JPH1135913A - Anisotropic conductive adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting, anisotropic conductive adhesive which enables electric connections between fine circuits such as a connection between an LCD(liquid crystal display) and a TCP(tape carrier package) or a connection between a TCP and a PCB(printed circuit board), especially at a low temperature in a short time, and has a good storage stability, adhesion, connection reliability and working performance. SOLUTION: An anisotropic conductive adhesive is prepared by dispersing conductive particles in a resin composition comprising a (meth)cryloylated novolak resin having a phenolic hydroxyl group represented by the formula, an organic peroxide and a thermoplastic elastomer. Here, the (meth)acryloylated novolak resin comprises two or more resins which differ in the ratio of the phenolic hydroxyl group to the (meth)acryloyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrical connection between fine circuits such as a connection between an LCD (liquid crystal display) and a TCP (tape carrier package) and a connection between a TCP and a PCB (printed circuit board). The present invention relates to an anisotropic conductive adhesive used.

[0002]

2. Description of the Related Art In recent years, anisotropic conductive adhesives in which conductive particles are dispersed in an adhesive resin have been used for liquid crystal displays LCD and T.D.
The necessity of various fine circuit connections such as connection between CP and TCP and PCB has been dramatically increased, and an anisotropic conductive adhesive has been used as a connection method thereof. In this method, an anisotropic conductive adhesive is sandwiched between members to be connected and heated and pressed, so that electrical insulation is maintained between adjacent terminals in the surface direction, and electrical conduction is provided between upper and lower terminals. . With the recent trend toward smaller and lighter electronic components, in such circuit connection applications, the circuit connection pitch is becoming finer, causing electrical shorts between adjacent terminals, and the heat resistance of the adherend is low, resulting in poor connection. With conventional methods such as soldering, it is becoming impossible to make good connections, such as the adherend being deteriorated by temperature.This anisotropic conductive adhesive is a material that is indispensable for connecting fine circuits Has become.

[0003] The anisotropic conductive adhesive is generally classified into a thermoplastic resin type and a thermosetting resin type. Therefore, a thermosetting type such as an epoxy resin type having excellent long-term connection reliability is being used more widely than a thermoplastic type.

As for the thermoplastic type anisotropic conductive adhesive, SBS (styrene-butadiene-styrene), SI
Styrene-based copolymers such as S (styrene-isoprene-styrene) and SEBS (styrene-ethylene-butadiene-styrene) have been mainly used, but these thermoplastic types are basically used in a melt-fusion method. The workability is generally considered to be good because it can be applied at a relatively low temperature and in a short time compared to the thermosetting one if the conditions are selected, but the moisture resistance and chemical resistance of the resin However, it was not able to withstand a long-term environmental test because of its low reliability and low connection reliability.

On the other hand, as a thermosetting type anisotropic conductive adhesive which is currently mainstream, an epoxy resin type thermosetting type having a good balance between storage stability and curability is widely used. However, in practice, these thermosetting types are used at a temperature of 150 to 200 ° C. due to their curing reactivity in order to achieve both storage stability and resin curability.
It is necessary to heat and cure for about a second.
At a temperature of 0 ° C. or less, it was difficult to cure the resin in a practical connection time.

Further, regarding the storage stability, for example, B
F3 amine complexes, dicyandiamide, organic acid hydrazide, a compound containing a latent curing agent such as an imidazole compound and the like have been proposed, but those having excellent storage stability require a long time or high temperature for curing, and a low temperature. -Those which can be cured in a short time have a problem that storage stability is inferior, and all have advantages and disadvantages.

[0007] In addition to the problems described above, there has been a growing demand for peeling and connecting (so-called "repairing") the members once connected due to a displacement or the like without damaging or damaging the connected members. On the other hand, when a thermosetting anisotropic conductive adhesive is used, most of them have high adhesive strength,
Although it has the advantage of high reliability, it has been extremely difficult to respond to seemingly contradictory demands for easy peeling without damaging the adherend, and no satisfactory product has been obtained.

[0008] In particular, recently, the LCD module has rapidly increased in size, definition, and frame width.
The miniaturization of the connection pitch and the narrowing of the connection have also progressed rapidly. For this reason, for example, in the connection between the LCD and the TCP, a connection pattern shift occurs due to the extension of TCP at the time of connection, and a member inside the LCD is thermally affected by the temperature at the time of connection because the connection portion is narrow. The problem has arisen. Further, in the connection between the TCP and the PCB, since the PCB has become longer, there has been a problem that the PCB and the LCD are warped due to heating during the connection, and the wiring of the TCP is disconnected.

Therefore, it was considered to solve these problems by connecting at a lower temperature. However, as described above, for example, when connecting with a conventional thermoplastic type anisotropic conductive adhesive, Although connection at a relatively low temperature is possible, there is a problem that the connection reliability is poor due to the low moisture resistance and heat resistance of the resin. Also, when trying to connect at a low temperature with an epoxy resin-based anisotropic conductive adhesive, which is the mainstream of the thermosetting type, it is necessary to lengthen the connection time to cure the resin, which is not practically applicable. .

As an anisotropic conductive adhesive which enables low-temperature connection, an adhesive resin in which a cationically polymerizable substance and a sulfonium salt are blended and conductive particles are dispersed (JP-A-7-90237). Also, there has been proposed an epoxy resin or the like and a dispersion of conductive particles in a 4- (dialkylamino) pyridine derivative (Japanese Patent Application Laid-Open No. 4-189883). It has not been put to practical use due to problems such as corrosion of the steel.

Further, in order to increase the compatibility between the radically polymerizable resin and the thermoplastic elastomer, a combination of a radically polymerizable resin, an organic peroxide and a thermoplastic air elastomer is considered to enable low-temperature connection. We have devised measures such as blending maleimide and applying a novolak resin having a phenolic hydroxyl group to the radically polymerizable resin, but the curability, storage stability, adhesion, and connection reliability of the anisotropic conductive adhesive have been devised. However, it has not yet been optimized to a level that maintains all characteristics such as workability in a well-balanced manner.

That is, at present, a resin system that satisfies all of curability, storage stability, adhesiveness, connection reliability, workability, and the like in a well-balanced manner has not been obtained. The demand for anisotropic conductive adhesives that are excellent in storage stability, adhesiveness, connection reliability, workability, and the like has become very strong.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems of the prior art, and has been made as a result of various studies. The purpose of the present invention is to provide a connection between an LCD and a TCP or a TCP. Thermosetting anisotropic electrical connection between microcircuits, such as the connection between PCB and PCB, which can be connected especially at low temperature and short time, and has excellent storage stability, adhesiveness, connection reliability and workability. It is intended to provide a conductive adhesive.

[0014]

Means for Solving the Problems The present inventor has developed an adhesive containing a radical polymerizable resin, an organic peroxide, and a thermoplastic elastomer, which can achieve both low-temperature quick-curing and storage stability. When a thermosetting anisotropic conductive adhesive in which conductive particles are dispersed is used for heat-curing connection, a phenolic hydroxyl group-containing (meth) acryloylated novolak resin having a phenolic hydroxyl group represented by the formula (1) is used. Hydroxyl group and (meth)
A mixture of two or more acryloyl groups having different ratios of acryloyl groups provides a well-balanced heat-curable anisotropic conductive adhesive with sufficient adhesiveness and connection reliability in various environments and good workability. Have been obtained and the present invention has been accomplished.

[0015]

Embedded image

That is, according to the present invention, conductive particles are dispersed in a resin composition comprising a (meth) acryloylated novolak resin having a phenolic hydroxyl group having the structure of formula (1), an organic peroxide, and a thermoplastic elastomer. The anisotropically conductive adhesive according to claim 1, wherein said (meth) acryloylated novolak resin comprises a mixture of two or more phenolic hydroxyl groups and (meth) acryloyl groups having different ratios. Adhesive.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The (meth) acryloylated novolak resin having a phenolic hydroxyl group used in the present invention is not particularly limited as long as it has the structure of the formula (1). Although the ratio of the phenolic hydroxyl group to the (meth) acryloyl group of the (meth) acryloylated novolak resin having a phenolic hydroxyl group used herein is not particularly limited,
8: 2-1: 9 is preferred. The higher the proportion of phenolic hydroxyl groups, the better the adhesion to the adherend, but the lower the curability and the lower the crosslink density. Further, since the melting point is high, the flowability of the resin is insufficient at a low temperature connection, and the stickiness of the film becomes too small when the film is formed, and the workability is deteriorated. In particular, when the ratio is more than 8: 2, the above-mentioned characteristics are extremely high, and thus the adhesive cannot be practically used as an anisotropic conductive adhesive. Conversely, the lower the proportion of phenolic hydroxyl groups, the better the curability, but the higher the crosslink density and the lower the adhesion to the adherend. Also,
Since the melting point is low, the flow of the resin can be sufficiently ensured even at a low temperature connection, but when the film is formed, the stickiness of the film becomes too large and the workability is deteriorated. In particular, if the ratio is less than 1: 9, the above-mentioned characteristics are extremely high, and thus the anisotropic conductive adhesive cannot be practically used.

As described above, the ratio between the phenolic hydroxyl group and the (meth) acryloyl group greatly affects the curability, adhesiveness, connection reliability, workability, and the like when an anisotropic conductive adhesive is used. The present invention is characterized in that two or more types of novolak resins having the structure of the formula (1) having different ratios of phenolic hydroxyl groups and (meth) acryloyl groups are used in order to optimize these characteristics.

In the present invention, the (meth) acryloylated novolak resin having a phenolic hydroxyl group having the structure of the formula (1) is obtained by mixing two or more kinds of resins having different ratios of hydroxyl group and (meth) acryloyl group. If so, the mixing ratio of two or more (meth) acryloylated novolak resins having the structure of formula (1) is not particularly limited. Of course, the ratio of phenolic hydroxyl groups to (meth) acryloyl groups is optimally balanced in accordance with the application, taking into account properties such as curability, adhesiveness, connection reliability, and workability as an anisotropic conductive adhesive. Needless to say, it should be changed. For example, by combining a phenolic hydroxyl group with a (meth) acryloyl group in a ratio of about 8: 2 as high as about 8: 2 and a phenolic hydroxyl group in a ratio as low as about 4: 6, for example, the ratio is between the resins of 8: 2 and 4: 6 It is possible to bring out the characteristics that make use of the advantages of both the 8: 2 and 4: 6 ratio resins, which cannot be achieved by using only the 5: 5 or 7: 3 ratio resin alone.

Further, for example, in addition to a novolak resin having a structure of the formula (1) having a different ratio of a phenolic hydroxyl group to a (meth) acryloyl group, the compound has at least one carbon-carbon double bond in the molecule, Those capable of radical polymerization may be used alone or in combination of two or more.

Examples of the radically polymerizable compound include acrylates such as vinyl ester resin and urethane acrylate resin, unsaturated polyester resin, diallyl phthalate resin and the like. Above all, a vinyl ester resin and a urethane acrylate resin having both curability and storage properties, heat resistance, moisture resistance and chemical resistance of a cured product can be suitably used. Further, in order to ensure the storage stability, a polymerization inhibitor such as quinones, polyhydric phenols and phenols can be added in advance (for example, JP-A-4-146951). In order to further improve curability, fluidity during heating, and workability, acrylates such as trimethylolpropane triacrylate (TMPTA), pentaerythritol diallylate monostearate, tetraethylene glycol diacrylate, pentaerythritol tetraacrylate, and styrene. It may be used after being diluted with various monomers or a common reactive diluent.

When the other radically polymerizable resin is used in combination, the proportion of the (meth) acryloylated novolak resin having a phenolic hydroxyl group used in the present invention in the radically polymerized resin is not particularly limited. However, 20 wt% to 100 wt% is preferable. This is because if the proportion is 20% or less, the properties of the (meth) acryloylated novolak resin having a phenolic hydroxyl group cannot be utilized, and sufficient adhesiveness cannot be obtained when an anisotropic conductive adhesive is used.

The method for producing the (meth) acryloylated novolak resin having a phenolic hydroxyl group having the structure of the formula (1) is not particularly limited. For example, it may be prepared by an addition reaction between a glycidyl group of glycidyl (meth) acrylate and a hydroxyl group of a novolak resin, or an addition reaction between a carboxyl group of (meth) acrylic acid and an epoxy group of a novolak type epoxy resin. . The reaction between these novolak resins and glycidyl methacrylate is
The ratio of the phenolic hydroxyl group to the (meth) acryloyl group in the (meth) acryloylated novolak resin having a phenolic hydroxyl group can be easily controlled by changing the reaction conditions such as the charging ratio.

The novolak resins used herein include those obtained by the condensation reaction of formaldehyde with alkylphenols such as phenol, cresol, xylenol, butylphenol and nonylphenol, and polyhydric phenols such as catechol, resorcinol and hydroquinone. There is no particular limitation, but phenol, cresol, and the like are desirable in consideration of adhesiveness, connection reliability, and rapid curability when an anisotropic conductive adhesive is used.

The average number of nuclei of the (meth) acryloylated novolak resin having a phenolic hydroxyl group is not particularly limited, but is preferably 5 to 10. If the average number of nuclei is 5 or less, problems such as a decrease in curability and a decrease in adhesiveness in the case of using an anisotropic conductive adhesive occur.
On the other hand, if it is more than 10, the softening point becomes high, the fluidity of the anisotropic conductive adhesive becomes insufficient, and sufficient connectivity cannot be obtained.

The organic peroxide used in the present invention is not particularly limited. For example, 1,1,3,3-
Tetramethylbutyl peroxy-2-ethyl hexanate, t-butyl peroxy-2-ethyl hexanate,
t-hexylperoxy-2-ethylhexanate,
1,1-bis (t-butylperoxy) -3,3,5-
Trimethylcyclohexane, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, bis (4-t-butylcyclohexyl) peroxydicarbonate and the like can be mentioned. These peroxides can be used alone or as a mixture of two or more kinds of organic peroxides for controlling curability. Various polymerization inhibitors can be added in advance to improve the storage stability. Further, it may be used by diluting it with a solvent or the like in order to facilitate the work of dissolving the resin. Naturally, the type and amount of the organic peroxide used in the present invention are determined depending on the balance between the curability and the preservability of the adhesive when each peroxide is compounded.

The thermoplastic elastomer used in the present invention is not particularly restricted but includes, for example, polyester resins,
Polyurethane resins, polyimide resin, polybutadiene, polypropylene, styrene-butadiene-styrene copolymer, polyacetal resin, polyvinyl butyral resin, butyl rubber, chloroprene rubber, polyamide resin, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-methacrylic acid copolymer Coalesce, acrylonitrile-butadiene-styrene copolymer, polyvinyl acetate resin, nylon, styrene-isoprene copolymer, styrene-butylene-styrene block copolymer,
Styrene-ethylene-butylene-styrene block copolymer, polymethyl methacrylate resin and the like can be used. Considering properties such as adhesion and connection reliability when anisotropically conductive adhesive is used among them, acrylonitrile-butadiene-methacrylic acid copolymer, polyester,
Polyamide resin, nylon, polyvinyl butyral resin, styrene-ethylene-butylene-styrene block copolymer and the like are desirable.

In the present invention, a maleimide resin may be added in order to improve the compatibility between the (meth) acryloylated novolak resin having a phenolic hydroxyl group and the thermoplastic elastomer. Examples of the maleimide resin used here include those having a chemical structure exemplified by the formula (2). However, the usage conditions (connection temperature and connection time) of the anisotropic conductive adhesive and the radical polymerizable resin used The chemical structure can be selected or changed depending on the type of the thermoplastic elastomer. Further, maleimide may be modified with an amine in order to further improve the compatibility between the radical polymerizable resin and the thermoplastic elastomer.

[0029]

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The conductive particles used in the present invention are not particularly limited as long as they have conductivity, and various kinds of metals such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, and gold can be used. And metal alloys, metal oxides, carbon, graphite, glass and ceramics, and plastic particles coated with a metal on the surface.
Appropriate particles, materials, and amounts of these conductive particles can be selected according to the pitch and pattern of the circuit to be connected, the thickness and material of the circuit terminals, and the like.

Further, in the anisotropic conductive adhesive of the present invention,
If necessary, a suitable amount of a coupling agent may be added. The purpose of adding the coupling agent is to modify the adhesiveness of the adhesive interface of the anisotropic conductive adhesive, improve the adhesive strength, heat resistance, moisture resistance and improve the connection reliability. Although not particularly limited, a silane coupling agent can be suitably added and used. For example, epoxy silane, aminosilane, mercaptosilane, acrylsilane (for example, β- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, etc.).

[0032]

The present invention will be described below with reference to examples and comparative examples. <Example 1> A methacryloylated phenol novolak resin having a structure of formula (1) (m: n = 2: 8, m + n
= 8) and a methacryloylated phenol novolak resin having the structure of the formula (1) (m: n = 6: 4, m + n =
8) was dissolved in methyl ethyl ketone at a ratio of 1: 1
100 parts by weight of a 0% solution, 100 parts by weight of a 20% solution obtained by dissolving an acrylonitrile-butadiene-methacrylic acid copolymer having a structure of the formula (3) in methyl ethyl ketone,
2 parts by weight of 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate and 2 parts by weight of nickel / gold plated polystyrene particles (average particle size: 5 μm) are uniformly mixed and released. It was cast on a treated PET (polyethylene terephthalate) film and dried to obtain an anisotropic conductive film.

[0033]

Embedded image Carboxyl group content: 4.0 mol% Acrylonitrile content: 27 wt% Molecular weight: about 100,000

Example 2 A methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
3: 7, m + n = 8) and a methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
5: 5, m + n = 5) was dissolved in methyl ethyl ketone at a ratio of 2: 1, 100 parts by weight of a 50% solution, and the acrylonitrile-butadiene-methacrylic acid copolymer having the structure of the formula (3) was dissolved in methyl ethyl ketone. 100 parts by weight of the obtained 20% solution, 2 parts by weight of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, and 2 parts by weight of polystyrene particles (average particle size: 5 μm) plated with nickel / gold. Was uniformly mixed, cast on a PET film that had been subjected to a release treatment, and dried to obtain an anisotropic conductive film.

Example 3 A methacryloylated cresol novolak resin having the structure of the formula (1) (m: n =
4: 6, m + n = 8) and a methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
5: 5, n + m = 6) at a ratio of 1: 1 in 100% by weight of a 50% solution in methyl ethyl ketone, and a saturated copolymerized polyester (molecular weight: 25,000, softening point: 120 ° C.) in 100% by weight in a 20% solution in methyl ethyl ketone. ,
2 parts by weight of 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate and 2 parts by weight of nickel / gold plated polystyrene particles (average particle size: 5 μm) are uniformly mixed and released. It was cast on a treated PET film and dried to obtain an anisotropic conductive film.

Example 4 A methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
3: 7, m + n = 8) and a methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
5: 5, m + n = 8) in a ratio of 2: 1 in methyl ethyl ketone, 100 parts by weight of a 20% solution, and an epoxidized styrene-ethylene-butylene-styrene block copolymer in 100 parts by weight of a 20% solution. , 2,2-bis [4- (4-
[Aminophenoxy) phenyl] propane-type bismaleimide resin in tetrahydrofuran 20% solution 10
0 parts by weight, 2 parts by weight of 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, and nickel / gold plated polystyrene particles (average particle size: 5 μm)
m) is uniformly mixed with 2 parts by weight of
The film was cast on a T (polyethylene terephthalate) film and dried to obtain an anisotropic conductive film.

[0037]

Embedded image

Example 5 A methacryloylated phenol novolak resin having the structure of the formula (1) (m: n =
2: 8, m + n = 7) and a methacryloylated phenol novolak resin having a structure of the formula (1) (m: n =
6: 4, m + n = 8) in a ratio of 1: 1 in methyl ethyl ketone, 100 parts by weight of a 30% solution, a phenol novolak type vinyl ester resin represented by the formula (2) in 100 parts by weight of a 20% solution in methyl ethyl ketone, Saturated copolymerized polyester (molecular weight 25,000, softening point 120
C) in methyl ethyl ketone 100%
Parts by weight, 2 parts by weight of 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate,
Gold-plated polystyrene particles (average particle size 5 μm)
2 parts by weight are mixed uniformly, and PET is released.
(Polyethylene terephthalate)
After drying, an anisotropic conductive film was obtained.

Comparative Example 1 The same as Example 1 except that the methacryloylated phenol novolak resin having the structure of the formula (1) (m: n = 6: 4, m + n = 8) was not used. A resin mixture was prepared, cast on a PET (polyethylene terephthalate) film that had been subjected to a release treatment, and dried to obtain an anisotropic conductive film.

Comparative Example 2 The same as Example 4 except that the methacryloylated phenol novolak resin (m: n = 4: 6, m + n = 8) having the structure of the formula (1) was not used. A resin mixture was prepared, cast on a PET (polyethylene terephthalate) film that had been subjected to a release treatment, and dried to obtain an anisotropic conductive film.

Comparative Example 3 Example 5 was the same as Example 5 except that the methacryloylated phenol novolak resin (m: n = 6: 4, m + n = 8) having the structure of formula (1) was not used. A resin mixture was prepared, cast on a PET (polyethylene terephthalate) film that had been subjected to a release treatment, and dried to obtain an anisotropic conductive film.

<Evaluation Results> The anisotropic conductive films obtained in Examples and Comparative Examples were evaluated for adhesive strength, connection reliability,
Table 1 shows the results of evaluating the workability. The anisotropic conductive films used as test pieces were all 15 μm thick, 2.0 mm
Is the width and the adherend is copper foil / polyimide = 25/75 μm
With 0.5 μm tin plating (terminal pitch 0.1 mm, number of terminals 200) and sheet resistance 30Ω /
A 1.1 mm-thick glass (hereinafter referred to as ITO glass) coated with an indium / tin oxide conductive film of □ on the entire surface was used.・ Adhesive strength TCP and I under conditions of 150 ° C, 30 kg / cm ² , 15 s
The anisotropic conductive film on which the TO glass was produced was pressure-bonded and connected, and evaluated by a 90 ° peel test. -Connection resistance value The connection resistance between the adjacent terminals on the TCP side of the sample prepared in the same manner as in the adhesive strength measurement was measured.・ Connection reliability A sample prepared in the same manner as the adhesion measurement was taken at a temperature of 85 ° C.
The treatment was performed at a humidity of 85% for 500 hours, and the connection resistance between adjacent terminals was measured. Those that could not be measured were OPEN. -Storage stability The prototype anisotropic conductive film was allowed to stand at room temperature (22 ° C) for 7 days, and a sample was prepared in the same manner as in the measurement of the adhesive strength. -Workability The prototype anisotropic conductive film was provisionally pressure-bonded to ITO glass (70 ° C, 5 kg / cm ² , 2 s condition), and the PET film was peeled off. A case where the resin of the anisotropic conductive film remained on the glass and only PET was peeled was judged to be good, and a case where the resin was less sticky and the resin was peeled from the glass together with the PET film was regarded as defective. Also, set the prototype anisotropic conductive film on the unwinding device, and check whether the sticking of the resin surface does not stick to the rollers in the middle of the device when unwinding and whether the transfer is performed smoothly. A case where the transfer was not smooth due to many cases was regarded as defective.

[0043]

[Table 1]

[0044]

According to the present invention, a resin composition comprising a (meth) acryloylated novolak resin having a phenolic hydroxyl group having the structure of the formula (1), an organic peroxide, and a thermoplastic elastomer is used. When a heating effect connection is made using an anisotropic conductive adhesive in which particles are dispersed, the (meth)
The acryloylated novolak resin is a mixture of two or more phenolic hydroxyl groups and (meth) acryloyl groups with different ratios of phenolic hydroxyl groups, making it possible to connect at extremely low temperatures in a short time, and to set the resin's curability, storage stability, adhesion, and connection reliability. It is possible to obtain an anisotropic conductive adhesive capable of maintaining a good balance of properties, workability, and the like in a good range.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01B 1/20 H01B 1/20

Claims (1)

[Claims] 1. A (meth) acryloylated novolak resin having a phenolic hydroxyl group having a structure represented by the following formula (1):
In an anisotropic conductive adhesive in which conductive particles are dispersed in a resin composition comprising an organic peroxide and a thermoplastic elastomer, the (meth) acryloylated novolak resin has a ratio of phenolic hydroxyl groups to (meth) acryloyl groups. An anisotropic conductive adhesive comprising a mixture of two or more of the following. Embedded image