrical characteristics of the cured adhesive layer, nitrile rubber (hereinafter referred to as NBR) is used. ) Or NBR containing a carboxyl group at the molecular end. The blending ratio of the synthetic rubber (B) is not particularly limited, but from the viewpoint of interlayer adhesion between the cured adhesive layer and the conductor, based on 100 parts by weight of the cured residue of the methoxy group-containing silane-modified epoxy resin (A). It is preferably 30 to 100 parts by weight. If the mixing ratio is less than 30 parts by weight, the adhesion of the cured layer to the conductor will be insufficient, and if it exceeds 100 parts by weight, the heat resistance tends to decrease. The cured residue of the methoxy group-containing silane-modified epoxy resin (A) is determined as follows. That is, a methoxy group-containing silane-modified epoxy resin (A) and an equivalent amount of triethylenetetramine are mixed, and about 1 g of the mixed solution is weighed and measured in an aluminum cup (50 mm diameter), and this is weighed at 100 ° C. for 1 hour. ,
Subsequently, it is dried and cured at 200 ° C. for 2 hours, reweighed (weighed), and calculated from the following equation. Curing residue (%) = (weight-weight of triethylenetetramine) x 100 / weight

The epoxy resin curing agent (C) used in the present invention is not particularly limited, and may be a known epoxy resin curing agent such as a phenol resin curing agent, a polyamine curing agent, or a polycarboxylic acid curing agent. Can be used. Specifically, as the phenolic resin-based curing agent, phenol novolak resin, cresol novolak resin,
Bisphenol novolak resin, poly p-vinyl phenol and the like are mentioned, and polyamine-based curing agents are diethylene triamine, triethylene tetramine, tetraethylene pentamine, dicyandiamide, polyamidoamine (polyamide resin), ketimine compound, isophorone diamine, m-xylene diamine , M-phenylenediamine, 1,3-bis (aminomethyl) cyclohexane, N
-Aminoethylpiperazine, 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, diaminodiphenylsulfone, etc., and polycarboxylic acid-based curing agents include phthalic anhydride, tetrahydrogen Examples include phthalic anhydride, methyltetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, hexachloroendmethylenetetrahydrophthalic anhydride, and methyl-3,6-endomethylenetetrahydrophthalic anhydride.

As described above, the adhesive for printed wiring of the present invention passes through the B-stage and the C-stage to form a target printed wiring board. In the B stage, the volatile components of the adhesive for printed wiring boards (solvent for production in the methoxy group-containing silane-modified epoxy resin (A), methanol produced by the sol-gel curing reaction of the methoxysilyl site of the resin (A)) It is necessary to prevent the generation of bubbles in the subsequent C stage by reducing the residual ratio of the solvent (E), which is a component of the adhesive for printed wiring boards. However, in the B stage, it is necessary to consider the interlayer adhesion of the subsequently obtained C stage layer to the conductor.
That is, it is necessary to leave the epoxy so that the adhesive layer of the B stage can develop a sufficient surface tack at a temperature at which the adhesive layer is brought into close contact with the conductor. It is preferable to use a latent curing agent that does not proceed with curing. As such a latent curing agent, a phenol resin-based curing agent is optimal.

From the viewpoint of the B-stage and C-stage design, the methoxy group-containing silane-modified epoxy resin (A)
The mixing ratio of the epoxy resin-based curing agent (C) to the epoxy group-derived silane-modified epoxy resin (A) is equivalent to one equivalent of the epoxy group derived from the functional group having active hydrogen in the epoxy resin-based curing agent (C). Is preferably in the range of 0.5 to 1.2 equivalents.

As described above, in order to avoid the formation of bubbles in the cured adhesive layer at the C stage, it is important to adjust the residual ratio of volatile components at the B stage.
A gel hardening accelerator (D) is indispensable. Examples of the sol-gel curing accelerator (D) include lithium, sodium, potassium, rubidium, cesium, magnesium,
Metals such as calcium, barium, strontium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, cerium, boron, cadmium, manganese; oxides, organic acid salts, halides, methoxides of these metals And the like. Among them, organic tin and organic acid tin are particularly preferable, and specifically, dibutyltin dilaurate, tin octylate and the like are effective.
The amount of the sol-gel curing accelerator (D) used is 0.1 to 5.0% by weight based on the cured residue of the adhesive for printed circuit boards.
It is preferred that If it is less than 0.1%, the sol-gel curing reaction in the B stage is not completed, and if it exceeds 5%, the adhesive composition tends to be thickened and the stability tends to be reduced.

Examples of the solvent (E) used in the present invention include ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone; ethyl acetate;
Esters such as butyl acetate, aromatics such as toluene and xylene, cellosolves such as cellosolve acetate and methyl cellosolve acetate, ethers such as tetrahydrofuran and diethylene glycol dimethyl ether, alcohols such as isopropyl alcohol and n-butyl alcohol, dimethylformamide And other aprotic polar solvents. For the same reason as selecting the solvent for the production of the alkoxy group-containing silane-modified epoxy resin (A),
Methyl ethyl ketone is most preferred. The mixing ratio of the solvent (E) is not particularly limited, and may be appropriately determined according to the method of applying the adhesive for a printed wiring board.

The adhesive for printed wiring boards of the present invention comprises the above-mentioned various essential components, ie, methoxy group-containing silane-modified epoxy resin (A), synthetic rubber (B), epoxy resin curing agent (C), sol- It is prepared by blending a gel hardening accelerator (D) and a solvent (E).

The composition of the adhesive for a printed wiring board can be appropriately adjusted according to its use. Usually, the weight of the cured product obtained from the adhesive in terms of silica is 3 to 40% by weight.
It is preferable to mix them. Here, the silica equivalent weight means silica obtained by subjecting methoxysilane partial condensate (2) used in methoxy group-containing silane-modified epoxy resin (A) contained in the adhesive for printed wiring boards to a sol-gel curing reaction. Means the weight of

The epoxy resin composition may contain a curing accelerator (different from the sol-gel curing accelerator (D)) for accelerating the curing reaction between the epoxy resin and the curing agent. it can. For example, tertiary amines such as 1,8-diaza-bicyclo [5.4.0] undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; Imidazoles such as -methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole; tributylphosphine;
Organic phosphines such as methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine; tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmorpholine tetraphenylborate and the like And tetraphenylboron salts. The curing accelerator is preferably used in a ratio of 0.1 to 5 parts by weight based on 100 parts by weight of the epoxy resin.

The adhesive for a printed wiring board of the present invention may contain, if necessary, a filler, a release agent, a surface treatment agent, a flame retardant, a viscosity modifier, a plasticizer as long as the effects of the present invention are not impaired. , Antibacterial agent, fungicide, leveling agent, defoamer, coloring agent,
You may mix | blend a stabilizer, a coupling agent, etc.

The method of using the adhesive for a printed wiring board is not particularly limited as long as it is a method of bonding a conductor and a heat-resistant insulating film. However, when the adhesive is used as an adhesive for a flexible printed wiring board or a TAB tape. ,
For example, the method described in JP-A-6-338681 can be preferably applied. As the heat-resistant organic insulating film used for the flexible printed wiring board, a so-called heat-resistant film made of polyimide, polyetherimide, aromatic polyamide, or the like, or a composite material made of polyethylene terephthalate, flexible epoxy / glass cloth, or the like is preferable. is there. Copper is generally used as the conductor.

A method for applying the printed wiring board adhesive of the present invention to a flexible printed wiring board will be described.
Applying the adhesive of the present invention to a heat-resistant organic insulating film,
Although the stage is cured, it is preferable to adjust the application amount so that the thickness of the cured layer is about 10 to 35 μm in consideration of the flexibility of the obtained B stage layer. In addition, the preparation conditions of the B-stage layer may be in the range of usually 90 to 130 ° C. and about 1 to 30 minutes. If the temperature is lower than 90 ° C., the solvent (E) tends to remain, or the sol-gel curing reaction of the alkoxy group-containing silane-modified epoxy resin is insufficient. 130 ° C
If it exceeds 300, the reaction between the epoxy group of the alkoxy group-containing silane-modified epoxy resin (A) and the epoxy resin curing agent (C) proceeds excessively, and the interlayer adhesion to the conductor becomes insufficient. Then, copper foil was placed on the obtained B-stage layer for 60 minutes.
Laminated at ~ 140 ° C and laminated, 150 ~ 21
By heating to about 0 ° C., the adhesive layer is C-stage cured.

The adhesive of the present invention is used for TAB,
A method for applying the adhesive tape for AB will be described. In the same manner as in the method of preparing the flexible printed wiring board, a B-stage layer is formed so that the film thickness is about 10 to 15 μm, and a release-protective film is attached to the B-stage layer as needed, thereby forming an adhesive for TAB. The resulting tape is obtained. As the protective film, polyethylene,
Polypropylene, polyethylene terephthalate and the like are preferably used. Alternatively, a tape with an adhesive for TAB can be produced by forming a B-stage layer on the protective film and then laminating a heat-resistant organic insulating film to the B-stage layer. The TAB adhesive tape obtained in this manner is used by removing the protective film at the time of use and laminating the tape on a copper foil.

[0034]

The adhesive for printed wiring boards of the present invention has excellent adhesiveness, heat resistance, workability and the like, and is particularly suitable for bonding a heat-resistant organic insulating film to a conductor.

[0035]

The present invention will be described below in detail with reference to examples and comparative examples. In each case,% is based on weight unless otherwise specified.

Production Example 1 (Production of methoxy group-containing silane-modified epoxy resin) Bisphenol A type epoxy resin (manufactured by Toto Kasei Co., Ltd., trade name) was installed in a reactor equipped with a stirrer, a cooling pipe, a thermometer, and a nitrogen blowing plug. “Epotote YD-011”, 336.0 g of epoxy equivalent (475 g / eq) and 268.8 g of methyl ethyl ketone were added and dissolved at 70 ° C. Furthermore, tetramethoxysilane partial condensate (manufactured by Tama Chemical Co., Ltd.
360.4 g of trade name “methyl silicate 51”) and 0.3 g of dibutyltin dilaurate as a catalyst were added, and 80
After a reflux reaction at 6 ° C. for 6 hours, the mixture was cooled to 50 ° C., and 33.6 g of methyl alcohol was added to obtain a methoxy group-containing silane-modified epoxy resin solution. In addition, at the time of preparation, (weight in terms of silica of methoxysilane partial condensate (2) / weight of epoxy resin (1)) = 0.55, and (methoxy group partial condensate (2) equivalent of methoxy group / bisphenol) (Equivalent of hydroxyl group of epoxy resin of epoxy resin (1)) = 10.0
It is. From the ¹ H-NMR (CDCl ₃ solution) measurement results of the resin solution, the methine peak of the epoxy ring (3.3 ppm)
100%) and the peak of hydroxyl groups in the epoxy resin (around 3.85 ppm) was about 50%.
It was confirmed that the percentage decreased. The cured residue of the obtained methoxy group-containing silane-modified epoxy resin solution was 50.8.
%, The epoxy equivalent was 1,400 g / eq, and the ratio of the amount of silica contained in the cured residue was 36%.

Production Example 2 (Production of methoxy group-containing silane-modified epoxy resin) Epotote YD-011 was placed in the same reactor as in Production Example 1.
332.0 g and methyl ethyl ketone 400.0 g
Was added and dissolved at 70 ° C. Furthermore, methyltrimethoxysilane partial condensate (trade name “MTMS” manufactured by Tama Chemical Co., Ltd.)
-A ") and 1.0 g of dibutyltin dilaurate were added, and refluxed at 80 ° C for 6 hours to obtain a methoxy group-containing silane-modified epoxy resin solution. Incidentally, (weight in terms of silica of methoxysilane partial condensate (2) / weight of bisphenol-type epoxy resin (1)) at the time of preparation = 0.51, (equivalent of methoxy group of methoxysilane partial condensate (2) / bisphenol) (Equivalent of the hydroxyl group of the epoxy resin of the type (1)) = 5.2. From the ¹ H-NMR (CDCl ₃ solution) measurement results of the resin solution,
The methine peak of the epoxy ring (around 3.3 ppm) is 10
It was confirmed that 0% was retained and that the peak (around 3.85 ppm) of the hydroxyl group in the epoxy resin had disappeared. The resulting methoxy group-containing silane-modified epoxy resin solution had a cured residue of 49.9% and an epoxy equivalent of 1
400 g / eq, the ratio of the amount of silica contained in the cured residue was 35%.

Production Example 3 (Production of methoxy group-containing silane-modified epoxy resin) 185.0 g of Epotote YD-011 and diethylene glycol dimethyl ether 400 were prepared in a reactor equipped with a stirrer, a water separator, a thermometer, and a nitrogen inlet valve. .0
g was dissolved at 70 ° C. Methyl silicate 5
396.9 g and 1.0 of dibutyltin dilaurate
g was added thereto and subjected to a methanol removal reaction at 90 ° C. for 6 hours to obtain a methoxy group-containing silane-modified epoxy resin solution. Incidentally, (weight in terms of silica of methoxysilane partial condensate (2) / weight of bisphenol type epoxy resin (1)) at the time of preparation = 1.09, (equivalent of methoxy group of methoxysilane partial condensate (2) / bisphenol) (Equivalent of hydroxyl group of epoxy resin (1)) = 20.0. From the ¹ H-NMR (CDCl ₃ solution) measurement results of this resin solution, 100% of the methine peak of the epoxy ring (around 3.3 ppm) is maintained, and the peak of the hydroxyl group in the epoxy resin (around 3.85 ppm) Was confirmed to have disappeared. The cured residue of the obtained methoxy group-containing silane-modified epoxy resin solution was 39.5%, the epoxy equivalent was 2500 g / eq, and the ratio of the amount of silica contained in the cured residue was 53%.

Comparative Production Example 1 Epotote YD-011 was dissolved in methyl ethyl ketone, and the nonvolatile content was 40.0% and the epoxy equivalent was 1200 g / e.
q was an epoxy resin solution.

Comparative Production Example 2 Epototo YD-011 and bisphenol A type epoxy resin (trade name "Epototo YD-1" manufactured by Toto Kasei Co., Ltd.)
27 ", an epoxy equivalent of 190 g / eq) in a weight ratio of 2: 3.
Was dissolved in methyl ethyl ketone to obtain an epoxy resin solution having a nonvolatile content of 40% and an epoxy equivalent of 360 g / eq.

Comparative Production Example 3 Epotote YD-011 (640 g), 640 g of methyl ethyl ketone, and methyl silicate 51 (52
1.3 g), a nonvolatile content of 50%, an epoxy equivalent of 1
An epoxy resin-methoxysilane resin solution of 300 g / eq, in which the proportion of silica contained in the cured residue was 42%.

(Preparation of Adhesive for Printed Wiring Board) Each of the above resin solutions was used as the methoxy group-containing silane-modified epoxy resin (A), and nitrile rubber was used as the synthetic rubber (B) (trade name "Nippon Zeon Co., Ltd.," NP1031 ") as a phenol novolak resin (trade name" Tamanol 759 "manufactured by Arakawa Chemical Industries, Ltd.) as a curing agent (C) for epoxy resin
And tin octylate as a sol-gel curing accelerator (D)
Methyl ethyl ketone was mixed as the solvent (E) in the amounts shown in Table 1 to obtain various adjusted varnishes (adhesives for printed wiring boards).

[0043]

[Table 1]

The units of numerical values in Table 1 are all parts by weight.

(Preparation of Test Board) The adhesive for printed wiring boards obtained above (the compositions of the present invention (Examples 1 to 3) are referred to as compositions A to C in order, and those for comparison (Comparative Examples) 1 to
3) are referred to as compositions a to d) in order.
It was applied on a polyimide film with a bar coater so as to have a thickness of 0 μm, and dried at 110 ° C. for 5 minutes to make the adhesive layer B-stage. A copper foil was overlaid on the adhesive layer, laminated at 110 ° C., and then cured at 160 ° C. for 3 hours (C stage) to prepare a test plate.

(Heat Resistance, Adhesiveness) Using the test plates obtained above, adhesive performance was evaluated by the following method. The evaluation results are shown in Table 2. (1) Peeling strength The obtained test plate was fixed, the copper foil was peeled off at a speed of 50 mm / min in the direction of 90 °, and the strength was measured (JIS).
C 6481). (2) Solder heat resistance After the obtained test plate was floated in a flow solder bath for 30 seconds,
The maximum temperature at which swelling and peeling did not occur was measured (JIS
C 6481).

[0047]

[Table 2]

As is clear from Table 2, the printed wiring board using the adhesive for printed wiring boards of the present invention has higher heat resistance and copper foil compared to a printed wiring board using a conventional epoxy adhesive. It can be seen that the adhesiveness to is excellent.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4J040 CA042 CA072 CA082 CA142 DA142 EB052 EB062 EC061 EC461 GA04 HB03 HB09 HB15 HB19 HB28 HB31 HB43 HC05 HC08 HC11 HD16 HD42 KA16 KA17 KA23 LA01 LA06 LA08 NA20 A31A03 DD GG02

Claims (11)

[Claims] 1. A methoxy group-containing silane-modified epoxy resin (A) obtained by subjecting a bisphenol type epoxy resin (1) and a methoxysilane partial condensate (2) to a dealcoholation reaction, a synthetic rubber (B), and curing for an epoxy resin. An adhesive for printed wiring boards, comprising an agent (C), a sol-gel curing accelerator (D) and a solvent (E). 2. The adhesive for printed wiring boards according to claim 1, wherein the bisphenol type epoxy resin (1) is a bisphenol type epoxy resin having an average epoxy equivalent of 350 to 1000 g / eq. 3. The adhesive for printed wiring boards according to claim 1, wherein the methoxysilane partial condensate (2) is a partial condensate of tetramethoxysilane or methyltrimethoxysilane. 4. The methoxy group-containing silane-modified epoxy resin (A) has a methoxysilane partial condensate (2) silica equivalent weight / bisphenol type epoxy resin (1) weight (weight ratio) of 0.25 to 1: 1. The adhesive for printed wiring boards according to any one of claims 1 to 3, which is 2. 5. The synthetic rubber (B) is at least one selected from polyisobutene, butadiene rubber, styrene-butadiene rubber, nitrile rubber, and chloroprene rubber.
The adhesive for printed wiring boards according to any one of claims 1 to 4, which is a seed. 6. The adhesive for printed wiring boards according to claim 1, wherein the epoxy resin curing agent (C) is a phenolic resin curing agent. 7. The adhesive for printed wiring boards according to claim 1, wherein the sol-gel curing accelerator (D) is at least one selected from dibutyltin dilaurate and tin octylate. 8. The adhesive for printed wiring boards according to claim 1, wherein the solvent (E) has a boiling point of 70 to 110 ° C. 9. The compounding ratio of the synthetic rubber (B) is 100% of the cured residue of the methoxy group-containing silane-modified epoxy resin (A).
30 to 100 parts by weight with respect to 1 part by weight, and the mixing ratio of the curing agent for epoxy resin (C) is 1 part by weight of the epoxy group derived from the methoxy group-containing silane-modified epoxy resin (A). The functional group having active hydrogen in the curing agent (C) is 0.5 to 1.2 equivalent.
The adhesive for printed wiring boards according to any one of the above. 10. The adhesive for a printed wiring board according to claim 1, which is an adhesive for a flexible printed wiring board. 11. The adhesive for printed wiring boards according to claim 1, which is an adhesive for a tape automated bonding tape.